[Mechanism of action of secretory IgA antibodies].

The antiadsorptive capacity of secretory IgA to Sh. sonnei was revealed in experiments with Shigella keratoconjunctivitis used as a model. In patients with dysentery caused by Sh. sonnei IgA in coprofiltrates proved to have greater capacity for agglutinating the antigen than serum IgA. The presence of IgA as coproantibodies in these patients sharply decreased the frequency of diagnostic seroconversions. The importance of the above-mentioned properties of SIgA for diagnosis and for protection from infections affecting the organs and tissue coming into contact with the environment are discussed.