Interleukin 2 induction of pore-forming protein gene expression in human peripheral blood CD8+ T cells.
Our studies have analyzed pore-forming protein (PFP) mRNA expression in resting and stimulated human peripheral blood CD3- large granular lymphocytes (LGL), CD3+ T cells, and their CD4+ or CD8+ subsets. Signals that stimulate T cells to develop cytotoxic activity (i.e., IL-2 or OKT-3 mAb) led to the induction of PFP mRNA in T cells. The data indicated that IL-2 directly increased PFP mRNA in the CD8+ subset of T cells, in the absence of new DNA or protein synthesis. Abrogation of IL-2-induced PFP mRNA expression and cytotoxic potential of T cells by the anti-p75 IL-2 receptor mAb suggested that low numbers of p75 IL-2 receptors on CD8+ T cells were capable of transducing signals responsible for these IL-2-induced effects. The induction of T cell PFP mRNA via CD3, using OKT-3 mAb, was less rapid but greater than that caused by IL-2; however, a combination of PMA and ionomycin, which bypasses crosslinking of the TCR/CD3 complex, could not mimic this increase in PFP mRNA levels in T cells. The role of second messenger systems in regulating PFP mRNA expression remains to be determined. In contrast, high constitutive PFP mRNA expression was observed in CD3- LGL and these mRNA levels could not be enhanced by stimulation with IL-2. The cytotoxic potential of peripheral blood T cells and LGL induced in response to IL-2 correlated with IL-2-induced PFP mRNA levels in these cells and was consistent with PFP being one of several important molecules involved in the effector function of cytotoxic lymphocytes.
Laboratory of Experimental Immunology, National Cancer Institute-Frederick Cancer Research Facility, Maryland 21701.
M J
MJ
Smyth
J R
JR
Ortaldo
Y
Y
Shinkai
H
H
Yagita
M
M
Nakata
K
K
Okumura
H A
HA
Young
D000911:Antibodies, Monoclonal; D015703:Antigens, CD / Q000032:analysis; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D017252:CD3 Complex; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic; D015870:Gene Expression / Q000187:drug effects*; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis; D007376:Interleukin-2 / Q000494:pharmacology*; D007700:Kinetics; D008213:Lymphocyte Activation; D008562:Membrane Glycoproteins; D008565:Membrane Proteins / Q000235:genetics*; D054353:Perforin; D052899:Pore Forming Cytotoxic Proteins; D012313:RNA / Q000097:blood / Q000235:genetics / Q000302:isolation & purification; D012333:RNA, Messenger / Q000235:genetics; D011948:Receptors, Antigen, T-Cell / Q000032:analysis; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*
D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D017252:CD3 Complex; D007376:Interleukin-2; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D052899:Pore Forming Cytotoxic Proteins; D012333:RNA, Messenger; D011948:Receptors, Antigen, T-Cell; D054353:Perforin; D012313:RNA; D007371:Interferon-gamma