Herpesvirus saimiri transformed T cells and peripheral blood mononuclear cells restimulate identical antigen-specific human T cell clones

Panels of human antigen-specific T cell clones (TCC) have been established by limiting dilution using Herpesvirus saimiri (HVS) subtype C transformed T cells as antigen presenting cells (APC). They showed antigen-specific pro liferation when peripheral blood mononuclear cells (PBMC), HVS-transformed T cells and Epstein Parr Virus transformed lymphoblastoid B cell lines (EBV -LCL) were used as APC, All T cell clones were CD4+ and HLA class II restri cted. For a detailed analysis, two panels of T cell clones specific for an epitope located in the N-terminus of the Merozoite Surface Protein 1 (MSP-1 ) of Plasmodium falciparium were established from the same founder T cell l ine using either PBMC or HVS-transformed T cells as APC. TCR analysis of th e two panels of TCC demonstrated that the same founder cells could be propa gated in both culture systems. Furthermore, no difference in the cytokine e xpression pattern or antigen processing and co-stimulatory requirements was observed between TCC established on PBMC or HVS-transformed T cells. Based on the finding that HVS-transformed T cells can replace PBMC as APC for is olation and propagation of antigen-specific TCC, a protocol was developed a nd successfully executed, which allows to establish and maintain vaccine-sp ecific T cell clones from 30 ml of blood. This method might be particularly significant in clinical trials of immune intervention strategies. (C) 2001 Elsevier Science B.V. All rights reserved.