Simple assay method for susceptibility of human lymphocytes to Epstein-Barr virus infection

On the basis of the sequential early events induced by Epstein-Barr virus (EBV), the infectivity of human lymphocytes to EBV was quantified as a plateau value of the maximum nuclear antigen (EBNA) synthesis preceding cellular DNA synthesis. The frequency of EBV-infectible cells was an average of 7.6% of unfractionated umbilical cord lymphocytes and was 4.9% in the counterparts from human adults. In the B-cell-enriched populations, the average plateau values were 29.2% in umbilical cord and 15.5% in adult samples. This method is simple and applicable for quantitative assay of the sensitivity to EBV infection of a given lymphocyte preparation.