Lymphocytic Subpopulation Profiles in Bronchoalveolar Lavage Fluid and Peripheral Blood From Tobacco and Marijuana Smokers

An abundance of epidemiologic and physiologic data have defined the consequences of tobacco smoking on lung health. Besides being the major determinant in the development of lung cancer and chronic obstructive pulmonary disease, tobacco use appears to increase the susceptibility to and severity of respiratory tract infections. Disorders caused by tobacco use may be the result of several mechanisms, including carcinogenic effects, direct irritation and damage within the respiratory tract, and impairment of local and systemic host defense mechanisms. www.canadian-familypharmacy.com

Marijuana smoking continues to be a common practice among American adults and teenagers. Marijuana smoke contains many of the same toxins and irritants as tobacco smoke, as well as chemicals not found in tobacco, such as 9A-tetrahydrocannab-inol (THC) and other cannabinoid compounds. Whether habitual marijuana use can lead to pulmonary disorders similar to those caused by tobacco smoking remains unknown.
Previous studies have demonstrated a variety of alterations that take place at the cellular level in association with smoking. Accumulation of inflammatory cells in the lower respiratory tract has been reported in both tobacco and marijuana smokers. Other studies have documented local and systemic T-lymphocyte abnormalities in tobacco smokers. Given the similarity of tobacco and marijuana smoke composition, it would be logical to question whether similar immunologic alterations are present in habitual marijuana smokers.
In this study, we compared the composition of bronchoalveolar and peripheral blood lymphocytic phenotypes in heavy, habitual marijuana smokers (MS), tobacco smokers (TS), and smokers of both marijuana and tobacco (MTS). We found distinct differences in the profiles of local and systemic T-lymphocyte populations in marijuana users compared with those of tobacco users.