Differential response of T cells to an immunogen, a mitogen and a chemical carcinogen in a mouse model system.

In this study, we examined the relative immune response of T-lymphocytes and its intracellular cholesterol homeostasis, in a mouse model system, after treatment with immunogen, mitogen, and carcinogen. We studied the T-lymphocyte percentage, their LDL-receptor expression, along with the levels of serum interleukins (IL-2, IFNγ, IL-4, and IL-10) and intracellular cholesterol concentration (cytoplasmic and nuclear). The mitogen was found to be a better stimulator of T-cell marker expressions than the immunogen; though the immunogen was more effective on immunogenic response as was marked from interleukin levels. The chemical carcinogen benzo-α-pyrene at low concentration acted potentially like a mitogen but a reduced immune response was apparent at a carcinogenic dose. The findings in our study focus on the effect of carcinogenic dose of benzo-α-pyrene (BaP) on T-cell immunity. Benzo-α-pyrene causes immunosuppression through restriction of the T-cell population by targeting intracellular cholesterol.