This work was supported by grants #1K08HL088260 and #1R01HL133462-01A1 (NHLBI) (A.B.P., H.N., S.J.), and the Batchelor Foundation for Pediatric Research (D.M., H.N., S.J., A.A.H., A.B.P.). C57BL/6 and BALB/c mice used in this study were either bred in our facility or provided by Jackson Labs or Taconic.

All studies were conducted under rodent research protocols reviewed and approved by the Institutional Animal Care and Use Committee (IACUC) of the University of Miami Miller School of Medicine, which meets the veterinary standards set by the American Association for Laboratory Animal Science (AALAS).
1. Preparation of Solutions
<ol>
	<li>As described in Table 1, prepare the Colon Buffer, Silica-Based Density Separation Media 100%, Silica-Based Density Separation Media 66%, Silica-bas...

<ol>
	<li>Schneeman, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gastrointestinal+physiology+and+functions.">Gastrointestinal physiology and functions.</a> British Journal of Nutrition. 88, S159-S163 (2002).</li><li>Arranz, E., Pena, A. S., Bernardo, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mediators+of+inflammation+and+immune+responses+in+the+human+gastrointestinal+tract.">Mediators of inflammation and immune responses in the human gastrointestinal tract.</a> Mediators of inflammation. 2013, 1-3 (2013).</li><li>Blumberg, R. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inflammation+in+the+intestinal+tract:+pathogenesis+and+treatment.">Inflammation in the intestinal tract: pathogenesis and treatment.</a> Digestive diseases. 27 (4), 455-464 (2009).</li><li>Pabst, R., Russell, M. W., Brandtzaeg, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tissue+Distribution+of+Lymphocytes+and+Plasma+Cells+and+the+Role+of+the+Gut.">Tissue Distribution of Lymphocytes and Plasma Cells and the Role of the Gut.</a> Trends in Immunology. 29 (5), 206-208 (2008).</li><li>Reibig, S., Hackenbrunch, C., Hovelmeyer, N., Waisman, A., Becher, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+of+T+Cells+from+the+Gut.">Isolation of T Cells from the Gut.</a> T-Helper Cells: Methods and Protocols, Methods in Molecular Biology. , 21-25 (2014).</li><li>Mowat, A. M., Agace, W. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regional+Specialization+within+the+Intestinal+Immune+System.">Regional Specialization within the Intestinal Immune System.</a> Nature Reviews Immunology. 14 (10), 667-685 (2014).</li><li>Brandtzaeg, P., Kiyono, H., Pabst, R., Russell, M. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Terminology:+Nomenclature+of+mucosa-associated+lymphoid+tissue.">Terminology: Nomenclature of mucosa-associated lymphoid tissue.</a> Mucosal Immunology. 1 (1), 31-37 (2008).</li><li>Schieferdecker, H. L., Ullrich, R., Hirseland, H., Zeitz, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=T+cell+differentiation+antigens+on+lymphocytes+in+the+human+intestinal+lamina+propria.">T cell differentiation antigens on lymphocytes in the human intestinal lamina propria.</a> Journal of Immunology. 148 (8), 2816-2822 (1992).</li><li>Mowat, A. M., Viney, J. 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+anatomical+basis+of+intestinal+immunity.">The anatomical basis of intestinal immunity.</a> Immunological Reviews. 156, 145-166 (1997).</li><li>Ford, A. C., Lacy, B. E., Talley, N. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Irritable+Bowel+Syndrome.">Irritable Bowel Syndrome.</a> The New England Journal of Medicine. 376 (26), 2566-2578 (2017).</li><li>Harb, W. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Crohn's+Disease+of+the+Colon,+Rectum,+and+Anus.">Crohn's Disease of the Colon, Rectum, and Anus.</a> Surgical Clinics of North America. 95 (6), 1195-1210 (2015).</li><li>Ungaro, R., Mehandru, S., Allen, P. B., Pyrin-Biroulet, L., Colombel, J. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ulcerative+Colitis.">Ulcerative Colitis.</a> The Lancet. 389 (10080), 1756-1770 (2017).</li><li>Mohty, B., Mohty, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-term+complications+and+side+effects+after+allogeneic+hematopoietic+stem+cell+transplantation:+an+update.">Long-term complications and side effects after allogeneic hematopoietic stem cell transplantation: an update.</a> Blood cancer journal. 1 (4), 1-5 (2011).</li><li>Hatzimichael, E., Tuthill, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hematopoietic+stem+cell+transplantation.">Hematopoietic stem cell transplantation.</a> Stem cells and cloning: advances and applications. 3, 105-117 (2010).</li><li>Hernandez-Margo, P. M., 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=Colonic+Complications+Following+Human+Bone+Marrow+Transplantation.">Colonic Complications Following Human Bone Marrow Transplantation.