We thank Dr. Erica P. Cai and Dr. Yuki Ishikawa for developing the method described in this protocol (see ref. 11). Research in S.K. and P.Y.&#39;s laboratories is supported by grants from the National Institutes of Health (NIH) (R01DK120445, P30DK036836), JDRF, the Harvard Stem Cell Institute, and the Beatson Foundation. T.S. was supported by a postdoctoral fellowship from the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) (T32 DK007260-45), and K.B. was supported in part by a fellowship from the Mary K. Iacocca Foundation.

<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/64836/64836fig01.jpg" /> 
Figure 1: The workflow for transplanting and imaging grafts in an adoptive transfer model of diabetes in mice. NIT-1 cells expressing the firefly transgene luciferase (luc2) are transplanted subcutaneously into NOD-scid mice. The mice are simultaneously injected with autoreactive splenocytes isolated from a spontaneously diabetic NOD mouse. The grafts are imaged at regular intervals by non-invasive bioluminescent imaging. Figure created by BioRender.com. Abbreviations: NOD = non-obese diabetic; scid = severe combined immunodeficient. <a href="https://www.jove.com/files/ftp_upload/64836/64836fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
All animal care and study protocols were approved by and performed in accordance with the Institutional Animal Care and Use Committee (IACUC) at the Joslin Diabetes Center. NOD and NOD-scid mice may be readily obtained from commercial sources. All mice in this study are maintained in a sentinal-monitored facility. See the Table of Materials for details related to all the materials, animals, instruments, and software used in this protocol.
1. Engineering and maintenance of NIT-1 cell lines
<ol>
	<li>Maintain NIT-1 cell lines, which share a genetic background with NOD mice, and 293FT cells in tissue culture-treated dishes in DMEM containing 4.5 g/L glucose supplemented with 10% fetal bovine serum and 1% penicillin/streptomycin in a 37 &#176;C incubator with 5% CO2.</li>
	<li>Grow the 293FT cells to 70%-80% confluence for transfection.</li>
	<li>Per 10 cm dish of 293FT cells, combine 10 &#181;g of pLenti-luciferase-blast (see Supplemental File 1), which expresses the firefly luciferase transgene (luc2) under the control of the constitutively active EF1&#945; promotor, 2 &#181;g each of the packaging plasmids pMD2.G, pMDLg/pRRE, and pRSV-Rev, 4 &#181;g of the envelope protein plasmid pCMV-VSV-G, and 60 &#181;g of linear polyethylenimine (PEI) in 1 mL of serum-free DMEM. Adjust the amounts based on the number of cells to be transfected.</li>
	<li>Leave the DNA, PEI, and DMEM at room temperature (RT) for 20 min, and then add them to the 293FT cells.</li>
	<li>Collect the medium containing the lentiviral particles 48 h post transfection.</li>
	<li>Transduce the NIT-1 cells at ~80% confluency with 1 mL of medium containing lentiviral particles per 106 cells for 48-72 h.</li>
	<li>Select the luciferase-expressing cells with 5 &#181;g/mL blasticidin for 48 h.</li>
	<li>Further genetically modify the luciferase-expressing cells to suit the experimental question. Include a luciferase-expressing wild-type or non-targeting control cell line for comparison. 
	NOTE: Examples of target gene modifications include CRISPR knockout, CRISPRa/i, shRNA knockdown, and overexpression.</li>
</ol>
2. Preparation of NIT-1 cells for transplant
<ol>
	<li>Grow the luciferase-expressing cells until they are 80%-90% confluent.</li>
	<li>Remove the growth medium and wash the cells with phosphate-buffered saline (PBS, 5 mL for a 10 cm dish).</li>
	<li>Add 1 mL of 0.05% trypsin-EDTA to each dish for 2 min.</li>
	<li>Neutralize the trypsin with 5 mL of growth medium.</li>
	<li>Use a pipette to wash the cells off the dish and transfer them to a conical tube. 
	NOTE: Cells from multiple dishes of the same cell line can be combined.</li>
	<li>Count the cells using a stain such as trypan blue manually with a hemocytometer or automatically with an automatic cell counter.</li>
	<li>Centrifuge at 250 &#215; g for 5 min at RT and remove the supernatant with an aspirating pipette.</li>
	<li>Resuspend the cell pellet in PBS at a concentration of 5 &#215; 107 cells/mL (107 cells per cell line per mouse will be transplanted in a volume of 200 &#181;L).</li>
	<li>Keep the cells on ice (for up to 3 h) until transplantation.</li>
</ol>
3. Transplantation of NIT-1 cells into NOD-scid mice
<ol>
	<li>Anesthetize the recipient mice (8-10-week-old NOD-scid mice of the same sex as the mice used to isolate the splenocytes) by isoflurane inhalation in a knockdown chamber. Deliver 2.5% isoflurane into the chamber at a flow rate of 1.5 L/min and an evacuation rate of 9 L/min.&#160;</li>
	<li>Lubricate the animal&#39;s eyes with ophthalmic ointment to prevent drying.</li>
	<li>Using an electric shaver with a guard, remove the hair from the back (dorsal side) of the mice to expose the skin. The shaved transplant area will be approximately 1 in x 2 in. Return the shaved mice to the knockdown chamber until the transplant.</li>
	<li>Transfer the mice one at a time to a clean surface with an isoflurane nose cone. Gently guide the mouse&#39;s head into the nose cone. Use an isoflurane flow rate of 0.25 L/min to maintain the anesthesia during the transplant.</li>
	<li>Wipe the transplant area with an isopropyl alcohol prep pad to remove loose hair and disinfect the skin.</li>
	<li>Ensure the cells are fully resuspended before loading the syringe. Draw an excess volume (&#62;300 &#181;L) of cells into a 1 mL sterile syringe with a 26 G needle. Remove any bubbles; then, return excess cells to the tube so that 300 &#181;L of cell suspension remains in the syringe.</li>
	<li>Using a pair of curved forceps held in the non-dominant hand, gently lift the skin on one side (left or right) of the mouse&#39;s back to allow for easier access to the subcutaneous space.</li>
	<li>Using the dominant hand, position the syringe parallel to the coronal and sagittal planes of the mouse&#39;s body. With the needle pointed toward the head of the mouse, insert the needle into the skin near the hindquarters, and gently guide it into the subcutaneous space. Ensure that the entire needle remains under the skin and does not poke through.</li>
	<li>Adjust the forceps to gently hold the skin around the base of the needle. Slowly dispense a small amount of cell suspension (&#60;50 &#181;L) and confirm that a small bulge forms under the skin at the site of the injection. Continue injecting the cell suspension until 200 &#181;L has been delivered to the subcutaneous space.</li>
	<li>Holding the forceps in place and keeping the needle parallel to the mouse&#39;s body, slowly withdraw the needle. After the needle has been removed, hold the skin closed with forceps for a few seconds to prevent the cells from leaking out of the puncture wound.</li>
	<li>If a genetic modification is being evaluated, repeat the transplant on the opposite side of the mouse using a different syringe so that both mutant and control cells are injected into each mouse, with one cell line on the left and the other on the right. If only one cell line is being transplanted, inject the cells on one side only.</li>
	<li>Following the transplant, transfer each mouse to a fresh cage. Allow each mouse to fully recover from the anesthesia before adding additional mice to the cage. 
	NOTE: Mice are recovered when they resume normal activities and do not show signs of lethargy or impaired movement.</li>
	<li>Evaluate the health status of the mice daily for the duration of the experiment following the transplant. If the grafts form a large bulge or the mice become weak and lethargic, measure their blood glucose and provide 10% (w/w) sucrose water ad libitum to all the hypoglycemic mice. Follow all veterinary recommendations and euthanize any mice with continued poor body condition as per institutional guidelines. In this study, mice were euthanized by CO2 inhalation followed by cervical dislocation.</li>
</ol>
4. Isolation and purification of autoreactive splenocytes
<ol>
	<li>Identify 10-16-week-old male or female NOD mice with recent-onset (less than 10 days) diabetes by using urine (or blood) glucose test strips. NOD mice are considered diabetic when they have urine/blood glucose &#8805;250 mg/dL on at least 2 consecutive days. 
	NOTE: For each NOD-scid mouse, 10 million splenocytes are needed; one spleen typically yields 50 million to 150 million splenocytes.&#160;The splenocytes were isolated from pathogen-free mice housed in a sentinal-monitored facility.</li>
	<li>Euthanize the appropriate number of diabetic NOD mice. 
	NOTE: In this study, the mice were euthanized by CO2 inhalation followed by cervical dislocation to ensure death.</li>
	<li>With the mouse on its back, make a vertical incision approximately 2 in in length in the skin with surgical scissors. Open the right side of the mouse from the researcher&#39;s point of view and locate the bright red spleen. Gently cut the spleen away from the pink pancreas and transfer it to a sterile 10 cm Petri dish containing 5 mL of sterile PBS. Repeat the dissection with as many mice as needed. 
