Exudation of proliferative macrophages in local inflammation in the peritoneum

phages (ms) were highly proliferative and formed m colonies in vitro in the presence of m4 colony-stimulating factor (M-CSF), while resident peritoneal m4s did not. To determine whether such proliferative m4s are im-migrant or locally activated resident ms, mice depleted of bone marrow cells and circulating monocytes by bone-seeking radiostrontium (89Sr) were injected intraperi-toneally with TG. For control 88Sr) and splenectomized (Spx) mice, more than 4 x 10 m4 colony-forming cells ( M-CFCs) per mouse were recovered in the peritoneal lavage fluid 5 days after TG injection. 895r-treated mice, on the other hand, had only 20 % of those in the control mice. Splenectomized and 895r-treated (Spx/895r) mice showed further depletion of bone marrow cells and mono-cytes and, as expected, total numbers of peritoneal M-CFCs were severely depressed to less than 1 % of those in the control mice. The results suggest that levels of peritoneal M-CFCs are strongly dependent on the presence of radiosensitive bone marrow cells and circulat-ing monocytes, and resident peritoneal ms activated lo-cally by inflammatory stimuli do not form m4 colonies under the defined conditions. j Lcukoc. Biol. 52