title: Characterization of the subpopulations of human peripheral blood B lymphocytes which react to staphylococcus aureus Cowan I and T-cell help.
abstract: Staphylococcus aureus Cowan I strain (SAC) activates human peripheral blood B lymphocytes to proliferate but does not induce secretion of immunoglobulin (Ig) unless pokeweed mitogen (PWM)-activated T cells are added. Using a Percoll gradient separation method, we show that a B-cell subpopulation isolated at 50/60% Percoll interface is the target for SAC stimulation. After SAC activation, small, dense B cells become larger, less-dense B cells which proliferate. These activated B blasts differentiate into Ig-secreting cells when cultured with PWM-activated T cells. The culture supernatant of PWM-activated T cells is capable of supporting proliferation and Ig secretion of the activated B blasts but not of resting small B cells. This result suggests that the culture supernatant contains B-cell growth factors.
mesh_terms: D000328:Adult; D000921:Antibody-Producing Cells / Q000145:classification / Q000166:cytology / Q000276:immunology; D001402:B-Lymphocytes / Q000145:classification* / Q000166:cytology / Q000276:immunology; D002454:Cell Differentiation; D002469:Cell Separation; D006133:Growth Substances / Q000502:physiology; D006462:Hemolytic Plaque Technique; D006801:Humans; D015847:Interleukin-4; D015848:Interleukin-5; D008213:Lymphocyte Activation; D008222:Lymphokines / Q000502:physiology; D011043:Pokeweed Mitogens / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
chemical_list: D006133:Growth Substances; D015848:Interleukin-5; D008222:Lymphokines; D011043:Pokeweed Mitogens; D015847:Interleukin-4