	NOTE: Spleens from multiple mice can be combined in one dish. Conduct the following steps using sterile reagents and equipment in a sterile hood.</li>
	<li>Mash the spleen(s) with the flat top of a sterile syringe plunger.</li>
	<li>Place a 40 &#181;m or 70 &#181;m strainer in a 50 mL conical tube and wash the strainer with 5 mL of PBS to prime it. Transfer the spleen(s) suspension into the strainer and continue gentle mashing through the strainer. Wash the dish with 10 mL of PBS and transfer the wash to the strainer. Continue mashing until the red color is gone from the strainer.</li>
	<li>Discard the strainer and spin the tube at 500 &#215; g for 5 min at RT. Remove the supernatant with an aspirating pipette.</li>
	<li>Resuspend the cell pellet in 5 mL (for up to three spleens) of ACK lysis buffer prewarmed to RT and lyse the red blood cells for 4 min. Increase the volume by 1-2 mL per spleen if additional spleens are needed.</li>
	<li>Stop the reaction with 5 mL of NIT-1 cell media (described above) per 5 mL of lysis buffer. Pass the cell suspension through a fresh strainer to remove clumps. Discard the strainer, and spin at 500 &#215; g for 5 min at RT.</li>
	<li>Resuspend the cell pellet in 20 mL of PBS, and count the cells. Spin at 500 &#215; g for 5 min at RT. Resuspend the cells in sterile PBS at a concentration of 1 &#215; 108 cells/mL (the injection volume is 0.1 mL/mouse) in a 1.5 mL safe-lock reaction tube.</li>
	<li>Store the cells on ice (for not more than 1 h) or keep the cells at RT, and proceed to the tail vein injection immediately.</li>
</ol>
5. Intravenous injection of diabetic splenocytes via the lateral tail vein
<ol>
	<li>Warm up the body of the adult recipient NOD-scid mice (e.g., by using a heat lamp for ~5-10 min) to vasodilate the veins (this helps for visualization and injection into the vein). 
	NOTE: To avoid the overheating of the mice, do not exceed this time. Always monitor the health status. If the mice appear exhausted or immobile, shut off the heat lamp immediately.</li>
	<li>Warm up the cell suspension. Prepare a sterile syringe (0.3-1.0 mL) with a sterile needle (27-30 G, 0.3 mm/0.5 in or smaller), or use a sterile 0.5 mL insulin syringe with a 0.3 mm (0.5 in) needle. Always keep the needle sterile and use a sterile tray if the syringe must be put down between injections.</li>
	<li>Resuspend the splenocyte solution prior to each injection. For each mouse, draw 100 &#181;L of the prewarmed and mixed splenocyte suspension into the syringe. Make sure that no air bubbles are present in the syringe or in the suspension. 
	NOTE: Make sure to have all the equipment and supplies prepared (alcohol wipes for disinfection, a syringe loaded with the splenocytes to be injected, and a fresh cage for separating injected mice) before placing the mouse in the restraint device.</li>
	<li>Place the mouse in the restraint device. Capture the tail with the non-dominant hand and locate one of the two lateral tail veins. Gently rotate the tail if needed. Wipe the tail with a disinfection wipe (70% isopropyl alcohol) to clean the skin and increase the visibility of the vein.</li>
	<li>Insert the needle at an acute angle into the central region of the tail with the dominant hand. With the bevel of the needle facing up, slide the needle a few millimeters through the skin. 
	NOTE: Make sure the needle is parallel to the vein and placed just slightly under the skin. Be prepared for sudden movements of the mouse/tail directly after penetrating the skin/vessel wall. A successful insertion of the needle should feel like a &#34;smooth slide&#34; into the vein. If another attempt is needed, move further up the tail toward the body.</li>
	<li>Apply gentle pressure to the syringe to inject the splenocyte suspension. Do not allow the needle to move further in or out when injecting. Successful injections are smooth without feeling any back pressure during injection and are indicated by a transparent/white blood flow immediately following injection.</li>
	<li>Gently release the needle out of the vein, and apply light pressure to the tail with a disinfection wipe until the bleeding stops. Release the mouse from the restraint device, and gently transfer it to a freshly prepared cage. 
	NOTE: Inject two to three control mice that do not receive a NIT-1 cell transplant with splenocytes to confirm the potential of the autoreactive splenocytes to induce diabetes, which takes approximately 2-4 weeks post injection.</li>
</ol>
6. In vivo bioluminescent imaging of NIT-1 grafts
NOTE: Image the grafts one to two times per week. On the day of the transplant, wait at least 2 h after the transplant to allow the grafts to settle and ensure stable luciferase expression. If time is a limiting factor, the initial measurement may be taken on Day 1 instead. A recommended initial imaging schedule is Day 0 or Day 1 post injection, Day 5, Day 10, Day 14, Day 18, and Day 25. Adjust the schedule, however, based on the progress of autoimmunity as judged by the loss of bioluminescent signal.
<ol>
	<li>Prepare a 15 mg/mL D-luciferin solution in Dulbecco&#39;s PBS. Agitate at RT to dissolve, and sterile-filter (0.22 &#181;m). Store 1 mL aliquots at &#8722;20 &#176;C, and thaw as needed. 
	NOTE: The aliquots can be refrozen.</li>
	<li>At least 5 min prior to imaging, inject the mice intraperitoneally using a 1 mL syringe and a 26 G needle with D-luciferin solution at a dose of 150 mg/kg.&#160; 
	NOTE: Use a fresh syringe and needle for each mouse.&#160;</li>
	<li>Anesthetize the mice by isoflurane inhalation according to institutional guidelines. The recommended conditions are 2.5% isoflurane with a flow rate of 1.5 L/min into the knockdown chamber and an evacuation rate of 9 L/min.</li>
	<li>Lubricate the animal&#39;s eyes with ophthalmic ointment to prevent drying.</li>
	<li>Open the software associated with the imaging instrument. Create a new user and/or login. On the control panel on the bottom right, select Initialize (Figure 2A). To auto-save the imaging data, create the appropriate folders on the computer, and then select Acquisition | Auto-save to&#8230; (Figure 2A). Once the instrument has finished initializing, set the exposure time to 1 min. 
	NOTE: The complete imaging parameters are shown in Figure 2B.</li>
	<li>Transfer the mice one at a time from the knockdown chamber to the imaging instrument. Place the mouse on its stomach with its limbs splayed, and gently guide its head into the nose cone. An isoflurane flow rate of 0.25 L/min delivered via a nose cone is appropriate to maintain anesthesia during imaging. Gently flatten the mouse by pressing the center of its back with both hands and then spreading the hands outward and apart.</li>
	<li>Select Acquire (Figure 2B). Record any relevant details of the experiment in the pop-up window (Figure 2C). 
	NOTE: See Figure 3A for representative images of three 8-week-old female NOD-scid mice transplanted with two grafts at various time points.</li>
</ol>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/64836/64836fig02.jpg" /> 
Figure 2: Screenshots of the software commands for imaging bioluminescent grafts. (A) Prior to imaging, select Initialize to prepare the instrument. The images may be auto-saved to a folder of choice by selecting Acquisition | Auto-save to&#8230; (B) Overview of the imaging parameters. Once the mouse has been positioned in the instrument, select Acquire. (C) Screenshot of the dialog box that pops up during imaging. Details such as the time point and mouse strain may be entered here. <a href="https://www.jove.com/files/ftp_upload/64836/64836fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
7. Data analysis
<ol>
	<li>Quantify the bioluminescent signal at any time after imaging. Open the software associated with the imaging instrument. Select File | Open, and select the ClickInfo.txt file associated with the mouse to be analyzed.</li>
	<li>In the Tool Palette, select ROI Tools (Figure 3B, Step 1). From the oval dropdown menu (Figure 3B, Step 1, red arrow), select the number of grafts that were transplanted into the mouse.</li>
	<li>Move the ovals so that they contain the bioluminescent signal from each graft, and select Measure ROIs (Figure 3B, Step 2).</li>
	<li>Record the Total Count for each graft (Figure 3B, Step 3).</li>
	<li>For each graft, divide the bioluminescent signal measured at every time point by the signal measured at the first time point. Report the graft survival as the proportion or percentage of residual bioluminescent signal relative to the initial bioluminescent signal. 
	NOTE: If the grafts expand post transplant, the ratio or percentage of graft survival will be greater than 1 or 100%, respectively. All the mice that receive transplants should be monitored for adverse health effects.</li>
</ol>

