Expression of DR antigens on early human progenitors of neutrophilic and eosinophilic colonies in diffusion chambers (CFUd).

Abstract

Incubation of the non-adherent low density cells from normal human bone marrow with an antiserum to DR antigens markedly inhibited their capacity to form granulocytic colonies in fibrin clot diffusion chambers implanted intraperitoneally into irradiated mice. The inhibitory effect of antiserum was abrogated after absorption of antiserum with B cells. Inhibition was obtained both with and without complement treatment. Neutrophilic colony formation exhibited a higher sensitivity to diluted antiserum to DR antigens as compared with eosinophilic colony formation. These results suggest that DR determinants are expressed on the neutrophilic and eosinophilic progenitor cells (CFUd) which give rise to colonies in diffusion chambers.