TISSUE DISTRIBUTION OF EPSTEIN-BARR-VIRUS GENOTYPES IN HOSTS COINFECTED BY HIV

Background: In healthy people, oral and pharyngeal epithelium preferen tially carries Epstein-Barr virus (EBV) belonging to a genotype that p ossesses three copies of a 29 base-pair repeat in the first intron of the BZLF-1 gene, while peripheral blood mostly carries a genotype that bears two copies. Whether EBV shows differential tropism in HIV-1-coi nfected hosts, who are prone to develop oral hairy leukoplakia, has no t been studied. Methods: Tongue scrapings and CD45+-enriched periphera l blood cells of 20 HIV-1-infected patients and 40 healthy controls we re examined. EBV-specific DNA was amplified from segments in the first intron of the BZLF-1 gene, in exon C of the LMP-1 gene, and the type A/B-specifying domain of the EBNA-3C gene. Size polymorphisms of these amplicons were assessed by agarose gel electrophoresis, and DNA seque nce differences among BZLF-1 gene amplicons by single-strand conformat ion polymorphism analysis. Results: The predominant EBV genotype in pe ripheral blood as well as tongue carried two copies of the BZLF-1 repe at. In controls, although the BZLF-1 genotype with two copies was excl usively detected in the blood, the genotype with three copies predomin ated in the tongue. The findings could not be correlated with EBV geno typed according size polymorphisms in the EBNA-3C or LMP-1 genes. DNA sequences of a proportion or all of the clones derived from the BZLF-1 amplicons in the tongues of HIV-1-infected patients were identical to those in the blood. Conclusions: These findings are consistent with E BV haematogenous superinfection of the tongue of HIV-positive individu als. Such superinfection may precede or lead to the development of ora l hairy leukoplakia. (C) 1998 Lippincott Williams & Wilkins