This work was supported by National Institutes of Allergy and Infectious Diseases Grant P01 A1078894 to C.A.G.

<ol>
	<li>Nathan, C., Ding, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nonresolving+Inflammation.">Nonresolving Inflammation.</a> Cell. 140 (6), 871-882 (2010).</li><li>Karin, M., Lawrence, T., Nizet, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Innate+immunity+gone+awry:+linking+microbial+infections+to+chronic+inflammation+and.">Innate immunity gone awry: linking microbial infections to chronic inflammation and.</a> 124, 823-835 (2006).</li><li>Connor, S. M., Taylor, C. E., Hughes, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Emerging+infectious+determinants+of+chronic+diseases.">Emerging infectious determinants of chronic diseases.</a> Emerging Infectious Diseases. 12 (7), 1051-1057 (2006).</li><li>Barth, K., Remick, D. G., Genco, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Disruption+of+immune+regulation+by+microbial+pathogens+and+resulting+chronic+inflammation.">Disruption of immune regulation by microbial pathogens and resulting chronic inflammation.</a> Journal of Cellular Physiology. , (2012).</li><li>Hayashi, C., Gudino, C. V., Gibson, F. C., Genco, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Review:+Pathogen-induced+inflammation+at+sites+distant+from+oral+infection:+bacterial+persistence+and+induction+of+cell-specific+innate+immune+inflammatory+pathways.">Review: Pathogen-induced inflammation at sites distant from oral infection: bacterial persistence and induction of cell-specific innate immune inflammatory pathways.</a> Molecular Oral Microbiology. 25 (5), 305-316 (2010).</li><li>Gibson, F. C., Ukai, T., Genco, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engagement+of+specific+innate+immune+signaling+pathways+during+Porphyromonas+gingivalis+induced+chronic+inflammation+and+atherosclerosis.">Engagement of specific innate immune signaling pathways during Porphyromonas gingivalis induced chronic inflammation and atherosclerosis.</a> Frontiers in Bioscience: a Journal and Virtual Library. 13, 2041-2059 (2008).</li><li>Pihlstrom, B. L., Michalowicz, B. S., Johnson, N. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Periodontal+diseases.">Periodontal diseases.</a> Lancet. 366 (9499), 1809-1820 (2005).</li><li>Baker, P. J., Evans, R. T., Roopenian, D. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Oral+infection+with+Porphyromonas+gingivalis+and+induced+alveolar+bone+loss+in+immunocompetent+and+severe+combined+immunodeficient+mice.">Oral infection with Porphyromonas gingivalis and induced alveolar bone loss in immunocompetent and severe combined immunodeficient mice.</a> Archives of Oral Biology. 39 (12), 1035-1040 (1994).</li><li>Baker, P. J., Carter, S., Dixon, M., Evans, R. T., Roopenian, D. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Serum+antibody+response+to+oral+infection+precedes+but+does+not+prevent+Porphyromonas+gingivalis-induced+alveolar+bone+loss+in+mice.">Serum antibody response to oral infection precedes but does not prevent Porphyromonas gingivalis-induced alveolar bone loss in mice.</a> Oral Microbiology and Immunology. 14 (3), 194-196 (1999).</li><li>Gibson, F. C., Hong, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Innate+immune+recognition+of+invasive+bacteria+accelerates+atherosclerosis+in+apolipoprotein+E-deficient+mice.">Innate immune recognition of invasive bacteria accelerates atherosclerosis in apolipoprotein E-deficient mice.