Name: unraveling key players of humoral immunity: advanced and optimized lymphocyte isolation protocol from murine peyer's patches
Uploaded: 2018-11-21T14:00:00
Description: Watch this Scientific Journal Video about Unraveling Key Players of Humoral Immunity: Advanced and Optimized Lymphocyte Isolation Protocol from Murine Peyer's Patches at JoVE.com

We would like to thank Laura Strauss and Peter Sage for helpful discussions and support with flow cytometry analyses.

All studies and experiments described in this protocol were conducted under guidelines according to Institutional Animal Care and Use Committee (IACUC) of Beth Israel Deaconess Medical Center.
1. Designing Experimental Set-up and Mouse Groups
<ol>
	<li>(Optional) Co-house the experimental mice to facilitate horizontal transmission of gut microbiota between experimental mice and to reduce non-specific variability within PP lymphocytes. Additionally, use littermate controls of the same gender ...

<ol>
	<li>van den Berg, T. K., van der Schoot, C. E. <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+&#8216;self&#8217;+recognition:+a+role+for+CD47-SIRP&#945;+interactions+in+hematopoietic+stem+cell+transplantation.">Innate immune &#8216;self&#8217; recognition: a role for CD47-SIRP&#945; interactions in hematopoietic stem cell transplantation.</a> Trends in Immunology. 29 (5), 203-206 (2008).</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>Reboldi, A., Cyster, J. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Peyer&#8217;s+patches:+Organizing+B-cell+responses+at+the+intestinal+frontier.">Peyer&#8217;s patches: Organizing B-cell responses at the intestinal frontier.</a> Immunological Reviews. 271 (1), 230-245 (2016).</li><li>Heel, K. A., McCauley, R. D., Papadimitriou, J. M., Hall, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Review:+Peyer&#8217;s+patches.">Review: Peyer&#8217;s patches.</a> Journal of Gastroenterology and Hepatology. 12 (2), 122-136 (1997).</li><li>Fagarasan, S., Kinoshita, K., Muramatsu, M., Ikuta, K., Honjo, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+class+switching+and+differentiation+to+IgA-producing+cells+in+the+gut+lamina+propria.">In situ class switching and differentiation to IgA-producing cells in the gut lamina propria.</a> Nature. 413 (6856), 639-643 (2001).</li><li>Hopkins, S. A., Niedergang, F., Corthesy-Theulaz, I. E., Kraehenbuhl, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+recombinant+Salmonella+typhimurium+vaccine+strain+is+taken+up+and+survives+within+murine+Peyer&#8217;s+patch+dendritic+cells.">A recombinant Salmonella typhimurium vaccine strain is taken up and survives within murine Peyer&#8217;s patch dendritic cells.</a> Cellular Microbiology. 2 (1), 59-68 (2000).</li><li>Shreedhar, V. K., Kelsall, B. L., Neutra, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cholera+toxin+induces+migration+of+dendritic+cells+from+the+subepithelial+dome+region+to+T-+and+B-cell+areas+of+Peyer's+patches.">Cholera toxin induces migration of dendritic cells from the subepithelial dome region to T- and B-cell areas of Peyer's patches.</a> Infection and Immunity. 71 (1), 504-509 (2003).</li><li>Sato, A., Iwasaki, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Peyer&#8217;s+patch+dendritic+cells+as+regulators+of+mucosal+adaptive+immunity.">Peyer&#8217;s patch dendritic cells as regulators of mucosal adaptive immunity.</a> Cellular and Molecular Life Sciences. 62 (12), 1333-1338 (2005).</li><li>Bemark, M., Boysen, P., Lycke, N. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Induction+of+gut+IgA+production+through+T+cell-dependent+and+T+cell-independent+pathways.">Induction of gut IgA production through T cell-dependent and T cell-independent pathways.</a> Annals of the New York Academy of Sciences. 1247 (1), 97-116 (2012).</li><li>Fagarasan, S., Kawamoto, S., Kanagawa, O., Suzuki, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adaptive+Immune+Regulation+in+the+Gut:+T+Cell-Dependent+and+T+Cell-Independent+IgA+Synthesis.">Adaptive Immune Regulation in the Gut: T Cell-Dependent and T Cell-Independent IgA Synthesis.</a> Annual Review of Immunology. 28, 243-273 (2010).</li><li>Hase, K., 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=Uptake+through+glycoprotein+2+of+FimH+++bacteria+by+M+cells+initiates+mucosal+immune+response.">Uptake through glycoprotein 2 of FimH + bacteria by M cells initiates mucosal immune response.</a> Nature. 462 (7270), 226-230 (2009).</li><li>Wu, 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=An+Inhibitory+Role+for+the+Transcription+Factor+Stat3+in+Controlling+IL-4+and+Bcl6+Expression+in+Follicular+Helper+T+Cells.">An Inhibitory Role for the Transcription Factor Stat3 in Controlling IL-4 and Bcl6 Expression in Follicular Helper T Cells.</a> Journal of Immunology. 195 (5), 2080-2089 (2015).</li><li>Vinuesa, C. G., Tangye, S. G., Moser, B., Mackay, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Follicular+B+helper+T+cells+in+antibody+responses+and+autoimmunity.">Follicular B helper T cells in antibody responses and autoimmunity.</a> Nature Reviews Immunology. 5 (11), 853-865 (2005).</li><li>Victora, G. D., Nussenzweig, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Germinal+Centers.">Germinal Centers.</a> Annual Review of Immunology. 30, 429-457 (2012).</li><li>Vaeth, 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=Store-Operated+Ca2+Entry+in+Follicular+T+Cells+Controls+Humoral+Immune+Responses+and+Autoimmunity.">Store-Operated Ca2+Entry in Follicular T Cells Controls Humoral Immune Responses and Autoimmunity.</a> Immunity. 44 (6), 1350-1364 (2016).</li><li>Meli, A. 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=The+Integrin+LFA-1+Controls+T+Follicular+Helper+Cell+Generation+and+Maintenance.">The Integrin LFA-1 Controls T Follicular Helper Cell Generation and Maintenance.</a> Immunity. 45 (4), 831-846 (2016).</li><li>Fu, 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=Deficiency+in+T+follicular+regulatory+cells+promotes+autoimmunity.">Deficiency in T follicular regulatory cells promotes autoimmunity.</a> Journal of Experimental Medicine. 215 (3), 815-825 (2018).