Expanded Histopathology and Tropism of Ebola Virus in the Rhesus Macaque Model: Potential for Sexual Transmission, Altered Adrenomedullary Hormone Production and Early Viral Replication in liver

Am J Pathol. 2021 Oct 6;S0002-9440(21)00434-X. doi: 10.1016/j.ajpath.2021.09.009. Online ahead of print.

Abstract

The pathogenesis of Ebola virus disease (EVD) is still incomplete, although the non-human primate model has been studied for more than 4 decades. To further investigate EVD pathogenesis, a natural history study has been conducted using 27 Chinese-origin rhesus macaques. Of them, 24 macaques were exposed intramuscularly to Kikwit Ebola virus (EBOV) and euthanized at pre-determined timepoints or when end stage clinical disease criteria were met, while 3 other sham-exposed macaques were euthanized at the study day 0. This study demonstrates for the first time that Ebola virus causes uterine cervicitis, vaginitis, posthitis, and medullary adrenalitis. Not only is Ebola virus detected in the interstitial stromal cells of the genital tract, but it is also present in the epididymal and seminal vesicular tubular epithelial cells, ectocervical and vaginal squamous epithelial cells, and seminal fluid. Furthermore, as early as day 3 after exposure, EBOV replicative intermediate RNA was detected in Kupffer cells and hepatocytes. These findings in the nonhuman model provide additional insight into potential sexual transmission, possible disruption of sympathetic hormone production, and early virus replication sites in human EVD patients.

Keywords: Ebola virus; GP; VP40; and EBOV replication; cervicitis; chromaffin cells; medullary adrenalitis; posthitis; vaginitis.