</a> Journal of Coloproctology. 35 (1), 46-52 (2015).</li><li>Del Campo, L., Leon, N. G., Palacios, D. C., Lagana, C., Tagarro, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Abdominal+Complications+Following+Hematopoietic+Stem+Cell+Transplantation.">Abdominal Complications Following Hematopoietic Stem Cell Transplantation.</a> Radio Graphics. 34 (2), 396-412 (2014).</li><li>Lee, J., Lim, G., Im, S., Chung, N., Hahn, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gastrointestinal+Complications+Following+Hematopoietic+Stem+Cell+Transplantation+in+Children.">Gastrointestinal Complications Following Hematopoietic Stem Cell Transplantation in Children.</a> Korean Journal of Radiology. 9 (5), 449-457 (2008).</li><li>Takatsuka, H., Iwasaki, T., Okamoto, T., Kakishita, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intestinal+Graft-Versus-Host+Disease:+Mechanisms+and+Management.">Intestinal Graft-Versus-Host Disease: Mechanisms and Management.</a> Drugs. 63 (1), 1-15 (2003).</li><li>Shuyu, E., 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=Bidirectional+immune+tolerance+in+nonmyeloablative+MHC-mismatched+BMT+for+murine+&#946;-thalassemia.">Bidirectional immune tolerance in nonmyeloablative MHC-mismatched BMT for murine &#946;-thalassemia.</a> Blood. 129 (22), 3017-3030 (2017).</li><li>van der Merwe, M., 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=Recipient+myeloid-derived+immunomodulatory+cells+induce+PD-1+ligand-dependent+donor+CD4+Foxp3++regulatory+T+cell+proliferation+and+donor-recipient+immune+tolerance+after+murine+nonmyeloablative+bone+marrow+transplantation.">Recipient myeloid-derived immunomodulatory cells induce PD-1 ligand-dependent donor CD4+Foxp3+ regulatory T cell proliferation and donor-recipient immune tolerance after murine nonmyeloablative bone marrow transplantation.</a> Journal of Immunology. 191 (11), 5764-5776 (2013).</li><li>Couter, C. J., Surana, N. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+and+Flow+Cytometric+Characterization+of+Murine+Small+Intestinal+Lymphocytes.">Isolation and Flow Cytometric Characterization of Murine Small Intestinal Lymphocytes.</a> Journal of Visualized Experiments. (111), e54114 (2016).</li><li>Qiu, Z., Sheridan, B. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolating+Lymphocytes+from+the+Mouse+Small+Intestinal+Immune+System.">Isolating Lymphocytes from the Mouse Small Intestinal Immune System.</a> Journal of Visualized Experiments. (132), e57281 (2018).</li><li>Weigmann, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+and+subsequent+analysis+of+murine+lamina+propria+mononuclear+cells+from+colonic+tissue.">Isolation and subsequent analysis of murine lamina propria mononuclear cells from colonic tissue.</a> Nature Protocols. 2, 2307-2311 (2007).</li><li>Bull, D. M., Bookman, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+and+functional+characterization+of+human+intestinal+mucosal+lymphoid+cells.">Isolation and functional characterization of human intestinal mucosal lymphoid cells.</a> Journal of Clinical Investigation. 59 (5), 966-974 (1977).</li><li>Davies, M. D., Parrott, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+and+purification+of+lymphocytes+from+the+epithelium+and+lamina+propria+of+murine+small+intestine.">Preparation and purification of lymphocytes from the epithelium and lamina propria of murine small intestine.</a> Gut. 22, 481-488 (1981).</li><li>Carrasco, 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=Comparison+of+Lymphocyte+Isolation+Methods+for+Endoscopic+Biopsy+Specimens+from+the+Colonic+Mucosa.">Comparison of Lymphocyte Isolation Methods for Endoscopic Biopsy Specimens from the Colonic Mucosa.</a> Journal of Immunological Methods. 389 (1-2), 29-37 (2013).</li><li>Zhang, Y., Ran, L., Li, C., Chen, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diversity,+Structures,+and+Collagen-Degrading+Mechanisms+of+Bacterial+Collagenolytic+Proteases.">Diversity, Structures, and Collagen-Degrading Mechanisms of Bacterial Collagenolytic Proteases.</a> Applied and Environmental Microbiology. 81 (18), 6098-6107 (2015).</li><li>Harrington, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bacterial+collagenases+and+collagen-degrading+enzymes+and+their+potential+role+in+human+disease.">Bacterial collagenases and collagen-degrading enzymes and their potential role in human disease.</a> Infection and immunity. 64 (6), 1885-1891 (1996).</li><li>Duarte, A. S., Correia, A., Esteves, A. 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The authors declare no competing financial interests.

