title: Activation of human B lymphocytes. XV. Spontaneously occurring and mitogen-induced indirect anti-sheep red blood cell plaque-forming cells in normal human peripheral blood.
abstract: A system for the development of indirect (IgG, IgA, and IgM) anti-SRBC plaque-forming cells (PFC) after polyclonal stimulation of human peripheral blood lymphocytes with pokeweed mitogen (PWM) is described. Rabbit anti-human polyvalent Ig or Ig class-specific antisera were employed. Most of the indirect PFC were IgG with less being IgM and IgA. The finding of significantly more indirect IgM PFC than direct PFC suggests that many IgM PFC are producing low efficiency hemolysin that requires an anti-globulin to produce lysis. The system is T cell dependent and cultures require selected batches of supplemented fetal calf serum that preferentially yield indirect (1527 +/- 243 PFC/10(6) lymphocytes) as opposed to direct (36 +/- 11 PFC/10(6) lymphocytes) PFC. Batches of human AB sera that were previously chosen to yield optimal direct PFC (approximately 200 to 300 PFC/10(6) lymphocytes) did not yield indirect PFC. Hence, depending on culture conditions, polyclonal stimulation of human lymphocytes can yield antigen-specific direct and indirect hemolytic PFC.
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D001769:Blood; D003513:Cycloheximide / Q000494:pharmacology; D004912:Erythrocytes / Q000276:immunology; D006462:Hemolytic Plaque Technique; D006801:Humans; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D008213:Lymphocyte Activation; D011043:Pokeweed Mitogens / Q000494:pharmacology*; D011691:Puromycin / Q000494:pharmacology; D012756:Sheep; D013601:T-Lymphocytes / Q000276:immunology; D013997:Time Factors; D014357:Trypsin / Q000494:pharmacology
chemical_list: D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D011043:Pokeweed Mitogens; D011691:Puromycin; D003513:Cycloheximide; D014357:Trypsin