Ro/SSA inhibits the autologous mixed lymphocyte reaction.
To test the hypothesis that the Ro/SSA autoantigen can be recognized as antigenic by the human immune system, lymphocytes obtained from normal volunteers were used in in vitro assays evaluating the ability of Ro/SSA (mol. wt 60 kD) to induce B and/or T cell responses. Bovine Ro/SSA strongly inhibited the autologous mixed lymphocyte reaction in a dose-dependent manner without similar effects on concurrently performed allogeneic mixed lymphocyte reactions or T cell proliferation induced by phytohaemagglutinin. Using three colour FACS analysis, Ro/SSA was found to decrease the percentage of CD4+CD45+RA+ T cells in the proliferative, S+(G2+M), phase of the cell cycle. Associated with the decrease in the percentage of suppressor-inducer cells, was the finding that Ro/SSA was able to augment RF production in pokeweed mitogen stimulated cultures of peripheral blood lymphocytes.
Karsh
J
J
Rheumatic Disease Unit, Ottawa General Hospital, University of Ottawa, Ontario, Canada.
Harley
J B
JB
Goldstein
R
R
Lazarovits
A I
AI
D000328:Adult; D000818:Animals; D015703:Antigens, CD / Q000032:analysis; D019011:Antigens, CD7; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D001324:Autoantigens / Q000276:immunology*; D015704:CD4 Antigens / Q000032:analysis; D002417:Cattle; D006801:Humans; D007075:Immunoglobulin M / Q000096:biosynthesis; D017493:Leukocyte Common Antigens / Q000032:analysis; D008213:Lymphocyte Activation; D007959:Lymphocyte Culture Test, Mixed; D008875:Middle Aged; D020733:RNA, Small Cytoplasmic; D012217:Rheumatoid Factor / Q000096:biosynthesis; D012261:Ribonucleoproteins / Q000276:immunology*; D013045:Species Specificity; D013601:T-Lymphocytes / Q000276:immunology; D000099207:SS-A Antigen
D015703:Antigens, CD; D019011:Antigens, CD7; D000945:Antigens, Differentiation, T-Lymphocyte; D001324:Autoantigens; D015704:CD4 Antigens; D007075:Immunoglobulin M; D017493:Leukocyte Common Antigens; D020733:RNA, Small Cytoplasmic; D012217:Rheumatoid Factor; D012261:Ribonucleoproteins; D000099207:SS-A Antigen; C116006:RO60 protein, human