Lytic replication of Epstein-Barr virus in the peripheral blood: analysis
of viral gene expression in B lymphocytes during infectious mononucleosis
and in the normal carrier state
NS Prang, MW Hornef, M Jager, HJ Wagner, H Wolf and FM Schwarzmann
Institut fur Medizinische Mikrobiologie und Hygiene, Universitat
Regensburg, Germany.
Epstein-Barr virus (EBV) has been shown to establish latency in resting B
lymphocytes of the peripheral blood. This creates a virus reservoir in
contrast to lytic virus replication, which is thought to be restricted to
differentiated epithelial cells in vivo. So far, the route of transmission
between B cells and the production of progeny virus in the epithelial
tissue has remained unclear. Reverse transcriptase-polymerase chain
reaction (RT-PCR) and immunohistochemistry analysis of 16 patients with
acute infectious mononucleosis (IM) and 25 healthy seropositive donors was
performed to detect lytic replication gene products in B lymphocytes of the
peripheral blood. Transcriptional activity was found in peripheral blood B
lymphocytes (PBLs) for BZLF1 in 88%, BALF2 in 50%, and BcLF1 in 25% of the
tested IM patients. All positive results were further confirmed in enriched
B-cell populations by antigen determination using immunostaining with the
APAAP technique. Furthermore, we detected transcripts for BZLF1 in 72% and
for BALF2 in 16% of peripheral B lymphocytes of healthy seropositive
donors. In contrast to patients with IM, no signals for BcLF1 were ever
found in healthy seropositive donors. In these individuals, lytic
replication of EBV is probably restricted by immunologic and gene
regulatory mechanisms, whereas in the absence of immunologic control,
reflected here by IM patients, the production of infectious virus becomes
visible in PBLs.
Volume 89,
Issue 5,
pp. 1665-1677,
03/01/1997
Copyright © 1997 by The American Society of Hematology
