Intralymphnode injection of human monocyte macrophage colony stimulating factor (CSF-1) as a method of obtaining high titer anti-CSF-1 antibodies.

We describe a rabbit intralymphnode immunization technique for obtaining a high titer antihuman CSF-1 antiserum with small amounts of antigen. This procedure provided a rapid (42 days after primo-injection), stable maximum immune response with a high titer antiserum precipitating 30% of 125I CSF-1 at a 1:25.000 dilution. The specificity of the immune serum was assessed by competitive binding experiments in RIA and neutralization of the CSF-1 biological activity in culture. The antiserum was also tested for its ability to detect CSF-1 in Western blotting, immunocytochemistry and immunohisto-chemistry. The results show that the immune serum specifically recognizes the biological active domain of human CSF-1 molecules from different origins and only detects dimeric forms. The potential uses of this anti CSF-1 antiserum are discussed.