This visual protocol describes well-tolerated methods for the isolation of colonic mononuclear cells including lamina propria lymphocytes (LPL). Given that this protocol was optimized in evaluating severe post-transplant mouse colitis models where inflammatory cytokines and tissue injury lend themselves to poor viability of recovered MNC, we anticipate that these methods can be translated to other applications requiring phenotypic analysis of colonic MNC. These include but, are not limited to assessing colon inflammation...

Though the gastrointestinal (GI) tract is primarily dedicated to the processing and reabsorption of nutrients from food, the GI tract also maintains central roles in the integrity of the vascular, lymphatic, and nervous systems and of numerous other organs through its mucosal and submucosal immune system1. The GI immune system has an influential role in both gastrointestinal and systemic health due to its constant exposure to foreign antigens from food, commensal bacteria, or invading pathogens1,2. Thus, the GI immune system must maintain a delicate balance in which it tolerates non-pathogenic antigens while responding appropriately to pathogenic antigens1,2. When the balance of tolerance and defense is disrupted, localized or systemic immune dysregulation and inflammation can occur resulting in a myriad of diseases1,2,3.
The intestine harbors at least 70% of all lymphoid cells in the body4. Most primary immunologic interactions involve at least one of three immune stations in the intestine: 1) Peyer&#8217;s Patches, 2) Intraepithelial lymphocytes (IEL) and 3) lamina propria lymphocytes (LPL). Each of these is comprised of a complex interconnected network of immune cells that rapidly respond to normal immune challenges in the gut5. Restricted to the stroma above the muscularis mucosae, the loosely structured lamina propria is the connective tissue of the gut mucosa and includes scaffolding for the villus, the vasculature, lymphatic drainage, and mucosal nervous system, as well as many innate and adaptive immune subsets6,7,8,9. LPL are comprised of CD4+ and CD8+ T cells in an approximate ratio of 2:1, plasma cells and myeloid lineage cells including, dendritic cells, mast cells, eosinophils and macrophages6.
There is a growing interest in understanding the immune dysregulation and inflammation of the gut as it pertains to various disease states. Such conditions as Crohn&#8217;s disease and ulcerative colitis all manifest varying levels of colonic inflammation10,11,12. Additionally, patients with malignant or non-malignant disorders of the marrow or immune system who undergo an allogeneic bone marrow transplantation (allo-BMT) can develop various forms of colitis including 1) direct toxicity from conditioning regimens before BMT, 2) infections caused by immunosuppression after BMT and 3) graft-versus-host disease (GVHD) driven by donor-type T cells reacting to donor allo-antigens in the tissues after BMT13,14,15. All these post-BMT complications result in significant alterations in the immune milieu of the intestines16,17,18. The proposed method allows a dependable assessment of immune cell accumulation in the mouse colon and, when applied to murine recipients after BMT, facilitates an efficient assay of both donor and recipient immune cells involved in transplant tolerance19,20. Additional causes of gut inflammation include malignancies, food allergies, or disruption of the gut microbiome. This protocol allows access of gut mononuclear cells from the colon and, with modifications, to leukocytes of the small intestine in any of these preclinical murine models.
A PubMed search using the search terms &#8220;intestine AND immune cell AND isolation&#8221; reveals over 200 publications describing methods for small intestine digestion to extract immune cells. However, a similar literature search for colon yields no well-delineated protocols specifying isolation of immune cells from the colon. This may be because the colon has more muscular and interstitial layers, rendering it more difficult to completely digest than the small intestine. Unlike existing protocols, this protocol specifically uses Collagenase E from Clostridium histolyticum without other bacterial collagenases (Collagenase D/ Collagenase I). We demonstrate that, using this protocol, digestion of the colonic tissue can be achieved while preserving the quality of isolated gut mononuclear immune cells (MNC) without the addition of anti-clumping reagents such as sodium versenate (EDTA), Dispase II, and deoxyribonuclease I (DNAse I)21,22,23. This protocol is optimized to allow reproducible robust extraction of viable MNC from the murine colon for further directed studies and should lend itself to the study of immunology of the colon or (with modifications) the small intestine24,25.

