Human leukocyte antigen-class II-positive human corneal epithelial cells activate allogeneic T cells.
OBJECTIVE
To achieve a better understanding of the mechanism of corneal immune diseases, including corneal allograft rejection, the authors examined the potential of human corneal epithelial (HCE) cells to activate allogeneic T lymphocytes.


METHODS
The mixed lymphocyte-HCE cell reaction (MLCER) was performed as follows: HCE cells from primary cultures, with or without treatment with interferon-gamma (IFN-gamma), were treated with mitomycin C and then mixed with peripheral blood lymphocytes (PBL) from normal volunteers. Triplicate cultures were incubated for 7 days. Interleukin-1-alpha (IL-1-alpha) was added to some cultures to examine its effect on MLCER: The lymphocyte responses were measured by 3H-thymidine uptake for the last 18 hours of incubation in MLCER:


RESULTS
IFN-gamma-treated, HLA-class-II-bearing HCE cells stimulated allogenic lymphocytes, whereas IFN-gamma nontreated, class-II-negative HCE cells did not. The stimulation by IFN-gamma-treated HCE cells was blocked by anti-HLA class II monoclonal antibody. In addition, exogenous IL-1-alpha reduced the lymphocyte response in MLCER: This effort was inhibited by indomethacin.


CONCLUSIONS
This study demonstrates that HLA-class-II-bearing HCE cells can activate allogeneic PBL by a major histocompatibility complex class II-dependent mechanism. In addition, HCE cells may regulate immune reactions, probably through prostaglandin production caused by IL-1.
Department of Ophthalmology, University of Pittsburgh School of Medicine, Pennsylvania.
M
M
Iwata
A
A
Yagihashi
M I
MI
Roat
A
A
Zeevi
Y
Y
Iwaki
R A
RA
Thoft
D000938:Antigen-Presenting Cells / Q000276:immunology; D002478:Cells, Cultured; D003315:Cornea / Q000166:cytology / Q000187:drug effects / Q000276:immunology*; D004848:Epithelium / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D007375:Interleukin-1 / Q000096:biosynthesis / Q000494:pharmacology; D007519:Isoantigens / Q000276:immunology*; D008213:Lymphocyte Activation / Q000276:immunology*; D007959:Lymphocyte Culture Test, Mixed; D016685:Mitomycin / Q000494:pharmacology; D011994:Recombinant Proteins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000276:immunology*
D000949:Histocompatibility Antigens Class II; D007375:Interleukin-1; D007519:Isoantigens; D011994:Recombinant Proteins; D016685:Mitomycin; D007371:Interferon-gamma