[Cellular immunity in cigarette smokers]

T-lymphocyte counts have been measured and the skin test with amnestic antigens performed in 85 clinically healthy men aged 18-42 (the mean age 34) smoking 15-25 cigarettes daily during 2-25 years and in a reference group of 49 non-smokers aged 17-50 (the mean age 31). The absolute count of circulating lymphocytes has been found increased in 38 subjects who smoked for up to 10 years (the mean period 6.5 years), whereas in the subjects who smoked for more than 10 years (the mean period 18.5 years) the absolute and the relative counts of T-lymphocytes have been decreased, the tuberculin test has been much more often negative (14.9% vs. 6.1 and 5.3%), as well as the distreptase test (19.1% vs. 8.2 and 5.3%). These data confirm the suppressor effect of tobacco smoke, inhaled for a long time, on cell-mediated immunity in humans.