Rat thyroid epithelial cells provide limited accessory function but fail to present allo antigens in vitro.
Human and mouse thyroid epithelial cells (TEC) have been reported to exhibit a number of immunological activities including partial, but not total, antigen presenting capability. In the studies described here, the thyroid stimulating hormone-dependent rat thyroid epithelial cell line FRTL-5 was tested for its abilities to provide accessory and antigen presenting cell (APC) activity. FRTL-5 cells alone were not able to function as accessory cells for ConA induced polyclonal proliferation of purified T-cells and were not capable of inducing alloreactive T-cell proliferation in mixed lymphocyte reaction (MLR) cultures. Furthermore, even following the induction and enhanced expression of MHC class II and class I MHC products, respectively by IFN-gamma, FRTL-5, cells could not function as accessory cells or induce alloreactive T-cell proliferation as the singular stimulatory population in MLR cultures. However, these epithelial cells could effectively synergize with either low numbers of spleen cells, or with supernatants from activated T-cells, to provide accessory function in ConA stimulated cultures. These findings suggest that hormone-dependent and functional rat TEC cannot directly activate resting syngeneic or unprimed allogeneic T-cells, although they can provide at least one accessory cell signal involved in T-cell activation by mitogen. Thus, the results presented here do not support contentions that such a nonhemopoietic resident cell population is capable of directly triggering the initial activation of anti-thyroid specific T-cells.
Sigillito
R J
RJ
Department of Microbiology and Immunology, University of Miami School of Medicine, FL 33101.
Miller
S
S
Tokuda
N
N
Levy
R B
RB
D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology*; D002460:Cell Line; D003208:Concanavalin A / Q000494:pharmacology; D004848:Epithelium / Q000276:immunology; D005260:Female; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D007371:Interferon-gamma / Q000494:pharmacology; D007519:Isoantigens / Q000276:immunology*; D008213:Lymphocyte Activation / Q000187:drug effects / Q000276:immunology; D051381:Rats; D011917:Rats, Inbred Lew; D011994:Recombinant Proteins; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology; D013961:Thyroid Gland / Q000166:cytology / Q000276:immunology*
D000949:Histocompatibility Antigens Class II; D007519:Isoantigens; D011994:Recombinant Proteins; D003208:Concanavalin A; D007371:Interferon-gamma