We thank Dr. Helene Bernstein for providing us with access to her flow cytometer. We also thank CFAR flow cytometry facility for the flow cytometry services. This project was in part supported by CTSC core utilization funding and STERIS corporation/University Hospitals-Division of Infectious diseases grant to PP.

NOTE: The experiments using mice were performed in accordance to the institutional animal welfare committee (IACUC) guidelines.
1. Reconstituting the Rag-1-/- Mice with In Vitro Cultured Th17 cells (Three days prior to Infection)
<ol>
	<li>For establishing Th17 cells, culture CD4+&#160;CD44low&#160;CD62Lhigh&#160;CD25-&#160;na&#239;ve T cells (3 x 104) in U-bottom 96 well plates alone, or co-culture them along with 3 x 104&#160;CD4+CD25+Foxp3+Tregs&#160;in the presence of soluble&#160;&#160;&#945;-CD3 (1 &#181;g/ml),&#160;&#945;-CD28 (2 &#181;g/ml) antibodies and antigen presenting cells, under Th17 conditions (polarized using IL-6 (25 ng/ml), TGF- &#946;&#160;(2 ng/ml),&#160;&#160;&#945;-IFN-&#947;&#160;(2&#160;&#181;g/ml) and&#160;&#945;&#160;-IL-4 (2&#160;&#181;g/ml)) for three to four days.&#160; 
	NOTE: Na&#239;ve cells and Tregs were sorted using fluorescence activated cell sorting (FACS) and magnetic cell isolation procedures and cultured as described previously19-22.</li>
	<li>On day 4, after resuspending the Th17 cells using the pipette, collect them from cultures, and centrifuge them under sterile conditions.
	<ol>
		<li>Take a small aliquot of these cells to examine their viability and for phenotyping. Resuspend them in 500 &#181;l of RPMI medium, add propidium iodide (200 ng/ml) and assess their viability immediately by flow cytometry. Perform phenotyping by flow cytometry assessment of IL-17A production after restimulation (see section 6.3).</li>
	</ol>
	</li>
	<li>Centrifuge and wash the main bulk of the cells in sterile PBS at 480 x g for 6 min at 4&#176; C in all the steps unless otherwise specified.</li>
	<li>Use these cells for adoptive transfer into 6-8 week old CD45.2 Rag1-/- immunodeficient mice.
	<ol>
		<li>Resuspend the cells at 1 x 107 cells/ml cell density using cold sterile PBS.</li>
		<li>Inject 100 &#956;l of the cells by intraperitoneal injection, using 25 G needles on 1 ml tuberculin syringes, such that one mouse receives 1 x 106 cells. Some mice will receive PBS or Th17 cells only, and other mice will receive Th17 cells that were co-cultured with Treg cells. 
		NOTE: Perform all the steps aseptically.</li>
	</ol>
	</li>
</ol>
2. Growing C. albicans for infection (one day prior to Infection)
<ol>
	<li>Before inoculation, disperse five colonies of the CAF2-1 C. albicans laboratory strain in 100 &#181;l of sterile PBS suspension, and add the suspension to the sterile broth.</li>
	<li>Inoculate 5 colonies of the C. albicans in 50 ml of the Yeast nitrogen base (YNB without amino acids)/Peptone/Dextrose broth medium and incubate in a shaker incubator at 30 &#176;C for 15&#8211;18 hr at 130 rpm.</li>
	<li>Monitor the broth for cloudiness, as that is an indication for the growth of the fungus.</li>
</ol>
3. Candida Harvesting and Counting Procedure (On the Day of Infection)
<ol>
	<li>Collect 10 ml of Candida broth in 15 ml tubes. For larger volumes, collect Candida in 50 ml tubes.</li>
	<li>Centrifuge the blastospores at 1900 x g for 5 min at RT&#160;in all the steps unless otherwise specified. Pellet the blastospores by centrifugation, followed by the removal of the supernatant.</li>
	<li>If there is more than one tube, pool the Candida blastospores from multiple tubes, adding sterile PBS to the pellets and resuspend them in 10 ml of PBS for counting.</li>
	<li>Take 20 &#956;l of blastospores in 1.5 ml microcentrifuge tubes, add 20 &#956;l of the 2X paraformaldehyde and incubate at RT for 15-20 min.&#160;Count the fixed blastospores using the hemocytometer under the microscope. 
	NOTE: Paraformaldehyde is carcinogenic. Open the undiluted solution only in the fume hood.</li>
	<li>In the meantime, repeat washing the blastospores at least twice, by centrifuging them in PBS, and pelleting the blastospores . Keep the pellets in 15 ml tubes at RT, in the ABSL1 hood, ready for infection.</li>
	<li>Leave some sterile PBS at RT for resuspending the blastospores for infection.</li>
	<li>After counting, add sterile PBS to the blastospore pellet to adjust the yeast blastospore cell numbers to 2 x108 of yeast cells/ml. This is the blastospore suspension that will be used to infect the mice. 
	NOTE: Perform all the steps aseptically.</li>
</ol>
4. Mice Infection (3-5 Days after Cell Transfer)
NOTE: The basic infection procedure is performed as described previously19,23-25.
<ol>
	<li>Weigh the Rag-1-/- mice that received PBS or the cells three days earlier.</li>
	<li>Calculate the dose of anesthetic agents using their body weight. Anesthetize the mice by administering ketamine/xylazine mixture (16.1 mg/ml and 1.6 mg/ml), using 25 G needles on 1 ml tuberculin syringes, by intraperitoneal injection.
	<ol>
		<li>Administer 50 &#181;l per 10 grams of body weight. (i.e., 0.8 mg of ketamine and 0.08 mg of xylazine/10 g of body weight or 80 mg of ketamine and 8 mg of xylazine per kg of body weight respectively). Observe for toe pinch response every 15 min after anesthesia. 
		NOTE: This dosage will induce 60-90 min of anesthesia, which is enough for the infection procedure.</li>
		<li>Apply the ophthalmic lubricant ointment in the eyes of the mice to prevent the corneas from drying out. As the eye lubricant may dry out, repeat ophthalmic lubrication every 45 min.</li>
	</ol>
	</li>
	<li>Inject 1 ml of saline (0.9% NaCl) subcutaneously on the back adjacent to the forelimb, to help rehydration of the mice during anesthesia.</li>
	<li>Obtain a new, clean cage. Follow the infection procedure one mouse at a time, placing each mouse into the new cage once infected. Perform the PBS/sham infection first,and then proceed to the Candida infection groups.</li>
	<li>Pick up the anesthetized mouse and open the mouth wide to reveal the base of the tongue.
	<ol>
		<li>Place a 3 mm diameter cotton ball saturated with 50 &#181;l of PBS or blastospore suspension, sublingually in the oral cavity for 90 min. Flip the mice every 15 min front and back to prevent lung congestion, ensuring that the cotton balls don&#39;t move.</li>
	</ol>
	</li>
	<li>Set up a timer for every mouse to ensure 90 min of Sham or Candida inoculation in the oral cavity.</li>
	<li>Keep them in a cage under the heat lamp (4 feet away), and each mouse on heat gel pads.</li>
	<li>Make sure that the tongue is withdrawn inside and away from the teeth, to avoid teeth lacerating the tongue.</li>
	<li>At the end of 90 min, remove the cotton ball from the mouth of the mouse. Watch for any mouse that may recover from anesthesia sooner than 75 minutes. In such a case, anesthetize them again with ketamine (40 mg/kg) only.</li>
</ol>
5. Post Procedure Monitoring (during the 90 min Anesthesia)
<ol>
	<li>Use heat gel pads during the 90 min anesthesia.
	<ol>
		<li>To maintain the body temperature and to prevent suffocation, do not allow mice to recover on the regular corn-cob mouse bedding.</li>
	</ol>
	</li>
	<li>After the recovery from anesthesia, administer an additional 1 ml of sterile 0.9% NaCl subcutaneously in two locations on the back.</li>
	<li>Keep up to five PBS (sham) inoculated mice per cage. House only 1-2 infected mice per cage.</li>
	<li>Fill out the procedure card with initials every day after the procedure to note down the changes in the body weight, grooming habits and overall health.</li>
</ol>
6. Assessing the Inflammation
6.1) Weight loss
<ol>
	<li>Weigh the mice every day during the infection, starting on the day prior to infection procedure. 
	NOTE: Typically, the immunodeficient mice injected with Th17 cells and with no Tregs succumb to 20-30% weight loss due to increased fungal burden19 and exacerbated inflammation.</li>
</ol>
6.2) Histology scoring of the tongue
<ol>
	<li>Sacrifice the mice by CO2 asphyxiation followed by cervical dislocation.</li>
	<li>Open the jaws and dissect out the tongue with scissors and forceps. Use blunt forceps to hold the tongue, and using the scissors reach out to the back of the mouth to incise the back end of the tongue.</li>
	<li>For immunocytochemical hematoxylin and eosin (H&#38;E) staining of the tongue tissues, rinse the tongue tissues with ice cold PBS. Add 5 ml of 10% formalin for 2-3 tongues and fix them O/N in 15 ml tubes.
	<ol>
		<li>The next day, remove the formalin and immerse the tissues in 5 ml of 70% ethanol to prevent hyper-fixation. Send them out to commercial service to continue with paraffin embedding, sectioning and staining of paraffin sections. 
		NOTE: Commercial histology service is used to perform these steps.</li>
	</ol>
	</li>
	<li>Once the slides are back from the commercial histology service, grade the inflammation by observing the tissue sections under a light microscope.
	<ol>
		<li>Score from 0 to 5, with 0 being no inflammation, and 5 being the most severe inflammation. Score the inflammation using Table 1.</li>
	</ol>
	</li>
</ol>
6.3) Cytokine production by Th17 cells
NOTE: Excessive TNF-&#945; production is one of the readouts for excessive immunopathology. When mice are adoptively transferred with Th17 cells only, it causes immunopathology that is associated with excessive TNF-&#945; production in Th17 cells.
<ol>
	<li>Collect a single cell suspension from spleen, cervical lymph nodes, axillary lymphnodes, and tongue, using previously described methods19,26.</li>
	<li>Restimulate the cells with phorbol myristate acetate (PMA) (50 ng/ml) and Ionomycin (500 ng/ml) for 4 hr with Brefeldin A (10 &#181;g/ml) added in the last 2 hr. Wash the cells with PBS and fix them using a commercial Fixation/permeabilization kit according to manufacturer&#8217;s instructions.</li>
	<li>Perform intra cellular cytokine staining using the fluorochrome conjugated anti-TNF-&#945;, anti-IL-17A and ROR-&#947;t antibodies as described previously19.</li>
	<li>Briefly, resuspend the cells in the 1X permeabilization buffer with the cocktail of anti-TNF-&#945;, anti-IL-17A and ROR-&#947;t antibodies, each antibody at 2 - 3 &#181;g/ml final concentration.</li>
	<li>Incubate the cells for 1 hr at RT.</li>
	<li>After the incubation, wash the cells with 1X permeabilization buffer.</li>
	<li>Resuspend the cell pellet in 500 &#181;l of PBS with 0.5% bovine serum albumin for flow cytometry analysis.</li>
</ol>