</a> Circulation. 109 (22), 2801-2806 (2004).</li><li>Hayashi, C., Viereck, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Porphyromonas+gingivalis+accelerates+inflammatory+atherosclerosis+in+the+innominate+artery+of+ApoE+deficient+mice.">Porphyromonas gingivalis accelerates inflammatory atherosclerosis in the innominate artery of ApoE deficient mice.</a> Atherosclerosis. 215 (1), 52-59 (2011).</li><li>Hayashi, C., Madrigal, A. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathogen-mediated+inflammatory+atherosclerosis+is+mediated+in+part+via+Toll-like+receptor+2-induced+inflammatory+responses.">Pathogen-mediated inflammatory atherosclerosis is mediated in part via Toll-like receptor 2-induced inflammatory responses.</a> Journal of Innate Immunity. 2 (4), 334-343 (2010).</li><li>Hayashi, C., Papadopoulos, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Protective+role+for+TLR4+signaling+in+atherosclerosis+progression+as+revealed+by+infection+with+a+common+oral+pathogen.">Protective role for TLR4 signaling in atherosclerosis progression as revealed by infection with a common oral pathogen.</a> Journal of Immunology (Baltimore, Md.: 1950). 189 (7), 3681-3688 (2012).</li><li>Papadopoulos, G., Weinberg, E. O., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macrophage-Specific+TLR2+Signaling+Mediates+Pathogen-Induced+TNF-Dependent+Inflammatory+Oral+Bone+Loss.">Macrophage-Specific TLR2 Signaling Mediates Pathogen-Induced TNF-Dependent Inflammatory Oral Bone Loss.</a> The Journal of Immunology. , (2012).</li><li>Gibson, F. C., Hong , C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Innate+immune+recognition+of+invasive+bacteria+accelerates+atherosclerosis+in+apolipoprotein+E-deficient+mice.">Innate immune recognition of invasive bacteria accelerates atherosclerosis in apolipoprotein E-deficient mice.</a> Circulation. 109 (22), 2801-2806 (2004).</li><li>Miyamoto, T., Yumoto, H., Takahashi, Y., Davey, M., Gibson, F. C., Genco, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathogen-accelerated+atherosclerosis+occurs+early+after+exposure+and+can+be+prevented+via+immunization.">Pathogen-accelerated atherosclerosis occurs early after exposure and can be prevented via immunization.</a> Infection and Immunity. 74 (2), 1376-1380 (2006).</li><li>Baker, P. J., Dixon, M., Roopenian, D. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+control+of+susceptibility+to+Porphyromonas+gingivalis-induced+alveolar+bone+loss+in+mice.">Genetic control of susceptibility to Porphyromonas gingivalis-induced alveolar bone loss in mice.</a> Infection and Immunity. 68 (10), 5864-5868 (2000).</li><li>Baker, P. J., Dixon, M., Evans, R. T., Roopenian, D. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Heterogeneity+of+Porphyromonas+gingivalis+strains+in+the+induction+of+alveolar+bone+loss+in+mice.">Heterogeneity of Porphyromonas gingivalis strains in the induction of alveolar bone loss in mice.</a> Oral Microbiology and Immunology. 15 (1), 27-32 (2000).</li><li>Daugherty, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mouse+models+of+atherosclerosis.">Mouse models of atherosclerosis.</a> The American Journal of the Medical Sciences. 323 (1), 3-10 (2002).</li><li>Weinreb, D. B., Aguinaldo, J. G. S., Feig, J. E., Fisher, E. A., Fayad, Z. 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The authors declare that they have no competing financial interests.

