title: Modulation of EL-4 mouse lymphoma cell proliferation by macrophages and tumor related factors.
abstract: It is well known that macrophages play an important role in the control of tumor growth. This control may be the result of a direct action of macrophages or mediated by several biologically active products or factors elaborated by these and other cell populations. Our studies on the proliferation of a murine T-cell lymphoma (EL-4) showed that the treatment of the ascitic fluid (from the peritoneum of EL-4 bearing mice) with carbonyl iron resulted in a depletion of phagocytes concomitant with a significant increase of [3H] thymidine uptake by EL-4 cells. Further, the growth of EL-4 cells cultured in semisolid agar was significantly inhibited by an underlayer of large quantities of macrophages both from normal and EL-4 bearing mice as well as when cultured in the presence of PGE2. The underlayer of tumor macrophages P388 D1 resulted in an increase of the EL-4 cell growth. Also, conditioned media obtained from in vitro liquid cultures of EL-4 cells and L 1210 cells (B-lymphoma) produced a remarkable inhibition of the in vitro cloning capacity and [3H] thymidine uptake by EL-4 cells. These data support the hypothesis that different factors from normal and hemopoietic tumor cells may control the tumor growth and point out that self-produced factors may modulate the proliferation of tumor cells.
mesh_terms: D000818:Animals; D002450:Cell Communication; D002455:Cell Division; D002478:Cells, Cultured; D003470:Culture Media; D015232:Dinoprostone; D005260:Female; D006801:Humans; D008223:Lymphoma / Q000503:physiopathology*; D008264:Macrophages / Q000502:physiology; D051379:Mice; D009374:Neoplasms, Experimental / Q000503:physiopathology; D010586:Phagocytes; D011458:Prostaglandins E / Q000494:pharmacology; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects; D013936:Thymidine / Q000378:metabolism; D014316:Tritium
chemical_list: D003470:Culture Media; D011458:Prostaglandins E; D014316:Tritium; D015232:Dinoprostone; D013936:Thymidine