1. First evaluation of antibody responses to Culex quinquefasciatus salivary antigens as a serological biomarker of human exposure to Culex bites: A pilot study in Côte d’Ivoire
- Author
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Bi Zamble H Zamble, Serge S Yao, Akré M Adja, Mahfoud Bakli, Dounin D Zoh, Françoise Mathieu-Daudé, Serge B Assi, Franck Remoue, Lionel Almeras, Anne Poinsignon, Institut Pierre Richet (IPR), Institut Pasteur de Côte d'Ivoire, Réseau International des Instituts Pasteur (RIIP), Maladies infectieuses et vecteurs : écologie, génétique, évolution et contrôle (MIVEGEC), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Vecteurs - Infections tropicales et méditerranéennes (VITROME), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut de Recherche Biomédicale des Armées [Brétigny-sur-Orge] (IRBA), Institut de Recherche Biomédicale des Armées [Antenne Marseille] (IRBA), and Institut Hospitalier Universitaire Méditerranée Infection (IHU Marseille)
- Subjects
Male ,RC955-962 ,Antibody Response ,Pilot Projects ,Disease Vectors ,Mosquitoes ,Biochemistry ,Salivary Glands ,Families ,Medical Conditions ,[SDV.MHEP.MI]Life Sciences [q-bio]/Human health and pathology/Infectious diseases ,Arctic medicine. Tropical medicine ,Medicine and Health Sciences ,Child ,Immune Response ,Children ,[SDV.MHEP.ME]Life Sciences [q-bio]/Human health and pathology/Emerging diseases ,Eukaryota ,Recombinant Proteins ,Insects ,Culex ,Infectious Diseases ,Child, Preschool ,[SDV.MP.VIR]Life Sciences [q-bio]/Microbiology and Parasitology/Virology ,Female ,Public aspects of medicine ,RA1-1270 ,Anatomy ,Research Article ,Adolescent ,Arthropoda ,Immunology ,Culex Quinquefasciatus ,Exocrine Glands ,[SDV.MHEP.CSC]Life Sciences [q-bio]/Human health and pathology/Cardiology and cardiovascular system ,parasitic diseases ,Animals ,Humans ,[SDV.MP.PAR]Life Sciences [q-bio]/Microbiology and Parasitology/Parasitology ,Salivary Proteins and Peptides ,fungi ,Organisms ,Infant ,Insect Bites and Stings ,Biology and Life Sciences ,Proteins ,Invertebrates ,[SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology ,Insect Vectors ,Species Interactions ,Cote d'Ivoire ,Age Groups ,Immunoglobulin G ,People and Places ,Population Groupings ,Zoology ,Entomology ,Digestive System ,Biomarkers - Abstract
Background Culex mosquitoes are vectors for a variety of pathogens of public health concern. New indicators of exposure to Culex bites are needed to evaluate the risk of transmission of associated pathogens and to assess the efficacy of vector control strategies. An alternative to entomological indices is the serological measure of antibodies specific to mosquito salivary antigens. This study investigated whether the human IgG response to both the salivary gland extract and the 30 kDa salivary protein of Culex quinquefasciatus may represent a proxy of human exposure to Culex bites. Methodology/Principal findings A multidisciplinary survey was conducted with children aged 1 to 14 years living in neighborhoods with varying exposure to Culex quinquefasciatus in the city of Bouaké, Côte d’Ivoire. Children living in sites with high exposure to Cx quinquefasciatus had a significantly higher IgG response to both salivary antigens compared with children living in the control site where only very few Culex were recorded. Moreover, children from any Culex-high exposed sites had significantly higher IgG responses only to the salivary gland extract compared with children from the control village, whereas no difference was noted in the anti-30 kDa IgG response. No significant differences were noted in the specific IgG responses between age and gender. Sites and the use of a bed net were associated with the level of IgG response to the salivary gland extract and to the 30 kDa antigen, respectively. Conclusions/Significance These findings suggest that the IgG response to Culex salivary gland extracts is suitable as proxy of exposure; however, the specificity to the Culex genus needs further investigation. The lower antigenicity of the 30 kDa recombinant protein represents a limitation to its use. The high specificity of this protein to the Culex genus makes it an attractive candidate and other specific antibody responses might be more relevant as a biomarker of exposure. These epidemiological observations may form a starting point for additional work on developing serological biomarkers of Culex exposure., Author summary The evaluation of exposure to mosquitoes is a key parameter in assessing the risk of transmission of associated pathogens, including zoonoses. Entomological methods represent the gold standard but have several limitations, and efforts are being made to develop new indicators to accurately assess human–Culex contact. This study showed the IgG response to Culex quinquefasciatus salivary gland extract is suitable proxy of exposure to Culex bites. The lower antigenicity of the 30 kDa recombinant protein represents a limitation to its use. The high specificity of this protein to the Culex genus makes it an attractive candidate and other isotypic antibody responses specific to this salivary antigen might be more relevant as a biomarker of exposure.
- Published
- 2021