The P. gingivalis oral infection model provides a valuable tool for the study of pathogen-induced chronic inflammation at local and systemic sites. This unique model permits the characterization of both host and pathogen specific mechanisms contributing to chronic inflammation and immunopathology. In addition, the model can be used to screen for novel therapeutic strategies, including immunization and pharmacological intervention. The steps outlined in this protocol describe the successful use of this model and ...

Chronic inflammation is a major driver of pathological tissue damage and a unifying characteristic of many chronic diseases in humans. These diseases include neoplastic, autoimmune, and chronic inflammatory diseases1. The etiology of many chronic diseases remains unclear but is understood to be complex and multifactorial, involving both genetic predisposition and the introduction of environmental factors. While the perpetuators of inflammation remain elusive, the cellular and molecular profiles of immune activation overlap considerably with those patterns observed in host responses to pathogens2. 
Mounting evidence implicates infection with microbial pathogens in the development and progression of chronic inflammation and its diverse clinical manifestations2,3. Pathogens can induce and sustain chronic inflammation directly by subverting the host immune system and establishing persistent infections4. In the absence of microbial persistence, infection can precipitate chronic inflammation from autoimmune reactions triggered by molecular mimicry to self-antigens, changes in self-antigens that render them immunogenic, or damage that releases previously masked host antigens. Rarely however have specific pathogens been identified as the universal cause of a particular chronic disease. Rather, the majority of available data suggests that pathogens use distinct mechanisms to elicit chronic inflammation with a wide spectrum of clinical manifestations and disease outcomes in the genetically susceptible host3. Thus, a detailed understanding of the mechanisms by which specific pathogens induce chronic inflammation may have major implications for public health, as well as treatment and prevention of many chronic diseases. 
Although the host and pathogen specific mechanisms contributing to the induction and maintenance of chronic inflammation are poorly understood, advances in modeling of pathogen-induced chronic inflammation have begun to further our understanding of these processes. The P. gingivalis oral infection model is a unique, well-characterized mouse model of pathogen-induced chronic inflammation that permits the analysis of host and pathogen specific mechanisms contributing to chronic inflammation at local (oral bone loss) and systemic sites (atherosclerosis)5,6. 
P. gingivalis is a Gram-negative, anaerobic oral pathogen implicated in human periodontal disease, an infection-driven chronic inflammatory disease characterized by the destruction of tooth supporting tissue7. In addition to pathology at the initial site of infection, accumulating evidence implicates P. gingivalis-induced chronic inflammation in the development and progression of systemic diseases including atherosclerosis5, a disease characterized by chronic inflammation of the arterial vessel wall. Oral infection of specific-pathogen free mice with P. gingivalis induces a local inflammatory response that results in destruction of tooth supporting alveolar bone8. P. gingivalis can be recovered from the mouths of infected mice up to 42 days post-infection8 and mice develop high levels of pathogen-specific serum antibody titers9. In an established mouse model of atherosclerosis using Apolipoprotein-E-/- mice (ApoE-/-), oral infection with P. gingivalis induces chronic inflammation that drives inflammatory plaque deposition within the aortic sinus10 and the innominate artery11. Progressive inflammation within the innominate artery of P. gingivalis-infected mice can be monitored in live animals using in vivo MRI. Histologically, arterial lesions from P. gingivalis-infected mice exhibit increased accumulation of lipids accompanied by activation of the vascular endothelium, an increased immune cell infiltrate, and elevated expression of inflammatory mediators12. Use of this model in knockout mice has elucidated the role of host signaling components and inflammatory mediators, as well as the cell specific interactions that drive P. gingivalis-induced immunopathology12&#8211;14. In addition, experiments utilizing defined bacterial mutants have identified critical P. gingivalis virulence factors contributing to chronic inflammation at local and systemic sites15. 
This article details methodologies for the assessment of P. gingivalis-induced chronic inflammation at local and systemic sites. We provide a detailed protocol for the analysis of alveolar bone loss by microCT using Amira software. In addition, we define the utility of serial in vivo live animal MRI for the assessment of progressive inflammation within the innominate artery. We include methodologies for the visualization and quantification of inflammatory plaque in arterial lesions, and describe their histological characterization. The use of transgenic mice and defined bacterial mutants makes this model particularly suitable for identifying both host and microbial factors involved in the initiation, progression, and outcome of disease. Additionally, the model can be used to screen for novel therapeutic strategies, including vaccination and pharmacological intervention.

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			<td style="width:196px;">Company</td>
			<td style="width:132px;">Catalogue Number</td>
			<td style="width:88px;">Comments&#160;</td>
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			<td>Visualization Sciences Group</td>
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			<td height="21" style="height:21px;">Anaerobic chamber DW Scientific Model MG500&#160;</td>
			<td>Microbiology International</td>
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			<td height="21" style="height:21px;">BHI&#160;</td>
			<td>Becton-Dickinson&#160;</td>
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			<td>Sigma-Aldrich&#160;</td>
			<td>51280-5G</td>
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			<td height="21" style="height:21px;">Menadione (Vitamin K)</td>
			<td>Sigma-Aldrich&#160;&#160;</td>
			<td>M5625-25G</td>
			<td></td>
		</tr>
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			<td height="21" style="height:21px;">Yeast Extract</td>
			<td>Becton-Dickinson&#160;</td>
			<td>212750</td>
			<td></td>
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			<td height="21" style="height:21px;">Carboxymethyl cellulose (medium viscocity)&#160;</td>
			<td>Sigma-Aldrich&#160;</td>
			<td>C-4888</td>
			<td></td>
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			<td height="21" style="height:21px;">Sulfamethoxazole and Trimethoprim Oral Suspension 200 mg/40 mg per 5ml</td>
			<td>Hi-Tech Pharmacal</td>
			<td>NDC 50383-823-16</td>
			<td></td>
		</tr>
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			<td height="21" style="height:21px;">&#956;CT 40&#160;</td>
			<td>Scanco</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">HistoChoice Tissue Fixative</td>
			<td>Sigma-Aldrich&#160;</td>
			<td>H2904</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;">Sudan IV</td>
			<td>Sigma-Aldrich&#160;</td>
			<td>S4261-25G</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;">vertical-bore 11.7T Avance spectrometer&#160;</td>
			<td>Bruker</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Paravision</td>
			<td>Paravision</td>
			<td></td>
			<td></td>
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			<td height="21" style="height:21px;">ImageJ</td>
			<td>NIH</td>
			<td></td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;">rat anti-mouse F4/80</td>
			<td>Serotec</td>
			<td>MCA497R</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">rat anti-mouse TLR2</td>
			<td>eBioscience</td>
			<td>13-9021-80</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Leica S4 Dissecting Scope</td>
			<td>Leica</td>
			<td></td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;">Microm HM 550 Cryostat</td>
			<td>Microm</td>
			<td></td>
			<td></td>
		</tr>
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a mouse model for pathogen-induced chronic inflammation at local and systemic sites