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The authors declare that they have no competing financial interests.

This model is based on inducing oral C. albicans infection dependent Th17 inflammation. Because of the absence of Tregs, the Th17 cell induced inflammation is unrestrained and leads to poorly resolved immunopathology. In vitro derived na&#239;ve CD4 cells polarized as Th17 cells were used for the adoptive transfer. 40 - 50% of the cultured CD4+ cells show detectable IL-17A expression around day 3 (Th17 cells), and therefore were used for the injection in mice. The major advantage of the model is that Th17 cells cause infection specific immunopathology that can be efficiently ameliorated with Treg injection. Thus the model can be employed to test immunomodulation strategies with Treg injection as a positive control. Inflammation is easily assessed based on the weight loss, histopathological scoring and pro-inflammatory cytokine production by the Th17 cells of the infected mice.
After the adoptive transfer of Th17 cells, they migrated to secondary lymphoid organs and various tissues including the tongue, the primary site of infection. After the infection, other inflammatory cells were also recruited to the tongue to clear the infection. However, without Treg mediated immunomodulation, Th17 cells themselves did not resolve the infection but caused heightened immunopathology. Co-transfer of Tregs completely resolved the inflammation. Interestingly, mice with exacerbated inflammation in the absence of Tregs, also showed increased fungal burden. Our previous report showed that this was due to reduced IL-17A production in mice, compared to those with Tregs. Our current experiments support the idea that it may also be due to increased TNF-&#945; that worsened the inflammation, possibly by increasing epithelial cell apoptosis and increased fungal burden28. Considering the immunoprotective effects of IL-17A at the mucosa, we believe that inflammatory pathology that we observe with increasing fungal burden is not due to IL-17A produced by Th17 cells or lack of host resistance. It is caused due to TNF-&#945; and possibly other pro-inflammatory cytokines produced by injected Th17 cells. This can be validated by the observation that Rag-/- mice devoid of Th17 cells show only minimal inflammation and subsequent resolution of infection and only those that received Th17 cells succumbed to severe weight loss (Figure 1). Consistent to this data, it has been also previously shown that Rag-/- mice clear the primary OPC infection without much immunopathology27. Under these conditions, compensatory mechanisms dependent on IL-17A producing innate immune cells have been shown to clear the infection in Rag-/- mice17,29,30. Taken together, although IL-17A produced by Th17 cells and neutrophil recruitment are playing a protective role at initial phases of infection, excessive production of TNF-&#945; and other cytokines by Th17 cells, and the continued presence of neutrophils causes exacerbated immunopathology. The roles of pro-inflammatory cytokines besides TNF-&#945; produced by Th17 cells remain to be investigated in the context of immunopathology.
The major limitation of the model is the question whether it is physiologically relevant to human OPC. Although Th17 cells are shown to be pathological mediators in several oral diseases, whether chronic activation of Th17 cells is pathogenic in OPC remain to be investigated. With recent findings implying the role of C. albicans in inflammation and cancer, Th17 immunopathology in the oral cavity is an active field of investigation31. Thus the model that is described here can be used to more carefully study specific roles of Th17 cells and how they interact with innate immune cells, giving detailed insights in to oral immunological diseases and oral cancer.
The critical step in the technique is the appropriate recruitment and expansion of the adoptively transferred Th17 cells. This is highly dependent on the viability and IL-17A production of the in vitro polarized Th17 cells before the transfer. It is best to test their viability and cytokine production by flow cytometry analyses19. Proper execution of the Th17 cell injection and mice infection will lead to infection dependent Th17 immunopathology. This model can be applied to test strategies to thwart Th17 immunopathology and oral inflammation in the context of other infections as well. Also, using this model, one can perform secondary re-infections and study the role of Th17 cells in exacerbating immunopathology in the context of chronic infections. As this model involves immunodeficient mice, it may be very relevant to oral dysbiosis seen in AIDS and PID patients, who suffer from recurring chronic Candida infections.

