STIMULATORY AND INHIBITORY EFFECTS OF CYCLIC-AMP ON LYMPHOCYTES FROM ATOPIC CHILDREN

The effect of cholera toxin and dibutyryl cAMP on mitogen-activated lymphocytes from atopic and non-atopic individuals was studied. Cholera toxin enhanced stimulation by phytohemagglutinin of cells from small children but not from adults. Dibutyryl cAMP at low concentration (< 10-5M) significantly enhanced the lymphocyte response to mitogens in some, but not all individuals. High concentrations, on the other hand, were consistently inhibitory. In atopic children, the lymphocyte response to T cell mitogen was Significantly less stimulated by cholera toxin, and more inhibited by dibutyryl cAMP than the response of cells from non-atopic matched controls. Thus, T cells from atopic individuals appear to have an altered sensitivity to the action of cAMP. possibly resulting in an impaired balance between helper and suppressor T cells. The hypothesis is advanced, that such an altered balance is causally related to hyperproduction of IgE resulting in atopic disease. © 1979 S. Karger AG, Basel.