Autoantibodies specific for different isoforms of CD45 in systemic lupus erythematosus.
Nearly one-third of IgM antilymphocyte autoantibody-positive sera from patients with systemic lupus erythematosus (SLE) contain IgM antibodies to one or more 180-220-kD molecules (p180, p190, p205, and p220) in blots of glycoproteins purified from T cells by wheat germ agglutinin affinity chromatography. Identity of these IgM targets with multiple isoforms of CD45 was established by their specific depletion from T cell glycoproteins by immunoprecipitation with T191, a monoclonal antibody (mAb) that reacts with an epitope common to all CD45 isoforms. Although the anti-CD45 autoantibodies recognize higher molecular weight isoforms primarily, antigenic specificity in this system is quite heterogeneous and includes multiple distinct CD45 isoforms on different types of T cells that are, at least in part, different from those reactive with mAbs 2H4 and UCHL-1. Because CD45 is a major membrane protein tyrosine phosphatase that plays a critical role in antigen-induced T cell activation, the present data may be relevant to some of the antilymphocyte antibody-mediated immunologic abnormalities that characterize SLE and related autoimmune diseases.
Mimura
T
T
Division of Rheumatology and Immunology, University of North Carolina, Chapel Hill 27514.
Fernsten
P
P
Jarjour
W
W
Winfield
J B
JB
D015703:Antigens, CD / Q000276:immunology*; D000943:Antigens, Differentiation / Q000276:immunology*; D001323:Autoantibodies / Q000032:analysis*; D004591:Electrophoresis, Polyacrylamide Gel; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006649:Histocompatibility Antigens / Q000276:immunology*; D006801:Humans; D015151:Immunoblotting; D007075:Immunoglobulin M / Q000032:analysis; D017493:Leukocyte Common Antigens; D008180:Lupus Erythematosus, Systemic / Q000276:immunology*; D012016:Reference Values
D015703:Antigens, CD; D000943:Antigens, Differentiation; D001323:Autoantibodies; D006649:Histocompatibility Antigens; D007075:Immunoglobulin M; D017493:Leukocyte Common Antigens