Insulin-like Growth Factor-I Unresponsiveness in an Efe Pygmy

Autor: Geffner, M.E., Bailey, R.C., Bersch, N., Vera, J.C., Golde, D.W.
Zdroj: Biochemical and Biophysical Research Communications; June 1993, Vol. 193 Issue: 3 p1216-1223, 8p
Abstrakt: The cause of short stature in African Pygmies is unknown, but some evidence suggests that they are GH resistant. Since IGF-I mediates many actions of GH, we sought to determine if Pygmy tissue is responsive to IGF-I. We established HTLV-II-transformed cell lines from 1 Efe Pygmy, 1 African control, and 3 American controls, and quantified in vitrocolony formation in response to IGF-I, GH, and insulin, and assessed IGF-I receptor binding. The Pygmy T-cell line showed no clonal responsiveness following stimulation with physiologic concentrations of IGF-I or any concentration of OH, but responded normally to insulin. IGF-I binding studies showed no binding to the Pygmy T-cell line with normal binding to control cells. The primary abnormality in this Pygmy T-cell line is IGF-I resistance at the receptor level with secondary OH resistance.
Databáze: Supplemental Index