</li><li>Esp&#233;li, M., Walker, 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=.">.</a> T follicular helper cells - Methods and Protocols. , (2015).</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 Visual Experiments. (111), e54114 (2016).</li><li>De Jesus, M., Ahlawat, S., Mantis, 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=Isolating+And+Immunostaining+Lymphocytes+and+Dendritic+Cells+from+Murine+Peyer&#8217;s+Patches.">Isolating And Immunostaining Lymphocytes and Dendritic Cells from Murine Peyer&#8217;s Patches.</a> Journal of Visual Experiments. (73), e50167 (2013).</li><li>Pastori, C., Lopalco, L. <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+in+vitro+Activation+of+Mouse+Peyer&#8217;s+Patch+Cells+from+Small+Intestine+Tissue.">Isolation and in vitro Activation of Mouse Peyer&#8217;s Patch Cells from Small Intestine Tissue.</a> Bio-protocol. 4 (21), e1282 (2014).</li><li>Fukuda, S., Hase, K., Ohno, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Application+of+a+Mouse+Ligated+Peyer&#8217;s+Patch+Intestinal+Loop+Assay+to+Evaluate+Bacterial+Uptake+by+M+cells.">Application of a Mouse Ligated Peyer&#8217;s Patch Intestinal Loop Assay to Evaluate Bacterial Uptake by M cells.</a> Journal of Visual Experiments. (58), 3225 (2011).</li><li>Naito, Y., 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=Germinal+Center+Marker+GL7+Probes+Activation-Dependent+Repression+of+N-Glycolylneuraminic+Acid,+a+Sialic+Acid+Species+Involved+in+the+Negative+Modulation+of+B-Cell+Activation.">Germinal Center Marker GL7 Probes Activation-Dependent Repression of N-Glycolylneuraminic Acid, a Sialic Acid Species Involved in the Negative Modulation of B-Cell Activation.</a> Molecular and Cellular Biology. 27 (8), 3008-3022 (2007).</li><li>Bollig, N., 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=Transcription+factor+{IRF4}+determines+germinal+center+formation+through+follicular+T-helper+cell+differentiation.">Transcription factor {IRF4} determines germinal center formation through follicular T-helper cell differentiation.</a> Proceedings of the National Academy of Science of U. S. A. 109 (22), 8664-8669 (2012).</li><li>P&#233;rez-Mazliah, D., 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=Follicular+Helper+T+Cells+are+Essential+for+the+Elimination+of+Plasmodium+Infection.">Follicular Helper T Cells are Essential for the Elimination of Plasmodium Infection.</a> EBioMedicine. 24, 216-230 (2017).</li><li>Sage, P. T., Sharpe, A. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=T+follicular+regulatory+cells+in+the+regulation+of+B+cell+responses.">T follicular regulatory cells in the regulation of B cell responses.</a> Trends Immunology. 36 (7), 410-418 (2015).</li><li>Van Damme, N., 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=Chemical+agents+and+enzymes+used+for+the+extraction+of+gut+lymphocytes+influence+flow+cytometric+detection+of+T+cell+surface+markers.">Chemical agents and enzymes used for the extraction of gut lymphocytes influence flow cytometric detection of T cell surface markers.</a> Journal of Immunological Methods. 236 (1-2), 27-35 (2000).</li><li>Meenan, 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=Altered+expression+of+alpha+4+beta+7,+a+gut+homing+integrin,+by+circulating+and+mucosal+T+cells+in+colonic+mucosal+inflammation.">Altered expression of alpha 4 beta 7, a gut homing integrin, by circulating and mucosal T cells in colonic mucosal inflammation.</a> Gut. 40 (2), 241-246 (1997).</li><li>Cao, A. T., 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=Interleukin+(IL)+-21+promotes+intestinal+IgA+response+to+microbiota.">Interleukin (IL) -21 promotes intestinal IgA response to microbiota.</a> Mucosal Immunology. 8 (5), 1072-1082 (2015).</li><li>Wei, 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=Autophagy+enforces+functional+integrity+of+regulatory+T+cells+by+coupling+environmental+cues+and+metabolic+homeostasis.">Autophagy enforces functional integrity of regulatory T cells by coupling environmental cues and metabolic homeostasis.</a> Nature Immunology. 17 (3), 277-285 (2016).</li><li>Autengruber, A., Gereke, M., Hansen, G., Hennig, C., Bruder, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impact+of+enzymatic+tissue+disintegration+on+the+level+of+surface+molecule+expression+and+immune+cell+function.">Impact of enzymatic tissue disintegration on the level of surface molecule expression and immune cell function.</a> European Journal of Microbiology &amp; Immunology. 2 (2), 112-120 (2012).</li><li>Trapecar, 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=An+Optimized+and+Validated+Method+for+Isolation+and+Characterization+of+Lymphocytes+from+HIV++Human+Gut+Biopsies.">An Optimized and Validated Method for Isolation and Characterization of Lymphocytes from HIV+ Human Gut Biopsies.</a> AIDS Research and Human Retroviruses. 33 (S1), (2017).</li><li>Bergqvist, P., Gardby, E., Stensson, A., Bemark, M., Lycke, N. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gut+IgA+Class+Switch+Recombination+in+the+Absence+of+CD40+Does+Not+Occur+in+the+Lamina+Propria+and+Is+Independent+of+Germinal+Centers.">Gut IgA Class Switch Recombination in the Absence of CD40 Does Not Occur in the Lamina Propria and Is Independent of Germinal Centers.</a> Journal of Immunology. 177 (11), 7772-7783 (2006).</li><li>Keil, B., Gilles, A. M., Lecroisey, A., Hurion, N., Tong, N. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Specificity+of+collagenase+from+Achromobacter+iophagus.">Specificity of collagenase from Achromobacter iophagus.</a> FEBS Letters. 56 (2), 292-296 (1975).</li><li>Mora, J. R., 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+imprinting+of+gut-homing+T+cells+by+Peyer&#8217;s+patch+dendritic+cells.">Selective imprinting of gut-homing T cells by Peyer&#8217;s patch dendritic cells.</a> Nature. 424 (6944), 88-93 (2003).</li><li>Reboldi, 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=Mucosal+immunology:+IgA+production+requires+B+cell+interaction+with+subepithelial+dendritic+cells+in+Peyer&#8217;s+patches.">Mucosal immunology: IgA production requires B cell interaction with subepithelial dendritic cells in Peyer&#8217;s patches.</a> Science. 352 (6287), (2016).</li></ol>

