{
  "abstract": "Malaria transmission relies on the differentiation of asexual parasites into gametocytes, a process initiated by sexual conversion (SC). Mutations in the host hemoglobin beta (HBB) gene are known to influence parasite growth and disease outcome, yet their impact on SC remains unclear. We investigated the effect of HBB mutant genotypes on Plasmodium falciparum (P. falciparum) SC and humoral immunity in individuals from Nanoro, Burkina Faso. To measure SC rates in natural human malaria infections, we developed a new ex vivo SC assay (evSCA). We found that in human natural P. falciparum infections, SC rates were higher in individuals with HbAS or HbAC than in individuals with wild-type HBB (HbAA). Consistently, using an in vitro SC assay (ivSCA) based on the NF54-gexp02-Tom reporter line we found that cultures grown in HbAS red blood cells (RBCs) had higher SC rates than those grown in HbAA RBCs. Furthermore, IgG and IgM responses against trophozoite- and stage I gametocyte-infected RBC antigens, quantified by flow cytometry, did not differ between plasma from individuals with different HBB genotypes. These results demonstrate that exposure to RBCs with HBB mutations enhances SC, highlighting a host-genetic factor that may influence malaria transmission potential. Author summary: Transmission of Plasmodium falciparum, a malaria causing parasite, depends on the parasite’s ability to produce gametocytes, the stage that infects mosquitoes. In many African regions where malaria is common, hemoglobin (Hb) variants such as hemoglobin S (the sickle-cell trait) and C are highly prevalent reflecting their role in protecting against severe disease. However, it remains unclear whether these variants also influence the parasite’s early shift toward gametocyte development (i.e., sexual conversion [SC]). In this study, we combined ex vivo and in vitro SC assays to measure SC in red blood cells with different hemoglobin genotypes. We found that SC was higher in parasites growing in red blood cells carrying hemoglobin AC and AS genotypes compared to normal AA hemoglobin. These findings provide experimental support for earlier epidemiological observations reporting that individuals with these hemoglobin variants often carry more gametocytes and are more infectious to mosquitoes. We also measured antibody levels in individuals with mutant RBCs and found no differences in immunity that could explain the variation in SC. Our results show that host genetic background can influence gametocyte development and may shape the infectious reservoir in high-burden settings. This knowledge is important for designing effective strategies for malaria elimination.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium",
    "Laboratory of Microbiology, Parasitology and Hygiene (LMPH), Infla-Med Centre of Excellence, University of Antwerp, Antwerp, Belgium",
    "Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de la Santé, Nanoro, Burkina Faso",
    "ISGlobal, Barcelona, Catalonia, Spain",
    "Laboratoire de Biochimie et d’Immunologie Appliquées (LaBIA), Ecole Doctorale Sciences et Technologies, Université Joseph Ki-Zerbo, Ouagadougou, Burkina Faso",
    "Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium",
    "Hematology and Hemostasis Unit, Universitair Ziekenhuis Antwerpen (UZA), Antwerp, Belgium",
    "ICREA, Barcelona, Catalonia, Spain"
  ],
  "article_type": "Research Article",
  "arxiv": null,
  "author_total": 17,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Yasmina Drissi-El Boukili"
    },
    {
      "affs": [
        1
      ],
      "name": "Vera Kühne"
    },
    {
      "affs": [
        2
      ],
      "name": "H. Magloire Natama"
    },
    {
      "affs": [
        3
      ],
      "name": "Pieter Moris"
    },
    {
      "affs": [
        4
      ],
      "name": "Elisabet Tintó-Font"
    },
    {
      "affs": [
        5
      ],
      "name": "Antonia Windkouni Bere"
    },
    {
      "affs": [
        6
      ],
      "name": "Odin Goovaerts"
    },
    {
      "affs": [
        7
      ],
      "name": "Pieter Guetens"
    },
    {
      "name": "Ana Moreno-Murillo"
    },
    {
      "name": "Yarno Valgaerts"
    },
    {
      "name": "T. Edwig Traoré"
    },
    {
      "name": "D. Florence Ouedraogo"
    },
    {
      "name": "Halidou Tinto"
    },
    {
      "name": "Ann Van de Velde"
    },
    {
      "name": "Alfred Cortés"
    },
    {
      "name": "Guy Caljon"
    },
    {
      "name": "Anna Rosanas-Urgell"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/5qt93f91360gd.bib",
  "cited_by": 0,
  "doi": "10.1371/journal.ppat.1014542",
  "fulltext_url": "https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1014542",
  "id": "5qt93f91360gd",
  "issns": [
    "1553-7374"
  ],
  "landing_url": "https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1014542",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2739|Malaria Research and Control"
    ],
    [
      "plos",
      "/Biology and life sciences/Biochemistry/Proteins/Hemoglobin"
    ],
    [
      "plos",
      "/Biology and life sciences/Cell biology/Cellular types/Animal cells/Germ cells/Gametocytes"
    ],
    [
      "plos",
      "/Biology and life sciences/Organisms/Eukaryota/Protozoans/Parasitic protozoans/Malarial parasites"
    ],
    [
      "plos",
      "/Biology and life sciences/Parasitology/Parasite groups/Apicomplexa/Plasmodium"
    ],
    [
      "plos",
      "/Biology and life sciences/Parasitology/Quantitative parasitology/Parasitemia"
    ],
    [
      "plos",
      "/Medicine and health sciences/Medical conditions/Parasitic diseases"
    ],
    [
      "plos",
      "/Medicine and health sciences/Medical conditions/Parasitic diseases/Malaria"
    ],
    [
      "plos",
      "/Medicine and health sciences/Medical conditions/Tropical diseases/Malaria"
    ],
    [
      "plos",
      "/Research and analysis methods/Spectrum analysis techniques/Spectrophotometry/Cytophotometry/Flow cytometry"
    ]
  ],
  "openalex": "W7214746363",
  "pdf_url": "https://journals.plos.org/plospathogens/article/file?id=10.1371/journal.ppat.1014542&type=printable",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-29",
  "publisher": "Public Library of Science",
  "ris": "https://research.draconitic.com/paper/5qt93f91360gd.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:37Z",
      "native_id": "10.1371/journal.ppat.1014542",
      "source": "plos",
      "url": "https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1014542"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "plos:cell biology",
      "subfield": "cell-biology"
    },
    {
      "field": "biology",
      "origin": "plos:parasitology",
      "subfield": "microbiology"
    }
  ],
  "title": "Elevated Plasmodium falciparum sexual conversion in HbAC and HbAS red blood cells in naturally infected malaria patients",
  "title_text": "Elevated Plasmodium falciparum sexual conversion in HbAC and HbAS red blood cells in naturally infected malaria patients",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:17:37Z",
  "url": "https://research.draconitic.com/paper/5qt93f91360gd",
  "venue": "PLOS Pathogens",
  "versions": []
}