<ol>
	<li>Katsarou, A., 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=Type+1+diabetes+mellitus.">Type 1 diabetes mellitus.</a> Nature Reviews Disease Primers. 3, 17016 (2017).</li><li>Shapiro, A. M., Pokrywczynska, M., Ricordi, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clinical+pancreatic+islet+transplantation.">Clinical pancreatic islet transplantation.</a> Nature Reviews Endocrinology. 13 (5), 268-277 (2017).</li><li>Pagliuca, F. W., 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=Generation+of+functional+human+pancreatic+beta+cells+in+vitro.">Generation of functional human pancreatic beta cells in vitro.</a> Cell. 159 (2), 428-439 (2014).</li><li>Russ, H. A., 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=Controlled+induction+of+human+pancreatic+progenitors+produces+functional+beta-like+cells+in+vitro.">Controlled induction of human pancreatic progenitors produces functional beta-like cells in vitro.</a> EMBO Journal. 34 (13), 1759-1772 (2015).</li><li>Rezania, A., 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=Reversal+of+diabetes+with+insulin-producing+cells+derived+in+vitro+from+human+pluripotent+stem+cells.">Reversal of diabetes with insulin-producing cells derived in vitro from human pluripotent stem cells.</a> Nature Biotechnology. 32 (11), 1121-1133 (2014).</li><li>Vertex Announces Positive Day 90 Data for the First Patient in the Phase 1_2 Clinical Trial Dosed With VX-880, a Novel Investigational Stem Cell-Derived Therapy for the Treatment of Type 1 Diabetes. Businesswire Available from: <a target="_blank" href="https://www.businesswire.com/news/home/20211018005226/en/Vertex-Announces-Positive-Day-90-Data-for-the-First-Patient-in-the-Phase-12-Clinical-Trial-Dosed-With-VX-880-a-Novel-Investigational-Stem-Cell-Derived-Therapy-for-the-Treatment-of-Type-1-Diabetes">https://www.businesswire.com/news/home/20211018005226/en/Vertex-Announces-Positive-Day-90-Data-for-the-First-Patient-in-the-Phase-12-Clinical-Trial-Dosed-With-VX-880-a-Novel-Investigational-Stem-Cell-Derived-Therapy-for-the-Treatment-of-Type-1-Diabetes</a> (2021)</li><li>Gamble, A., Pepper, A. R., Bruni, A., Shapiro, A. M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+journey+of+islet+cell+transplantation+and+future+development.">The journey of islet cell transplantation and future development.</a> Islets. 10 (2), 80-94 (2018).</li><li>Pearson, J. A., Wong, F. S., Wen, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+importance+of+the+Non+Obese+Diabetic+(NOD)+mouse+model+in+autoimmune+diabetes.">The importance of the Non Obese Diabetic (NOD) mouse model in autoimmune diabetes.</a> Journal of Autoimmunity. 66, 76-88 (2016).</li><li>Hamaguchi, K., Gaskins, R. H., Leiter, E. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=NIT-1,+a+pancreatic+&#946;-cell+line+established+from+a+transgenic+NOD/Lt+mouse.">NIT-1, a pancreatic &#946;-cell line established from a transgenic NOD/Lt mouse.</a> Diabetes. 40 (7), 842-849 (1991).</li><li>Christianson, S. W., Shultz, L. D., Leiter, E. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adoptive+transfer+of+diabetes+into+immunodeficient+NOD-scid/scid+mice:+Relative+contribution+of+CD4++and+CD8++T-cells+from+diabetogenic+versus+prediabetic+NOD.NON-Thy1a+donors.">Adoptive transfer of diabetes into immunodeficient NOD-scid/scid mice: Relative contribution of CD4+ and CD8+ T-cells from diabetogenic versus prediabetic NOD.NON-Thy1a donors.</a> Diabetes. 42 (1), 44-55 (1993).</li><li>Cai, E. P., 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=Genome-scale+in+vivo+CRISPR+screen+identifies+RNLS+as+a+target+for+beta+cell+protection+in+type+1+diabetes.">Genome-scale in vivo CRISPR screen identifies RNLS as a target for beta cell protection in type 1 diabetes.</a> Nature Metabolism. 2 (9), 934-945 (2020).</li><li>Parent, A. V., 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=Selective+deletion+of+human+leukocyte+antigens+protects+stem+cell-derived+islets+from+immune+rejection.">Selective deletion of human leukocyte antigens protects stem cell-derived islets from immune rejection.</a> Cell Reports. 36 (7), 109538 (2021).</li><li>Brehm, M. A., 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=Lack+of+acute+xenogeneic+graft-versus-host+disease,+but+retention+of+T-cell+function+following+engraftment+of+human+peripheral+blood+mononuclear+cells+in+NSG+mice+deficient+in+MHC+class+I+and+II+expression.">Lack of acute xenogeneic graft-versus-host disease, but retention of T-cell function following engraftment of human peripheral blood mononuclear cells in NSG mice deficient in MHC class I and II expression.</a> FASEB Journal. 33 (3), 3137-3151 (2019).</li><li>Abdulreda, M. H., 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=In+vivo+imaging+of+type+1+diabetes+immunopathology+using+eye-transplanted+islets+in+NOD+mice.">In vivo imaging of type 1 diabetes immunopathology using eye-transplanted islets in NOD mice.</a> Diabetologia. 62 (7), 1237-1250 (2019).</li></ol>

