Antigen uptake in vivo by peritoneal macrophages from mice exhibiting antigenic competition

The in vivo uptake of human serum albumin and ferritin by peritoneal macrophages has been studied. Peritoneal macrophages were obtained from normal mice, mice undergoing primary and secondary responses and mice exhibiting serological evidence of antigenic competition. The antigens were conjugated with two different fluorochromes and traced by fluorescence microscopy. Both antigens were ingested concurrently by the macrophages regardless of the immunological state of the mice.