title: Appearance and evolution of anti-Da (B cell-specific) antibodies after planned immunizations.
abstract: Appearance and evolution of anti-Da antibodies has been followed in eight volunteers immunized by whole blood transfusions or leukocyte intradermal injections form a single donor incompatible for HLA--A,--B,--C and--D specificities. Several unabsorbed bleedings from each recipient were studied against the specific immunizer with three different complement-dependent lymphocytotoxicity (CdL) techniques: (1) standard NIH CdL on total peripheral blood lymphocytes (PBL); (2) VII Workshop standard CdL technique on B cell-enriched suspensions; (3) beta2 microglobulin blanketing test ("bb" test) on B cells. Results obtained with the "bb" test were confirmed with platelet-absorbed sera. The "bb" and the absorbed sera allow discrimination between anti-Da and anti-HLA--A,--B,--C antibodies. Stage of appearance and evolution are rather similar for an anti-HLA--A,--B,--C and anti-Da. An early appearance of antibodies positive only against B cells is due to weak anti-HLA--A,--B antibodies which react better with B cells than with total PBL. Immunogenicity of Da antigens seems to be of the same order as HLA--A, and--B. In fact, Da reactivity was present in all eight recipients studied. These reactivities always segregated in familes with these HLA haplotypes. On a small panel of unrelated D-typed donors, three sera showed a significant positive association with D alleles.
mesh_terms: D000918:Antibody Specificity; D001402:B-Lymphocytes / Q000276:immunology*; D001803:Blood Transfusion; D003165:Complement System Proteins; D006680:HLA Antigens; D006650:Histocompatibility Testing; D006801:Humans; D007106:Immune Sera; D007117:Immunization, Secondary; D001613:beta 2-Microglobulin / Q000276:immunology
chemical_list: D006680:HLA Antigens; D007106:Immune Sera; D001613:beta 2-Microglobulin; D003165:Complement System Proteins