Serological, immunochemical and immuoncytological properties of granulocyte antibodies.

The immunochemical characteristics of granulocyte allo- and autoantibodies can easily be studied with indirect immunofluorescence techniques. The correlation of these properties with the serological behavior of the antibodies and the clinical condition in which they were found was studied. The investigations included the determination of immunoglobulin class, subclass, light-chain composition, as well as optimal temperature of activity. Complement fixation in vitro was also investigated. Striking differences were found between IgG and IgM antibodies in their serological properties, especially in the granulocytotoxicity and leukoagglutination tests at different temperatures. Differences in light-chain and IgG subclass compositions of the antibodies did not seem to play a role. In studying the distribution of granulocyte-specific antigens on normal granulocytes and granulocytes in all stages of development, it was found that, while NA1, NA2 and ND1 are present in the same quantity on the cells of an individual, the NB1 antigen is unequally distributed, both over ripe granulocytes and granulocyte precursors.