Ultrastructural Analysis of Hemolysin-Forming Cell Clusters

Abstract

Abstract Following in vitro stimulation of mouse spleen cells with sheep red blood cell antigens (SRBC) many of the resulting hemolysin-forming cells have been found to be associated with cell clusters (1, 2). We have initiated a series of studies designed to investigate the interrelationships of the various cell types found within these clusters. We report here preliminary morphologic observations of hemolysin-forming cell clusters. Dissociated mouse spleen cells were cultured in the presence of SRBC using Saunders' (3) modification of Marbrook's (4) technique. After 48 hr of incubation, the spleen cells were carefully recovered and transferred into 15-ml centrifuge tubes which were then placed in an icebucket. Cell clusters were allowed to settle out in the cold for 10 min. The supernatant containing the remainder of the cells and medium was discarded. The recovered cell clusters were analyzed for hemolytic activity by the method of Jerne and Nordin (5).