The authors declare that they have no conflicts of interest.

T1D is a devastating disease for which no cure currently exists. Beta cell replacement therapy offers a promising treatment for patients with this disease, but the critical barrier to this strategy is the potential for recurrent autoimmune attack against the transplanted beta cells. The genetic engineering of SC-beta cells to reduce their immune visibility or susceptibility is one potential solution to this problem. Described here is a protocol for non-invasively imaging transplanted beta cells to measure their survival ...

Type 1 diabetes (T1D) is caused by the autoimmune destruction of the insulin-producing beta cells of the pancreas. The loss of beta cell mass results in insulin deficiency and hyperglycemia. T1D patients rely on multiple daily injections of exogenous insulin and experience episodes of severe hyperglycemia and hypoglycemia throughout their lives. The complications related to these episodes include diabetic retinopathy, decreased kidney function, and neuropathy1.
Insulin injections are a treatment but not a cure for T1D. Replacing the lost beta cell mass, however, has the potential to reverse the disease by enabling patients to produce their own insulin. However, the supply of cadaveric donor islets is limited2. Stem cell-derived islets (SC-islets) may provide a virtually unlimited supply of beta cells for transplant. Several groups have demonstrated that human embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) can be differentiated to generate functional beta-like cells3,4,5. Promising early clinical trial data indicate that these cells maintain their function following transplant and may enable patients to become insulin-independent6. Chronic immunosuppression is required, however, thus increasing their susceptibility to cancer and infection. In addition, immunosuppressive agents may be cytotoxic to grafts in the long term7. To eliminate the need for immunosuppression, SC-islets may be genetically modified to protect them from recurrent autoimmunity as well as alloimmunity after transplant.
Stem cell research is highly demanding in costs and labor. Mouse cell lines and animal models are useful tools for the initial identification and experimental validation of strategies to protect transplanted cells from autoimmunity. The NOD mouse develops spontaneous autoimmune diabetes with many similarities to human T1D8, and the NIT-1 insulinoma cell line shares a genetic background with this mouse strain9. Diabetes can be adoptively transferred to the related immunodeficient NOD-scid mouse strain via the injection of diabetic splenocytes from NOD mice in order to temporally synchronize the onset of diabetes in replicate experimental mice10. This model can be used to identify genetic targets relatively quickly and inexpensively for further validation in SC-islets. Recently, the method was applied to identify and validate RNLS, a target that was found to protect primary human islets from autoimmunity in vivo and iPSC-derived islets from beta cell stress in vitro11. Described here is a straightforward protocol to transplant genetically engineered NIT-1 cells and non-invasively monitor their survival in an adoptive transfer model of autoimmune diabetes in mice.

