In vitro production of granulocyte–macrophage colony‐stimulating activity by murine bone marrow and spleen following vinblastine administration IN VIVO

Abstract

The production of granulocyte-macrophage colony-stimulating activity (CSA) by isolated murine femur shafts, non-dispersed bone marrow and spleens was assessed following administration of Vinblastine (VLB). These organs were removed from 2 h to 10 days post-VLB and allowed to condition endotoxin-free medium for 48 h. CSA activity was assessed using a soft agar cloning system. The data demonstrate that CSA elaboration was maximal 24 h post-VLB, corresponding to the nadir of bone marrow GM-CFC, and 6 h after splenic reached a minimum. No relationship between peripheral blood granulocyte count or serum endotoxin levels were observed.