We report the fractionation of freshly isolated subsets of tonsillar lymphocytes according to cell density and double sorting for the differential expression of CD10 and CD77, and their analysis for the presence of Epstein Barr virus genome by nested PCR. All the subsets of tonsillar lymphocytes gave unequivocal evidence for the presence of EBV DNA, when obtained from EBV seropositive individuals. Confirmation of all cases examined demonstrates that B lymphocytes from the germinal centers of tonsils are also involved in carrying the EBV infection in vivo.