An established feline monocytic cell line.

A feline monocytic cell line was established from a venous blood sample obtained from a healthy male donor cat. The cloned cells, temporarily named FLMo/K02, were successively passaged in vitro with cell growth medium consisting of RPMI-1640 supplemented with 10% heat-inactivated fetal calf serum. Non-specific esterase and acid phosphatase, as marker enzymes, were clearly demonstrated by cytochemical examinations. The cells treated with allogeneic serum for two hours in advance showed enhanced reactivity to monoclonal antibodies, feline CD1a, canine CD11b, feline CD11c, canine CD11d, and feline MHC-II.