Here, we describe a protocol optimized for flow cytometric characterization of TFH and GC B cells. One of the major advantages of our protocol is that it enables the isolation of up to 107 (average 4&#8211;5 x 106 cells) total PP cells from a single mouse (C57BL/6 strain) without any digestive process. We observed that the total cell yield was positively correlated with the number of PPs and could be estimated from the following simple equation which is helpful for experimental planning: &#34;total ...

The entire gastrointestinal tract from the beginning to the end is decked with an extensive lymphoid network that contains immune cells more than any other organ in human and mouse1. Peyer&#39;s patches (PPs) constitute a major component of the intestinal branch of this cellular immune organization, so-called gut-associated lymphoid tissue (GALT)2,3. Within PPs, thousands of millions of antigens derived from dietary materials, commensal microbiota and pathogens are being sampled continuously, and when necessary appropriate immune responses toward them are mounted thus maintaining intestinal immune homeostasis. In that sense, PPs could be named as &#34;tonsils of the small intestine&#34;. PPs consist of major sub-compartments: subepithelial dome (SED), large B-cell follicle zones; the overlying follicle-associated epithelium (FAE) and interfollicular region (IFR) where T cells are located4. This unique compartmentalization of PPs enables different effector cell subsets to cooperate, thus, confers immunocompetence in the gut.
PPs lack afferent lymphatics, and due to this reason, antigens transported to PPs from small intestine are not being conducted through lymphatic vessels in contrast to most of the other lymphoid organs. Instead, specialized epithelial cells located in FAE, so-called M cells, are responsible for the transfer of luminal antigens into the PPs5. Subsequently, the transported antigens are picked up by the dendritic cells (DCs) and phagocytes that are located in the subepithelial dome (SED) region beneath the FAE6,7. This antigen sorting process by DCs in the PP is crucial to initiate adaptive immune response8 and subsequent generation of IgA secreting cells9.
Due to the heavy antigenic burden from commensal flora and dietary material, PPs host endogenously activated effector T and B cell subsets in great abundances such as TFH and IgA+ GC B cells10, suggesting that PPs represent a site of active immune response11. Detection of up to 20&#8211;25% TFH cells within total CD4+ T cell compartment and up to 10&#8211;15% GC B cells within total B cells is possible in PPs collected from unimmunized young C57BL/6 mice12. In contrast to other T helper cell types (i.e., Th1, Th2, Th17 cells), TFH cells show unique tropism into B cell follicles primarily owing to CXCR5 expression, which promotes TFH cell homing along CXCL13 gradient13. In the B cell follicle zones of PPs, TFH cells induce IgA class switch recombination and somatic hypermutation in activated B cells from which high-affinity IgA producing cells differentiate14. Subsequently, these antibody-secreting plasma cells migrate to the lamina propria (LP) and regulate immune homeostasis in the gut10.
Identification and characterization of TFH and GC B cell populations within PPs might enable researchers to investigate the dynamics of humoral immune responses under steady-state conditions without the need of time-consuming immunization models traditionally used in TFH-GC B cell studies15,16,17,18. Analyzing TFH cells within PPs is not as straightforward as other cell subsets. Technical challenges include identifying ideal tissue preparation conditions, surface antibody-marker combination, as well as selecting appropriate positive and negative controls. Both TFH and PP research fields exhibit great variability in terms of experimental procedures and are far from conferring a consensus to establish standardized protocols due to several reasons. First, each cell subset within PPs tends to be affected differentially by tissue preparation conditions requiring further modifications in a cell subset-specific manner. Second, there is a significant discrepancy among the reported methods regarding the details of cell preparation from PPs. Third, the number of protocol-based comparative studies investigating ideal tissue preparation techniques and experimental conditions for PP and TFH research is rather limited.
Current protocol-based studies suggested for PP cell preparation19,20,21,22 were not TFH- or GC B cell-oriented. Moreover, some tissue preparation conditions recommended for PPs19,20 such as collagenase-based digestion were found to affect the outcome of TFH identification by flow cytometry negatively18. On this basis, we reasoned that an optimized, standardized and reproducible protocol that can be used to study TFH and GC B cell dynamics within PPs would be valuable to investigators working on this topic. This need gave us the impetus to generate an improved and up-to-date protocol for the isolation and characterization of PP lymphocytes that is finely optimized for cellular recovery, viability, and efficiency for flow cytometric characterization of several T and B cell subsets. We also aimed to exclude several laborious preparation steps suggested in previous protocols, thereby, reducing the required manipulations and time for tissue and cell preparation from PPs.