<table>
	<tbody>
		<tr>
			<td>60 mm Petri DIsh</td>
			<td>Thermo Scientific</td>
			<td>150288</td>
			<td></td>
		</tr>
		<tr>
			<td>1x PBS</td>
			<td>Corning</td>
			<td>21-040-CV</td>
			<td></td>
		</tr>
		<tr>
			<td>10x PBS</td>
			<td>Lonza BioWhittaker</td>
			<td>BW17-517Q</td>
			<td></td>
		</tr>
		<tr>
			<td>10 mL Disposable Serological Pipette</td>
			<td>Corning</td>
			<td>4100</td>
			<td></td>
		</tr>
		<tr>
			<td>10mL Syringe</td>
			<td>Becton Dickinson</td>
			<td>302995</td>
			<td></td>
		</tr>
		<tr>
			<td>15mL Non-Sterile Conical Tubes</td>
			<td>TruLine</td>
			<td>TR2002</td>
			<td></td>
		</tr>
		<tr>
			<td>18- gauge Blunt Needle</td>
			<td>Becton Dickinson</td>
			<td>305180</td>
			<td></td>
		</tr>
		<tr>
			<td>25 mL Disposable Serological Pipette</td>
			<td>Corning</td>
			<td>4250</td>
			<td></td>
		</tr>
		<tr>
			<td>40 micrometer pore size Cell Strainer</td>
			<td>Corning</td>
			<td>352340</td>
			<td></td>
		</tr>
		<tr>
			<td>50 mL Falcon Tube</td>
			<td>Corning</td>
			<td>21008-951</td>
			<td></td>
		</tr>
		<tr>
			<td>Bovine Serum Albumin (BSA)</td>
			<td>Sigma</td>
			<td>A4503-1KG</td>
			<td></td>
		</tr>
		<tr>
			<td>Fixation Buffer</td>
			<td>Biolegend</td>
			<td>420801</td>
			<td></td>
		</tr>
		<tr>
			<td>E. coli Collagenase E from Clostridium histolyticum</td>
			<td>Sigma</td>
			<td>C2139</td>
			<td></td>
		</tr>
		<tr>
			<td>EDTA, 0.5M Sterile Solution</td>
			<td>Amresco</td>
			<td>E177-500ML</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum</td>
			<td>Thermo /Fisher Scientific -HyCLone</td>
			<td>SV30014.03</td>
			<td></td>
		</tr>
		<tr>
			<td>HEPES</td>
			<td>GE Healthcare-HyClone</td>
			<td>SH30237.01</td>
			<td></td>
		</tr>
		<tr>
			<td>Percoll</td>
			<td>GE Healthcare-Life Sciences</td>
			<td>1708901</td>
			<td></td>
		</tr>
		<tr>
			<td>RPMI Medium</td>
			<td>Corning</td>
			<td>17-105-CV</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium Azide</td>
			<td>VWR Life Science Amresco</td>
			<td>97064-646</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypan Blue</td>
			<td>Lonza BioWhittaker</td>
			<td>17-942E</td>
			<td></td>
		</tr>
	</tbody>
</table>

isolation of lamina propria mononuclear cells from murine colon using collagenase e

The intestine is the home to the largest number of immune cells in the body. The small and large intestinal immune systems police exposure to exogenous antigens and modulate responses to potent microbially derived immune stimuli. For this reason, the intestine is a major target site of immune dysregulation and inflammation in many diseases including but, not limited to inflammatory bowel diseases such as Crohn&#8217;s disease and ulcerative colitis, graft-versus-host disease (GVHD) after bone marrow transplantation (BMT), and many allergic and infectious conditions. Murine models of gastrointestinal inflammation and colitis are heavily used to study GI complications and to pre-clinically optimize strategies for prevention and treatment. Data gleaned from these models via isolation and phenotypic analysis of immune cells from the intestine is critical to further immune understanding that can be applied to ameliorate gastrointestinal and systemic inflammatory disorders. This report describes a highly effective protocol for the isolation of mononuclear cells (MNC) from the colon using a mixed silica-based density gradient interface. This method reproducibly isolates a significant number of viable leukocytes while minimizing contaminating debris, allowing subsequent immune phenotyping by flow cytometry or other methods.

