Peritoneal exudate cells II. Kinetics of appearance of colony‐forming cells

A transient increase in the number of peritoneal colony‐forming cells in agar (PCFC) was noted in the peritoneal cavity of mice given one intraperitoneal injection of thioglycollate medium. This increase of PCFC was not accompanied by a similar degree of increase in the number of either pluripotent hemopoietic stem cells or committed hemopoietic stem cells for granulocytes and/or macrophages that are normally present in the peritoneal cavity in small numbers. Other substances, such as glycogen, starch, Freund's adjuvant, sheep red blood cells and lectins, were also capable of increasing PCFC, but to different degrees. The ability of thioglycollate medium as well as other stimulatory agents to increase PCFC appeared to be dose‐dependent.