Accessory cell-dependent T-cell activation via Ti-CD3. Involvement of CD2-LFA-3 interactions.
The activation of resting T cells to interleukin 2 (IL-2) production and DNA synthesis via Ti-CD3 is dependent on accessory cells (AC). Using positively selected, resting T cells activated with particle-bound anti-CD3, we investigated the ability of various cell lines to function as AC. We found that cell lines able to act as AC all expressed LFA-3, while cell lines not expressing LFA-3 were unable to provide AC signals. This applied to CD3+, CD4+, and CD8+ T cells. Sheep red blood cells (SRBC), which express LFA-3-like molecules, also had a weak, but significant AC function in this test system. Both CD4+ and CD8+ T cells activated with particle-bound anti-CD3 could be induced to enter DNA synthesis in the absence of AC when monoclonal antibodies reacting with CD2 were present instead of AC. IL-2 production could be detected in the latter cultures but not when positively selected CD3+ or CD2+ T cells were cultured alone. Our data suggest that activation of resting T cells via CD3 will lead to IL-2 receptor expression, while the interactions between LFA-3 and its ligand CD2 provide the necessary secondary signals for IL-2 production and induction of DNA synthesis.
Halvorsen
R
R
Institute of Transplantation Immunology, National Hospital, Oslo, Norway.
Leivestad
T
T
Gaudernack
G
G
Thorsby
E
E
D000818:Animals; D000911:Antibodies, Monoclonal / Q000502:physiology; D000938:Antigen-Presenting Cells / Q000145:classification / Q000276:immunology*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology*; D000954:Antigens, Surface / Q000276:immunology*; D018801:CD2 Antigens; D017252:CD3 Complex; D018968:CD58 Antigens; D002460:Cell Line; D004912:Erythrocytes / Q000276:immunology; D006801:Humans; D007376:Interleukin-2 / Q000096:biosynthesis; D008213:Lymphocyte Activation; D008562:Membrane Glycoproteins / Q000276:immunology*; D010641:Phenotype; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D011971:Receptors, Immunologic / Q000276:immunology*; D012756:Sheep; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D050378:T-Lymphocytes, Regulatory / Q000145:classification / Q000276:immunology
D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D018801:CD2 Antigens; D017252:CD3 Complex; D018968:CD58 Antigens; D007376:Interleukin-2; D008562:Membrane Glycoproteins; D011948:Receptors, Antigen, T-Cell; D011971:Receptors, Immunologic