When working with murine colon disease models, it is helpful to be able to both quantify and qualitatively assess, among the MNC of the colon, multiple immune cell subsets involved in the inflammatory process. The single-cell suspension of MNC obtained through the application of this protocol facilitates such phenotypic characterization in a robust and reproducible manner. As a proof of principle for the application of this isolation method under diverse experimental settings, we retrieve...

Watch this Scientific Journal Video about Isolation of Lamina Propria Mononuclear Cells from Murine Colon Using Collagenase E at JoVE.com

Isolation of Lamina Propria Mononuclear Cells from Murine Colon Using Collagenase E

The goal of this protocol is to isolate mononuclear cells that reside in the lamina propria of the colon by enzymatic digestion of the tissue using collagenase. This protocol allows for the efficient isolation of mononuclear cells resulting in a single cell suspension which in turn can be used for robust immunophenotyping.

The intestine is the home to the largest number of immune cells in the body. The small and large intestinal immune systems police exposure to exogenous ...

Isolation in phenotypic analysis of immune cells from the intestine using this protocol have proven applicable to the understanding of GI and systemic inflammatory disorders. This method isolates a significant number of viable mononuclear cells by minimizing contaminating debris allowing subsequent immune phenotyping by Fleur's Atomistry or other methods. As the intestine is a major target site of inflammation in many diseases, this protocol may be useful for the study of intestinal immune populations in mouse models of cancer, allergy, transplantation, and autoimmunity.To optimize the yield and efficiency of this protocol, it is recommended that key solutions and materials be prepared in advance as noted. After euthanizing the mouse and making a vertical midline incision, use fine dissection scissors to open the peritoneum. Using forceps, move the small bowel to one side and expose the descending colon.Pull upwards slightly on the descending colon to maximally expose the rectal portion of the colon. Then, cut the distal rectum deep in the pelvis and dissect the entire colon as one unit from the distal rectum to the cecal cap. First, place the colon on a moistened paper towel and use the blunt end of a pair of scissors or forceps to apply mild pressure to the bowel wall and extract the solid stool.Next, place the colon in a petri dish and use a 10 milliliter syringe with an 18-gauge blunt filled needle to flush the gut with 10 milliliters of chilled colon buffer. Place the colon in a petri dish filled with 5-10 milliliters of chilled colon buffer and agitate manually to wash the remaining colonic contents. Repeat this wash 2-3 times, using a new petri dish containing fresh buffer for each wash.After this, transfer the colon to a new petri dish containing fresh chilled colon buffer. Cut the colon longitudinally from its more muscular rectal end to the proximal colon, to generate a single rectangular open colon piece. Discard the median in the dish and replace it with clean chilled colon buffer.Place the rectangular colon tissue on a paper towel that is moistened with colon buffer and cut it by slicing it horizontally and then into small fragments. Use fine forceps to collect the colon fragments into a 50 milliliter polypropylene conical tube containing 20 milliliters of chilled colon buffer. Then, wash the fragments by vigorously swirling the tube for 30 seconds.After the wash, let the tissue fragments settle to the bottom of the tube before decanting or vacuum aspirating the supernatant, Making sure to avoid losing tissue fragments, repeat this entire wash process 3 times using fresh colon buffer for each wash. To begin, add 20 milliliters of collagenase digestion buffer to the tube containing the washed colon fragments. Seal the tube and place it in an orbital shaker at 37 degrees Celsius with a rotation rate of 2 times G for 60 minutes.Ensure the tissue fragments are in constant motion during agitation. First, pour 5 milliliters of 66%silica based density separation media into each of 3 separate 15 milliliter polypropylene tubes. Next, use a 25 milliliter serological pipette to collect only the supernatant from Collagenase Digestion 1.Filter the supernatant through a 40 microliter poor filtration fabric cell strainer placed into a clean 50 milliliter polypropylene conical tube. Fill the tube completely with chilled colon buffer to quench the collagenase digestion buffer. Then spin the cells, aspirate the supernatant, and keep the pellet on ice.Continue to perform Collagenase Digestion 2 as outlined in the text protocol. After Collagenase Digestion 2 is completed, flush the tissue fragments vigorously back and forth between the tube and a 10 milliliter syringe through an 18-gauge blunt