Macrophage-Like Properties of Some Guinea-Pig Transformed Cells

Abstract

Studies were made on guinea pig transformed cells which appear in 90 hr control and mixed lymphocyte tissue cultures. Morphologically the transformed cells resembled human transformed cells, and some of them also contained extensive granulation. Some of the transformed cells showed phagocytic activity and went down on glass like macrophages. Although the transformed cells all appeared morphologically similar, some (especially those going down on the glass) took up cytophilic guinea pig anti-sheep red cell antibodies and became passively sensitized while others did not. Because cytophilic antibody in the guinea pig is passively absorbed only by macrophages and monocytes this evidence points to the acquisition of macrophage properties by guinea pig transformed cells. In turn this is a further piece of evidence supporting a lymphocyte to macrophage transformation in vitro, and thus possibly also in vivo. The significance of this transformation in cellular immunology is briefly discussed.