Oral infections and inflammation have been related to cancer and cardiovascular diseases, and have dramatic impact on overall human health2,3. Opportunistic infections and inflammation caused by C. albicans are associated with primary immunodeficiencies (PID)4,5, inflammatory disorders such as periodontitis 6,7, Sjogren&#8217;s syndrome, and salivary gland disease8,9, as well as oral squamous cell carcinoma 10-12. C. albicans is a dimorphic commensal fungus that colonizes the mouths of 60% of healthy humans asymptomatically, yet it is the most common fungal pathogen causing infections when the host defense is weakened13-15. It causes recurring and chronic infections and inflammation in patients with AIDS and PID, and also in other immunocompromised individuals. As a commensal, its colonization load is associated with the change in the diversity of the overall oral microbiome16. As a pathogen it causes several forms of oropharyngeal candidiasis such as acute pseudomembranous, acute atrophic, chronic atrophic, chronic hypertrophic/hyperplastic, and angular cheilitis. 
Protection against C. albicans is determined not only by host immune resistance, but also by the ability to appropriately control Candida-induced immunopathology. Although commensals such as C. albicans contribute to modulation and exacerbation of other oral inflammatory conditions, the mechanisms by which dysbiosis occur during opportunistic infections are unclear. Besides the known role of adaptive Th17 cells in memory response to C. albicans17, their role in initiation and perpetuation of inflammation pathology during chronic infections remain unclear. Furthermore, oral inflammatory diseases such as Sjogren&#8217;s syndrome and periodontitis are associated with Th17 mediated pathology. Interestingly, these diseases are also strongly associated with frequent OPC. However, the interactions among Th17 cells, oral immunopathology of OPC and other oral inflammatory diseases are unstudied. 
Although mouse models of primary and secondary infection of oral candidiasis are available, a mouse model to study Candida infection associated Th17 inflammation, especially in the context of immunodeficiency is unavailable. This study presents a method for establishing oral Th17 inflammation associated with oral Candida infection in mice. Candida infection in mice is characterized by fungal lesions, inflammation in the tongue, decreased food intake, weight loss and eventually a moribund state. Oral pathology resembles chronic candidal infection lesions, as well as epithelial dysplasia in mouse oral cancer models12,18.

