title: Purification and characterization of erythrogenic toxins. IV. Communication: mitogenic activity of erythrogenic toxin produced by Streptococcus pyogenes strain NY-5.
abstract: Some in vitro reactions involved in the mitogenic activity of a purified erythrogenic toxin from the group A streptococcus strain NY-5 (ET NY-5) were studied. The optimal dose in the human blood lymphocyte transformation test was 1 to 10(-1) microgram/ml lymphocyte culture, the maximum of 3H-thymidine incorporation was on day 3 or 4. The mitogenic activity showed the signs of nonspecificity, nevertheless, a specific mitogenic effect could not be ruled out either. When Con A and ET NY-5 were added simultaneously in high or low doses at the beginning of lymphocyte cultivation, antagonism or an additive effect was observed, respectively. Incubation of lymphocytes with ET NY-5 resulted in a decrease of mitogenic activity in the supernatants. Erythrocytes had no similar binding activity. ET NY-5 acts as a T-cell mitogen; 98% of ET NY-5-stimulated lymphoblasts formed E rosettes with sheep red blood cells. Thin-layer isoelectric focusing experiments revealed two mitogenic peaks corresponding to toxin types A and C in the ET preparation.
mesh_terms: D001426:Bacterial Proteins; D001427:Bacterial Toxins / Q000302:isolation & purification / Q000494:pharmacology*; D003208:Concanavalin A / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005098:Exotoxins; D006801:Humans; D007525:Isoelectric Focusing; D008213:Lymphocyte Activation; D008565:Membrane Proteins; D008934:Mitogens / Q000494:pharmacology*; D013297:Streptococcus pyogenes; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D005098:Exotoxins; D008565:Membrane Proteins; D008934:Mitogens; C117980:SpeA protein, Streptococcus pyogenes; C027951:erythrogenic toxin; D003208:Concanavalin A