Age-related changes in humoral and cell-mediated immunity in down syndrome children living at home

Abstract

Abnormalities of humoral and cell-mediated immunity have been described in Down syndrome but reported findings have been inconsistent. Confounding fac­tors have included age, institutional versus home life, hep­atitis B antigenemia, and zinc deficiency. To clarify this problem, we studied 64 children with Down syndrome (DS) compared with an age-matched control group. All children had always lived at home. All the DS children were nega­tive for hepatitis B surface antigen. Serum zinc concentra­tion in the DS group was on average 12 μg/dl lower than age-matched control children. They also had significantly lower levels of immunoglobulin M, total lymphocyte count, T and B lymphocytes, and T helper and suppressor cells. In vitro lymphocyte response to phytohemagglutinin and concanavalin A was significantly reduced at all ages in the DS group. Lymphocyte response to pokeweed mitogen increased with age in control children but decreased in the DS children. By 18 yr, the mean response for DS was 60000 cpm lower than controls. The DS group had signif­icantly higher concentrations of immunoglobulins A and G than controls and the difference increased with age. Com­plement fractions C3 and C4 were also higher in the DS group at all ages. The number of HNK-1 positive cells was higher in the DS group than controls at all ages. When hepatitis and institutionalization are excluded as confound­ing factors, DS children still differ in both humoral and cell-mediated immunity from an age-matched control group. © 1987 International Pediatric Research Foundation, Inc.