[Effect of low-molecular substances on E-rosette formation of human lymphocytes in vitro]

The classical characteristics of T lymphocytes to form E rosettes with sheep red blood cells dependents on various endogenous and exogenous factors or substances present in the reaction medium. A concentration dependent inhibition of E rosetting with human lymphocytes in vitro was found after incubation with several drugs and occupational chemicals. A minimum effect was caused by dimethyl sulfoxide, benzene, sodium azide, and urea; a higher one was found with hydroxy derivatives of benzene, formaldehyde and the antiinflammatory drug ZIMET 49/79, whereas the strongest inhibition was effected after incubation with ethanol, the detergents sodium dodecyl sulfate and triton X-100, respectively, and the antipsoriatic drug dithranol (anthralin). The presence of serum proteins (20 per cent inactivated calf serum) reduces these effects.