Chronic inflammation is a major driver of pathological tissue damage and a unifying characteristic of many chronic diseases in humans including neoplastic, autoimmune, and chronic inflammatory diseases. Emerging evidence implicates pathogen-induced chronic inflammation in the development and progression of chronic diseases with a wide variety of clinical manifestations. Due to the complex and multifactorial etiology of chronic disease, designing experiments for proof of causality and the establishment of mechanistic links is nearly impossible in humans. An advantage of using animal models is that both genetic and environmental factors that may influence the course of a particular disease can be controlled. Thus, designing relevant animal models of infection represents a key step in identifying host and pathogen specific mechanisms that contribute to chronic inflammation.
Here we describe a mouse model of pathogen-induced chronic inflammation at local and systemic sites following infection with the oral pathogen Porphyromonas gingivalis, a bacterium closely associated with human periodontal disease. Oral infection of specific-pathogen free mice induces a local inflammatory response resulting in destruction of tooth supporting alveolar bone, a hallmark of periodontal disease. In an established mouse model of atherosclerosis, infection with P. gingivalis accelerates inflammatory plaque deposition within the aortic sinus and innominate artery, accompanied by activation of the vascular endothelium, an increased immune cell infiltrate, and elevated expression of inflammatory mediators within lesions. We detail methodologies for the assessment of inflammation at local and systemic sites. The use of transgenic mice and defined bacterial mutants makes this model particularly suitable for identifying both host and microbial factors involved in the initiation, progression, and outcome of disease. Additionally, the model can be used to screen for novel therapeutic strategies, including vaccination and pharmacological intervention.

Using the appropriate mouse model and oral infection regimen, P. gingivalis induces chronic inflammation and immunopathology at local (oral cavity) and systemic sites (arteries) (Figure 1).
In mice, oral infection with P. gingivalis induces a local inflammatory response that drives the destruction of tooth supporting alveolar bone8. P. gingivalis-infected mice develop serum antibody responses to this organism that are predominantly of the ...

Watch this Scientific Journal Video about A Mouse Model for Pathogen-induced Chronic Inflammation at Local and Systemic Sites at JoVE.com

A Mouse Model for Pathogen-induced Chronic Inflammation at Local and Systemic Sites

Animal models have proven to be invaluable tools in defining host and pathogen specific mechanisms that contribute to the development of chronic inflammation. Here we describe a mouse model of oral infection with the human pathogen Porphyromonas gingivalis and detail methodologies to assess the progression of inflammation at local and systemic sites.

Chronic inflammation is a major driver of pathological tissue damage and a unifying characteristic of many chronic diseases in humans including ...

a-mouse-model-for-pathogen-induced-chronic-inflammation-at-local

Research

JoVE Journal

Immunology and Infection

17.5K Views.  Boston University School of Medicine. Animal models have proven to be invaluable tools in defining host and pathogen specific mechanisms that contribute to the development of chronic inflammation. Here we describe a mouse model of oral infection with the human pathogen Porphyromonas gingivalis and detail methodologies to assess the progression of inflammation at local and systemic sites.

Video: A Mouse Model for Pathogen-induced Chronic Inflammation at Local and Systemic Sites

Using the BLT Humanized Mouse as a Stem Cell based Gene Therapy Tumor Model

Small animal models such as mice have been extensively used to study human disease and to develop new therapeutic interventions. Despite the wealth of information gained from these studies, the unique characteristics of mouse immunity as well as the species specificity of viral diseases such as human immunodeficiency virus (HIV) infection led to the development of humanized mouse models. The earlier models involved the use of C. B 17 scid/scid mice and the transplantation of human fetal thymus and fetal liver termed thy/liv (SCID-hu) 1, 2 or the adoptive transfer of human peripheral blood leukocytes (SCID-huPBL) 3. Both models were mainly utilized for the study of HIV infection.
One of the main limitations of both of these models was the lack of stable reconstitution of human immune cells in the periphery to make them a more physiologically relevant model to study HIV disease. To this end, the BLT humanized mouse model was developed. BLT stands for bone marrow/liver/thymus. In this model, 6 to 8 week old NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ (NSG) immunocompromised mice receive the thy/liv implant as in the SCID-hu mouse model only to be followed by a second human hematopoietic stem cell transplant 4. The advantage of this system is the full reconstitution of the human immune system in the periphery. This model has been used to study HIV infection and latency 5-8.
We have generated a modified version of this model in which we use genetically modified human hematopoietic stem cells (hHSC) to construct the thy/liv implant followed by injection of transduced autologous hHSC 7, 9. This approach results in the generation of genetically modified lineages. More importantly, we adapted this system to examine the potential of generating functional cytotoxic T cells (CTL) expressing a melanoma specific T cell receptor. Using this model we were able to assess the functionality of our transgenic CTL utilizing live positron emission tomography (PET) imaging to determine tumor regression (9).
The goal of this protocol is to describe the process of generating these transgenic mice and assessing in vivo efficacy using live PET imaging. As a note, since we use human tissues and lentiviral vectors, our facilities conform to CDC NIH guidelines for Biosafety Level 2 (BSL2) with special precautions (BSL2+). In addition, the NSG mice are severely immunocompromised thus, their housing and maintenance must conform to the highest health standards (<a href="http://jaxmice.jax.org/research/immunology/005557-housing.html" target="_blank">http://jaxmice.jax.org/research/immunology/005557-housing.html</a>).

