More Like this

1. Adsorptive exchange of coccolith biominerals facilitates viral infection

   https://doi.org/10.1126/sciadv.adc8728  

   Johns, Christopher T.; Bondoc-Naumovitz, Karen Grace; Matthews, Alexandra; Matson, Paul G.; Iglesias-Rodriguez, M. Debora; Taylor, Alison R.; Fuchs, Heidi L.; Bidle, Kay D. (January 2023, Science Advances)

   n/a (Ed.)

   Marine coccolithophores are globally distributed, unicellular phytoplankton that produce nanopatterned, calcite biominerals (coccoliths). These biominerals are synthesized internally, deposited into an extracellular coccosphere, and routinely released into the external medium, where they profoundly affect the global carbon cycle. The cellular costs and benefits of calcification remain unresolved. Here, we show observational and experimental evidence, supported by biophysical modeling, that free coccoliths are highly adsorptive biominerals that readily interact with cells to form chimeric coccospheres and with viruses to form “viroliths,” which facilitate infection. Adsorption to cells is mediated by organic matter associated with the coccolith base plate and varies with biomineral morphology. Biomineral hitchhiking increases host-virus encounters by nearly an order of magnitude and can be the dominant mode of infection under stormy conditions, fundamentally altering how we view biomineral-cell-virus interactions in the environment. 

   more » « less
2. Early HIV Infection Predictions: Role of Viral Replication Errors

   https://doi.org/10.1137/17M1134019  

   Conway, Jessica M.; Perelson, Alan S. (January 2018, SIAM Journal on Applied Mathematics)
3. Spatial propagation in a within‐host viral infection model

   https://doi.org/10.1111/sapm.12490  

   Wang, Xinjian; Lin, Guo; Ruan, Shigui (February 2022, Studies in Applied Mathematics)

   Abstract Recent experimental evidence suggests that spatial heterogeneity plays an important role in within‐host infections caused by different viruses including hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV). To examine the spatial effects of viral infections, in this paper we study the asymptotic spreading in a within‐host viral infection model, which describes the spatial expansion speeds of viruses and infected cells within an infected host. We first establish the boundedness of solutions to the Cauchy problem via local ‐estimates and dual arguments. Then the spreading speed is estimated when the basic reproduction number of the corresponding kinetic system is larger than one. More precisely, the upper bounds of the spreading speed are given by constructing suitable upper solutions while the lower bounds of the spreading speed are obtained by introducing an auxiliary equation with nonlocal delay. When the basic reproduction number of the corresponding kinetic system is less than or equal to one, the virus dies out uniformly. Finally, we present some numerical simulations to illustrate our theoretical findings and discuss the biological relevance of these results. 

   more » « less
4. Female reproduction and viral infection in a long‐lived mammal

   https://doi.org/10.1111/1365-2656.13799  

   Negrey, Jacob D.; Emery Thompson, Melissa; Dunn, Christopher D.; Otali, Emily; Wrangham, Richard W.; Mitani, John C.; Machanda, Zarin P.; Muller, Martin N.; Langergraber, Kevin E.; Goldberg, Tony L. (October 2022, Journal of Animal Ecology)

   Abstract For energetically limited organisms, life‐history theory predicts trade‐offs between reproductive effort and somatic maintenance. This is especially true of female mammals, for whom reproduction presents multifarious energetic and physiological demands.Here, we examine longitudinal changes in the gut virome (viral community) with respect to reproductive status in wild mature female chimpanzeesPan troglodytes schweinfurthiifrom two communities, Kanyawara and Ngogo, in Kibale National Park, Uganda.We used metagenomic methods to characterize viromes of individual chimpanzees while they were cycling, pregnant and lactating.Females from Kanyawara, whose territory abuts the park's boundary, had higher viral richness and loads (relative quantity of viral sequences) than females from Ngogo, whose territory is more energetically rich and located farther from large human settlements. Viral richness (total number of distinct viruses per sample) was higher when females were lactating than when cycling or pregnant. In pregnant females, viral richness increased with estimated day of gestation. Richness did not vary with age, in contrast to prior research showing increased viral abundance in older males from these same communities.Our results provide evidence of short‐term physiological trade‐offs between reproduction and infection, which are often hypothesized to constrain health in long‐lived species. 

   more » « less
5. Spatially distributed infection increases viral load in a computational model of SARS-CoV-2 lung infection

   https://doi.org/10.1371/journal.pcbi.1009735  

   Moses, Melanie E.; Hofmeyr, Steven; Cannon, Judy L.; Andrews, Akil; Gridley, Rebekah; Hinga, Monica; Leyba, Kirtus; Pribisova, Abigail; Surjadidjaja, Vanessa; Tasnim, Humayra; et al (December 2021, PLOS Computational Biology)

   Smith, Amber M (Ed.)

   A key question in SARS-CoV-2 infection is why viral loads and patient outcomes vary dramatically across individuals. Because spatial-temporal dynamics of viral spread and immune response are challenging to study in vivo, we developed Spatial Immune Model of Coronavirus (SIMCoV), a scalable computational model that simulates hundreds of millions of lung cells, including respiratory epithelial cells and T cells. SIMCoV replicates viral growth dynamics observed in patients and shows how spatially dispersed infections can lead to increased viral loads. The model also shows how the timing and strength of the T cell response can affect viral persistence, oscillations, and control. By incorporating spatial interactions, SIMCoV provides a parsimonious explanation for the dramatically different viral load trajectories among patients by varying only the number of initial sites of infection and the magnitude and timing of the T cell immune response. When the branching airway structure of the lung is explicitly represented, we find that virus spreads faster than in a 2D layer of epithelial cells, but much more slowly than in an undifferentiated 3D grid or in a well-mixed differential equation model. These results illustrate how realistic, spatially explicit computational models can improve understanding of within-host dynamics of SARS-CoV-2 infection. 

   more » « less