HUMAN T-CELL HYBRIDOMA FORMATION FOR POTENTIAL PRODUCTION OF TRANSFER FACTOR

Abstract

Peripheral blood mononuclear cells from individuals with exquisite cell-mediated immunity (CMI) to the recall antigens PPD,Diphtheria Toxoid (DT), Tetanus Toxoid (TT), or Candida (CAN) were stimulated with that antigen for 5-7 days and then subsequently fused to either of 2 HAT sensitive human T-cell Leukemia cell lines (BUC or F-353)^*. These cell lines demonstrate a helper T-cell phenotype but are OKT3 negative. T-cell hybridomas were selected for in HAT containing media. Resultant clones were sub-cloned by limiting dilution. Transfer Factor (TF) was prepared from individual clones and tested for in vitro inducer of CMI activity and suppressor of CMI activity in a Leukocyte Migration Inhibition (LMI) assay. TF from an (OKT3⁻) clone derived from a PPD positive individual exhibited inducer activity specific for PPD but not for TT. TF prepared from the parent BUC line showed no inducer activity. Another clone derived from a fusion of a DT immune donor and the BUC line was shown to possess DT inducer activity in the LMI assay. This clone demonstrated the OKT3 marker on 12-18% of its cells. TF production by both DT and PPD hybrids was short-lived. Several hybrids were derived from a TT immune individual. Four clones derived from these hybrids acquired OKT3 markers. TF from two of these demonstrated TT inducer activty. This activity was lost following immunoabsorption of the TF on TT, a finding consistent with the ability of human TF to bind to specific antigen.