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		<tr height="25">
			<td height="25" style="height:25px;width:380px;">CAF-2</td>
			<td style="width:411px;">University of Pittsburgh (Sarah Gaffen)</td>
			<td style="width:119px;">-</td>
			<td style="width:380px;">Candida culture</td>
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			<td height="26" style="height:26px;">U-bottom 96 well plates&#160;</td>
			<td style="width:411px;">Fisher</td>
			<td style="width:119px;">055588</td>
			<td>Used for cell culture</td>
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			<td style="width:411px;">eBiosciences</td>
			<td style="width:119px;">16-0031-85</td>
			<td>Polarization of cells to Th17 conditions</td>
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			<td style="width:411px;">eBiosciences</td>
			<td style="width:119px;">16-0281-85</td>
			<td>Polarization of cells to Th17 conditions</td>
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			<td height="20" style="height:20px;">m-IL-6</td>
			<td style="width:411px;">Bio Basic</td>
			<td style="width:119px;">RC232</td>
			<td>Polarization of cells to Th17 conditions</td>
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			<td height="20" style="height:20px;">h-TGF-b&#160;</td>
			<td style="width:411px;">R&#38;D</td>
			<td style="width:119px;">240-B</td>
			<td>Polarization of cells to Th17 conditions</td>
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			<td style="width:411px;">eBiosciences</td>
			<td style="width:119px;">16-7311-85</td>
			<td>Polarization of cells to Th17 conditions</td>
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			<td style="width:411px;">eBiosciences</td>
			<td style="width:119px;">16-7041-85</td>
			<td>Polarization of cells to Th17 conditions</td>
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			<td height="20" style="height:20px;width:380px;">&#945;-IL17A ef660</td>
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			<td>50-7177-82</td>
			<td>Used for cell culture - 1:50</td>
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			<td height="20" style="height:20px;width:380px;">&#945;-TNFa-PE-Cy7</td>
			<td>eBiosciences</td>
			<td>25-7423-41</td>
			<td>Used for cell culture - 1:100</td>
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			<td height="20" style="height:20px;width:380px;">&#945;-RORgt PE&#160;</td>
			<td>eBiosciences</td>
			<td>12-6981-82</td>
			<td>Used for cell culture - 1:50</td>
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		<tr height="25">
			<td height="25" style="height:25px;">YNB w/o amino acids)/Peptone/Dextrose broth medium&#160;</td>
			<td style="width:411px;">Bio Basic</td>
			<td style="width:119px;">S507.SIZE</td>
			<td>Mediium for candida growth</td>
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		<tr height="22">
			<td height="22" style="height:22px;">Shaker incubator&#160;</td>
			<td style="width:411px;">New Brunswick Scientific</td>
			<td style="width:119px;">Innova 4300</td>
			<td>Incubation growth for candida</td>
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			<td height="24" style="height:24px;">15 ml tubes</td>
			<td style="width:411px;">Bio Basic</td>
			<td style="width:119px;">BT888-SY</td>
			<td>Used for cell culture and candida growth</td>
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			<td height="22" style="height:22px;">50 ml tubes</td>
			<td style="width:411px;">Bio Basic</td>
			<td style="width:119px;">CT 788-YS</td>
			<td>Used for cell culture and candida growth</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Table top Centrifuge</td>
			<td style="width:411px;">VWR International LLC</td>
			<td style="width:119px;">82017-654</td>
			<td>For pelleting candida -900 g</td>
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		<tr height="20">
			<td height="20" style="height:20px;">Allegra Centrifuge</td>
			<td style="width:411px;">Beckman Coulter</td>
			<td style="width:119px;">392302</td>
			<td>Cell culture - 480 g</td>
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		<tr height="25">
			<td height="25" style="height:25px;">1.5 ml eppendorf tubes</td>
			<td style="width:411px;">Bio Basic</td>
			<td style="width:119px;">BT620-NS</td>
			<td>Preparing final concentration of candida</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;">2x paraformaldehyde</td>
			<td style="width:411px;">Electron Microscopy Sciences</td>
			<td style="width:119px;">15710</td>
			<td>Fixing candida for count</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hemocytometer</td>
			<td style="width:411px;">VWR International LLC</td>
			<td style="width:119px;">15170-172</td>
			<td>Counting cells</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">PBS - Phosphate Buffered Saline</td>
			<td style="width:411px;">Bio Basic</td>
			<td style="width:119px;">PD8117</td>
			<td>Preparation of buffers</td>
		</tr>
		<tr height="23">
			<td height="23" style="height:23px;">Ketamine/xylazine&#160;</td>
			<td style="width:411px;">Case Western Reserve University - Animal Resource Center</td>
			<td style="width:119px;">-</td>
			<td>Obtained from ARC approved protocol for anesthesia</td>
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		<tr height="20">
			<td height="20" style="height:20px;">Ophthalmic lubricant ointment&#160;</td>
			<td style="width:411px;">Allergan</td>
			<td style="width:119px;">-</td>
			<td>Eye ointment for animals to prevent dryness</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;">Saline (0.9% NaCl)</td>
			<td style="width:411px;">G Biosciences</td>
			<td style="width:119px;">786-561</td>
			<td>Administerd to animals to prevent dehydration</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">3-mm-diameter cotton wool ball&#160;</td>
			<td style="width:411px;">VWR International LLC</td>
			<td style="width:119px;">BP7603</td>
			<td>3 mm balls for candida infection</td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;">Heat gel pads</td>
			<td style="width:411px;">Case Western Reserve University - Animal Resource Center</td>
			<td style="width:119px;">-</td>
			<td>for maintaining the body temperaturre and fast recovery</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hematoxylin and Eosin staining</td>
			<td style="width:411px;">Histoserv - MD</td>
			<td style="width:119px;">-</td>
			<td>Tissue histology</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;">10% formalin&#160;</td>
			<td style="width:411px;">Electron Microscopy Sciences</td>
			<td style="width:119px;">JC1111/MC</td>
			<td>Tissue histology</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">70% ethanol&#160;</td>
			<td style="width:411px;">VWR International LLC</td>
			<td style="width:119px;">97064-490</td>
			<td>Sterilization purpose</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">PMA - Phorbol 12-myristate 13-acetate</td>
			<td style="width:411px;">Sigma-Aldrich</td>
			<td style="width:119px;">P1585-1MG</td>
			<td>Restimulation of cells</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Ionomycin</td>
			<td style="width:411px;">Life Technologies</td>
			<td style="width:119px;">124222 1mg</td>
			<td>Restimulation of cells</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Fixation permeabilization kit</td>
			<td style="width:411px;">eBiosciences</td>
			<td style="width:119px;">E16913-106</td>
			<td>Fixing cells for Flow cytometry</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:380px;">Tuberculin syringes</td>
			<td>BD Biosciences</td>
			<td align="right">309659</td>
			<td>Mice injection</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">25 G x 3/8 needles</td>
			<td>BD Biosciences</td>
			<td align="right">309626</td>
			<td>Mice injection</td>
		</tr>
		<tr height="39">
			<td height="39" style="height:39px;">Rag1 -/- mice</td>
			<td style="width:411px;">Jackson laboratories</td>
			<td style="width:119px;">Stock no: 002216</td>
			<td>Recipient mice</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">CD45.1 congenic mice</td>
			<td style="width:411px;">Jackson laboratories</td>
			<td style="width:119px;">Stock no:002014&#160;</td>
			<td>Donor Th17 cells</td>
		</tr>
		<tr height="39">
			<td height="39" style="height:39px;width:380px;">CB17-SCID mice</td>
			<td style="width:411px;">Jackson laboratories</td>
			<td style="width:119px;">Stock no: 001303</td>
			<td>Recipient mice</td>
		</tr>
		<tr height="39">
			<td height="39" style="height:39px;width:380px;">Balb/c mice</td>
			<td style="width:411px;">Jackson laboratories</td>
			<td style="width:119px;">Stock no: 000651</td>
			<td>Donor Th17 cells</td>
		</tr>
	</tbody>
</table>

th17 inflammation model of oropharyngeal candidiasis in immunodeficient mice

Oropharyngeal Candidiasis (OPC) disease is caused not only due to the lack of host immune resistance, but also the absence of appropriate regulation of infection-induced immunopathology. Although Th17 cells are implicated in antifungal defense, their role in immunopathology is unclear. This study presents a method for establishing oral Th17 immunopathology associated with oral candidal infection in immunodeficient mice. The method is based on reconstituting lymphopenic mice with in vitro cultured Th17 cells, followed by oral infection with Candida albicans (C. albicans). Results show that unrestrained Th17 cells result in inflammation and pathology, and is associated with several measurable read-outs including weight loss, pro-inflammatory cytokine production, tongue histopathology and mortality, showing that this model may be valuable in studying OPC immunopathology. Adoptive transfer of regulatory cells (Tregs) controls and reduces the inflammatory response, showing that this model can be used to test new strategies to counteract oral inflammation. This model may also be applicable in studying oral Th17 immunopathology in general in the context of other oral diseases.

