IgA paraprotein inhibition of human neutrophil chemotaxis. Reduced activity following treatment with IgA-specific protease from Neisseria gonorrhoeae.

Removal of the Fc region of human IgA m components by treatment with IgA-specific protease from Neisseria gonorrhoeae reduces the neutrophil chemotactic inhibitory activity associated with IgA M components. This observation, along with the failure of an IgA halfmer paraprotein to inhibit neutrophil chemotaxis, emphasizes the importance of the IgA Fc region in the inhibition of neutrophil chemotaxis by IgA M components.