Isolation and characterization of lectin-resistant mouse cell lines defective in their ability to yield hybrid cells

Lectin-resistant variants of the mouse mammary tumor cell line FM3A in suspension were isolated after multiple-step selection using toxic concentrations of phytohemagglutinin (PHA) and concanavalin A (Con A). In fusion experiments, both PHA- and Con A-resistant lines were found to have lost the ability to yield hybrids with suspension-grown cells, although they were capable of yielding hybrids with monolayer-grown cells. This phenotype of PHA-resistant lines was stable during a long period of culture in the absence of PHA.