In this model, both the Candida-infected mice and uninfected mice in Rag-1-/- immunodeficient background were adoptively transferred with Th17 cells 3-5 days prior to the infection. A total of 10-12 mice were used for the experiments, with 2 mice in each Sham infected groups, and 4-5 in each of the Candida infected groups. Naive cells were derived from congenic Thy1.1 or CD45.1 mice, so that injected Th17 cells were tracked in vivo using Thy1.1 or CD45.1 staining respectively (Figure 1A). Co-transferred Tregs were derived from CD45.2 mice to distinguish them from CD45.1 Th17 cells. For some experiments, C.B-17 Thy1.2 scid recipient mice, Th17 donor cells obtained from Thy1.1 Balb/C mice and Tregs obtained from congenic Thy1.2 mice were used. Only Candida-infected mice, but not the uninfected mice exhibited the recruitment and expansion of reconstituted CD45.1+ Th17 cells in the CLN, the draining lymph nodes. This result demonstrates that the fungus Th17 specific response is initiated in tongue draining lymph nodes (Figure 1A). The results represent data from one mouse in each group.
Only in the mice that are co-transferred with Tregs, Foxp3+ CD45.1 negative CD4+ cells were detected in the CLN. This shows that the injected Tregs were also recruited to the site of infection (Figure 1B). The results represent data from one mouse in each group. Whereas infected Rag-1-/- lose weight and recovered after 4 days of infection, cortisone immunosuppressed mice did not recover but further lost weight, as shown previously27. Both the groups of mice that received Th17 cells in the presence or absence of Tregs lost weight initially. However, the mice that received Tregs recovered from weight loss and resolved the infection. 2 mice were used in the Sham infected group, and 4 in each Candida infected group. There were 3 mice in cortisone group. The mice that received Th17 cells only, lost weight progressively (Figure 2)19. Some of the mice in that group had to be euthanized. These results show the average of the weights of all the mice in that group. Although neutrophils are required for the initial clearance of the infection, their continuous presence and recruitment in the tissue is a sign of unresolved inflammation. Therefore neutrophil infiltration was examined in the infected tongue, by determining the expression of a neutrophil marker, Gr-1, at later time points such as day-7 after infection. Mice that received Th17 cells only, had higher inflammatory infiltrates (Figure 3A), including Gr-1+ neutrophils even day-4 after infection, compared to the mice injected with Tregs (Figure 3B). These results showed that in the presence of Tregs, mice resolved the inflammation more efficiently and recovered from the infection.
On day 7 after infection, spleen (SPLN), CLN and the tongue tissues were isolated, and single cell suspensions were made for flow cytometry analyses. CLN revealed increased CD45.1 Th17 cells (Figure 1) and heightened TNF-&#945; production (Figure 4A, 4B) in mice that received Th17 cells only. On the other hand, Treg recipients showed decreased frequency of Th17 cells and reduced TNF-&#945; production by Th17 cells (Figure 1 &#38; 4A, 4B). In these experiments, data from CLN of a single mouse, and tongue tissues harvested and pooled from 2 mice are shown. Although at early time-points IL-17A production was higher in Treg recipients19, at later time points in both the groups, IL-17A production by Th17 cells was minimal (data not shown). Periodic Acid Schiff&#8217;s staining of the tongue showed increased fungal hyphae in mice that received Th17 cells only, whereas mice that received Tregs as well cleared the fungus on day-5 and day-7 after infection (Figure 5). Moreover, histopathology scoring of the tongue inflammation also showed reduced inflammation scores in mice that received Tregs, compared to mice that received only Th17 cells (Figure 6). Scoring the inflammation was based on the tongue histopathological parameters such as, presence of papillae, the intactness of the superficial epithelial layer, visible yeast or hyphae, invading hyphae indicating non-resolving infection, thickening of basal layer (indicative of ongoing tissue repair), and the presence of infiltrating immune cells (neutrophils and Th17 cells). These results demonstrated that injection of Th17 cells did not directly reduce infection but increased the fungal burden and immunopathology caused by primary C. albicans infection, whereas co-transfer of Tregs ameliorated immunopathology.
<img alt="Figure 1" src="/files/ftp_upload/52538/52538fig1highres.jpg" /> 
Figure&#160;1. Injected Th17 cells and Treg cells recruit and expand in the draining lymph nodes (CLN) of the C. albicans infected mice. (A) Rag-1-/- CD45.2 mice were reconstituted with Th17 cells or Th17 + Treg cells that were polarized under Th17 conditions for 5 days. Th17 cells were obtained from CD45.1 congenic mice and Treg cells were obtained from CD45.2 mice. Some mice did not receive any cells (Sham or Candida + PBS). Recipient mice in each group were infected with sham controls or with C. albicans. On day 5 after infection, CLN were isolated to make a single cell suspension and track the injected CD45.1 expressing Th17 cells by flow cytometry (gated on all leukocytes in FSC, SSC scatter). (B) Rag-1-/- CD45.2 mice were reconstituted with Th17 cells or Th17 + Treg cells as in &#8220;A&#8221; and infected with C. albicans. CLN were isolated to make a single cell suspension and measure CD45.1 and intracellular Foxp3 expression by flow cytometry (gated on all CD4 cells). The Treg gates in the plots show the CD45.1 negative, Foxp3+ CD4+ cells. <a href="https://www.jove.com/files/ftp_upload/52538/52538fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" src="/files/ftp_upload/52538/52538fig2highres.jpg" /> 
Figure&#160;2. Injected Th17 cells cause weight loss in C. albicans infected mice and co-administration of Tregs improves recovery from weight loss. SCID CB-17 mice were reconstituted with Th17 cells or Th17 + Treg cells as in Figure 1A. 3 days later, the recipient mice were infected with C. albicans. Some mice in each group were infected with sham controls. Immunosuppressed mice received cortisone acetate (Cort) injection. The percent weight change in mice reconstituted with indicated cells and infected with C.albicans, with respect to d-1 (one day prior to infection) is shown. Data are normalized relative to the weight data from uninfected (Sham + PBS) mice. <a href="https://www.jove.com/files/ftp_upload/52538/52538fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 3" src="/files/ftp_upload/52538/52538fig3highres.jpg" /> 
Figure&#160;3. Injected Th17 cells cause tongue immunopathology in C. albicans infected mice and co-administration of Tregs reduces the immunopathology. Histological evaluation of the tongues of the C. albicans infected mice. Mice were reconstituted with indicated cells and infected as in Figure 1A. On day 5 after infection, tongues were isolated from mice. (A) Sagittal sections of the tongues were stained with H&#38;E to assess inflammation and infiltration (IF) of the immune cells. (Pa) and (Ep) denote papillae and the epithelial layer of the tongue respectively. Microscopic images of the slides viewed at50X magnification. (B) Histological immunostaining for Gr-1 neutrophil marker using anti Gr-1 antibody (Clone: 1A8-Ly6g) in the tongue sections on day 5 after infection (brown, denoted by IF). Microscopic images of the slides viewed at 100X magnification are shown. <a href="https://www.jove.com/files/ftp_upload/52538/52538fig3large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 4" src="/files/ftp_upload/52538/52538fig4highres.jpg" /> 
Figure&#160;4. Co-administration of Tregs reduces TNF-&#945; in injected Th17 cells. (A) Rag-1-/- CD45.2 mice were reconstituted with Th17 cells or Th17 + Treg cells and infected with C. albicans as in Figure 1A. On day 5 after infection, CLN and tongue tissues were isolated to make a single cell suspension. These cells were restimulated with PMA and Ionomycin before intracellular staining and flow cytometry analyses. Flow cytometric contour plots of intracellular ROR-&#947;t and TNF- &#945; expression of the Th17 cells are shown (gated on CD4+ cells). (B) Statistical representation of the percentage of TNF&#945;positive cells from experiments performed as in &#8220;A&#8221;. Data represent 4 mice in uninfected group, and 6 mice in each infected group, and are pooled from two independent experiments. <a href="https://www.jove.com/files/ftp_upload/52538/52538fig4large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 5" src="/files/ftp_upload/52538/52538fig5highres.jpg" /> 
Figure&#160;5. Increased immunopathology is also associated with increased fungal burden in C. albicans infected mice. C.B-17 scid mice were reconstituted with Balb/C Th17 cells, or Th17 + Treg cells as in Figure1A, and were infected with C. albicans. Histological evaluation of the tongue from infected mice is shown. On day 7 after infection, tongues were harvested and stained with periodic Acid Schiff&#8217;s (PAS) to assess fungal lesions, inflammation and infiltration (IF) of cells, and to detect fungus(Ca). The slides were viewed at100X magnification. <a href="https://www.jove.com/files/ftp_upload/52538/52538fig5large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 6" src="/files/ftp_upload/52538/52538fig6highres.jpg" /> 
Figure&#160;6. Tregs ameliorate immunopathology in C. albicans infected mice. C.B-17 scid mice were reconstituted with Balb/C Th17 cells, or Th17 + Treg cells as in Figure 1A, and were infected with C. albicans. Statistical representation of the mean histological scores of the tongues from infected mice assessed as in Figure 5. <a href="https://www.jove.com/files/ftp_upload/52538/52538fig6large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<table border="0" cellpadding="0" cellspacing="0" fo:keep-together.within-page="always">
	<tbody>
		<tr>
			<td>Score</td>
			<td>Characteristics</td>
		</tr>
		<tr>
			<td>0</td>
			<td>0 &#8211; no visible yeast or hyphae, intact superficial epithelium on dorsal surface of tongue, papillae clearly present and undamaged (may or may not be infiltrating mononuclear cells within the tissue), no thickening of basal layer, no infiltrating immune cells.</td>
		</tr>
		<tr>
			<td>1</td>
			<td>1 - no visible yeast or hyphae, ragged or slightly damaged superficial epithelium, papillae clearly present with minimal damage and infrequent infiltrating immune cells.</td>
		</tr>
		<tr>
			<td>2</td>
			<td>2 - papillae reduced but present with damage, thickening of basal layer and frequent infiltrating immune cells.</td>
		</tr>
		<tr>
			<td>3</td>
			<td>3 - occasional clusters of visible yeast and invading hyphae, evidence of damaged papillae, occasional lesions of damaged epithelium, thickening of basal layer and and small clusters of infiltrating immune cells.</td>
		</tr>
		<tr>
			<td>4</td>
			<td>4 - frequent clusters of visible yeast and invading hyphae, evidence of damaged papillae, frequent lesions of damaged epithelium, minimal infiltration of immune cells, thickening of basal layer and frequent clusters of infiltrating immune cells.</td>
		</tr>
		<tr>
			<td>5</td>
			<td>5 - widespread evidence of invading hyphae, extensively damaged epithelium across the dorsal surface, large infiltration of immune cells, few or no detectable papillae, thickening of basal layer and highly frequent and large clusters of infiltrating immune cells.</td>
		</tr>
	</tbody>
</table>
Table 1: Histological Scoring Values

