Formation of colonies of clonogenic stromal precursors in bone marrow and splenic cell cultures in the presence of streptococcal antigens in the culture medium

The presence of streptococcal M protein and A polysaccharide in culture medium is shown to have an inhibitory effect on the growth of clonogenic stromal precursors in cultures of healthy murine bone marrow and of healthy guinea pig bone marrow and spleen. The efficacy of colony formation dropped 1.5- to 2-fold in the presence of antigens in a concentration of 25 μg/ml in the medium. The inhibitory effect was absent if antigens were added to adhesive cell cultures. The addition of antigens to cultures originating from animals immunized with streptococcus resulted in inhibition of the efficacy of colony formation in complete cultures and in cultures of adhesive cells. The presence of streptococcal antigens in guinea pig stromal fibroblast cultures of different strains did not affect their growth or colony formation. These data indicate that the effects of streptococcal antigens appear to be aimed at the stromal cells not directly, but rather via another cellular category in the bone marrow and splenic cell cultures, probably lymphocytes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 11, pp. 489–492, November, 1994