{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T18:10:07Z","timestamp":1778350207698,"version":"3.51.4"},"reference-count":40,"publisher":"Public Library of Science (PLoS)","issue":"7","license":[{"start":{"date-parts":[[2024,7,5]],"date-time":"2024-07-05T00:00:00Z","timestamp":1720137600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100010679","name":"Pasteur Institute of Iran","doi-asserted-by":"publisher","award":["1215"],"award-info":[{"award-number":["1215"]}],"id":[{"id":"10.13039\/501100010679","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003968","name":"Iran National Science Foundation","doi-asserted-by":"publisher","award":["99014037"],"award-info":[{"award-number":["99014037"]}],"id":[{"id":"10.13039\/501100003968","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:sec id=\"sec001\">\n<jats:title>Backgrounds<\/jats:title>\n<jats:p>Malaria, a preventive and treatable disease, is still responsible for annual deaths reported in most tropical regions, principally in sub-Saharan Africa. Subunit recombinant transmission-blocking vaccines (TBVs) have been proposed as promising vaccines to succeed in malaria elimination and eradication. Here, a provisional study was designed to assess the immunogenicity and functional activity of alanyl aminopeptidase N (APN1) of <jats:italic>Anopheles stephensi<\/jats:italic>, as a TBV candidate, administered with MPL, CpG, and QS21 adjuvants in the murine model.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Methodology\/Principal findings<\/jats:title>\n<jats:p>The mouse groups were immunized with recombinant APN1 (rAPN1) alone or formulated with CpG, MPL, QS-21, or a combination of adjuvants (CMQ), and the elicited immune responses were evaluated after the third immunization. The standard membrane feeding assay (SMFA) measured the functional activity of antibodies against bacterial-expressed APN1 protein in adjuvanted vaccine groups on transmission of <jats:italic>P<\/jats:italic>. <jats:italic>falciparum<\/jats:italic> (NF54) to <jats:italic>An<\/jats:italic>. <jats:italic>stephensi<\/jats:italic> mosquitoes. Evaluation of mice vaccinated with rAPN1 formulated with distinct adjuvants manifested a significant increase in the high-avidity level of anti-APN1 IgG and IgG subclasses; however, rAPN1 induced the highest level of high-avidity anti-APN1 IgG1, IgG2a, and IgG2b antibodies in the immunized vaccine group 5 (APN1\/CMQ). In addition, vaccine group 5 (receiving APN1\/CMQ), had still the highest level of anti-APN1 IgG antibodies relative to other immunized groups after six months, on day 180. The SMFA data indicates a trend towards higher transmission-reducing activity in groups 2 and 5, which received the antigen formulated with CpG or a combination of three adjuvants.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Conclusions\/Significance<\/jats:title>\n<jats:p>The results have shown the capability of admixture to stimulate high-affinity and long-lasting antibodies against the target antigen to hinder <jats:italic>Plasmodium<\/jats:italic> parasite development in the mid-gut of <jats:italic>An<\/jats:italic>. <jats:italic>stephensi<\/jats:italic>. The attained results authenticated APN1\/CMQ and APN1\/CpG as a potent APN1-based TBV formulation which will be helpful in designing a vaccine in the future.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0306664","type":"journal-article","created":{"date-parts":[[2024,7,5]],"date-time":"2024-07-05T17:40:22Z","timestamp":1720201222000},"page":"e0306664","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":2,"title":["Malaria transmission blocking activity of Anopheles stephensi alanyl aminopeptidase N antigen formulated with MPL, CpG, and QS21 adjuvants"],"prefix":"10.1371","volume":"19","author":[{"given":"Zeinab","family":"Pourhashem","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Leila","family":"Nourani","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sakineh","family":"Pirahmadi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hemn","family":"Yousefi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jafar","family":"J. 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