Watch this Scientific Journal Video about Th17 Inflammation Model of Oropharyngeal Candidiasis in Immunodeficient Mice at JoVE.com

Th17 Inflammation Model of Oropharyngeal Candidiasis in Immunodeficient Mice

Although Candida infection models are available to study host immune resistance, a model to study T cell mediated immunopathology in the context of Candida infection is absent. Here we describe a method to establish Th17 immunopathology associated with oral Candida infection in immunodeficient mice.

Oropharyngeal Candidiasis (OPC) disease is caused not only due to the lack of host immune resistance, but also the absence of appropriate regulation of ...

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Nanyang Technological University

Research

JoVE Journal

Medicine

9.9K Views.  Case Western Reserve University. Although Candida infection models are available to study host immune resistance, a model to study T cell mediated immunopathology in the context of Candida infection is absent. Here we describe a method to establish Th17 immunopathology associated with oral Candida infection in immunodeficient mice. 

Video: Th17 Inflammation Model of Oropharyngeal Candidiasis in Immunodeficient Mice

Functional Assessment of Intestinal Motility and Gut Wall Inflammation in Rodents: Analyses in a Standardized Model of Intestinal Manipulation

Inflammation of the gastrointestinal tract is a common reason for a variety of human diseases. Animal research models are critical in investigating the complex cellular and molecular of intestinal pathology. Although the tunica mucosa is often the organ of interest in many inflammatory diseases, recent works demonstrated that the muscularis externa (ME) is also a highly immunocompetent organ that harbours a dense network of resident immunocytes.1,2 These works were performed within the standardized model of intestinal manipulation (IM) that leads to inflammation of the bowel wall, mainly limited to the ME. Clinically this inflammation leads to prolonged intestinal dysmotility, known as postoperative ileus (POI) which is a frequent and unavoidable complication after abdominal surgery.3 The inflammation is characterized by liberation of proinflammatory mediators such as IL-64 or IL-1&beta; or inhibitory neurotransmitters like nitric oxide (NO).5 Subsequently, tremendous numbers of immunocytes extravasate into the ME, dominated by polymorphonuclear neutrophils (PMN) and monocytes and finally maintain POI.2 Lasting for days, this intestinal paralysis leads to an increased risk of aspiration, bacterial translocation and infectious complications up to sepsis and multi organ failure and causes a high economic burden.6
In this manuscript we demonstrate the standardized model of IM and in vivo assessment of gastrointestinal transit (GIT) and colonic transit. Furthermore we demonstrate a method for separation of the ME from the tunica mucosa followed by immunological analysis, which is crucial to distinguish between the inflammatory responses in these both highly immunoactive bowel wall compartments. All analyses are easily transferable to any other research models, affecting gastrointestinal function.

Postoperative ileus (POI) is a complication of abdominal surgery leading to increased morbidity and a prolonged hospital stay. Because prophylactic or therapeutic strategies are lacking intensified research is necessary. Therefore we established a standardized and feasible mouse model to investigate the pathophysiology of POI and to study potential therapeutic options.

Inflammation of the gastrointestinal tract is a common reason for a variety of human diseases. Animal research models are critical in investigating the ...

Generation of Subcutaneous and Intrahepatic Human Hepatocellular Carcinoma Xenografts in Immunodeficient Mice

In vivo experimental models of hepatocellular carcinoma (HCC) that recapitulate the human disease provide a valuable platform for research into disease pathophysiology and for the preclinical evaluation of novel therapies. We present a variety of methods to generate subcutaneous or orthotopic human HCC xenografts in immunodeficient mice that could be utilized in a variety of research applications. With a focus on the use of primary tumor tissue from patients undergoing surgical resection as a starting point, we describe the preparation of cell suspensions or tumor fragments for xenografting. We describe specific techniques to xenograft these tissues i) subcutaneously; or ii) intrahepatically, either by direct implantation of tumor cells or fragments into the liver, or indirectly by injection of cells into the mouse spleen. We also describe the use of partial resection of the native mouse liver at the time of xenografting as a strategy to induce a state of active liver regeneration in the recipient mouse that may facilitate the intrahepatic engraftment of primary human tumor cells. The expected results of these techniques are illustrated. The protocols described have been validated using primary human HCC samples and xenografts, which typically perform less robustly than the well-established human HCC cell lines that are widely used and frequently cited in the literature. In comparison with cell lines, we discuss factors which may contribute to the relatively low chance of primary HCC engraftment in xenotransplantation models and comment on technical issues that may influence the kinetics of xenograft growth. We also suggest methods that should be applied to ensure that xenografts obtained accurately resemble parent HCC tissues.