<table>
	<tbody>
		<tr>
			<td>anti-mouse CD4 antibody</td>
			<td>eBioscience, Biolegend*</td>
			<td>17-0041-81 ,10054*</td>
			<td>For detailed information see Table 1</td>
		</tr>
		<tr>
			<td>anti-mouse CD19 antibody</td>
			<td>eBioscience</td>
			<td>MA5-16536</td>
			<td>For detailed information see Table 1</td>
		</tr>
		<tr>
			<td>anti-mouse PD-1 antibody</td>
			<td>eBioscience</td>
			<td>61-9985-82</td>
			<td>For detailed information see Table 1</td>
		</tr>
		<tr>
			<td>anti-mouse ICOS antibody</td>
			<td>eBioscience</td>
			<td>12-9942-82</td>
			<td>For detailed information see Table 1</td>
		</tr>
		<tr>
			<td>anti-mouse GL7 antibody</td>
			<td>Biolegend</td>
			<td>144610</td>
			<td>For detailed information see Table 1</td>
		</tr>
		<tr>
			<td>anti-mouse CXCR5 antibody</td>
			<td>Biolegend*, BD Bioscience</td>
			<td>145512*, 551960</td>
			<td>For detailed information see Table 1</td>
		</tr>
		<tr>
			<td>anti-mouse BCL-6 antibody</td>
			<td>Biolegend</td>
			<td>358512</td>
			<td>For detailed information see Table 1</td>
		</tr>
		<tr>
			<td>anti-mouse Foxp3 antibody</td>
			<td>eBioscience</td>
			<td>17-5773-82</td>
			<td>For detailed information see Table 1</td>
		</tr>
		<tr>
			<td>Streptavidin-BV421</td>
			<td>BD Bioscience</td>
			<td>563259</td>
			<td>For detailed information see Table 1</td>
		</tr>
		<tr>
			<td>FixableViability Dye</td>
			<td>eBioscience</td>
			<td>L34957</td>
			<td>For detailed information see Table 1</td>
		</tr>
		<tr>
			<td>7AAD</td>
			<td>Biolegend</td>
			<td>420404</td>
			<td>For detailed information see Table 1</td>
		</tr>
		<tr>
			<td>FcBlock (CD16/32)</td>
			<td>BD Bioscience</td>
			<td>553141</td>
			<td>For detailed information see Table 1</td>
		</tr>
		<tr>
			<td>Collagenase II</td>
			<td>Worthington</td>
			<td>LS004176</td>
			<td></td>
		</tr>
		<tr>
			<td>Collagenase IV</td>
			<td>Worthington</td>
			<td>LS004188</td>
			<td></td>
		</tr>
		<tr>
			<td>Foxp3/Transcription Factor Staining Buffer Set</td>
			<td>eBioscience</td>
			<td>00-5523-00</td>
			<td></td>
		</tr>
		<tr>
			<td>6-well,12-well &#38; 96-well plates</td>
			<td>Falcon/Corning</td>
			<td>353046,353043/3596</td>
			<td></td>
		</tr>
		<tr>
			<td>50 ml conical tubes</td>
			<td>Falcon</td>
			<td>3520</td>
			<td></td>
		</tr>
		<tr>
			<td>40 &#181;m cell strainer</td>
			<td>Falcon</td>
			<td>352340</td>
			<td></td>
		</tr>
		<tr>
			<td>10 ml syringe-plunger</td>
			<td>Exel INT</td>
			<td>26265</td>
			<td></td>
		</tr>
		<tr>
			<td>RPMI</td>
			<td>Corning</td>
			<td>15-040-CV</td>
			<td></td>
		</tr>
		<tr>
			<td>PBS</td>
			<td>Corning</td>
			<td>21-040-CM</td>
			<td></td>
		</tr>
		<tr>
			<td>FBS</td>
			<td>Atlanta Biologicals</td>
			<td>S11150</td>
			<td></td>
		</tr>
		<tr>
			<td>Orbital shaker</td>
			<td>VWR</td>
			<td>Model 200</td>
			<td></td>
		</tr>
		<tr>
			<td>Curved-end scissor</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Fine Serrated Forceps</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Small curved scissor</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

unraveling key players of humoral immunity: advanced and optimized lymphocyte isolation protocol from murine peyer's patches

In the gut mucosa, immune cells constitute a unique immunological entity, which promotes immune tolerance while concurrently conferring immune defense against pathogens. It is well established that Peyer&#39;s patches (PPs) have an essential role in the mucosal immune network by hosting several effector T and B cell subsets. A certain fraction of these effector cells, follicular T helper (TFH) and germinal center (GC) B cells are professionalized in the regulation of humoral immunity. Hence, the characterization of these cell subsets within PPs in terms of their differentiation program and functional properties can provide important information about mucosal immunity. To this end, an easily applicable, efficient and reproducible method of lymphocyte isolation from PPs would be valuable to researchers. In this study, we aimed to generate an effective method to isolate lymphocytes from mouse PPs with high cell yield. Our approach revealed that initial tissue processing such as the use of digestive reagents and tissue agitation, as well as cell staining conditions and selection of antibody panels, have great influence on the quality and identity of the isolated lymphocytes and on experimental outcomes.
Here, we describe a protocol enabling researchers to efficiently isolate lymphocyte populations from PPs allowing reproducible flow cytometry-based assessment of T and B cell subsets primarily focusing on&#160;TFH and GC B cell subsets.

In contrast to a previous protocol20, we have observed that PPs are not evenly distributed throughout the SI but are localized more densely towards the distal and proximal ends of the SI as shown in Figure 1A. Flow cytometric analysis showed that, if followed correctly, our protocol gives a PP lymphocyte population that demonstrates forward-side scatter distribution similar to splenocytes (<strong clas...

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Unraveling Key Players of Humoral Immunity: Advanced and Optimized Lymphocyte Isolation Protocol from Murine Peyer's Patches

In this study, we present a novel and effective protocol for the isolation of lymphocytes from Peyer&#39;s Patches (PPs), which can be subsequently used for in vivo and in vitro functional assays as well as flow cytometric studies of follicular T helper and germinal center B cells.

In the gut mucosa, immune cells constitute a unique immunological entity, which promotes immune tolerance while concurrently conferring immune defense ...

