The effects of dilution on the outcome of pooled plasma testing with HIV type 1 (HIV-1) RNA genome amplification as compared to the outcome of individual-unit testing with other HIV-1 markers.

Background: Proposed testing of large plasma pools with genome amplification technology (GAT) for detection of transfusion-transmissible viruses may have unanticipated complications not associated with individual unit testing. One such potential complication, the effect of dilution resulting from pool formation, was the subject of the present study.

Study Design And Methods: Specimens from three plasma donor HIV type 1 (HIV-1) seroconversion panels were tested with a quantitative HIV-1 RNA GAT assay (lower detection limit, 400 copies).

Platelet activation in patients with sickle cell disease.

Vascular occlusion and vasculopathy underlie much of the morbidity in patients with sickle cell anaemia. Platelets may play a role in this vasculopathy. Samples from 43 patients with sickle cell disease (SCD) were examined for evidence of platelet activation using fluorescent-labelled monoclonal antibodies and flow cytometry.

Platelet activation and platelet-erythrocyte aggregates in patients with sickle cell anemia.

Vascular occlusion and vasculopathy underlie much of the morbidity in patients with sickle cell anemia. Platelets may play a role in this vasculopathy. Samples from 12 adults patients with sickle cell anemia were examined for evidence of platelet activation and formation of platelet-erythrocyte aggregates (PEA) using fluorescent-labeled monoclonal antibodies and flow cytometry.

Comparison of two second-generation anti-hepatitis C virus ELISA on 21431 US blood donor samples.

We have compared two different second-generation (2.0) enzyme-linked immunosorbent assays (ELISA) for the presence of antibodies to hepatitis C virus (anti-HCV) in blood from volunteer, unpaid donors. At two separate blood centres, a total of 21,431 donor samples were tested with Abbott Anti-HCV 2.

Circannual variation in lymphocyte subsets, revisited.

Background: Circadian and circannual variations in lymphocyte subsets, especially CD8+ T-lymphocytes, have been reported. This study focuses on CD4+ T-lymphocyte seasonal variation over a 6-year 8-month period.

Study Design And Methods: Lymphocyte subsets were quantitated monthly for four healthy individuals from 1986 through 1992 as part of a flow cytometry quality-control program.

New human monoclonal antibody reagents for detecting C, c, E, e, K1, Jk(a), and Jk(b) red cell antigens.

Using routine methods, human monoclonal Rh, Kell, and Kidd antibody reagents compared favorably with licensed human- source polyclonal antibody reagents when typing random donor blood specimens. In three different clinical trials, using standard methods and both types of reagents, we tested 2,866 samples by tube, 381 samples by slide, and, using only monoclonal antibodies (MAbs), 1,043 samples by microplate. No discrepant typings were found.

Detection of antibodies to human immunodeficiency virus type 2 (HIV-2) in blood donor sera using United States assay methods for anti-HIV type 1.

Twelve serum samples from French blood donors that were uniformly reactive in tests for antibody to human immunodeficiency virus type 2 (anti-HIV-2) also were reactive in 92 to 100 percent of tests with three anti-HIV type 1 (anti-HIV-1) enzyme-linked immunoassays currently in widespread use for donor screening in the United States. Supplemental tests for anti-HIV-1 on these anti-HIV-2-reactive samples differed in their responses. All samples reacted in a licensed anti-HIV-1 Western blot, but there was an atypical band near the p41 position, which could be a clue to the fact that this result was a cross-reaction with anti-HIV-2.

Effects of serial plasmapheresis on serum IgA levels in IgA-deficient blood donors with IgA-suppressor T cells.

Seventeen IgA-deficient blood donors, without antibodies to IgA, underwent plasmapheresis four to eight consecutive times at intervals of 8 weeks or less to provide fresh-frozen plasma for patients with anti-IgA. Blood samples, drawn for analysis no more than 1 hour before plasmapheresis and again at the conclusion of each procedure, were analyzed for lymphocyte subpopulations and serum IgA levels. Five lymphocyte subpopulations, including natural killer cells, the suppressor-inducer CD4 subset, the suppressor-precursor CD8 subset, non-major histocompatibility complex (MHC)-restricted cytotoxic T cells, and CD5+ B cells, were all decreased significantly after plasmapheresis (p less than 0.

Prevalence of antibody to hepatitis C virus in a blood donor population.

Blood samples from 2000 accepted blood donors and 343 deferred donors with antibody to hepatitis B core antigen (anti-HBc) and/or an alanine aminotransferase (ALT) elevation were evaluated for antibody to hepatitis C virus (anti-HCV). Sixteen (0.8%) of the 2000 sera initially reacted on enzyme-linked immunosorbent assay (ELISA); 12 (0.