Regulation of human blood erythroid burst-forming unit (BFU-E) proliferation by T-lymphocyte subpopulations defined by Fc receptors and monoclonal antibodies

To determine whether normal T-cell subpopulations influence human blood BFU-E proliferation variably, sheep erythrocyte rosettable cells (unseparated T cells) were fractionated into subpopulations based on their differential binding to IgM (Tμ cells) or IgG-coated ox erythrocytes (Tγ cells). For comparative purposes, T cells, Tγ cells, and T cells depleted of Tγ cells (T-non-γ cells) were further characterized by their reaction with the OK panel of monoclonal antibodies (OKT3, OKT4, OKT8, OKM1). Quantities of 2.0 × 105 Tμ, Tγ, or T-non-γ cells were mixed with 2.0 × 106 autologous BFU-E-enriched null cells in a methyl-cellulose culture system with 2.0 IU erythropoietin. Tμ cells or T-non-γ cells consistently increased BFU-E numbers above that observed with either unseparated T cells or Tγ cells (p