Human tumor xenografts in immunodeficient mice are valuable tools to study cancer biology. Specific protocols to generate subcutaneous and intrahepatic xenografts from human hepatocellular carcinoma cells or tumor fragments are described. Liver regeneration induced by partial hepatectomy in recipient mice is presented as a strategy to facilitate intrahepatic engraftment.

In  vivo experimental models of hepatocellular carcinoma (HCC) that recapitulate  the human disease provide a valuable platform for research into disease  ...

Combined In vivo Optical and &#181;CT Imaging to Monitor Infection, Inflammation, and Bone Anatomy in an Orthopaedic Implant Infection in Mice

Multimodality imaging has emerged as a common technological approach used in both preclinical and clinical research. Advanced techniques that combine in vivo optical and &#956;CT imaging allow the visualization of biological phenomena in an anatomical context. These imaging modalities may be especially useful to study conditions that impact bone. In particular, orthopaedic implant infections are an important problem in clinical orthopaedic surgery. These infections are difficult to treat because bacterial biofilms form on the foreign surgically implanted materials, leading to persistent inflammation, osteomyelitis and eventual osteolysis of the bone surrounding the implant, which ultimately results in implant loosening and failure. Here, a mouse model of an infected orthopaedic prosthetic implant was used that involved the surgical placement of a Kirschner-wire implant into an intramedullary canal in the femur in such a way that the end of the implant extended into the knee joint. In this model, LysEGFP mice, a mouse strain that has EGFP-fluorescent neutrophils, were employed in conjunction with a bioluminescent Staphylococcus aureus strain, which naturally emits light. The bacteria were inoculated into the knee joints of the mice prior to closing the surgical site. In vivo bioluminescent and fluorescent imaging was used to quantify the bacterial burden and neutrophil inflammatory response, respectively. In addition, &#956;CT imaging was performed on the same mice so that the 3D location of the bioluminescent and fluorescent optical signals could be co-registered with the anatomical &#956;CT images. To quantify the changes in the bone over time, the outer bone volume of the distal femurs were measured at specific time points using a semi-automated contour based segmentation process. Taken together, the combination of in vivo bioluminescent/fluorescent imaging with &#956;CT imaging may be especially useful for the noninvasive monitoring of the infection, inflammatory response and anatomical changes in bone over time.

Combined In vivo Optical and  &#181;CT Imaging to Monitor Infection, Inflammation, and Bone Anatomy in an Orthopaedic Implant Infection in Mice

Combined optical and &#956;CT imaging in a mouse model of orthopaedic implant infection, utilizing a bioluminescent engineered strain of Staphylococcus aureus, provided the capability to noninvasively and longitudinally monitor the dynamics of the bacterial infection, as well as the corresponding inflammatory response and anatomical changes in the bone.

Multimodality imaging has emerged as a common technological approach used in both preclinical and clinical research. Advanced techniques that combine in ...

Renal Ischaemia Reperfusion Injury: A Mouse Model of Injury and Regeneration

Renal ischaemia reperfusion injury (IRI) is a common cause of acute kidney injury (AKI) in patients and occlusion of renal blood flow is unavoidable during renal transplantation. Experimental models that accurately and reproducibly recapitulate renal IRI are crucial in dissecting the pathophysiology of AKI and the development of novel therapeutic agents. Presented here is a mouse model of renal IRI that results in reproducible AKI. This is achieved by a midline laparotomy approach for the surgery with one incision allowing both a right nephrectomy that provides control tissue and clamping of the left renal pedicle to induce ischaemia of the left kidney. By careful monitoring of the clamp position and body temperature during the period of ischaemia this model achieves reproducible functional and structural injury. Mice sacrificed 24 hr&#160;following surgery demonstrate loss of renal function with elevation of the serum or plasma creatinine level as well as structural kidney damage with acute tubular necrosis evident. Renal function improves and the acute tissue injury resolves during the course of 7 days following renal IRI such that this model may be used to study renal regeneration. This model of renal IRI has been utilized to study the molecular and cellular pathophysiology of AKI as well as analysis of the subsequent renal regeneration.

The mouse model of renal ischaemia reperfusion injury described here comprises of a right nephrectomy that provides control tissue and clamping of the left renal pedicle to induce ischaemia that results in acute kidney injury. This model uses a midline laparotomy approach with all steps performed via one incision.

Renal ischaemia reperfusion injury (IRI) is a common cause of acute kidney injury (AKI) in patients and occlusion of renal blood flow is unavoidable ...

A Murine Model of Irreversible and Reversible Unilateral Ureteric Obstruction

Obstruction of the kidney may affect native or transplanted kidneys and results in kidney injury and scarring. Presented here is a model of obstructive nephropathy induced by unilateral ureteric obstruction (UUO), which can either be irreversible (UUO) or reversible (R-UUO). In the irreversible UUO model, the ureter may be obstructed for variable periods of time in order to induce increasingly severe renal inflammation and interstitial fibrotic scarring. In the reversible R-UUO model the ureter is obstructed to induce hydronephrosis, tubular dilation and inflammation. After a suitable period of time the ureteric obstruction is then surgically reversed by anastomosis of the severed previously obstructed ureter to the bladder in order to allow complete decompression of the kidney and restoration of urinary flow to the bladder. The irreversible UUO model has been used to investigate various aspects of renal inflammation and scarring including the pathogenesis of disease and the testing of potential anti-inflammatory or anti-fibrotic therapies. The more challenging model of R-UUO has been used by some investigators and does offer significant research potential as it allows the study of inflammatory and immune processes and tissue remodeling in an injured and scarred kidney following the removal of the injurious stimulus. As a result, the R-UUO model offers investigators the opportunity to explore the resolution of kidney inflammation together with key aspects of tissue repair. These experimental models are of relevance to human disease as patients often present with obstruction of the renal tract that requires decompression and are commonly left with significant residual kidney impairment that has no current treatment options and may lead to eventual end stage kidney failure.

The murine model of irreversible unilateral ureteric obstruction (UUO) is presented together with the model of reversible UUO in which the ureteric obstruction is relieved by anastomosis of the severed ureter into the bladder. These models enable the study of renal inflammation and scarring as well as tissue remodeling.

Obstruction of the kidney may affect native or transplanted kidneys and results in kidney injury and scarring. Presented here is a model of obstructive ...

A Repetitive Concussive Head Injury Model in Mice

Despite the concussion/ mild traumatic brain injury (mTBI) being the most frequent occurrence of traumatic brain injury, there is still a lack of knowledge on the injury and its effects. To develop a better understanding of concussions, animals are often used because they provide a controlled, rigorous, and efficient model. Studies have adapted traditional animal models to perform mTBI to stimulate mild injury severity by changing the injury parameters. These models have been used because they can produce morphologically similar brain injuries to the clinical condition and provide a spectrum of injury severities. However, they are limited in their ability to present the identical features of injuries in patients. Using a traditional impact system, a repetitive concussive injury (rCHI) model can induce mild to moderate human-like concussion. The injury degree can be determined by measuring the period of loss of consciousness (LOC) with a sign of a transient termination of breathing. The rCHI model is beneficial to use for its accuracy and simplicity in determining mTBI effects and potential treatments.