This method can answer key questions about the phenotype of mouse Peyer's Patch isolated T and B cell subsets. In particular, follicular T helper and germinal center B cell populations. The main advantage of this technique is that it dispenses with several laborous preparation steps such as collagenase based digestion that compromise the quality and identity of the isolated lymphocytes.Begin by placing a mouse in the supine position and sterilizing the abdomen with 70%ethanol. Make a midline abdominal incision through the skin and peritoneum from the pubis to the rib cage to open the peritineal cavity and locate the cecum and the ileocecal junction. Make as distal as possible cut at the junction to separate the small intestine from the cecum.Cut the mesentery with scissors to carefully remove the entire small intestine up to the pyloric sphincter. Snip the junction between the pylorus and the duodenum to completely detach the small intestine from the abdominal cavity and place the isolated small intestine into one well of a 6-well plate containing cold RPMI medium supplemented with 10%fetal bovine serum, or FBS, on ice. Then, gently agitate the tissues manually until all of the segments are submerged in the cold medium.When all of the intestines have been harvested, use forceps to grasp the mesenteric fat of one edge of the intestine and place the sample, mesenteric side down, on a paper towel. Moisten the entire intestinal segment with RPMI 10%FBS to avoid tissue dehydration and stickiness and locate the Peyer's patches, which appear as white multilobulated aggregates with a cauliflower-like shape on the anti-mesenteric side of the intestinal wall. To harvest the Peyer's patches, use curved surgical scissors with the curve facing up to gently excise each patch from it's distal and proximal borders, taking care to exclude the surrounding intestinal tissue, and place the Peyer's patches into individual wells of a 12-well plate containing ice-cold RPMI 10%FBS on ice as they are collected.When all of the patches have been acquired, use scissors to cut the tip of a 1 millimeter micro pipette tip so that the diameter is large enough to aspirate individual Peyer's patches and transfer the Peyer's patches into 150 millimeter conical tubes per mouse containing 25 milliliters of 37 degrees Celsius RPMI 10%FBS. Then place the tube in an orbital shaker at 37 degrees Celsius with continuous agitation at 125-150 RPM for 10 minutes. At the end of the agitation, transfer the Peyer's patches onto 140 micrometer cell strainer per mouse, and use the rubber end of one 10 milliliter syringe plunger per animal to gently disrupt the Peyer's patches through the mesh into individual 50 milliliter conical tubes.Rinse the strainers with 15-20 milliliters of cold RPMI 10%FBS and collect the cells by centrifugation. After carefully discarding the supernatant, resuspend the cells at an approximately 1 times 10 to the 7th cells per milliliter of RPMI 10%FBS concentration for counting. Then transfer 2-2.5 times 10 to the 6th cells per 200 microliters of medium to each well of a 96-well round bottom plate and pellet the cells by centrifugation.After discarding the supernatant with gentle flicking, centrifuge wash the cells in 200 microliters of standing buffer. Label the cells in 100 microliters of fixable viability dye, diluted in protein-free buffer for 30 minutes at 4 degrees Celsius, protected from light, followed by 2 washes and fresh staining buffer. After discarding the supernatant, resuspend the pellets in 20 microliters of FC block for 15 minute incubation at 4 degrees Celsius, followed by the addition of 80 microliters of primary surface antibody cocktail of interest, for 30 minutes on ice, protected from light.At the end of the surface antibody incubation, centrifuge wash the cells two times in an excess volume of staining buffer, and resuspend the pellets in 100 microliters of secondary surface staining solution, supplemented with streptavidin. After 15 minutes on ice protected from light, centrifuge wash the cells 2 times in fresh staining buffer and resuspend the pellets in 200 microliters of fixation, permeablization working solution for a no more than 20 minute incubation on ice, protected from light. At the end of the incubation, centrifuge the plate immediately, followed by a centrifuge was in 200 microliters of permeablization buffer per well.Next, resuspend the cells in 20 microliters of FC block, diluted in permeablization buffer as demonstrated, followed by the addition of 80 microliters of the intracellular antibody cocktail of interest, for 30 minutes at room temperature, protected from light. Wash the cells with 100 microliters of permeablization buffer, followed by a second wash in 200 microliters of permeablization buffer. Then, resuspend the pellets in 200 microliters of staining buffer, and transfer the cells to the appropriate corresponding 5 milliliter flow cytometric analysis tubes, in a final volume of 400 microliters of staining buffer per tube.Peyer's patches are not evenly distributed throughout the small intestine, but are localized more densely towards the distal and proximal ends of the tissue. This protocol facilitates the isolation of a Peyer's patch lymphocyte population that demonstrates a forward-side scattered distribution, similar to that observed for splenocytes, with a greater than 95%cell viability. CD4 CD19 Double Positive cells constitute about 1%of the total Peyer's patch lymphocyte population.These express high levels of CXCR5 and GL7, which, when not excluded, can lead to false positive results in the gating of T-helper follicular and germinal center B cell, respectively. Compared to other secondary lymphoid organs, Peyer's patches exhibit a significantly higher ratio of germinal center B cells, at a range of 2-10%of the total B cell population under steady state conditions. Like germinal center B cells, the follicular T-helper cell fraction also varies in individual unimmunized mice, with a range of 10-20%of total, the CD4 Positive Peyer's patch T-lymphocyte population.Collagenase based enzymatic digestion leads to massive reduction of CXCR5 T-helper follicular cell expression, while leaving the expression of other surface molecules unaffected. After this development, this technique paved the way for the identification of key cellular factors within the Peyer's patches that are involved in mucosal and humeral immunity.

