Epstein-Barr Virus Genome Carrying Lymphocyte Subpopulations of Human Palatine Tonsils 1

Abstract

Introduction. The human palatine tonsil, a major lymphoid organ of the oropharynx, has Received the focus of attention in relation to EBV localization in the head and neck. Serological studies of Tischendorf (1) first showed a relationship between EBV and heterophil-negative exudative tonsillitis. Later, our laboratory (2) supported and expanded these findings by reporting significant IgM-specific antibody titer changes for EBV occurring in patients with the same disease. Subsequently, Werner (3) experimentally inoculated gibbons intratonsillary with EBV and all animals contracted exudative tonsillitis and sero-converted following incubation. Evidence of the virus, Epstein-Barr nuclear antigen (EBNA), was then found by Veltri et al. (4) in the tonsil lymphocytes of patients with exudative tonsillitis, along with positive serology to EBV, early antigen (EA), and/or virus capsid antigen (VCA). The purpose of this investigation was to confirm the existence of a defined patient sample harboring latent EBV and to define specific subpopulations harboring EBV virus.

Materials and methods. Collection of tonsils. The right and left human palatine tonsils were obtained from 23 patients diagnosed as having recurrent exudative tonsillitis. The patients ranged in age from 4 to 29 years, with the mean age being 12 years. Following tonsillectomy, the tonsils were placed in Hanks' balanced salt solution (HBSS) containing 4 units/ml of heparin, 1000 units/ml of penicillin G, and 1000 μg/ ml of streptomycin and then transported to the laboratory in an ice bath. A serum sample was also obtained at the time of tonsillectomy.

Preparation of tonsil lymphocytes (TL).

The method used for the isolation and purification of TL is a procedure described by Sloyer et al. (5) and modified by Veltri et al. (4).

All 23 tonsils fractionated by this procedure yielded an average cell viability of 93%, as determined by trypan blue dye exclusion. By Wright's staining an average of 97% of the cells in the final TL populations were identified as lymphocytes.