{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:33:50Z","timestamp":1760142830639,"version":"build-2065373602"},"reference-count":33,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2024,1,5]],"date-time":"2024-01-05T00:00:00Z","timestamp":1704412800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Council for Scientific and Technological Development","award":["317528\/2021-1\u2014PQ2","200.980\/2021\u2014CNE","205.014\/2022\u2014TCT 5","001"],"award-info":[{"award-number":["317528\/2021-1\u2014PQ2","200.980\/2021\u2014CNE","205.014\/2022\u2014TCT 5","001"]}]},{"name":"Carlos Chagas Filho Foundation for Research Support in Rio de Janeiro","award":["317528\/2021-1\u2014PQ2","200.980\/2021\u2014CNE","205.014\/2022\u2014TCT 5","001"],"award-info":[{"award-number":["317528\/2021-1\u2014PQ2","200.980\/2021\u2014CNE","205.014\/2022\u2014TCT 5","001"]}]},{"name":"Coordination for the Improvement of Higher Education Personnel","award":["317528\/2021-1\u2014PQ2","200.980\/2021\u2014CNE","205.014\/2022\u2014TCT 5","001"],"award-info":[{"award-number":["317528\/2021-1\u2014PQ2","200.980\/2021\u2014CNE","205.014\/2022\u2014TCT 5","001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Malaria is caused by apicomplexan parasites of the Plasmodium genus. Plasmodium chabaudi is an excellent animal model for the study of human malaria caused by P. falciparum. Merozoites invade erythrocytes but are also found in other host cells including macrophages from the spleen and liver. Methodologies for obtaining merozoites usually involve treatment with protease inhibitors. However, merozoites obtained in this way may have their enzymatic profile altered and, therefore, are not ideal for cell-interaction assays. We report the obtainment of P. chabaudi merozoites naturally egressed from a synchronous erythrocyte population infected with schizonts forms. Merozoites had their infectivity and ultrastructure analyzed. Interaction assays were performed with mice erythrocytes and classically activated mice peritoneal macrophages, a very well-established classic model. Obtained merozoites were able to kill mice and efficiently infect erythrocytes. Interestingly, a lower merozoite:erythrocyte ratio resulted in a higher percentage of infected erythrocytes. We describe a simpler method for obtaining viable and infective merozoites. Classically activated macrophages killed merozoites, suggesting that these host cells may not serve as reservoirs for these parasites. These findings have implications for our understanding of P. chabaudi merozoite biology and may improve the comprehension of their host\u2013parasite relationship.<\/jats:p>","DOI":"10.3390\/microorganisms12010105","type":"journal-article","created":{"date-parts":[[2024,1,5]],"date-time":"2024-01-05T03:43:00Z","timestamp":1704426180000},"page":"105","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Plasmodium chabaudi Merozoites Obtained through a Simpler Method Do Not Survive in Classically Activated Macrophages"],"prefix":"10.3390","volume":"12","author":[{"given":"Pedro Souto","family":"Rodrigues","sequence":"first","affiliation":[{"name":"Laborat\u00f3rio de Biologia Celular e Tecidual, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes 28013-602, RJ, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Milena de Farias","family":"Azeredo","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Biologia Celular e Tecidual, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes 28013-602, RJ, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nat\u00e1lia de Souza","family":"Almeida","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Biologia Celular e Tecidual, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes 28013-602, RJ, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gisela Garcia Cabral Galaxe","family":"de Almeida","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Biologia Celular e Tecidual, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes 28013-602, RJ, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jo\u00e3o Luiz Mendes","family":"Wanderley","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Imunoparasitologia, Universidade Federal do Rio de Janeiro, Maca\u00e9 27930-560, RJ, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sergio Henrique","family":"Seabra","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Biologia Celular e Tecidual, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes 28013-602, RJ, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0108-9268","authenticated-orcid":false,"given":"Renato Augusto","family":"DaMatta","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Biologia Celular e Tecidual, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes 28013-602, RJ, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,1,5]]},"reference":[{"key":"ref_1","unstructured":"WHO (2022). 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