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Cytotoxic T lymphocytes reactive against a syngeneic murine tumor and their specific suppressor T cells are both elicited by in vitro allosensitization
Sensitization of C57BL/6 (B6, H-2b) splenocytes against normal BALB/c (H-2d) leukocytes (B6 a/BALB) in bulk MLC induced CTL reactive against the syngeneic (H-2b) nonimmunogenic lymphoma PIR-2, in addition to the CTL directed against the corresponding (H-2d) allotargets. However, MLC- derived lymphoc...
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Lenguaje: | English |
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The Rockefeller University Press
1990
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2187835/ https://www.ncbi.nlm.nih.gov/pubmed/2139097 |
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collection | PubMed |
description | Sensitization of C57BL/6 (B6, H-2b) splenocytes against normal BALB/c (H-2d) leukocytes (B6 a/BALB) in bulk MLC induced CTL reactive against the syngeneic (H-2b) nonimmunogenic lymphoma PIR-2, in addition to the CTL directed against the corresponding (H-2d) allotargets. However, MLC- derived lymphocytes did not directly exhibit anti-PIR-2 cytotoxicity in spite of the high anti-PIR-2 CTL frequency (up to 1/20) among them, as demonstrated by the limiting dilution culture (LDC) technique. The present study was undertaken to resolve this contradiction. We found that anti-PIR-2 cytotoxicity could be detected only when B6 a/BALB MLC- derived responding cells were plated in LDC at low numbers (less than 200) of cells/well. In contrast, increasing the number of the plated cells to 500-5,000 resulted in a gradual decrease in the percentage of wells cytotoxically reactive against PIR-2, whereas the percentage of wells exhibiting cytotoxicity against the allotargets remained unchanged (100%). This decrease of anti-PIR-2 cytotoxicity in LDC and the lack of anti-PIR-2 reactivity among MLC-derived lymphocytes were shown by mixing experiments to result from the activity of radioresistant Thy-1+, Lyt-2+, L3T4- suppressor cells, blocking the anti-PIR-2 cytotoxicity at the effector phase. The suppression was specific as indicated by the following observations: (a) freshly obtained B6 splenocytes, cultured unsensitized B6 splenocytes, mitogen- induced B6 lymphoblasts, B6 LAK cells, or B6 a/B6 MLC-derived lymphocytes were not suppressive; (b) anti-PIR-2 cytotoxicity elicited in B6 a/BALB LDC was suppressed only by lymphocytes derived from B6 a/BALB MLC and not from B6 a/C3H (H-2k) MLC; and (c) B6 a/BALB MLC- induced suppressor cells could be adsorbed on monolayers of BALB/c but not of C3H lymphoblasts. Since both syngeneic tumor and allogeneic target cells were lysed by the same clonal cell population but only the antisyngeneic activity was suppressed, we suggest that a single CTL can exhibit two cytotoxic activities that are differentially affected by the described suppressor cells. This mode of suppression may play a role in controlling autoimmune reactivity. |
format | Text |
id | pubmed-2187835 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 1990 |
publisher | The Rockefeller University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-21878352008-04-17 Cytotoxic T lymphocytes reactive against a syngeneic murine tumor and their specific suppressor T cells are both elicited by in vitro allosensitization J Exp Med Articles Sensitization of C57BL/6 (B6, H-2b) splenocytes against normal BALB/c (H-2d) leukocytes (B6 a/BALB) in bulk MLC induced CTL reactive against the syngeneic (H-2b) nonimmunogenic lymphoma PIR-2, in addition to the CTL directed against the corresponding (H-2d) allotargets. However, MLC- derived lymphocytes did not directly exhibit anti-PIR-2 cytotoxicity in spite of the high anti-PIR-2 CTL frequency (up to 1/20) among them, as demonstrated by the limiting dilution culture (LDC) technique. The present study was undertaken to resolve this contradiction. We found that anti-PIR-2 cytotoxicity could be detected only when B6 a/BALB MLC- derived responding cells were plated in LDC at low numbers (less than 200) of cells/well. In contrast, increasing the number of the plated cells to 500-5,000 resulted in a gradual decrease in the percentage of wells cytotoxically reactive against PIR-2, whereas the percentage of wells exhibiting cytotoxicity against the allotargets remained unchanged (100%). This decrease of anti-PIR-2 cytotoxicity in LDC and the lack of anti-PIR-2 reactivity among MLC-derived lymphocytes were shown by mixing experiments to result from the activity of radioresistant Thy-1+, Lyt-2+, L3T4- suppressor cells, blocking the anti-PIR-2 cytotoxicity at the effector phase. The suppression was specific as indicated by the following observations: (a) freshly obtained B6 splenocytes, cultured unsensitized B6 splenocytes, mitogen- induced B6 lymphoblasts, B6 LAK cells, or B6 a/B6 MLC-derived lymphocytes were not suppressive; (b) anti-PIR-2 cytotoxicity elicited in B6 a/BALB LDC was suppressed only by lymphocytes derived from B6 a/BALB MLC and not from B6 a/C3H (H-2k) MLC; and (c) B6 a/BALB MLC- induced suppressor cells could be adsorbed on monolayers of BALB/c but not of C3H lymphoblasts. Since both syngeneic tumor and allogeneic target cells were lysed by the same clonal cell population but only the antisyngeneic activity was suppressed, we suggest that a single CTL can exhibit two cytotoxic activities that are differentially affected by the described suppressor cells. This mode of suppression may play a role in controlling autoimmune reactivity. The Rockefeller University Press 1990-04-01 /pmc/articles/PMC2187835/ /pubmed/2139097 Text en This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/). |
spellingShingle | Articles Cytotoxic T lymphocytes reactive against a syngeneic murine tumor and their specific suppressor T cells are both elicited by in vitro allosensitization |
title | Cytotoxic T lymphocytes reactive against a syngeneic murine tumor and their specific suppressor T cells are both elicited by in vitro allosensitization |
title_full | Cytotoxic T lymphocytes reactive against a syngeneic murine tumor and their specific suppressor T cells are both elicited by in vitro allosensitization |
title_fullStr | Cytotoxic T lymphocytes reactive against a syngeneic murine tumor and their specific suppressor T cells are both elicited by in vitro allosensitization |
title_full_unstemmed | Cytotoxic T lymphocytes reactive against a syngeneic murine tumor and their specific suppressor T cells are both elicited by in vitro allosensitization |
title_short | Cytotoxic T lymphocytes reactive against a syngeneic murine tumor and their specific suppressor T cells are both elicited by in vitro allosensitization |
title_sort | cytotoxic t lymphocytes reactive against a syngeneic murine tumor and their specific suppressor t cells are both elicited by in vitro allosensitization |
topic | Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2187835/ https://www.ncbi.nlm.nih.gov/pubmed/2139097 |