Enhanced immune system regeneration in humans following allogeneic or autologous hemopoietic stem cell transplantation by temporary sex steroid blockade.

Purpose: To determine if temporarily blocking sex steroids prior to stem cell transplantation can increase thymus function and thus enhance the rate of T cell regeneration.

Experimental Design: This was a pilot study of luteinizing hormone-releasing hormone agonist (LHRH-A) goserelin given 3 weeks prior to allogeneic or autologous hemopoietic stem cell transplantation and administered up to 3 months posttransplantation. Patients (with or without LHRH-A administration) were assessed from 1 week to 12 months posttransplantation for multiple immunologic variables by flow cytometry (particularly naïve T cells), quantitative PCR to assess T-cell receptor excision circle levels (as a correlate of thymus function), CDR3 length analysis to determine the variability of the TCR repertoire, and in vitro assays to determine functional T cell responses.