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Research

JoVE Journal

Cancer Research

A Detailed Protocol for Characterizing the Murine C1498 Cell Line and its Associated Leukemia Mouse Model

The intravenous injection of C1498 cells into syngeneic or congenic mice has been performed since 1941. These injections result in the development of acute leukemia. However, the nature of this disease has not been well documented in the literature. Here, we provide a technical protocol for characterizing C1498 cells in vitro and for determining the nature of the induced leukemia in vivo. The first part of this procedure is focused on determining the hematopoietic lineage and the stage of differentiation of cultured C1498 cells. To achieve this, multi-parametric flow cytometric staining is used to detect hematopoietic cell markers. Immunofluorescence microscopy, cytochemistry and a May-Gr&#252;nwald Giemsa staining are then performed to assess the expression of myeloperoxidase, the activity of esterases and cellular morphology, respectively. The second part of this protocol is dedicated to describing the leukemia disease that is induced in vivo. The latter can be achieved by determining the frequencies of leukemic and inherent cells in the blood, hematopoietic organs (e.g., bone marrow and spleen) and non-lymphoid tissues (e.g., the liver and lungs) using specific staining and flow cytometry analyses. The nature of the leukemia is then confirmed using May-Gr&#252;nwald Giemsa staining and staining for specific esterases in the bone marrow. Here, we present the results that were obtained using this protocol in age-matched C1498- and PBS-injected mice.

This manuscript provides a technical procedure that can be used to characterize C1498 cell cultures in vitro and the acute leukemia induced in mice after their injection. Phenotypic and functional analyses are performed using flow cytometry, immunofluorescence microscopy, cytochemistry and May-Gr&#252;nwald Giemsa staining.

The intravenous injection of C1498 cells into syngeneic or congenic mice has been performed since 1941. These injections result in the development of ...

A Mouse Model of Fatigue Induced by Peripheral Irradiation

Cancer-related fatigue (CRF) is a distressing and costly condition that often affects patients receiving cancer treatments, including radiation therapy. Here we describe a method using targeted peripheral irradiation to induce fatigue-like behavior in mice. With appropriate shielding, the irradiation targets the lower abdominal/pelvic region of the mouse, sparing the brain, in an effort to model radiation treatment received by individuals with pelvic cancers. We deliver an irradiation dose that is sufficient to induce fatigue-like behavior in mice, measured by voluntary wheel-running activity (VWRA), without causing obvious morbidity. Since wheel running is a normal, voluntary behavior in mice, its use should have little confounding effect on other behavioral tests or biological measures. Hence, wheel running can be used as a feasible outcome measure in understanding the behavioral and biological correlates of fatigue. CRF is a complex condition with frequent comorbidities, and likely has causes related both to cancer and its various treatments. The methods described in this paper are useful for investigating radiation-induced changes that contribute to the development of CRF and, more generally, to explore the biological networks that can explain the development and persistence of a peripherally-triggered but centrally-driven behavior like fatigue.

We describe a method using targeted peripheral irradiation to induce fatigue-like behavior in mice. The selected non-lethal irradiation dose leads to a week-long reduction in voluntary wheel-running activity.

Cancer-related fatigue (CRF) is a distressing and costly condition that often affects patients receiving cancer treatments, including radiation therapy. ...

One-step Protocol for Evaluation of the Mode of Radiation-induced Clonogenic Cell Death by Fluorescence Microscopy

Research on ionizing radiation (IR)-induced clonogenic cell death is important for understanding the effect of IR on malignant tumors and normal tissues. Here, we describe a quick and cost-effective one-step assay for simultaneously assessing the major modes of clonogenic cell death induced by IR, i.e., apoptosis, mitotic catastrophe, and cellular senescence. In this method, cells grown on a cover slip are irradiated with X-rays and stained with 4&#39;,6-diamidino-2-phenylindole dihydrochloride (DAPI). Using fluorescence microscopy, apoptosis, mitotic catastrophe, and cellular senescence are identified based on the characteristic morphologies of the DAPI-stained nuclei. Apoptosis is determined by the presence of apoptotic bodies (i.e., condensed and fragmented nuclei). Mitotic catastrophe is determined by the presence of nuclei that exhibit two or more distinct lobes and micronuclei. Cellular senescence is determined by the presence of senescence-associated heterochromatic foci (i.e., nuclear DNA containing 30-50 bright, dense foci). This approach allows the experimenter to easily screen for clonogenic cell death modes using various cell lines, treatment settings, and/or time points, with the goal of elucidating the mechanisms of cell death in the target cells and conditions of interest.

Research on ionizing radiation (IR)-induced clonogenic cell death is important for understanding the effects of IR on malignant tumors and normal tissues. Here, we describe a one-step assay for assessing the major modes of IR-induced clonogenic cell death based on morphology of 4&#39;,6-diamidino-2-phenylindole dihydrochloride (DAPI)-stained nuclei visualized by fluorescence microscopy.

Research on ionizing radiation (IR)-induced clonogenic cell death is important for understanding the effect of IR on malignant tumors and normal tissues. ...

Isolation and Characterization of Tumor-initiating Cells from Sarcoma Patient-derived Xenografts

The existence and importance of tumor-initiating cells (TICs) have been supported by increasing evidence during the past decade. These TICs have been shown to be responsible for tumor initiation, metastasis, and drug resistance. Therefore, it is important to develop specific TIC-targeting therapy in addition to current chemotherapy strategies, which mostly focus on the bulk of non-TICs. In order to further understand the mechanism behind the malignancy of TICs, we describe a method to isolate and to characterize TICs in human sarcomas. Herein, we show a detailed protocol to generate patient-derived xenografts (PDXs) of human sarcomas and to isolate TICs by fluorescence-activated cell sorting (FACS) using human leukocyte antigen class I (HLA-1) as a negative marker. Also, we describe how to functionally characterize these TICs, including a sphere formation assay and a tumor formation assay, and to induce differentiation along mesenchymal pathways. The isolation and characterization of PDX TICs provide clues for the discovery of potential targeting therapy reagents. Moreover, increasing evidence suggests that this protocol may be further extended to isolate and characterize TICs from other types of human cancers.

We describe a detailed protocol for the isolation of tumor-initiating cells from human sarcoma patient-derived xenografts by fluorescence-activated cell sorting, using human leukocyte antigen-1 (HLA-1) as a negative marker, and for the further validation and characterization of these HLA-1-negative tumor-initiating cells.

The existence and importance of tumor-initiating cells (TICs) have been supported by increasing evidence during the past decade. These TICs have been ...

