[Quantitative determination of proteins in the contents of pseudocysts of the maxillary sinus].

The factors C 3c and C 4 of the complement system, the protease inhibitor alpha-1-antitrypsin (AAT) as well as the immunoglobulins IgA, IgG, IgM in the fluid of cysts of maxillary sinus were determined by means of single radial immunodiffusion. The concentration of these proteins was compared with the concentration in the serum obtained simultaneously. A decrease of C 3c, C 4 and AAT and an increase of IgA and IgG in fluid are indicators of active participation of the mucosa in defence processes.