Modulation of Cell Proliferation by Macrophages: A Possible Function Apart from Cytotoxic Tumour Rejection

Abstract

Summary.-The in vitro interaction between activated, non-immune macrophages (AM) and a variety of syngeneic, allogeneic or xenogeneic " normal " and " malignant" target cell lines was followed by different parameters such as target cell proliferation, viability or morphology.Proliferation

Comparison of three isotope-release assays for spontaneous cytotoxicity of macrophages

“…Tests were performed in triplicate and percentage isotope release was determined as previously described (Keller, 1976b(Keller, , 1978. It is noteworthy that viability (assessed by trypanblue exclusion and residual cloning efficiency; Keller, 1974) and replication rate (assessed by cell counts and pulse-labelling with [3H]-TdR; Keller, 1974) ofthe various target-cell types (Tables I and II) was neither affected by isotope labelling nor by the presence of cold TdR (10 -6M) and/or proline (23 mg/l) in the post-labelling phase. Moreover, autologous controls gave isotope release similar to or lower than mediium control.…”

Macrophage-mediated natrual cytotoxicity against various target cells in vitro. I. Macrophages from diverse anatomical sites and different strains of rats and mice

“…Nonadherent, nonphagocytic radio-resistant "natural killer" (NK) cells, distinct from mature T and B cells, and found predominantly in the peripheral blood and spleen of rodents and man, have selective cytotoxicity for a limited range of target cells (Haller et al, 1977;Herberman et al, 1975: Kiessling et al, 1975Shellam, 1977;Shellam and Hogg, 1977;Nunn, Herberman and Holden, 1978). In mice, adherent nonphagocytic peritoneal cells exhibiting spontaneous antitumour cytotoxicity have been reported (Nathan, Hill and Terry, 1976) probably representing a subpopulation of B lymphocytes (Nathan, Asofsky and Terry, 1977 Target cells Early passages of DA rat embryonic fibroblasts (Keller, 1976b), DA rat dimethylbenz-(a)anthracene-induced ascites tumour cells (Keller, 1977a), polyoma-virus-induced tumours (Keller, 1973), early passages of epidermal cells from the skin of normal BALB/c mice (Keller, 1977h), DBA/2 murine mastocytoma P815 (Keller, 1976b) SY740-transformed mouse macrophages (Keller, 1977b) RPMI 7932 human melanoma cells (Keller, 1976b) and the Burkitt's lymphoma cell line RAJI (Keller, 1976b) (Keller, 1974(Keller, , 1976a FCS. After appropriate-macrophage-targetcell interaction, radioactivity was measured in sediments and supernatants as described by Keller (1976c), and the cytotoxicity calculated by the following formula:…”

The cytostatic activity of cultured Kupffer cells

“…The ability of allogeneic macrophages from other sites to exhibit cytostasis has previously been shown in the mouse (Hogg & Balkwill, 1981) and the rat (Keller, 1974(Keller, , 1978.…”