Isolation Protocol of Mouse Monocyte-derived Dendritic Cells and Their Subsequent In Vitro Activation with Tumor Immune Complexes

Dendritic cells (DC) are heterogeneous cell populations that differ in their cell membrane markers, migration patterns and distribution, and in their antigen presentation and T cell activation capacities. Since most vaccinations of experimental tumor models require millions of DC, they are widely isolated from the bone marrow or spleen. However, these DC significantly differ from blood and tumor DC in their responses to immune complexes (IC), and presumably to other Syk-coupled lectin receptors. Importantly, given the sensitivity of DC to danger-associated molecules, the presence of endotoxins or antibodies that crosslink activation receptors in one of the isolating steps could result in the priming of DC and thus affect the parameters, or at least the dosage, required to activate them. Therefore, here we describe a detailed protocol for isolating MoDC from blood and tumors while avoiding their premature activation. In addition, a protocol is provided for MoDC activation with tumor IC, and their subsequent analyses.

Isolation Protocol of Mouse Monocyte-derived Dendritic Cells and Their Subsequent In Vitro Activation with Tumor Immune Complexes

Monocyte-derived DC (MoDC) can sense minor amounts of danger-associated molecules and are therefore easily primed. We provide a detailed protocol for the isolation of MoDC from blood and tumors and their activation with immune complexes while highlighting key precautions that should be considered in order to avoid their premature activation.

Dendritic cells (DC) are heterogeneous cell populations that differ in their cell membrane markers, migration patterns and distribution, and in their ...

Isolation of Human Endothelial Cells from Normal Colon and Colorectal Carcinoma - An Improved Protocol

Primary cells isolated from human carcinomas are valuable tools to identify pathogenic mechanisms contributing to disease development and progression. In particular, endothelial cells (EC) constituting the inner surface of vessels, directly participate in oxygen delivery, nutrient supply, and removal of waste products to and from tumors, and are thereby prominently involved in the constitution of the tumor microenvironment (TME). Tumor endothelial cells (TECs) can be used as cellular biosensors of the intratumoral microenvironment established by communication between tumor and stromal cells. TECs also serve as targets of therapy. Accordingly, in culture these cells allow studies on mechanisms of response or resistance to anti-angiogenic treatment. Recently, it was found that TECs isolated from human colorectal carcinoma (CRC) exhibit memory-like effects based on the specific TME they were derived from. Moreover, these TECs actively contribute to the establishment of a specific TME by the secretion of different factors. For example, TECs in a prognostically favorable Th1-TME secrete the anti-angiogenic tumor-suppressive factor secreted protein, acidic and rich in cysteine-like 1 (SPARCL1). SPARCL1 regulates vessel homeostasis and inhibits tumor cell proliferation and migration. Hence, cultures of pure, viable TECs isolated from human solid tumors are a valuable tool for functional studies on the role of the vascular system in tumorigenesis. Here, a new up-to-date protocol for the isolation of primary EC from the normal colon as well as CRC is described. The technique is based on mechanical and enzymatic tissue digestion, immunolabeling, and fluorescence activated cell sorting (FACS)-sorting of triple-positive cells (CD31, VE-cadherin, CD105). With this protocol, viable TEC or normal endothelial cell (NEC) cultures could be isolated from colon tissues with a success rate of 62.12% when subjected to FACS-sorting (41 pure EC cultures from 66 tissue samples). Accordingly, this protocol provides a robust approach to isolate human EC cultures from normal colon and CRC.

Tumor endothelial cells are important determinants of the tumor microenvironment and the course of the disease. Here, a protocol for the isolation of pure and viable endothelial cells from human colorectal carcinoma and normal colon to be used in drug testing and pathogenesis research is described.

Primary cells isolated from human carcinomas are valuable tools to identify pathogenic mechanisms contributing to disease development and progression. In ...

Immunophenotyping of Orthotopic Homograft (Syngeneic) of Murine Primary KPC Pancreatic Ductal Adenocarcinoma by Flow Cytometry

Homograft (syngeneic) tumors are the workhorse of today&#39;s immuno-oncology (I/O) preclinical research. The tumor microenvironment (TME), particularly its immune-components, is vital to the prognosis and prediction of treatment outcomes, especially those of immunotherapy. TME immune-components are composed of different subsets of tumor-infiltrating immune cells assessable by multi-color FACS. Pancreatic ductal adenocarcinoma (PDAC) is among the deadliest malignances lacking good treatment options, thus an urgent and unmet medical need. One important reason for its non-responsiveness to various therapies (chemo-, targeted, I/O) has been its abundant TME, consisting of fibroblasts and leukocytes that protect tumor cells from these therapies. Orthotopically implanted PDAC is believed to more accurately recapture the TME of human pancreatic cancers than conventional subcutaneous (SC) models.
Homograft tumors (KPC) are transplants of mouse spontaneous PDAC originating from genetically engineered KPC-mice (KrasG12D/+/P53-/-/Pdx1-Cre) (KPC-GEMM). The primary tumor tissue is cut into small fragments (~2 mm3) and transplanted subcutaneously (SC) to the syngeneic recipients (C57BL/6, 7&#8211;9 weeks old). The homografts were then surgically orthotopically transplanted onto the pancreas of new C57BL/6 mice, along with SC-implantation, which reached tumor volumes of 300&#8211;1,000 mm3 by 17 days. Only tumors of 400&#8211;600 mm3 were harvested per approved autopsy procedure and cleaned to remove the adjacent non-tumor tissues. They were dissociated per protocol using a tissue dissociator into single-cell suspensions, followed by staining with designated panels of fluorescently-labeled antibodies for various markers of different immune cells (lymphoid, myeloid and NK, DCs). The stained samples were analyzed using multi-color FACS to determine numbers of immune cells of different lineages, as well as their relative percentage within tumors. The immune profiles of orthotopic tumors were then compared to those of SC tumors. The preliminary data demonstrated significantly elevated infiltrating TILs/TAMs in tumors over the pancreas, and higher B-cell infiltration into orthotopic rather than SC tumors.

