Prolonged impairment of cellular immunity in children with intrauterine growth retardation.

Cellular immunity was studied in 17 newborn infants, in eight children aged 1 to 5 years with intrauterine growth retardation, and in age-matched control subjects. At birth T and B peripheral blood lymphocytes were decreased, and delayed cutaneous hypersensitivity to phytohemagglutinin was diminished. In vitro PHA-induced lymphocyte proliferation was similar to that in control subjects but was greater than in healthy adults. In later childhood the numbers of T lymphocytes were normal, but their proliferative capacity was significantly reduced and cutaneous hypersensitivity was minimal or absent. Prolonged impairment of cellular immunity in these children may explain their increased susceptibility to infection and inadequate response to immunization, and predispose to the development of allergic, autoimmune, and neoplastic disease.