Recombinant interleukin 2 induces immunoglobulin secretion in Staphylococcus aureus Cowan strain I activated human B-cells.
Human B-cells, exhaustively depleted for T-cells, were activated with Staphylococcus aureus Cowan strain I (SAC) and responded to recombinant human interleukin 2 (rIL2) by secretion of immunoglobulin (Ig), as measured by a protein A hemolytic plaque assay. The rIL2, however, had to be present early, since addition later than 24 h after SAC-activation of the B-cells reduced the response to background levels. No clear dose response was observed and Ig-secreting cells (ISC) could be induced even with rIL2 at 0.5 U/ml. The monoclonal antibody anti-TAC prevented the rIL2-promoted induction of ISC. Ig production could be induced in SAC-activated cultures with supernatants of Xenopus laevis oocytes injected with sucrose-gradient-fractionated poly(A+) RNA derived from a stimulated human spleen cell culture. This activity coincided with the IL2 mRNA activity and was well separated from the interferon-gamma mRNA activity. Our results suggest that IL2 is not only a B-cell growth factor but also promotes the differentiation of activated human B-cells towards Ig secretion.
D000921:Antibody-Producing Cells / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D006462:Hemolytic Plaque Technique; D006801:Humans; D007136:Immunoglobulins / Q000096:biosynthesis*; D066298:In Vitro Techniques; D007376:Interleukin-2 / Q000276:immunology*; D008213:Lymphocyte Activation; D013211:Staphylococcus aureus / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology
D007136:Immunoglobulins; D007376:Interleukin-2