The generation and characterization of tumor specific T cells using humanized mice is described here. Human thymic tissue and genetically modified human hematopoietic stem cells are transplanted into immunocompromised mice. This results in the reconstitution of an engineered human immune system allowing for in vivo examination of anti-tumor immune responses.

Small animal models such as mice have been extensively used to study human  disease and to develop new therapeutic interventions. Despite the wealth of  ...

In vivo Imaging Method to Distinguish Acute and Chronic Inflammation

Inflammation is a fundamental aspect of many human diseases. In this video report, we demonstrate non-invasive bioluminescence imaging techniques that distinguish acute and chronic inflammation in mouse models. With tissue damage or pathogen invasion, neutrophils are the first line of defense, playing a major role in mediating the acute inflammatory response. As the inflammatory reaction progresses, circulating monocytes gradually migrate into the site of injury and differentiate into mature macrophages, which mediate chronic inflammation and promote tissue repair by removing tissue debris and producing anti-inflammatory cytokines. Intraperitoneal injection of luminol (5-amino-2,3-dihydro-1,4-phthalazinedione, sodium salt) enables detection of acute inflammation largely mediated by tissue-infiltrating neutrophils. Luminol specifically reacts with the superoxide generated within the phagosomes of neutrophils since bioluminescence results from a myeloperoxidase (MPO) mediated reaction. Lucigenin (bis-N-methylacridinium nitrate) also reacts with superoxide in order to generate bioluminescence. However, lucigenin bioluminescence is independent of MPO and it solely relies on phagocyte NADPH oxidase (Phox) in macrophages during chronic inflammation. Together, luminol and lucigenin allow non-invasive visualization and longitudinal assessment of different phagocyte populations across both acute and chronic inflammatory phases. Given the important role of inflammation in a variety of human diseases, we believe this non-invasive imaging method can help investigate the differential roles of neutrophils and macrophages in a variety of pathological conditions.

In vivo Imaging Method to Distinguish Acute and Chronic Inflammation

We describe a non-invasive imaging method for distinguishing inflammatory stages. Systemic delivery of luminol reveals areas of acute inflammation dependent upon MPO activity in neutrophils. In contrast, injection of lucigenin allows for visualization of chronic inflammation dependent upon Phox activity in macrophages.

Inflammation is a fundamental aspect of many human diseases. In this video report, we demonstrate non-invasive bioluminescence imaging techniques that ...

In vitro Coculture Assay to Assess Pathogen Induced Neutrophil Trans-epithelial Migration

Mucosal surfaces serve as protective barriers against pathogenic organisms.&#160;Innate immune responses are activated upon sensing pathogen leading to the infiltration of tissues with migrating inflammatory cells, primarily neutrophils.&#160;This process has the potential to be destructive to tissues if excessive or held in an unresolved state.&#160; Cocultured in vitro models can be utilized to study the unique molecular mechanisms involved in pathogen induced neutrophil trans-epithelial migration.&#160;This type of model provides versatility in experimental design with opportunity for controlled manipulation of the pathogen, epithelial barrier, or neutrophil.&#160;Pathogenic infection of the apical surface of polarized epithelial monolayers grown on permeable transwell filters instigates physiologically relevant basolateral to apical trans-epithelial migration of neutrophils applied to the basolateral surface.&#160;The in vitro model described herein demonstrates the multiple steps necessary for demonstrating neutrophil migration across a polarized lung epithelial monolayer that has been infected with pathogenic P. aeruginosa (PAO1).&#160;Seeding and culturing of permeable transwells with human derived lung epithelial cells is described, along with isolation of neutrophils from whole human blood and culturing of PAO1 and nonpathogenic K12 E. coli (MC1000).&#160; The emigrational process and quantitative analysis of successfully migrated neutrophils that have been mobilized in response to pathogenic infection is shown with representative data, including positive and negative controls.&#160;This in vitro model system can be manipulated and applied to other mucosal surfaces.&#160;Inflammatory responses that involve excessive neutrophil infiltration can be destructive to host tissues and can occur in the absence of pathogenic infections.&#160;A better understanding of the molecular mechanisms that promote neutrophil trans-epithelial migration through experimental manipulation of the in vitro coculture assay system described herein has significant potential to identify novel therapeutic targets for a range of mucosal infectious as well as inflammatory diseases.

