Cytokine and antibody responses to Plasmodium falciparum in naïve individuals during a first malaria episode: effect of age and malaria exposure

• Published in: PloS one Vol. 8; no. 2; p. e55756
• Main Authors: Moncunill, Gemma, Mayor, Alfredo, Jiménez, Alfons, Nhabomba, Augusto, Puyol, Laura, Manaca, Maria N, Barrios, Diana, Cisteró, Pau, Guinovart, Caterina, Aguilar, Ruth, Bardají, Azucena, Pinazo, María-Jesús, Angov, Evelina, Dutta, Sheetij, Chitnis, Chetan E, Muñoz, José, Gascón, Joaquim, Dobaño, Carlota
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 21.02.2013; Public Library of Science (PLoS)
• Subjects: Adult; Adults; Age; Age Factors; Antibody Formation - immunology; Antigens; Biology; Chemokines; Chemokines - blood; Child; Children; Citoquines; Cytokines; Cytokines - blood; Cytokines - immunology; Cytometry; Erythrocytes; Ethics; Exposure; Female; Flow cytometry; Humans; Immune response; Immune system; Immunity; Immunoglobulin G; Immunoglobulin G - blood; Immunoglobulin G - immunology; Immunoglobulins; Infant; Inflammation; Inflammatory response; Interferon; Interleukin 12; Interleukin 2; Interleukin 4; Interleukin 8; Lymphocytes T; Malaria; Malaria, Falciparum - blood; Malaria, Falciparum - immunology; Malaria, Falciparum - parasitology; Male; Malària; Medical research; Medicine; Plasmas (physics); Plasmodium falciparum; Plasmodium falciparum - immunology; Proteins; Recombinant Proteins - metabolism; Seroepidemiologic Studies; Tumor necrosis factor; Vector-borne diseases; γ-Interferon; Spain
• DOI: 10.1371/journal.pone.0055756
• ISSN: 1932-6203

Age- and exposure-dependent immune responses during a malaria episode may be key to understanding the role of these factors in the acquisition of immunity to malaria. Plasma/serum samples collected from naïve Mozambican children (n=48), European adults (naïve travelers, n=22; expatriates with few prior malaria exposures, n=15) and Mozambican adults with long-life malaria exposure (n=99) during and after a malaria episode were analyzed for IgG against merozoite proteins by Luminex and against infected erythrocytes by flow cytometry. Cytokines and chemokines were analyzed in plasmas/sera by suspension array technology. No differences were detected between children and adults with a primary infection, with the exception of higher IgG levels against 3D7 MSP-1(42) (P=0.030) and a P. falciparum isolate (P=0.002), as well as higher IL-12 (P=0.020) in children compared to other groups. Compared to malaria-exposed adults, children, travelers and expatriates had higher concentrations of IFN-γ (P ≤ 0.0090), IL-2 (P ≤ 0.0379) and IL-8 (P ≤ 0.0233). Children also had higher IL-12 (P=0.0001), IL-4 (P=0.003), IL-1β (P=0.024) and TNF (P=0.006) levels compared to malaria-exposed adults. Although IL-12 was elevated in children, overall the data do not support a role of age in immune responses to a first malaria episode. A T(H)1/pro-inflammatory response was the hallmark of non-immune subjects.