title: In situ evaluation of immunoglobulin synthesis of synovial plasma cells in rheumatoid arthritis and osteoarthritis by plug photometry.
abstract: Synovial membranes of patients with osteoarthritis--a disease with unaltered immunoregulation--and rheumatoid arthritis were immunostained for the different immunoglobulin isotypes using the PAP-method and a two-layer alkaline phosphatase technique. Randomly selected plasma cells with positive immunostaining were measured by plug photometry. The average extinction of the single plasma cell is considered to be indicative of the immunoglobulin synthesis of the measured plasma cell and the isotype under study. When we compared both disease entities, patients with rheumatoid arthritis were characterized (i) by higher average extinction values for all Ig-isotypes except IgG (ii) by a higher rate of high producer plasma cells. From this data, we conclude that immunophotometry is a new in vivo method for discriminating two types of synovitis (i) one without increased Ig-synthesis at the single cell level and (ii) a second one with increased Ig-synthesis.
mesh_terms: D000921:Antibody-Producing Cells / Q000166:cytology / Q000276:immunology; D001172:Arthritis, Rheumatoid / Q000276:immunology* / Q000473:pathology; D006801:Humans; D007070:Immunoglobulin A / Q000096:biosynthesis; D007074:Immunoglobulin G / Q000096:biosynthesis; D007075:Immunoglobulin M / Q000096:biosynthesis; D007136:Immunoglobulins / Q000096:biosynthesis*; D010003:Osteoarthritis / Q000276:immunology* / Q000473:pathology; D013583:Synovial Membrane / Q000276:immunology* / Q000473:pathology
chemical_list: D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007136:Immunoglobulins