Human Th0-type T helper-cell clone supports antigen-specific immunoglobulin production in scid/beige-hu mice.

Tetanus toxoid-specific T cells have been generated from human splenic lymphocytes by an initial 6-day stimulation period with antigen, followed by a proliferation period with recombinant IL-2 and human feeder cells. Proliferating T cells were subsequently cloned by limiting dilution. A human T-cell clone that was functionally characterized showed: (i) a specific proliferative response to tetanus toxoid in the presence of autologous Epstein-Barr virus (EBV)-transformed lymphoblastoid cells; (ii) a phenotype characteristic for the helper/inducer CD4+/CD8-/CD450R0+ T cells, and (iii) a lymphokine profile, as determined by mRNA analysis, representative of Th0-like human CD4+ T helper cells. This tetanus toxoid-specific T-cell clone which showed antigen-dependent helper activity for antibody production by autologous B cells in vitro could also provide T-cell help to antigen-specific human B cells transplanted into severe combined immunodeficiency (scid/beige) mice.