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Comparative Study
. 1994 May 10;91(10):4185-9.
doi: 10.1073/pnas.91.10.4185.

Participation of target Fas protein in apoptosis pathway induced by CD4+ Th1 and CD8+ cytotoxic T cells

Affiliations
Comparative Study

Participation of target Fas protein in apoptosis pathway induced by CD4+ Th1 and CD8+ cytotoxic T cells

S T Ju et al. Proc Natl Acad Sci U S A. .

Abstract

The results presented here provide evidence that the presence of Fas protein in target cells is essential to permit cytotoxicity (resulting in apoptosis) mediated by cloned CD4+ Th1 cells. Using mitogen-activated B cells as targets, antigen-dependent lysis by CD4+ Th1 effectors was observed with MRL/MpJ+ but not with MRL/MpJ-lpr targets. The congenic MRL/MpJ-lpr strain is defective in Fas expression. Target cells from various lymphoid tissues of C3H.MRL-lpr mice were also resistant to the lectin-dependent cytotoxicity of Th1 effectors, whereas C3H/HeJ targets were sensitive. Moreover, a rapid DNA fragmentation prior to 51Cr release was induced only in C3H/HeJ targets. Thus, cytotoxicity induced by Th1 effectors correlates with target Fas expression. In contrast to Th1 effectors, CD8+ cytotoxic T lymphocytes (CTLs) killed C3H.MRL-lpr targets. When cytotoxicity was assayed in the presence of EGTA and MgCl2, which chelates extracellular Ca2+ [(Ca2+)ext], only C3H.MRL-lpr targets became resistant to CD8+ CTLs. This (Ca2+)ext-independent cytotoxicity of both Th1 and CD8+ effectors could be inhibited with unlabeled C3H/HeJ thymocytes or with a transfectoma carrying a murine Fas-human mu gene construct. In comparison, C3H.MRL-lpr thymocytes and the nontransfected parental cell line were poor inhibitors. Our study demonstrates that CD4+ Th1 cells and CD8+ CTLs differ in their (Ca2+)ext-dependent cytotoxicity but share a (Ca2+)ext-independent cytotoxicity that requires participation of Fas molecules for cytotoxic signal transduction leading to target apoptosis.

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References

    1. Contemp Top Immunobiol. 1977;7:301-61 - PubMed
    1. J Exp Med. 1992 Dec 1;176(6):1521-9 - PubMed
    1. J Exp Med. 1980 Feb 1;151(2):446-66 - PubMed
    1. Immunology. 1980 Jan;39(1):109-17 - PubMed
    1. J Immunol. 1980 Sep;125(3):1256-61 - PubMed

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