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Clinical assessment (disease activity, severity, and extraarticular manifestations) of 101 rheumatoid arthritis patients was correlated with several laboratory tests, including 5 immune complex assays: the bovine conglutinin, 125I–C1q binding, monoclonal rheumatoid factor inhibition, Raji cell, and staphylococci binding assays. Elevated disease activity indices were most closely associated with the presence of immune complexes detected by the 125I–C1q and staphylococci binding assays. There were significant but weak correlations between the level of disease activity and the level of immune complexes as measured by the bovine conglutinin, 125I–C1q binding, Raji cell, and staphylococci binding assays. Articular disease severity, as measured by anatomic stage, was best discriminated by the bovine conglutinin, monoclonal rheumatoid factor inhibition, and staphylococci binding assays. Extraarticular manifestations were best discriminated by the Raji cell and staphylococci binding assays. We concluded that the sensitivity, specificity, predictive value, and overlap of the associations were not sufficient to warrant their wide use for the diagnosis and management of rheumatoid arthritis in individual patients. Conversely, the 125I–C1q and staphylococci binding assays were as good as the erythrocyte sedimentation rate and the IgG rheumatoid factor test (the 2 best tests of many examined) in assessing disease activity. Further prospective studies with these assays will determine their usefulness in following rheumatoid arthritis for a prolonged period.

SummarySerum samples from 85 Austrian hemophilia patients treated with lyophilized factor concentrates prepared from U.S. plasma sources, 24 hemophilia patients from Georgia on a home therapy program with factor concentrates, and 10 U.S. hemophilia patients with acquired immunodeficiency syndrome (AIDS) were analyzed by two different methods for the presence of antibodies to the major internal antigen of human T-cell leukemia virus I (HTLV-I) p24. All but one, a Georgia sample, were negative. The absence of antibody to HTLV-I p24 in the serum of European hemophilia patients, of U.S. hemophilia patients with no symptoms of AIDS, and of U.S. hemophilia patients with AIDS is interpreted as an indication of the lack of ready transmissibility of HTLV-I in lyophilized factor concentrates.

The penetration of CD4+ cells by human immunodeficiency virus (HIV) involves a high affinity interaction between the viral attachment protein, gp120, and the cellular receptor, CD4. The mechanism by which the virus penetrates the host cell subsequent to viral binding is unknown. We have investigated the possibility that HIV penetration induces changes in the metabolic state of the infected cell similar to those seen with the perturbation of CD4 cells by monoclonal antibodies (MAb) directed against the CD4 molecule, or with specific antigen-mediated activation. The activation of cellular protein kinases was examined. The basal level of activity was not altered in the presence of HIV. Kinase activity was markedly increased in cells stimulated with phytohemagglutinin (PHA), and was qualitatively and quantitatively changed by a brief exposure to the phorbol ester TPA (12-o-tetradecanoyl phorbol-13-acetate). The phosphorylation state of the CD4 molecule was examined by radioimmunoprecipitation and found to be unaltered by the binding of HIV under conditions in which TPA induced rapid CD4 phosphorylation. The activity of the CD4-associated protein tyrosine kinase p56lck was measured by in vitro assays of 32PO4 incorporation in CD4 immunoprecipitates from HIV-incubated cells. TPA incubation resulted in a rapid loss of CD4-associated p56lck activity, presumably due to dissociation of the enzyme from CD4. Concanavalin A stimulation resulted in a similar change but with a slower time course. However, no change in CD4-associated activity was detected in HIV-incubated cells. We found that Ca2+ influx was not induced by the binding of HIV to CD4+ cells.(ABSTRACT TRUNCATED AT 250 WORDS)