Biology subjects

Pearson, V. R.

Publications and source records attributed to Pearson, V. R..

4 recordsLinked to original sources

bioRxiv2026

PERSISTENT LOW-LEVEL INFECTIONS OF ELEPHANT ENDOTHELIOTROPIC HERPESVIRUS AND ELEPHANT GAMMAHERPESVIRUSDETECTED IN SKIN NODULES AND SALIVA FROM WILD AND ZOO AFRICAN ELEPHANTS

The goal of this study was to determine which species of Elephant Endotheliotropic Herpesviruses (EEHV) and Elephant Gammaherpesviruses (EGHV) are endemic in wild African elephants, Loxodonta. We collected skin nodule biopsies, saliva and tissues from 43 wild L. africana (African bush elephant) in Botswana, Kenya, South Africa and Zimbabwe; and saliva from 25 wild L. cyclotis (African forest elephant) in Gabon. We also collected saliva over seven years from 7 wild-born L. africana at Six Flags Safari Park, USA, and saliva, blood and tissues from an additional 200 L. africana and Elephas maximus in USA zoos. Conventional polymerase chain reaction and Sanger sequencing of purified DNA from these samples yielded thousands of unambiguous positive genetic matches to known EEHV2, EEHV3A, EEHV3B, EEHV6, EEHV7A, EGHV2, EGHV3B, EGHV4B, EGHV5B, and discovered new species EEHV3C-H, EEHV7B and EGHV1B in African elephants, and EGHV5A in an Asian elephant. Our extensive library of EEHV and EGHV sequences from wild and zoo elephants provide a significant resource to the elephant virologists and conservationists.

molecular biology↗

bioRxiv2025

Neutrophil extracellular traps offer a new therapeutic target for elephant endotheliotropic herpes hemorrhagic disease (EEHV-HD)

Elephant survival is threatened by a devastating hemorrhagic disease called elephant endotheliotropic herpes virus-hemorrhagic disease (EEHV-HD). Once clinical signs are observed in elephants, the disease progresses rapidly and frequently results in death. EEHV-HD negatively impacts elephant conservation because very young, reproductively immature elephants are most at risk for death. Ongoing efforts to understand disease pathogenesis and progression may identify treatment targets and improve clinical outcomes. In some lethal EEHV-HD cases, microthrombosis has been observed in organ tissues similar to other hemorrhagic diseases in humans and animals where sticky webs of protein-coated DNA strands called neutrophil extracellular traps (NETs) exacerbate thrombosis and hemorrhage associated with disseminated intravascular coagulation (DIC). In this study, we sought to identify if NET formation occurs in elephants and could contribute to poor outcomes in EEHV-HD. Our study demonstrated NET release for the first time from elephant heterophils (neutrophils) that occurred in response to various stimuli, including plasma from EEHV-HD affected elephants. EEHV-HD affected tissues contained extensive NETs suggesting that dysregulated NET formation contributes to pathogenesis of this disease. Importantly, elephant neutrophils were blocked from releasing NETs in response to EEHV-HD plasma using known NET inhibitors. The ability to stop NETs in EEHV-HD offers a new therapeutic approach that could be combined with current therapies to improve survival for affected elephants and to positively impact conservation efforts.

immunology↗

bioRxiv2024

Quiescent Infections of Elephant Endotheliotropic Herpesviruses and Elephant Gammaherpesviruses in African Elephants in Botswana, Gabon, Kenya, South Africa and USA

This novel study detected persistent low-level infection of Elephant Endotheliotropic Herpesviruses (EEHV), that can cause highly pathogenic Elephant Hemorrhagic Disease (EHD) in Loxodonta and Elephas, and co-infection of presumed less pathogenic Elephant Gammaherpesviruses (EGHV), in skin nodule biopsies, saliva and tissues collected from 43 wild L. africana (savannah elephant) in Botswana, Kenya, South Africa and Zimbabwe; in saliva from 25 wild L. cyclotis (forest elephant) in Gabon and 7 wild-born L.africana at Six Flags Safari Park, USA, over an extended period of seven years; and in saliva, blood and tissues from an additional 200 L. africana and 100 Elephas maximus in USA zoos. DNA from these samples was extracted in our USA laboratories and amplified by conventional polymerase chain reaction using three-round nested primer sets designed specifically to screen for known EEHV and EGHV genes loci and to discover new species and subtypes. Sanger sequencing of purified DNA from nearly all samples yielded unambiguous positive genetic matches to previously known Loxodonta-associated EEHV2, EEHV3A, EEHV3B, EEHV6, EEHV7A, and EGHV1B, EGHV2, EGHV3B, EGHV4B, EGHV5B and discovered novel types EEHV3C-H and EEHV7B and the prototype EGHV1B. Many of the primer sets used could also have detected known Elephas-associated EEHV1A, EEHV1B, EEHV4, and EEHV5 if present, but they did not. This extensive EEHV and EGHV sequence library will be a significant contribution to the elephant virology community.

molecular biology↗

bioRxiv2023

Genomic Resources for Asian (Elephas maximus) and African Savannah Elephant (Loxodonta africana) Conservation and Health Research

We provide novel genomic resources to help understand the genomic traits involved in elephant health and to aid conservation efforts. We sequence 11 elephant genomes (5 African savannah, 6 Asian) from North American zoos, including 9 de novo assemblies. We estimate elephant germline mutation rates and reconstruct demographic histories. Finally, we provide an in-solution capture assay to genotype Asian elephants. This assay is suitable for analyzing degraded museum and non-invasive samples, such as feces and hair. The elephant genomic resources we present here should allow for more detailed and uniform studies in the future to aid elephant conservation efforts and disease research.

genomics↗