In vitro Coculture Assay to Assess Pathogen Induced Neutrophil Trans-epithelial Migration

Neutrophil trans-epithelial migration in response to mucosal bacterial infection contributes to epithelial injury and clinical disease.&#160;An in vitro model has been developed that combines pathogen, human neutrophils, and polarized human epithelial cell layers grown on transwell filters to facilitate investigations towards unraveling the molecular mechanisms orchestrating this phenomenon.

Mucosal surfaces serve as protective barriers against pathogenic organisms.&#160;Innate immune responses are activated upon sensing pathogen leading to ...

Systemic Injection of Neural Stem/Progenitor Cells in Mice with Chronic EAE

Neural stem/precursor cells (NPCs) are a promising stem cell source for transplantation approaches aiming at brain repair or restoration in regenerative neurology. This directive has arisen from the extensive evidence that brain repair is achieved after focal or systemic NPC transplantation in several preclinical models of neurological diseases.
These experimental data have identified the cell delivery route as one of the main hurdles of restorative stem cell therapies for brain diseases that requires urgent assessment. Intraparenchymal stem cell grafting represents a logical approach to those pathologies characterized by isolated and accessible brain lesions such as spinal cord injuries and Parkinson's disease. Unfortunately, this principle is poorly applicable to conditions characterized by a multifocal, inflammatory and disseminated (both in time and space) nature, including multiple sclerosis (MS). As such, brain targeting by systemic NPC delivery has become a low invasive and therapeutically efficacious protocol to deliver cells to the brain and spinal cord of rodents and nonhuman primates affected by experimental chronic inflammatory damage of the central nervous system (CNS).
This alternative method of cell delivery relies on the NPC pathotropism, specifically their innate capacity to (i) sense the environment via functional cell adhesion molecules and inflammatory cytokine and chemokine receptors; (ii) cross the leaking anatomical barriers after intravenous (i.v.) or intracerebroventricular (i.c.v.) injection; (iii) accumulate at the level of multiple perivascular site(s) of inflammatory brain and spinal cord damage; and (i.v.) exert remarkable tissue trophic and immune regulatory effects onto different host target cells in vivo.
Here we describe the methods that we have developed for the i.v. and i.c.v. delivery of syngeneic NPCs in mice with experimental autoimmune encephalomyelitis (EAE), as model of chronic CNS inflammatory demyelination, and envisage the systemic stem cell delivery as a valuable technique for the selective targeting of the inflamed brain in regenerative neurology.

The transplantation of neural stem/progenitor cells (NPCs) holds great promises in regenerative neurology. The systemic delivery of NPCs has turned into effective, low invasive, and therapeutically very efficacious protocol to deliver stem cells in the brain and spinal cord of rodents and nonhuman primates affected by experimental chronic inflammatory damage of the central nervous system.

Neural stem/precursor cells (NPCs) are a promising stem cell source for transplantation approaches aiming at brain repair or restoration in regenerative ...

Induction of Murine Intestinal Inflammation by Adoptive Transfer of Effector CD4+CD45RBhigh T Cells into Immunodeficient Mice

There are many different animal models available for studying the pathogenesis of human inflammatory bowel diseases (IBD), each with its own advantages and disadvantages. We describe here an experimental colitis model that is initiated by adoptive transfer of syngeneic splenic CD4+CD45RBhigh T cells into T and B cell deficient recipient mice. The CD4+CD45RBhigh T cell population that largely consists of na&#239;ve effector cells is capable of inducing chronic intestinal inflammation, closely resembling key aspects of human IBD. This method can be manipulated to study aspects of disease onset and progression. Additionally it can be used to study the function of innate, adaptive, and regulatory immune cell populations, and the role of environmental exposures, i.e., the microbiota, in intestinal inflammation. In this article we illustrate the methodology for inducing colitis with a step-by-step protocol. This includes a video demonstration of key technical aspects required to successfully develop this murine model of experimental colitis for research purposes.

Induction of Murine Intestinal Inflammation by Adoptive Transfer of Effector CD4+CD45RBhigh T Cells into Immunodeficient Mice

Here, we present a protocol to induce colonic inflammation in mice by adoptive transfer of syngeneic CD4+CD45RBhigh T cells into T and B cell deficient recipients. Clinical and histopathological features mimic human inflammatory bowel diseases. This method allows the study of the initiation of colonic inflammation and progression of disease.

