Fusion of hamster macrophages induced by lectins

The fusion of hamster peritoneal macrophages by lectins is described. The conditions under which this occurs are very similar to those previously reported using glutaraldehyde-fixed red cells and anti-hamster macrophage serum. Under conditions in which macrophages are brought into contact before interiorisation of surface-bound lectin, fusion results. It is suggested again that in granulomas, binding of endocytosable material to more than one macrophage results in giant cell formation by a mechanism of simultaneous interiorisation.