title: Screening for potential prophylactics targeting sporozoite motility through the skin creator: Douglas, Ross G. creator: Reinig, Miriam creator: Neale, Matthew creator: Frischknecht, Friedrich subject: ddc-610 subject: 610 Medical sciences Medicine description: Background: Anti-malarial compounds have not yet been identified that target the first obligatory step of infection in humans: the migration of Plasmodium sporozoites in the host dermis. This movement is essential to find and invade a blood vessel in order to be passively transported to the liver. Here, an imaging screening pipeline was established to screen for compounds capable of inhibiting extracellular sporozoites. Methods: Sporozoites expressing the green fluorescent protein were isolated from infected Anopheles mosquitoes, incubated with compounds from two libraries (MMV Malaria Box and a FDA-approved library) and imaged. Effects on in vitro motility or morphology were scored. In vivo efficacy of a candidate drug was investigated by treating mice ears with a gel prior to infectious mosquito bites. Motility was analysed by in vivo imaging and the progress of infection was monitored by daily blood smears. Results: Several compounds had a pronounced effect on in vitro sporozoite gliding or morphology. Notably, monensin sodium potently affected sporozoite movement while gramicidin S resulted in rounding up of sporozoites. However, pre-treatment of mice with a topical gel containing gramicidin did not reduce sporozoite motility and infection. Conclusions: This approach shows that it is possible to screen libraries for inhibitors of sporozoite motility and highlighted the paucity of compounds in currently available libraries that inhibit this initial step of a malaria infection. Screening of diverse libraries is suggested to identify more compounds that could serve as leads in developing ‘skin-based’ malaria prophylactics. Further, strategies need to be developed that will allow compounds to effectively penetrate the dermis and thereby prevent exit of sporozoites from the skin. publisher: BioMed Central date: 2018 type: Article type: info:eu-repo/semantics/article type: NonPeerReviewed format: application/pdf identifier: https://archiv.ub.uni-heidelberg.de/volltextserver/25454/1/12936_2018_Article_2469.pdf identifier: DOI: identifier: urn:nbn:de:bsz:16-heidok-254545 identifier: Douglas, Ross G. ; Reinig, Miriam ; Neale, Matthew ; Frischknecht, Friedrich (2018) Screening for potential prophylactics targeting sporozoite motility through the skin. Malaria journal, 17 (319). pp. 1-10. ISSN 1475-2875 relation: https://archiv.ub.uni-heidelberg.de/volltextserver/25454/ rights: info:eu-repo/semantics/openAccess rights: Please see front page of the work (Sorry, Dublin Core plugin does not recognise license id) language: eng