The use of HLA-A*0201-transfected K562 as standard antigen-presenting cells for CD8+ T lymphocytes in IFN-γ ELISPOT assays

ELISPOT assays are increasingly used for a direct detection and quantification of single antigen-specific T cells in freshly isolated peripheral blood mononuclear cells (PBMC). They are particularly attractive for the monitoring of specific T lymphocyte responses in clinical trials assessing antigen-specific immunizations in patients with cancer or chronic viral infections. However, one major limitation for the broad clinical implementation of ELISPOT assays is the lack of an inexhaustible source of suitable HLA-matched antigen-presenting cells (APC). Currently available allogeneic or xenogeneic APC (such as the human lymphoid hybrid T2 or HLA-transfected insect cells) can either lead to st…