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		<tr>
			<td>0.05% Trypsin, 0.53 mM EDTA</td>
			<td>Corning</td>
			<td>25-052-CI</td>
			<td></td>
		</tr>
		<tr>
			<td>293FT</td>
			<td>Invitrogen</td>
			<td>R70007</td>
			<td>Fast-growing, highly transfectable clonal isolate derived from human embryonal kidney cells transformed with the SV40 large T antigen</td>
		</tr>
		<tr>
			<td>ACK Lysing Buffer</td>
			<td>Gibco</td>
			<td>A10492-01</td>
			<td></td>
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			<td>Alcohol prep pads, 70% Isopropyl alcohol</td>
			<td>Amazon/Ever Ready First Aid</td>
			<td>B08NWF31DX</td>
			<td></td>
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		<tr>
			<td>BD 5ml Syringe Luer-Lok Tip</td>
			<td>BD</td>
			<td>309646</td>
			<td></td>
		</tr>
		<tr>
			<td>BD PrecisionGlide Needle 26G x 5/8 (0.45 mm x 16 mm) Sub-Q</td>
			<td>BD</td>
			<td>305115</td>
			<td></td>
		</tr>
		<tr>
			<td>BD 1 mL TB Syringe Slip Tip</td>
			<td>BD</td>
			<td>309659</td>
			<td></td>
		</tr>
		<tr>
			<td>Blasticidin S HCl</td>
			<td>Corning</td>
			<td>&#160;30-100-RB</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell strainer premium SureStrain, 70 &#181;m, sterile</td>
			<td>Southern Labware</td>
			<td>C4070</td>
			<td>Or use similar sterile strainer with 40-70um pore size</td>
		</tr>
		<tr>
			<td>CellDrop automated cell counter</td>
			<td>Denovix</td>
			<td>CellDrop BF-PAYG</td>
			<td>Or use similar cell counter device</td>
		</tr>
		<tr>
			<td>Corning 100 mL Penicillin-Streptomycin Solution, 100x</td>
			<td>Corning</td>
			<td>30-002-CI</td>
			<td></td>
		</tr>
		<tr>
			<td>Disposable Aspirating Pipets, Polystyrene, Sterile, Capacity=2 mL</td>
			<td>VWR</td>
			<td>414004-265</td>
			<td>Or use similar aspirating pipette</td>
		</tr>
		<tr>
			<td>D-Luciferin, Potassium Salt , Molecular Biology Grade, Powder, &#62;99%</td>
			<td>Goldbio</td>
			<td>LUCK-100</td>
			<td></td>
		</tr>
		<tr>
			<td>DMEM, high glucose, pyruvate, no glutamine</td>
			<td>Gibco</td>
			<td>10313039</td>
			<td></td>
		</tr>
		<tr>
			<td>Falcon BD tubes, 50 mL</td>
			<td>Fisher Scientific</td>
			<td>14-959-49A</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum</td>
			<td>Gibco</td>
			<td>10437-028</td>
			<td></td>
		</tr>
		<tr>
			<td>Forceps premium for tissues, 1 x 2 teeth 5 in, German Steel</td>
			<td>Fisher Scientific</td>
			<td>13-820-074</td>
			<td></td>
		</tr>
		<tr>
			<td>Glucose urine test strip</td>
			<td>California Pet Pharmacy</td>
			<td>u-tsg100</td>
			<td>Or use similar test strip for glucose measurments in urine/blood</td>
		</tr>
		<tr>
			<td>GlutaMAX&#8211;1 (100x)</td>
			<td>Gibco</td>
			<td>35050-061</td>
			<td></td>
		</tr>
		<tr>
			<td>Infrared heating lamp</td>
			<td>Cole Parmer</td>
			<td>03057-00</td>
			<td>Or use similar infrared lamp&#160;</td>
		</tr>
		<tr>
			<td>Insulin syringe 0.5 mL, U-100 29 G 0.5 in</td>
			<td>Becton Dickinson</td>
			<td>309306</td>
			<td></td>
		</tr>
		<tr>
			<td>Isoflurane, USP</td>
			<td>Piramal Critical Care</td>
			<td>6679401725</td>
			<td></td>
		</tr>
		<tr>
			<td>IVIS Spectrum in vivo imaging system</td>
			<td>Perkin Elmer</td>
			<td>124262</td>
			<td>Instrument for non-invasively collecting bioluminescent images of transplanted cells</td>
		</tr>
		<tr>
			<td>Living Image Analysis Software</td>
			<td>Perkin Elmer</td>
			<td>128113</td>
			<td>Software for collecting and quantifying bioluminescent signal</td>
		</tr>
		<tr>
			<td>Microcentrifuge tubes seal-rite, 1.5 mL</td>
			<td>USA Scientific</td>
			<td>1615-5510</td>
			<td>Or use similar sterile microcentrifuge tubes</td>
		</tr>
		<tr>
			<td>NIT-1</td>
			<td>ATCC</td>
			<td>CRL-2055</td>
			<td>Pancreatic beta-celll line derived from NOD/Lt mice</td>
		</tr>
		<tr>
			<td>NOD.Cg-Prkdcscid/J</td>
			<td>The Jackson Laboratory</td>
			<td>001303</td>
			<td>Mice homozygous for the severe combined immune deficiency spontaneous mutation&#160;Prkdcscid, commonly referred to as&#160;scid, are characterized by an absence of functional T cells and B cells, lymphopenia, hypogammaglobulinemia, and a normal hematopoietic microenvironment.</td>
		</tr>
		<tr>
			<td>NOD/ShiLtJ</td>
			<td>The Jackson Laboratory</td>
			<td>001976</td>
			<td>The NOD/ShiLtJ strain of mice (commonly called NOD) is a polygenic model for autoimmune type 1 diabetes</td>
		</tr>
		<tr>
			<td>PBS, pH 7.4</td>
			<td>Thermo Fisher Scientific</td>
			<td>10010031</td>
			<td>No calcium, no magnesium, no phenol red</td>
		</tr>
		<tr>
			<td>pCMV-VSV-G</td>
			<td>Addgene</td>
			<td>8454</td>
			<td></td>
		</tr>
		<tr>
			<td>pLenti-luciferase-blast</td>
			<td>Made in-house</td>
			<td>Plasmid available upon request</td>
			<td>See Supplemental File 1</td>
		</tr>
		<tr>
			<td>pMD2.G</td>
			<td>Addgene</td>
			<td>12259</td>
			<td></td>
		</tr>
		<tr>
			<td>pMDLg/pRRE</td>
			<td>Addgene</td>
			<td>12251</td>
			<td></td>
		</tr>
		<tr>
			<td>Polyethylenimine, Linear, MW 25,000, Transfection Grade (PEI 25K)</td>
			<td>Fisher Scientific</td>
			<td>NC1014320</td>
			<td></td>
		</tr>
		<tr>
			<td>pRSV-Rev</td>
			<td>Addgene</td>
			<td>12253</td>
			<td></td>
		</tr>
		<tr>
			<td>Restrainer for rodents, broome-style round 1 in</td>
			<td>Fisher Scientific</td>
			<td>01-288-32A</td>
			<td></td>
		</tr>
		<tr>
			<td>Scissors, sharp-pointed</td>
			<td>Fisher Scientific</td>
			<td>08-940</td>
			<td>Or use other scissors made of surgical-grade stainless steel</td>
		</tr>
		<tr>
			<td>Tissue-culture treated culture dishes</td>
			<td>Millipore Sigma</td>
			<td>CLS430167-20EA</td>
			<td>Or use other sterile cell culture-treated Petri dishes</td>
		</tr>
		<tr>
			<td>Tweezers/Forceps, fine precision medium tipped</td>
			<td>Fisher Scientific</td>
			<td>12-000-157</td>
			<td></td>
		</tr>
	</tbody>
</table>

bioluminescent monitoring of graft survival in an adoptive transfer model of autoimmune diabetes in mice

Type 1 diabetes is characterized by the autoimmune destruction of the insulin-producing beta cells of the pancreas. A promising treatment for this disease is the transplantation of stem cell-derived beta cells. Genetic modifications, however, may be necessary to protect the transplanted cells from persistent autoimmunity. Diabetic mouse models are a useful tool for the preliminary evaluation of strategies to protect transplanted cells from autoimmune attack. Described here is a minimally invasive method for transplanting and imaging cell grafts in an adoptive transfer model of diabetes in mice. In this protocol, cells from the murine pancreatic beta cell line NIT-1 expressing the firefly luciferase transgene luc2 are transplanted subcutaneously into immunodeficient non-obese diabetic (NOD)-severe combined immunodeficient (scid) mice. These mice are simultaneously injected intravenously with splenocytes from spontaneously diabetic NOD mice to transfer autoimmunity. The grafts are imaged at regular intervals via non-invasive bioluminescent imaging to monitor the cell survival. The survival of mutant cells is compared to that of control cells transplanted into the same mouse.

An overview of the protocol is outlined in Figure 1. The survival of two cell lines, such as a mutant and a non-targeting control, may be compared, or the survival of one cell line may be measured in multiple groups of mice, such as drug-treated mice versus vehicle-treated controls. Figure 3A shows three 8-week-old female NOD-scid mice transplanted with a non-targeting control (left) and a mutant (right) cell line. The mice were also injected intravenously with ...

