Decreased Levels of Helper T Cells

Abstract

DECREASED maternal immune responsiveness during pregnancy may partly explain the survival of the fetus as an allograft. It may also account for changes in disease activity and antibody production in several autoimmune diseases during pregnancy and in the post-partum period. Previous in vitro studies of cellular immunity in pregnant women have demonstrated decreased lymphocyte responses to phytohemagglutinin,1 to mixed lymphocyte culture,1 and to soluble antigens.2 An increased incidence and severity of certain viral infections has also been observed.1 , 3 An imbalance between helper and suppressor T cells has recently been demonstrated in several autoimmune diseases4 , 5 and in immunodeficiency states,4 in studies . . .