Immune response cannabis

The presence of cannabinoid receptors in the immune system has led to consideration of the effects of cannabis on its function. Cannabinoid receptors have been found in spleen cells (Kaminski et al. 1992). Activation of these receptors would inhibit their function in the immune response. Similar suppressant effects occur on lymphocytes (Diaz et al. 1993). THC and anandamide inhibit macrophage-mediated tumor necrosis (Cabral et al. 1995). Despite these effects, their functional significance remains to be determined. These effects are most likely subtle. 

The effects of marijuana on immune function have been reviewed (122). The studies suggest that marijuana affects immune cell function of T and B lymphocytes, natural killer cells, and macrophages. In addition, cannabis appears to modulate host resistance, especially the secondary immune response to various infectious agents, both viral and bacterial. Lastly, marijuana may also affect the cytokine network, influencing the production and function of acute-phase and immune cytokines and modulating network cells, such as macrophages and T helper cells. Under some conditions, marijuana may be immunomodulatory and promote disease. 

Cannabinoids are able to cause different effects at the level of various systems and/or organs the most important effects occur on the central nervous system and on the cardiovascular system. In fact, they are able to affect mood, memory, motor coordination and cognition, and they increase heart rate and variate the systemic arterial pressure. Furthermore, it is well known the capability of cannabinoids to reduce intraocular pressure and to affect the respiratory and endocrine systems (L. E. Hollister, Health Aspects of Cannabis, Pharmacological Reviews, 38,1-20,1986). More recently, it was found that they suppress the cellular and humoral immune response and have antiinflammatory properties (A. W. Wirth et al.. Antiinflammatory Properties of Cannabichromene, Life Science, 26,1991-1995,1980). 

In animals and man, chronic use often suppresses the immune system s response to inhaled bacterial or fungal material. In this connection it is relevant to note that a contaminant mould (Aspergillus) found in cannabis can predispose immunocompromised cannabis smokers to infection. It has been suggested that baking the cannabis (at 300°F for 15 minutes) before smoking will kill the fungus and reduce the potential risk (121). 

Delta-9-THC is the main active constituent extracted from Cannabis sativa (Tuner, 1985 in Marijuana 1984, Ed. Harvey, DY, IRL Press, Oxford). Numerous articles have described not only psychotropic effects of cannabinoids but also their influence on the immune function [Hollister L. E., J. Psychoact. Drugs 24 (1992) 159-164]. The majority of in vitro studies have shown that cannabinoids have immunosuppressant effects inhibition of the mitogen induced proliferative responses of T lymphocytes and B lymphocytes [Luo, Y. D. et ah, Int. J. Immuno-pharmacol. (1992) 14,49-56 Schwartz, H. et at., J. Neuroimmunol. (1994) 55,107-115], inhibition of the activity of cytotoxic T cells [Klein et at., J. Toxicol. Environ. Health (1991) 32, 465-477], inhibition of the microbicidal activity of macrophages and of TNF-a synthesis [Arata, S. et at.. Life Sci. (1991) 49, 473-479 Fisher-Stenger et al., J. Pharm. Exp. Then (1993) 267, 1558-1565] and inhibition of the cytolytic activity and the TNFa production of large granular lymphoc3rtes [Kusher et al.. Cell. Immun. (1994) 154, 99-108],... 

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