There are many different animal models available for studying the pathogenesis of human inflammatory bowel diseases (IBD), each with its own advantages ...

Co-immunoprecipitation of the Mouse Mx1 Protein with the Influenza A Virus Nucleoprotein

Studying the interaction between proteins is key in understanding their function(s). A very powerful method that is frequently used to study interactions of proteins with other macromolecules in a complex sample is called co-immunoprecipitation. The described co-immunoprecipitation protocol allows to demonstrate and further investigate the interaction between the antiviral myxovirus resistance protein 1 (Mx1) and one of its viral targets, the influenza A virus nucleoprotein (NP). The protocol starts with transfected mammalian cells, but it is also possible to use influenza A virus infected cells as starting material. After cell lysis, the viral NP protein is pulled-down with a specific antibody and the resulting immune-complexes are precipitated with protein G beads. The successful pull-down of NP and the co-immunoprecipitation of the antiviral Mx1 protein are subsequently revealed by western blotting. A prerequisite for successful co-immunoprecipitation of Mx1 with NP is the presence of N-ethylmaleimide (NEM) in the cell lysis buffer. NEM alkylates free thiol groups. Presumably this reaction stabilizes the weak and/or transient NP&#8211;Mx1 interaction by preserving a specific conformation of Mx1, its viral target or an unknown third component. An important limitation of co-immunoprecipitation experiments is the inadvertent pull-down of contaminating proteins, caused by nonspecific binding of proteins to the protein G beads or antibodies. Therefore, it is very important to include control settings to exclude false positive results. The described co-immunoprecipitation protocol can be used to study the interaction of Mx proteins from different vertebrate species with viral proteins, any pair of proteins, or of a protein with other macromolecules. The beneficial role of NEM to stabilize weak and/or transient interactions needs to be tested for each interaction pair individually.

This co-immunoprecipitation protocol allows to study the interaction between the influenza A virus nucleoprotein and the antiviral Mx1 protein in human cells. The protocol emphasizes the importance of N-ethylmaleimide for successful co-immunoprecipitation of Mx1 and influenza A virus nucleoprotein.

Studying the interaction between proteins is key in understanding their function(s). A very powerful method that is frequently used to study interactions ...

An Optimized Method for Isolating and Expanding Invariant Natural Killer T Cells from Mouse Spleen

The ability to rapidly secrete cytokines upon stimulation is a functional characteristic of the invariant natural killer T (iNKT) cell lineage. iNKT cells are therefore characterized as an innate T cell population capable of activating and steering adaptive immune responses. The development of improved techniques for the culture and expansion of murine iNKT cells facilitates the study of iNKT cell biology in in vitro and in vivo model systems. Here we describe an optimized procedure for the isolation and expansion of murine splenic iNKT cells.
Spleens from C57Bl/6 mice are removed, dissected and strained and the resulting cellular suspension is layered over density gradient media. Following centrifugation, splenic mononuclear cells (MNCs) are collected and CD5-positive (CD5+) lymphocytes are enriched for using magnetic beads. iNKT cells within the CD5+ fraction are subsequently stained with &#945;GalCer-loaded CD1d tetramer and purified by fluorescence activated cell sorting (FACS). FACS sorted iNKT cells are then initially cultured in vitro using a combination of recombinant murine cytokines and plate-bound T cell receptor (TCR) stimuli before being expanded in the presence of murine recombinant IL-7. Using this technique, approximately 108 iNKT cells can be generated within 18-20 days of culture, after which they can be used for functional assays in vitro, or for in vivo transfer experiments in mice.

Here we present an adapted protocol that can be used to generate a large number of murine invariant natural killer T cells from mouse spleen. The protocol outlines an approach by which splenic iNKT cells can be enriched for, isolated and expanded in vitro using a limited number of animals and reagents.

The ability to rapidly secrete cytokines upon stimulation is a functional characteristic of the invariant natural killer T (iNKT) cell lineage. iNKT cells ...

Intra-tracheal Administration of Haemophilus influenzae in Mouse Models to Study Airway Inflammation

Here, we describe a detailed procedure to efficiently and directly deliver Haemophilus influenzae into the lower respiratory tracts of mice. We demonstrate the procedure for preparing H. influenzae inoculum, intra-tracheal instillation of H. influenzae into the lung, collection of broncho-alveolar lavage fluid (BALF), analysis of immune cells in the BALF, and RNA isolation for differential gene expression analysis. This procedure can be used to study the lung inflammatory response to any bacteria, virus or fungi. Direct tracheal instillation is mostly preferred over intranasal or aerosol inhalation procedures because it more efficiently delivers the bacterial inoculum into the lower respiratory tract with less ambiguity.