Watch this Scientific Journal Video about Bioluminescent Monitoring of Graft Survival in an Adoptive Transfer Model of Autoimmune Diabetes in Mice at JoVE.com

Bioluminescent Monitoring of Graft Survival in an Adoptive Transfer Model of Autoimmune Diabetes in Mice

This protocol describes a straightforward and minimally invasive method for transplanting and imaging NIT-1 cells in non-obese diabetic (NOD)-severe combined immunodeficient mice challenged with splenocytes purified from spontaneously diabetic NOD mice.

Type 1 diabetes is characterized by the autoimmune destruction of the insulin-producing beta cells of the pancreas. A promising treatment for this disease ...

bioluminescent-monitoring-graft-survival-an-adoptive-transfer-model

Research

JoVE Journal

Biology

1.7K Views.  Harvard Medical School. This protocol describes a straightforward and minimally invasive method for transplanting and imaging NIT-1 cells in non-obese diabetic (NOD)-severe combined immunodeficient mice challenged with splenocytes purified from spontaneously diabetic NOD mice.

Video: Bioluminescent Monitoring of Graft Survival in an Adoptive Transfer Model of Autoimmune Diabetes in Mice

Induction and Monitoring of Adoptive Delayed-Type Hypersensitivity in Rats

Delayed type hypersensitivity (DTH) is an inflammatory reaction mediated by CCR7- effector memory T lymphocytes that infiltrate the site of injection of an antigen against which the immune system has been primed. The inflammatory reaction is characterized by redness and swelling of the site of antigenic challenge. It is a convenient model to determine the in vivo efficacy of immunosuppressants. Cutaneous DTH can be induced either by adoptive transfer of antigen-specific T lymphocytes or by active immunization with an antigen, and subsequent intradermal challenge with the antigen to induce the inflammatory reaction in a given skin area. DTH responses can be induced to various antigens, for example ovalbumin, tuberculin, tetanus toxoid, or keyhole limpet hemocyanin. Such reactions can also be induced against autoantigen, for example to myelin basic protein (MBP) in rats with experimental autoimmune encephalomyelitis induced with MBP, an animal model for multiple sclerosis (1).
Here we demonstrate how to induce an adoptive DTH reaction in Lewis rats. We will first stimulate ovalbumin-specific T cells in vitro and inject these activated cells intraperitoneally to naive rats. After allowing the cells to equilibrate in vivo for 2 days, we will challenge the rats with ovalbumin in the pinna of one ear, while the other ear wil receive saline. The inflammatory reaction will be visible 3-72 hours later and ear thickness will be measured as an indication of DTH severity.

Delayed type hypersensitivity (DTH) is an inflammatory reaction mediated by CCR7- effector memory T (TEM) lymphocytes. Here we demonstrate how to activate antigen-specific TEM cells, induce adoptive DTH in Lewis rats and monitor the inflammatory response.

Delayed type hypersensitivity (DTH) is an inflammatory reaction mediated by CCR7- effector memory T lymphocytes that infiltrate the site of injection of ...

In vivo Bioluminescent Imaging of Mammary Tumors Using IVIS Spectrum

4T1 mouse mammary tumor cells can be implanted sub-cutaneously in nu/nu mice to form palpable tumors in 15 to 20 days. This xenograft tumor model system is valuable for the pre-clinical in vivo evaluation of putative antitumor compounds.
The 4T1 cell line has been engineered to constitutively express the firefly luciferase gene (luc2). When mice carrying 4T1-luc2 tumors are injected with Luciferin the tumors emit a visual light signal that can be monitored using a sensitive optical imaging system like the IVIS Spectrum. The photon flux from the tumor is proportional to the number of light emitting cells and the signal can be measured to monitor tumor growth and development. IVIS is calibrated to enable absolute quantitation of the bioluminescent signal and longitudinal studies can be performed over many months and over several orders of signal magnitude without compromising the quantitative result.
Tumor growth can be monitored for several days by bioluminescence before the tumor size becomes palpable or measurable by traditional physical means. This rapid monitoring can provide insight into early events in tumor development or lead to shorter experimental procedures.
Tumor cell death and necrosis due to hypoxia or drug treatment is indicated early by a reduction in the bioluminescent signal. This cell death might not be accompanied by a reduction in tumor size as measured by physical means. The ability to see early events in tumor necrosis has significant impact on the selection and development of therapeutic agents.
Quantitative imaging of tumor growth using IVIS provides precise quantitation and accelerates the experimental process to generate results.

In vivo Bioluminescent Imaging of Mammary Tumors Using IVIS Spectrum

Mammary tumor cells expressing luciferase are implanted subcutaneously in mice and visualized using optical imaging to monitor tumor growth and development non-invasively in a longitudinal study.

4T1 mouse mammary tumor cells can be implanted sub-cutaneously in nu/nu mice to form palpable tumors in 15 to 20 days. This xenograft tumor model system ...

Quantification of &gamma;H2AX Foci in Response to Ionising Radiation

DNA double-strand breaks (DSBs), which are induced by either endogenous metabolic processes or by exogenous sources, are one of the most critical DNA lesions with respect to survival and preservation of genomic integrity. An early response to the induction of DSBs is phosphorylation of the H2A histone variant, H2AX, at the serine-139 residue, in the highly conserved C-terminal SQEY motif, forming &gamma;H2AX1. Following induction of DSBs, H2AX is rapidly phosphorylated by the phosphatidyl-inosito 3-kinase (PIKK) family of proteins, ataxia telangiectasia mutated (ATM), DNA-protein kinase catalytic subunit and ATM and RAD3-related (ATR)2. Typically, only a few base-pairs (bp) are implicated in a DSB, however, there is significant signal amplification, given the importance of chromatin modifications in DNA damage signalling and repair. Phosphorylation of H2AX mediated predominantly by ATM spreads to adjacent areas of chromatin, affecting approximately 0.03% of total cellular H2AX per DSB2,3. This corresponds to phosphorylation of approximately 2000 H2AX molecules spanning ~2 Mbp regions of chromatin surrounding the site of the DSB and results in the formation of discrete &gamma;H2AX foci which can be easily visualized and quantitated by immunofluorescence microscopy2. The loss of &gamma;H2AX at DSB reflects repair, however, there is some controversy as to what defines complete repair of DSBs; it has been proposed that rejoining of both strands of DNA is adequate however, it has also been suggested that re-instatement of the original chromatin state of compaction is necessary4-8. The disappearence of &gamma;H2AX involves at least in part, dephosphorylation by phosphatases, phosphatase 2A and phosphatase 4C5,6. Further, removal of &gamma;H2AX by redistribution involving histone exchange with H2A.Z has been implicated7,8. Importantly, the quantitative analysis of &gamma;H2AX foci has led to a wide range of applications in medical and nuclear research. Here, we demonstrate the most commonly used immunofluorescence method for evaluation of initial DNA damage by detection and quantitation of &gamma;H2AX foci in &gamma;-irradiated adherent human keratinocytes9.

