Immunoglobulin production in man stimulated by an orally administered bacterial lysate.

The concentrations of secretory immunoglobulins in the saliva, and of immunoglobulin in the serum, have been measured by the radial immunodiffusion method in 12 healthy volunteers, before and after oral administration of Broncho-Vaxom which is a lysate of bacteria that usually cause infection in the upper respiratory tract. The mean concentration of secretory IgA in the saliva was increased by over 100% after the 10-day administration of the product. This increase was statistically significant between the 20th and 33rd day after the beginning of the treatment (p < 0.05). It fell to a normal level after a month in 4 subjects who received one treatment course only. In 8 subjects who received a second treatment course beginning 1 month after termination of the first course, the high concentration of IgAs in the saliva persisted for at least 3 months. A significant increase in the serum concentrations of IgG of about 50% and of IgM of at least 100% above the initial level was observed in the treated subjects in the time between day 35 and 5 months after the beginning of the experiment (p < 0.05).