[GH-dependency of lymphocyte multiplication factor with a low molecular weight]

Liquid chromatography (FPLC) separation at pH 6.85 shows that the fractions in human serum which stimulate the multiplication of human lymphocyte are mainly in the 28-42 kd and the 1.3-1.9 kd fractions. The low molecular weight fraction is absent or very low in both GH-deficient and GH-resistant children and T lymphocyte-deficient children, and appears after appropriate treatment, i.e. GH or marrow transplantation. The data suggest the GH-dependency of 1.3-1.9 kd factor(s) produced by immuno-competent lymphocytes.