Biology subjects

Huff, R.

Publications and source records attributed to Huff, R..

4 recordsLinked to original sources

bioRxiv2026

Cross-Continental Analysis of Vampire Bat Betaherpesvirus Reveals Limited Interference Among Strains and Local Geographic Spread

Desmodus rotundus Betaherpesvirus (DrBHV) is a candidate vector for a transmissible vaccine targeting the circulation of rabies virus within its vampire bat reservoir. Studies assessing the potential for DrBHV as a vector have not considered its geographic range, potential for transboundary spread or how the diversity of wildtype DrBHV in natural bat populations might impede the spread of a modified vaccine strain. Here, by sequencing DrBHVs from vampire bats spanning 15 regions across 7 rabies-affected countries in Latin America and the Caribbean, we characterise the continent-scale distribution of DrBHV diversity and demonstrate widespread and apparently unconstrained co-infection. DrBHV occurred in all regions, forming a monophyletic clade consistent with a single introduction to vampire bats or host-virus co-speciation rather than frequent host switching. Phylogeographic analyses revealed cross-boundary spread that was predicted by geographic proximity. We identified 50 putative DrBHV strains and 79% of DrBHV-infected bats harboured multiple strains. No strains were over- or under-represented in co-infection and co-infections occurred proportionately to local strain prevalence. Whether strains circulated in given populations was predominantly driven by the geographic proximity of other populations containing that strain. The evolutionary relatedness of strains constrained neither rates of co-infection within individuals nor whether strains co-circulated within regions, suggesting vaccine vectors might be locally sourced rather than requiring imported, divergent strains to ameliorate interference. These results support the viability of DrBHV-vectored vaccines for mitigating rabies virus across Latin America and the Caribbean, despite widespread circulation of wildtype viruses.

genomics↗

bioRxiv2024

Genomic insights into Plasmodium vivax and Plasmodium simium host shifts in Latin America

Malaria in Latin America is largely caused by Plasmodium vivax, but its lesser-known sister species, Plasmodium simium, has recently emerged from monkeys to infect humans, thus raising new public health concerns. By analyzing 719 monkey samples and whole genome variations for 19 P. simium and 408 P. vivax isolates, we investigated the evolutionary history and population genetics of the two species. P. vivax, typically restricted to humans, was identified in three Colombian and one Brazilian monkeys, suggesting host niche expansion. Genetic analysis reveals recent genetic exchanges between both species and indicates that P. simium originated from a host jump approximately a century ago, possibly linked to P. vivax migration from Mexico to Brazil. Genome-wide scans revealed signals of positive selection in P. simium genes involved in interactions with primate hosts and mosquito vectors. These findings highlight P. simium evolutionary history and zoonotic malaria risks, and underscore the need to include monkeys in malaria prevention measures while ensuring human-wildlife coexistence.

evolutionary biology↗

bioRxiv2024

Genetic variation in the activity of a TREM2-p53 signaling axis determines oxygen-inducedlung injury

Bronchopulmonary dysplasia (BPD), a chronic lung disease, is the most common major complication of preterm birth. Supplemental oxygen administration, while lifesaving in the neonatal period, remains a key determinant of BPD pathophysiology. Exposure of the immature lung to increased levels of oxygen elicits an inflammatory response resulting in abnormal lung development. However, not every premature infant is equally sensitive to develop BPD. Using genetically diverse mouse strains, we show that the innate immune response activated in the lungs of mice sensitive to hyperoxia that develop BPD-like lung injury differs from mice resilient to disease. Specifically, we identified a selective upregulation of triggering receptor expressed on myeloid cells 2 (TREM2) on lung macrophages and monocytes in the hyperoxia-sensitive C57BL/6J mouse strain. We show that loss of function of TREM2 signaling in myeloid cells resulted in a dramatically improved phenotype after neonatal hyperoxia exposure characterized by a dampened immune response, preserved alveolar structure, and preserved cell proliferative potential supporting normal lung development. At the molecular level, inhibition of TREM2 signaling dampened the magnitude of p53 activation and resulted in cell cycle arrest instead of apoptosis. These findings show that TREM2 is a critical regulator of the pathogenic innate immune response to hyperoxia and highlight its importance as a potential therapeutic target for mitigating injury in the hyperoxia-exposed developing lung.

immunology↗

bioRxiv2023

Aedes aegypti (Dipetera: Culicidae) odorant receptors respond to floral and plant derived volatiles.

Adult mosquitoes require regular sugar meals, usually floral nectar, to survive and flourish in natural habitats. Both males and females locate potential sugar sources using sensory proteins called odorant receptors activated by plant volatiles that facilitate orientation toward flowers or honeydew. The Yellow Fever mosquito, Aedes aegypti (Linnaeus, 1762), possesses a large repertoire of odorant receptors, many of which are likely to support floral odor detection and nectar-seeking. In this study, we have employed a heterologous expression system and the two-electrode voltage clamping technique to identify environmentally relevant chemical compounds that activate specific odorant receptors. Importantly, we have uncovered ligand-receptor pairings for a suite of Aedes aegypti odorant receptors likely to mediate appetitive or aversive behavioral responses, thus shaping a critical aspect of the life history of a medically important mosquito. Moreover, the high degree of conservation of these receptors in other disease-transmitting species suggests common mechanisms of floral odor detection. This knowledge can be used to further investigate mosquito foraging behavior to either enhance existing, or develop novel, control strategies, especially those that incorporate mosquito bait-and-kill or attractive toxic sugar bait technologies.

molecular biology↗