Immunophenotyping of Orthotopic Homograft Syngeneic of Murine Primary KPC Pancreatic Ductal Adenocarcinoma by Flow Cytometry

The experimental procedure on the immunophenotyping of murine orthotopic PDAC homografts aims at profiling the tumor immuno-microenvironment. Tumors are orthotopically implanted via surgery. Tumors of 200&#8211;600 mm3 in size were harvested and dissociated to prepare single-cell suspensions, followed by multi-immune marker FACS analysis using different fluorescently-labeled antibodies.

Homograft (syngeneic) tumors are the workhorse of today&#39;s immuno-oncology (I/O) preclinical research. The tumor microenvironment (TME), particularly ...

Synthesis and Characterization of Placental Chondroitin Sulfate A (plCSA)-Targeting Lipid-Polymer Nanoparticles

An effective cancer therapeutic method reduces and eliminates tumors with minimal systemic toxicity. Actively targeting nanoparticles offer a promising approach to cancer therapy. The glycosaminoglycan placental chondroitin sulfate A (plCSA) is expressed on a wide range of cancer cells and placental trophoblasts, and malarial protein VAR2CSA can specifically bind to plCSA. A reported placental chondroitin sulfate A binding peptide (plCSA-BP), derived from malarial protein VAR2CSA, can also specifically bind to plCSA on cancer cells and placental trophoblasts. Hence, plCSA-BP-conjugated nanoparticles could be used as a tool for targeted drug delivery to human cancers and placental trophoblasts. In this protocol, we describe a method to synthesize plCSA-BP-conjugated lipid-polymer nanoparticles loaded with doxorubicin (plCSA-DNPs); the method consists of a single sonication step and bioconjugate techniques. In addition, several methods for characterizing plCSA-DNPs, including determining their physicochemical properties and cellular uptake by placental choriocarcinoma (JEG3) cells, are described.

Synthesis and Characterization of Placental Chondroitin Sulfate A plCSA-Targeting Lipid-Polymer Nanoparticles

Here, we present a protocol for the synthesis of placental chondroitin sulfate A binding peptide (plCSA-BP)-conjugated lipid-polymer nanoparticles via single-step sonication and bioconjugate techniques. These particles constitute a novel tool for the targeted delivery of therapeutics to most human tumors and placental trophoblasts to treat cancers and placental disorders.

An effective cancer therapeutic method reduces and eliminates tumors with minimal systemic toxicity. Actively targeting nanoparticles offer a promising ...

Spatial and Temporal Control of Murine Melanoma Initiation from Mutant Melanocyte Stem Cells

Cutaneous melanoma is well known as the most aggressive skin cancer. Although the risk factors and major genetic alterations continue to be documented with increasing depth, the incidence rate of cutaneous melanoma has shown a rapid and continuous increase during recent decades. In order to find effective preventative methods, it is important to understand the early steps of melanoma initiation in the skin. Previous data has demonstrated that follicular melanocyte stem cells (MCSCs) in the adult skin tissues can act as melanoma cells of origin when expressing oncogenic mutations and genetic alterations. Tumorigenesis arising from melanoma-prone MCSCs can be induced when MCSCs transition from a quiescent to active state. This transition in melanoma-prone MCSCs can be promoted by the modulation of either hair follicle stem cells&#39; activity state or through extrinsic environmental factors such as ultraviolet-B (UV-B). These factors can be artificially manipulated in the laboratory by chemical depilation, which causes transition of hair follicle stem cells and MCSCs from a quiescent to active state, and by UV-B exposure using a benchtop light. These methods provide successful spatial and temporal control of cutaneous melanoma initiation in the murine dorsal skin. Therefore, these in vivo model systems will be valuable to define the early steps of cutaneous melanoma initiation and could be used to test potential methods for tumor prevention.

The following procedure describes a method for spatial and temporal control of melanocytic tumor initiation in murine dorsal skin, using a genetically engineered mouse model. This protocol describes macroscopic as well as microscopic cutaneous melanoma initiation.

Cutaneous melanoma is well known as the most aggressive skin cancer. Although the risk factors and major genetic alterations continue to be documented ...

Isolation of Primary Cancer-Associated Fibroblasts from a Syngeneic Murine Model of Breast Cancer for the Study of Targeted Nanoparticles

Cancer-associated fibroblasts (CAFs) are key actors in the context of the tumor microenvironment. Despite being reduced in number as compared to tumor cells, CAFs regulate tumor progression and provide protection from antitumor immunity. Emerging anticancer strategies aim to remodel the tumor microenvironment through the ablation of pro-tumorigenic CAFs or reprogramming of CAFs functions and their activation status. A promising approach is the development of nanosized delivery agents able to target CAFs, thus allowing the specific delivery of drugs and active molecules. In this context, a cellular model of CAFs may provide a useful tool for in vitro screening and preliminary investigation of such nanoformulations.
This study describes the isolation and culture of primary CAFs from the syngeneic 4T1 murine model of triple-negative breast cancer. Magnetic beads were used in a 2-step separation process to extract CAFs from dissociated tumors. Immunophenotyping control was performed using flow cytometry after each passage to verify the process yield. Isolated CAFs can be employed to study the targeting capability of different nanoformulations designed to tackle the tumor microenvironment. Fluorescently labeled H-ferritin nanocages were used as candidate nanoparticles to set up the method. Nanoparticles, either bare or conjugated with a targeting ligand, were analyzed for their binding to CAFs. The results suggest that ex vivo extraction of breast CAFs may be a useful system to test and validate nanoparticles for the specific targeting of tumorigenic CAFs.

This paper aims to provide a protocol for the isolation and culture of primary cancer-associated fibroblasts from a syngeneic murine model of triple-negative breast cancer and their application for the preclinical study of novel nanoparticles designed to target the tumor microenvironment.&#160;

Cancer-associated fibroblasts (CAFs) are key actors in the context of the tumor microenvironment. Despite being reduced in number as compared to tumor ...