Lymphotoxin (LT) production by lymphocytes from children with primary immunedeficiency disease

Lymphotoxin (LT) production and [3H]thymidine incorporation by lymphocytes stimulated with phytohemagglutinin (PHA) were studied in 40 children with primary immune deficiency. LT activity was null in lymphocyte supernatants of children with severe combined immune deficiency (SCID). It was often diminished in culture supernatants from children with various other forms of immune deficiencies including common variable hypogammaglobulinemia and Bruton disease. Following thymus or bonemarrow grafting, the capacity to produce LT appeared in SCID but rose more slowly than the proliferative response to mitogens. This together with the observation that LT activity and [3H]thymidine uptake were dissociated in several cases, suggested that these two functions of cell-mediated immunity might be attributable to different T-cell subsets.