Benzo pyrene immunosuppression

There is evidence for immunosuppressive effects of PAHs in rodents (Davila et al. 1997). For example, strong immunosuppressive effects were reported in mice that had been dosed with benzo[fl]pyrene and 3-methyl cholanthrene, effects that persisted for up to 18 months (Environmental Health Criteria 202). Multiple immu-notoxic effects have been reported in rodents, and there is evidence that these result from disturbance of calcium homeostasis (Davila et al. 1997). PAHs can activate protein tyrosine kinases in T cells that initiate the activation of a form of phospholipase C. Consequently, release of inositol triphosphate—a molecule that immobilizes Ca + from storage pools in the endoplasmic reticulum—is enhanced. 

Carlson, E.A., Y. Li and J.T. Zelikoff. The lapanese medaka (Oryzias latipes) model applicability for investigating immunosuppressive effects of the aquatic pollutant benzo[a]pyrene (BaP). Mar. Environ. Res. 54 565-568, 2002. 

Benzo[a]pyrene is a potential immunosuppressant. The action is caused by death, leading to a reduction of the immune cells number. BaP has been shown to cause cell death in lymphocytes [33], macrophages [15,92], monocytes [94] and bone marrow eells [104]. Macrophages are the cell type that can metabolize BaP to BPDE [49], Thus, production of BPDE caused macrophage cell death and reduce phagocytic activity. 

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