Quantification of &amp;#947;H2AX Foci in Response to Ionising Radiation

Quantification of DNA double-strand streaks using &gamma;H2AX formation as a molecular marker has become an invaluable tool in radiation biology. Here we demonstrate the use of an immunofluorescence assay for quantification of &gamma;H2AX foci after exposure of cells to radiation.

DNA double-strand breaks (DSBs), which are induced by either endogenous metabolic processes or by exogenous sources, are one of the most critical DNA ...

Evaluation of the Spatial Distribution of &gamma;H2AX following Ionizing Radiation

An early molecular response to DNA double-strand breaks (DSBs) is phosphorylation of the Ser-139 residue within the terminal SQEY motif of the histone H2AX1,2. This phosphorylation of H2AX is mediated by the phosphatidyl-inosito 3-kinase (PI3K) family of proteins, ataxia telangiectasia mutated (ATM), DNA-protein kinase catalytic subunit and ATM and RAD3-related (ATR)3. The phosphorylated form of H2AX, referred to as &gamma;H2AX, spreads to adjacent regions of chromatin from the site of the DSB, forming discrete foci, which are easily visualized by immunofluorecence microscopy3. Analysis and quantitation of &gamma;H2AX foci has been widely used to evaluate DSB formation and repair, particularly in response to ionizing radiation and for evaluating the efficacy of various radiation modifying compounds and cytotoxic compounds4.
Given the exquisite specificity and sensitivity of this de novo marker of DSBs, it has provided new insights into the processes of DNA damage and repair in the context of chromatin. For example, in radiation biology the central paradigm is that the nuclear DNA is the critical target with respect to radiation sensitivity. Indeed, the general consensus in the field has largely been to view chromatin as a homogeneous template for DNA damage and repair. However, with the use of &gamma;H2AX as molecular marker of DSBs, a disparity in &gamma;-irradiation-induced &gamma;H2AX foci formation in euchromatin and heterochromatin has been observed5-7. Recently, we used a panel of antibodies to either mono-, di- or tri- methylated histone H3 at lysine 9 (H3K9me1, H3K9me2, H3K9me3) which are epigenetic imprints of constitutive heterochromatin and transcriptional silencing and lysine 4 (H3K4me1, H3K4me2, H3K4me3), which are tightly correlated actively transcribing euchromatic regions, to investigate the spatial distribution of &gamma;H2AX following ionizing radiation8. In accordance with the prevailing ideas regarding chromatin biology, our findings indicated a close correlation between &gamma;H2AX formation and active transcription9. Here we demonstrate our immunofluorescence method for detection and quantitation of &gamma;H2AX foci in non-adherent cells, with a particular focus on co-localization with other epigenetic markers, image analysis and 3D-modeling.

Evaluation of the Spatial Distribution of &amp;#947;H2AX following Ionizing Radiation

Microscopic analysis of &gamma;H2AX foci, which form following the phosphorylation of H2AX at Ser-139 in response to DNA double-strand breaks, has become an invaluable tool in radiation biology. Here we used an antibody to mono-methylated histone H3 at lysine 4 as an epigenetic marker of actively transcribing euchromatin, to evaluate the spatial distribution of radiation-induced &gamma;H2AX formation within the nucleus.

An early molecular response to DNA double-strand breaks (DSBs) is phosphorylation of the Ser-139 residue within the terminal SQEY motif of the histone ...

Long-term Lethal Toxicity Test with the Crustacean Artemia franciscana

Our research activities target the use of biological methods for the evaluation of environmental quality, with particular reference to saltwater/brackish water and sediment. The choice of biological indicators must be based on reliable scientific knowledge and, possibly, on the availability of standardized procedures. In this article, we present a standardized protocol that used the marine crustacean Artemia to evaluate the toxicity of chemicals and/or of marine environmental matrices. Scientists propose that the brine shrimp (Artemia) is a suitable candidate for the development of a standard bioassay for worldwide utilization. A number of papers have been published on the toxic effects of various chemicals and toxicants on brine shrimp (Artemia). The major advantage of this crustacean for toxicity studies is the overall availability of the dry cysts; these can be immediately used in testing and difficult cultivation is not demanded1,2. Cyst-based toxicity assays are cheap, continuously available, simple and reliable and are thus an important answer to routine needs of toxicity screening, for industrial monitoring requirements or for regulatory purposes3. The proposed method involves the mortality as an endpoint. The numbers of survivors were counted and percentage of deaths were calculated. Larvae were considered dead if they did not exhibit any internal or external movement during several seconds of observation4. This procedure was standardized testing a reference substance (Sodium Dodecyl Sulfate); some results are reported in this work. This article accompanies a video that describes the performance of procedural toxicity testing, showing all the steps related to the protocol.

Long-term Lethal Toxicity Test with the Crustacean Artemia franciscana

This study concerns the development and standardization of a valuable methodological protocol to determine long-term (14 days) lethal toxicity exerted by chemical substances, industrial wastewater or sewage and liquid environmental samples on the saltwater crustacean, Artemia franciscana.

Our research activities target the use of biological methods for the evaluation of environmental quality, with particular reference to saltwater/brackish ...

Functional Imaging of Brown Fat in Mice with 18F-FDG micro-PET/CT

Brown adipose tissue (BAT) differs from white adipose tissue (WAT) by its discrete location and a brown-red color due to rich vascularization and high density of mitochondria. BAT plays a major role in energy expenditure and non-shivering thermogenesis in newborn mammals as well as the adults 1. BAT-mediated thermogenesis is highly regulated by the sympathetic nervous system, predominantly via &beta; adrenergic receptor 2, 3. Recent studies have shown that BAT activities in human adults are negatively correlated with body mass index (BMI) and other diabetic parameters 4-6. BAT has thus been proposed as a potential target for anti-obesity/anti-diabetes therapy focusing on modulation of energy balance 6-8. While several cold challenge-based positron emission tomography (PET) methods are established for detecting human BAT 9-13, there is essentially no standardized protocol for imaging and quantification of BAT in small animal models such as mice. Here we describe a robust PET/CT imaging method for functional assessment of BAT in mice. Briefly, adult C57BL/6J mice were cold treated under fasting conditions for a duration of 4 hours before they received one dose of 18F-Fluorodeoxyglucose (FDG). The mice were remained in the cold for one additional hour post FDG injection, and then scanned with a small animal-dedicated micro-PET/CT system. The acquired PET images were co-registered with the CT images for anatomical references and analyzed for FDG uptake in the interscapular BAT area to present BAT activity. This standardized cold-treatment and imaging protocol has been validated through testing BAT activities during pharmacological interventions, for example, the suppressed BAT activation by the treatment of &beta;-adrenoceptor antagonist propranolol 14, 15, or the enhanced BAT activation by &beta;3 agonist BRL37344 16. The method described here can be applied to screen for drugs/compounds that modulate BAT activity, or to identify genes/pathways that are involved in BAT development and regulation in various preclinical and basic studies.

