[T-lymphocyte precursors--the target cells of thymocyte growth factor]

The cortisol-resistant PNA+SC- --1+Thy--1+-thymocytes are the target cells for the thymocyte growth factor (THGF), which is produced by the lines of transformed precursors of T-lymphocytes (PTL). These cells have the same properties and markers as the intrathymic PTL. The bone marrow cells do not proliferate in response to THGF but acquire that ability after the influence of thymic hormones, which induce the maturation of PTL. Thus, THGF is the autocrine growth factor of intrathymic PTL.