[Humoral immunity in smokers]

B-lymphocyte counts, immunoglobulin levels, blood serum antiA and antiB isoagglutinin concentrations and lysozyme activity, and hemolytic activity of the complement were measured in 85 healthy men aged 18 to 42 (mean age 34) smoking 15-25 cigarettes daily for 2-25 years and in a reference group of 49 nonsmokers aged 17 to 50 (mean age 31). Tobacco smoking was found to have no effect on the peripheral blood B lymphocyte count, nor on the blood serum concentrations of group isoagglutinins. In men smoking for 6.5 years on an average the absolute count of lymphocytes was elevated vs. the reference value. In those smoking for 18.5 years on an average IgA, IgG, and lysozyme concentrations were lowered. These results evidence that the mechanism of humoral immunity weakening in tobacco smokers is intricate and related to a deficit of many proteins responsible for immunobiological processes in human body.