Longitudinal analysis of Plasmodium sporozoite motility in the dermis reveals component of blood vessel recognition
- Johns Hopkins Bloomberg School of Public Health, United States
- University of Pennsylvania, United States
- Leiden University Medical Center, Netherlands
Abstract
Malaria infection starts with injection of Plasmodium sporozoites by an Anopheles mosquito into the skin of the mammalian host. How sporozoites locate and enter a blood vessel is a critical, but poorly understood process. Here, we examine sporozoite motility and their interaction with dermal blood vessels, using intravital microscopy in mice. Our data suggest that sporozoites exhibit two types of motility: In regions far from blood vessels, they exhibit ′avascular motility′, defined by high speed and less confinement, while in the vicinity of blood vessels their motility is more constrained. We find that curvature of sporozoite tracks engaging with vasculature optimizes contact with dermal capillaries. Imaging of sporozoites with mutations in key adhesive proteins highlight the importance of the sporozoite's gliding speed and its ability to modulate adhesive properties for successful exit from the inoculation site.
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Ethics
Animal experimentation: All animal work was conducted in accordance with the recommendations by the Johns Hopkins University Animal Care and Use Committee (IACUC), under the IACUC-approved protocol #M011H467.
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© 2015, Hopp et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Longitudinal analysis of Plasmodium sporozoite motility in the dermis reveals component of blood vessel recognition
eLife 4:e07789.
https://doi.org/10.7554/eLife.07789
Further reading
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- Epidemiology and Global Health
- Microbiology and Infectious Disease
eLife has published papers on many tropical diseases, including malaria, Ebola, leishmaniases, Dengue and African sleeping sickness.
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- Microbiology and Infectious Disease
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