RESUMEN
During 20 years different oral immunostimulators have been developed and tested in the National Center of Infectious and Parasitic Diseases in Sofia, Bulgaria. Some of them are widely and quite successfully used in clinical practice for immunotherapy and immunoprophxis (Respivax, Urostim, Dentavax). Data on the immunostimulating activity of polybacterial immunostimulants are presented. Numerous clinical investigations, including double-blind studies, have convincingly demonstrated their high efficacy in the prevention and treatment of non-specific infections of the respiratory organs, the urogenital tract, the oral mucosa and periodontium, as well as in the complex therapy of AIDS. All these facts suggest that immunostimulators, in particular polybacterial ones, are a highly promising tool of modern immunotherapy and immunoprophylaxis aimed at the beneficial modulation of immune response in humans.