In Vitro Evaluation of Cell-Mediated Immunity to Epstein Barr Virus

This study was conducted to measure cell-mediated immune response in healthyepstein barr virus (ebv)–seropositive individuals using a tissue culture growthinhibition assay (regression assay) where peripheral blood lymphocytes (pbls) weretested for their ability to inhibit the outgrowth of the autologous lymphoblastoid celllines (lcls). inhibition of the outgrowth of the autologous lcls was seen after 4weeks by the addition of pbls from healthy ebv seropositive donors. the regressionphenomenon was never seen when the donors of peripheral blood lymphocytes wereebv- seronegative. regression assay showed that ebv- specific memory t cells werestable in healthy ebv seropositive over many years, which indicates the persistentnature of ebv infection.