ACCELERATED EXPANSION OF EXTRATHYMIC T-CELLS IN THE LIVER AND OTHER ATHEROSCLEROTIC LESIONS IN MICE FED WITH ATHEROGENIC DIETS

Immunoparameters in mice fed with atherogenic diets for 4 months were examined. In parallel with accelerated thymic involution, a prominent increase in the proportion of IL-2R beta(+) intermediate TCR cells (i. e., extrathymic T cells) was seen in the liver and other immune organs of mice with atherosclerosis. In contrast, NK cells and high TCR cell s (i.e., conventional T cells of thymic origin) decreased. The majorit y of mononuclear cells isolated from the aorta and kidneys in these mi ce were also found to be intermediate TCR cells. The present results s uggest that mice with atherosclerosis have an accelerated pattern of a ging of the immune system and that extrathymic T cells may be responsi ble for the formation of atheroscherotic lesions.