Intra-tracheal Administration of Haemophilus influenzae in Mouse Models to Study Airway Inflammation

We demonstrate the procedure for intra-tracheal inoculation of Haemophilus influenzae into the lower respiratory tracts of mice. This is a very useful tool to study signaling pathways that regulate airway inflammation in mouse models.

Here, we describe a detailed procedure to efficiently and directly deliver Haemophilus influenzae into the lower respiratory tracts of mice. We ...

Mouse Body Temperature Measurement Using Infrared Thermometer During Passive Systemic Anaphylaxis and Food Allergy Evaluation

Mouse body temperature measurement is of paramount importance for investigating allergies and anaphylactic symptoms. Rectal probes for temperature readings is common, and they have been proven to be accurate and invaluable in this regard. However, this method of temperature measurement requires the mice to be anesthetized in order to insert the probe without injury to the animal. This limits the ability to observe other phenotypes of the mouse simultaneously. In order to investigate other phenotypes while measuring temperatures, rectal probes are not ideal, and another method is desired. Here, we introduce a noninvasive method of temperature measurement that foregoes the requirement for mouse anesthesia while maintaining equal reliability to rectal probes in measuring body temperature. We use an infrared thermometer that detects body surface temperatures at ranges between 2 and 150 mm. This method of body temperature measurement is successful in reliably replicating temperature change trends during passive system anaphylaxis experiments in mice. We show that body surface temperatures are about 2.0 &#176;C lower than rectal probe measurements, but the degree of temperature drop follows the same trend. Furthermore, we use the same technique to observe mice in a food allergy model to evaluate temperature and activity levels simultaneously.

Here we present a new method to accurately measure body temperature differences in passive systemic anaphylaxis (PSA) and food allergy mouse models using an infrared thermometer. This procedure has been accurately duplicated in previous PSA results.

Mouse body temperature measurement is of paramount importance for investigating allergies and anaphylactic symptoms. Rectal probes for temperature ...

A Controlled Mouse Model for Neonatal Polymicrobial Sepsis

Neonatal sepsis remains a global burden. A preclinical model to screen effective prophylactic or therapeutic interventions is needed. Neonatal mouse polymicrobial sepsis can be induced by injecting cecal slurry intraperitoneally into day of life 7 mice and monitoring them for the following week. Presented here are the detailed steps necessary for the implementation of this neonatal sepsis model. This includes making a homogeneous cecal slurry stock, diluting it to a weight- and litter-adjusted dose, an outline of the monitoring schedule, and a definition of observed health categories used to define humane endpoints. The generation of a homogeneous cecal slurry stock from pooled donors allows for the administration into many litters over time, reducing the variation between donors, and preventing the use of potentially toxic glycerol. The monitoring strategy used allows for the anticipation of survival outcome and the identification of mice that would later progress to death, allowing for an earlier identification of the humane endpoint. Two main behavioral features are used to define the health scores, namely, the ability of the neonatal mice to right themselves when placed on their back and their level of mobility. These criteria could potentially be applied to address humane endpoints in other studies of neonatal disease in mice, as long as a pilot study is performed to confirm accuracy. In conclusion, this approach provides a standardized method to model newborn sepsis in mice, while providing resources to assess animal welfare used to define early humane endpoints for challenged animals.

This protocol provides the necessary steps to establish and evaluate neonatal sepsis in 7-day-old mice.

Neonatal sepsis remains a global burden. A preclinical model to screen effective prophylactic or therapeutic interventions is needed. Neonatal mouse ...

A Mouse Model for Pathogen-induced Chronic Inflammation at Local and Systemic Sites

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Chapters in this video

Using the BLT Humanized Mouse as a Stem Cell based Gene Therapy Tumor Model

In vivo Imaging Method to Distinguish Acute and Chronic Inflammation

In vitro Coculture Assay to Assess Pathogen Induced Neutrophil Trans-epithelial Migration

Systemic Injection of Neural Stem/Progenitor Cells in Mice with Chronic EAE

Induction of Murine Intestinal Inflammation by Adoptive Transfer of Effector CD4⁺CD45RB^high T Cells into Immunodeficient Mice

Co-immunoprecipitation of the Mouse Mx1 Protein with the Influenza A Virus Nucleoprotein

An Optimized Method for Isolating and Expanding Invariant Natural Killer T Cells from Mouse Spleen

Intra-tracheal Administration of Haemophilus influenzae in Mouse Models to Study Airway Inflammation

Mouse Body Temperature Measurement Using Infrared Thermometer During Passive Systemic Anaphylaxis and Food Allergy Evaluation

A Controlled Mouse Model for Neonatal Polymicrobial Sepsis