Spontaneously formed tumorigenic hybrids of Meth A sarcoma cells and macrophages in vivo.
We have recently demonstrated that malignant cells can hybridize with tissue macrophages in vitro, giving rise to tumorigenic hybrids. We now demonstrate that this can occur spontaneously in vivo as a result of fusion between inoculated Meth A sarcoma cells and host cells, presumably macrophages. Thus, from tumor cell suspensions prepared by collagenase perfusion and density centrifugation, hybrid cells could be isolated that were neoplastic but in contrast to Meth A expressed macrophage markers and had phagocytic capacity. Their morphologic features were intermediate between Meth A and macrophages. By taking advantage of a semiallogeneic experimental system by inoculation of Meth A cells from BALB/c (H-2 K(d)) into (BALB.K x BALB/c) F(1) (H-2(k/d)), hybrid cells from these tumors could be shown to express MHC antigens of both the Meth A and the host haplotypes. Hybrid cells grew faster than Meth A cells in vivo, indicating acquisition of growth-promoting properties through heterotypic cell fusion.
Busund
Lill-Tove R
LT
Department of Morphology, Institute of Medical Biology, University of Tromsø, Tromsø, Norway. lill.busund@unn.no
Killie
Mette K
MK
Bartnes
Kristian
K
Seljelid
Rolf
R
D000818:Animals; D014408:Biomarkers, Tumor / Q000032:analysis; D002455:Cell Division; D002875:Chromosomes / Q000235:genetics; D005260:Female; D006822:Hybrid Cells / Q000473:pathology*; D008264:Macrophages / Q000473:pathology*; D008748:Methylcholanthrene; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008855:Microscopy, Electron, Scanning; D010587:Phagocytosis; D012513:Sarcoma, Experimental / Q000139:chemically induced / Q000473:pathology* / Q000648:ultrastructure; D014184:Transplantation, Homologous; D014407:Tumor Cells, Cultured
D014408:Biomarkers, Tumor; D008748:Methylcholanthrene