end needle. Repeat this flush for at least 7-8 passages, continuing until no gross tissue fragments or debri are visible.Next, pass the tissue disaggregation suspension through a 40 micrometer poor filtration fabric cell strainer placed into a clean 50 milliliter polypropylene tube. Fill the tube to the rim with chilled colon buffer to quench the digestion and centrifuge at 800 times G in at 4 degrees Celsius for 5 minutes. Discard the supernatant via vacuum aspiration and pull the re suspended pellet from Collagenase Digestion 1 to its corresponding tube.After this, re suspend each pellet in 24 milliliters of 44%silica based density separation media per colon. Use a 10 milliliter serological pipette to slowly layer 8 milliliters of this media onto each of 3 tubes containing 66%silica based density separation media. Carefully balance the tubes within centrifuge buckets using a weigh scale or a balance.Centrifuge at 859 times G in at 20 degrees Celsius for 20 minutes without the break. Allow the roders to come to complete rest before removing tubes, taking care not to disrupt the cells at the gradient interface. First, visualize the gradient interface near the 5 milliliter mark, where typically a 1-2 milliliter thick white band is present.Vacuum aspirate and discard the top 7 milliliters of the gradient to allow easier pipette access to the interface. Using continuous manual suction and steady rotating wrist motion, collect the interface layer of cells. Collect until the interface between the two gradients is clear and refractile and transfer the interface to a new 50 milliliter polypropylene conical tube.Next, add FACS Buffer to this tub until the total suspension reaches 50 milliliters. Centrifuge at 800 times G in at 4 degrees Celsius for 5 minutes. Then, aspirate the supernatant via vacuum aspiration and re suspend the pellet in 1 milliliter of FACS Buffer.The procedure described in this video can be used to isolate mononuclear cells from the colon or, with modifications, from the small intestine. Plus, cytometry and data analysis is performed to compare the fractions of apoptotic and necrotic/dead lymphocytes when using either Collagenase E or D for the isolation, with our without DNAse 1 treatment. Following Annexin 5 and fixable live dead blue dye staining on single cell suspensions following each isolation, Collagenase E without DNAse showed a significantly higher percentage of live cells after isolation when compared to Collagenase D without DNAse.Even when compared to either collagenase with DNAse. In addition, we identified necrotic cells at a median percentage of 41.0%in the Collagenase E group versus 90.0%in the Collagenase D group. 75.9%in the Collagenase E DNAse group and 80.3%in the Collagenase D DNAse group.Multi perimetric flow cytometry is then applied to MNC isolated from CD45.2 valve-C recipient mice on Day 7 after receiving BMT or either allogeneic or syngeneic BMT models. The mean absolute numbers of Donor CD4 positive and CD8 positive T-cells extracted from the BMT recipient's colon are calculated and compared. So it can be important to identify and/or quantitate rare immune cell populations in such mouse models.Rare subsets, including donor derived FOX-P3 positive T regulatory cells are assessed in both syngeneic and allogeneic BMT models. Using this method, even rare subsets, such as donor derived colonic T regulatory infiltrating recipient mouse colon, after BMT, can be analyzed. It should be noted that Collagenase E is active at 37 degrees Celsius.So all collagenase solutions should be pre-warmed for adequate collagenase activity and thoroughly quenched to terminate activity. This protocol allows for a large number of mononuclear cells that can be used for subsequent characterization by a Fleur cytometry, molecular biology techniques, microscopy, culture, and site of, among others. This protocol provided a dependable assessment of inflammation in the colon of experimental versus controlled mice in a bone marrow transplant model.Thus facilitating the discovery of novel regulatory immune mechanisms of transplant tolerance. Collagenase from Clostridium Istoliticum is a reagent that should be handled with lab safety techniques. It poses a health hazard when inhaled and may cause skin and eye irritation.

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Research

JoVE Journal

Immunology and Infection

15.4K vistas.  University of Miami Miller School of Medicine. El aislamiento en el análisis fenotípico de las células inmunitarias del intestino utilizando este protocolo ha demostrado ser aplicable a la comprensión de los trastornos inflamatorios sistémicos y gastrointestinales. Este método aísla un número significativo de células mononucleares viables al minimizar los desechos contaminantes permitiendo el posterior fenotipado inmune por la Atomistry de Fleur u otros métodos. Como el intestino es un sitio objetivo principal de inflamación en...