Functional Imaging of Brown Fat in Mice with 18F-FDG micro-PET/CT

A method of functional imaging of mouse brown adipose tissue (BAT) is described in which cold-stimulated uptake of 18F-Fluorodeoxyglucose (FDG) in BAT is non-invasively assessed with a standardized micro-PET/CT protocol. This method is robust and sensitive to detect differences in BAT activities in mouse models.

Brown adipose tissue (BAT) differs from white adipose  tissue (WAT) by its discrete location and a brown-red color due to rich  vascularization and high ...

Autonomously Bioluminescent Mammalian Cells for Continuous and Real-time Monitoring of Cytotoxicity

Mammalian cell-based in vitro assays have been widely employed as alternatives to animal testing for toxicological studies but have been limited due to the high monetary and time costs of parallel sample preparation that are necessitated due to the destructive nature of firefly luciferase-based screening methods. This video describes the utilization of autonomously bioluminescent mammalian cells, which do not require the destructive addition of a luciferin substrate, as an inexpensive and facile method for monitoring the cytotoxic effects of a compound of interest. Mammalian cells stably expressing the full bacterial bioluminescence (luxCDABEfrp) gene cassette autonomously produce an optical signal that peaks at 490 nm without the addition of an expensive and possibly interfering luciferin substrate, excitation by an external energy source, or destruction of the sample that is traditionally performed during optical imaging procedures. This independence from external stimulation places the burden for maintaining the bioluminescent reaction solely on the cell, meaning that the resultant signal is only detected during active metabolism. This characteristic makes the lux-expressing cell line an excellent candidate for use as a biosentinel against cytotoxic effects because changes in bioluminescent production are indicative of adverse effects on cellular growth and metabolism. Similarly, the autonomous nature and lack of required sample destruction permits repeated imaging of the same sample in real-time throughout the period of toxicant exposure and can be performed across multiple samples using existing imaging equipment in an automated fashion.

Mammalian cells expressing the bacterial bioluminescence gene cassette (lux) produce light autonomously. The resulting bioluminescent dynamics upon chemical exposure have been demonstrated to reflect the treatment effects on cellular growth and metabolism, making these cells an inexpensive, continuous, real-time toxicity screening tool that can easily be adapted for high-throughput automation.

Mammalian  cell-based in vitro assays have been  widely employed as alternatives to animal testing for toxicological studies but  have been limited due to ...

Measurement of Survival Time in Brachionus Rotifers: Synchronization of Maternal Conditions

Rotifers are microscopic cosmopolitan zooplankton used as models in ecotoxicological and aging studies due to their several advantages such as short lifespan, ease of culture, and parthenogenesis that enables clonal culture. However, caution is required when measuring their survival time as it is affected by maternal age and maternal feeding conditions. Here we provide a protocol for powerful and reproducible measurement of the survival time in Brachionus rotifers following a careful synchronization of culture conditions over several generations. Empirically, poor synchronization results in early mortality and a gradual decrease in survival rate, thus resulting in weak statistical power. Indeed, under such conditions, calorie restriction (CR) failed to significantly extend the lifespan of B. plicatilis although CR-induced longevity has been demonstrated with well-synchronized rotifer samples in past and present studies. This protocol is probably useful for other invertebrate models, including the fruitfly Drosophila melanogaster and the nematode Caenorhabditis elegans, because maternal age effects have also been reported in these species.

Measurement of Survival Time in Brachionus Rotifers: Synchronization of Maternal Conditions

Rotifers are microscopic zooplankton used as models in ecotoxicological and aging studies. Here we provide a protocol for powerful and reproducible measurement of survival time in Brachionus rotifers. Synchronization of culture conditions over several generations is of particular importance because maternal condition affects life history of offspring.

Rotifers are microscopic cosmopolitan zooplankton used as models in ecotoxicological and aging studies due to their several advantages such as short ...

A Murine Model of a Burn Wound Reconstructed with an Allogeneic Skin Graft

Trivial superficial wounds heal without complications by primary intention. Deep wounds, such as full thickness burns, heal by secondary intention and require surgical debridement and skin grafting. Successful integration of the donor graft into a recipient wound bed depends on timely recruitment of immune cells, robust angiogenic response and new extracellular matrix formation. The development of novel therapeutic agents, which target some key processes involved in wound healing, are hindered by the lack of reliable preclinical models with optimized objective assessment of wound closure. Here, we describe an inexpensive and reproducible model of experimental full thickness burn wound reconstructed with an allogeneic skin graft. The wound is induced on the dorsum surface of anaesthetized inbred wild type mice from the BALB/C and SKH1-Hrhr backgrounds. The burn is produced using a brass template measuring 10 mm in diameter, which is preheated to 80 &#176;C and delivered at a constant pressure for 20 s. Burn eschar is excised 24 hours after the injury and replaced with a full thickness graft harvested from the tail of a genetically similar donor mouse. No specialized equipment is required for the procedure and surgical techniques are straightforward to follow. The method may be effortlessly implemented and reproduced in most research settings. Certain limitations are associated with the model. Due to technical difficulties, the harvest of thinner split thickness skin grafts is not possible. The surgical method we describe here allows for the reconstruction of burn wounds using full thickness skin grafts. It may be used to carry out preclinical therapeutic testing.

The aim of this study was to develop a murine model of burn wound healing. A thermal burn was induced on the dorsal skin of mice using a preheated brass template. Burned tissue was debrided and overlaid with a skin graft harvested from the tail of a genetically similar donor mouse.

Trivial superficial wounds heal without complications by primary intention. Deep wounds, such as full thickness burns, heal by secondary intention and ...

Quantitative Proteomics Workflow using Multiple Reaction Monitoring Based Detection of Proteins from Human Brain Tissue

The proteomic analysis of the human brain tissue over the last decade has greatly enhanced our understanding of the brain. However, brain related disorders continue to be a major contributor of deaths around the world, necessitating the need for even greater understanding of their pathobiology. Traditional antibody-based techniques like western blotting or immunohistochemistry suffer from being low-throughput besides being labor-intensive and qualitative or semi-quantitative. Even conventional mass spectrometry-based shotgun approaches fail to provide conclusive evidence to support a certain hypothesis. Targeted proteomics approaches are largely hypothesis driven and differ from the conventional shotgun proteomics approaches that have been long in use. Multiple reaction monitoring is one such targeted approach that requires the use of a special mass spectrometer called the tandem quadrupole mass spectrometer or triple quadrupole mass spectrometer. In the current study, we have systematically highlighted the major steps involved in performing a successful tandem quadrupole mass spectrometry-based proteomics workflow using human brain tissue with an aim to introduce this workflow to a broader research community.

The protocol aims to introduce the use of a triple quadrupole mass spectrometer for Multiple Reaction Monitoring (MRM) of proteins from clinical samples. We have provided a systematic workflow starting from sample preparation to data analysis for clinical samples with all the necessary precautions to be taken.