Concussion presents the most common type of traumatic brain injury. Therefore, a repetitive concussive animal model, which replicates the important features of an injury in patients, may provide a means to study concussion in a rigorous, controlled, and efficient manner.

Despite the concussion/ mild traumatic brain injury (mTBI) being the most frequent occurrence of traumatic brain injury, there is still a lack of ...

Induction of Accelerated Atherosclerosis in Mice: The "Wire-Injury" Model

Atherosclerosis is a proliferative fibro-inflammatory disease developing in the arterial wall, inducing a deficient blood flow or a lack of blood flow. Moreover, by rupture of the defective vascular wall, atherosclerosis induces occlusive thrombus formation, which represents the main cause of myocardial infarction or stroke and the most frequent cause of death. Despite the advances in the cardiovascular field, many questions remain unanswered, and additional basic research is essential to improve our understanding of the molecular mechanisms during atherosclerosis and its effects. Due to limited clinical studies, there is a need for representative animal models recreating atherosclerotic conditions such as neointima formation after stent implantation, balloon angioplasty, or endarterectomy. Since the mouse presents many advantages and is the most frequently used model for studying molecular processes, the current study proposes an invasive procedure of endothelial denudation, also known as the wire-injury model, which is representative of the human condition of neointima formation in arteries after revascularization procedures.

This study describes an invasive procedure for the induction of accelerated atherosclerosis in mice. In comparison to other methods using electric- or cryo-induced injury, mechanical-induced injury mimics the human condition of restenosis after revascularization therapies and is ideal for the study of the molecular mechanisms involved.

Atherosclerosis is a proliferative fibro-inflammatory disease developing in the arterial wall, inducing a deficient blood flow or a lack of blood flow. ...

Bioluminescence and Near-infrared Imaging of Optic Neuritis and Brain Inflammation in the EAE Model of Multiple Sclerosis in Mice

Experimental autoimmune encephalomyelitis (EAE) in SJL/J mice is a model for relapsing-remitting multiple sclerosis (RRMS). Clinical EAE scores describing motor function deficits are basic readouts of the immune-mediated inflammation of the spinal cord. However, scores and body weight do not allow for an in vivo assessment of brain inflammation and optic neuritis. The latter is an early and frequent manifestation in about 2/3 of MS patients. Here, we show methods for bioluminescence and near-infrared live imaging to assess EAE evoked optic neuritis, brain inflammation, and blood-brain barrier (BBB) disruption in living mice using an in vivo imaging system. A bioluminescent substrate activated by oxidases primarily showed optic neuritis. The signal was specific and allowed the visualization of medication effects and disease time courses, which paralleled the clinical scores. Pegylated fluorescent nanoparticles that remained within the vasculature for extended periods of time were used to assess the BBB integrity. Near-infrared imaging revealed a BBB leak at the peak of the disease. The signal was the strongest around the eyes. A near-infrared substrate for matrix metalloproteinases was used to assess EAE-evoked inflammation. Auto-fluorescence interfered with the signal, requiring spectral unmixing for quantification. Overall, bioluminescence imaging was a reliable method to assess EAE-associated optic neuritis and medication effects and was superior to the near-infrared techniques in terms of signal specificity, robustness, ease of quantification, and cost.

We show a technique for in vivo live bioluminescence and near-infrared imaging of optic neuritis and encephalitis in the experimental autoimmune encephalomyelitis (EAE) model for multiple sclerosis in SJL/J mice.

Experimental autoimmune encephalomyelitis (EAE) in SJL/J mice is a model for relapsing-remitting multiple sclerosis (RRMS). Clinical EAE scores describing ...

Dry Powder and Nebulized Aerosol Inhalation of Pharmaceuticals Delivered to Mice Using a Nose-only Exposure System

Obstructive respiratory diseases like asthma and chronic obstructive pulmonary disease (COPD) are currently treated by inhaled anti-inflammatory and bronchodilator drugs. Despite the availability of multiple treatments, both diseases are growing public health concerns. The majority of asthma patients are well controlled on current inhaled therapies but a substantial number of patients with severe asthma are not. Asthma affects an estimated 300 million people worldwide and approximately 20 percent have a severe form of the disease. In contrast to asthma, there are few effective therapies for COPD. An estimated 10% of the population has COPD and the trend in death rates is increasing for COPD while decreasing for other major diseases. Although developing drugs for inhaled delivery is challenging, the nose-only inhalation unit enables direct delivery of novel drugs to the lung of rodents for pre-clinical efficacy and safety/toxicology studies. Inhaled drug delivery has multiple advantages for respiratory diseases, where high concentration in the lung improves efficacy and minimizes systemic side effects. Inhaled corticosteroids and bronchodilators benefit from these advantages and inhaled delivery may also hold potential for future biologic therapies. The inhalation unit described herein can generate, sample for characterization, and uniformly deposit a drug aerosol in the lungs of rodents. This enables the pre-clinical determination of the efficacy and safety of drug doses deposited in the lungs of rodents, key data required before initiating clinical development.

The inhalation unit described herein can generate, sample for characterization, and uniformly deposit a drug aerosol in the lungs of rodents. This enables the pre-clinical determination of the efficacy and safety of drug doses deposited in the lungs; key data enabling clinical inhaled drug development.

Obstructive respiratory diseases like asthma and chronic obstructive pulmonary disease (COPD) are currently treated by inhaled anti-inflammatory and ...

Murine Oropharyngeal Aspiration Model of Ventilator-associated and Hospital-acquired Bacterial Pneumonia

Murine infection models are critical for understanding disease pathogenesis and testing the efficacy of novel therapeutics designed to combat causative pathogens. Infectious pneumonia is among the most common infections presented by patients in the clinic and thus warrants an appropriate in vivo model. Typical pneumonia models use intranasal inoculation, which deposits excessive organisms outside the lung, causing off-target complications and symptoms, such as sinusitis, gastritis, enteritis, physical trauma, or microparticle misting to mimic aerosol spread more typical of viral, tuberculous, or fungal pneumonia. These models do not accurately reflect the pathogenesis of typical community- or healthcare-acquired bacterial pneumonia. In contrast, this murine model of oropharyngeal aspiration pneumonia mimics the droplet route in healthcare-acquired pneumonia. Inoculating 50 &#181;L of the bacteria suspension into the oropharynx of anesthetized mice causes reflexive aspiration, which results in pneumonia. With this model, one can examine the pathogenesis of pneumonia-causing pathogens and new treatments to combat these diseases.

Infectious pneumonia is among the most common infections in human. An appropriate in vivo model is critical for understanding disease pathogenesis and testing the efficacy of novel therapeutics. With this murine oropharyngeal aspiration pneumonia model, one can examine the pathogenesis and new treatments against these deadly infections.

Murine infection models are critical for understanding disease pathogenesis and testing the efficacy of novel therapeutics designed to combat causative ...