Recombinant proteins of Plasmodium malariae merozoite surface protein 1 (PmMSP1): Testing immunogenicity in the BALB/c model and potential use as diagnostic tool

• DOI: 10.1371/journal.pone.0219629
• Publication Date: 2019-07-25T17:32:40Z
• Authors: Yelina B. Elizardez; Wesley L. Fotoran; Andrés J. Galiste...; Izilda Curado; Norival Kesper Ju...; Eliana F. Monteiro; Irineu Romero Neto; Gerhard Wunderlich; Karin Kirchgatter
• Keywords: Merozoite surface protein; Plasmodium malariae

Plasmodium malariae is the third most prevalent human malaria-causing species and has a patchy, but ample distribution in world. Humans can host parasite for years without presenting significant symptoms, turning its diagnosis control into difficult task. Here, we investigated immunogenicity of recombinant proteins P. MSP1.Five regions PmMSP1 were expressed Escherichia coli as GST-fusion immunized BALB/c mice. The specificity, subtyping, affinity raised antibodies evaluated by enzyme-linked immunosorbent assays. Cellular immune responses analyzed lymphoproliferation assays cytokine levels produced splenocytes detected cytometry.We found that N-terminal, central regions, PmMSP119 are strongly immunogenic After three doses, induced remained high 70 days. While after immunization with N-terminal showed similar affinities to target antigens, IgG against higher. All antibody subclass patterns (predominantly IgG1, IgG2a, IgG2b), characterizing mixed Th1/Th2 response. Further, autologous stimulation from mice led secretion IL2 IL4, independently antigen used. Importantly, malariae-exposed individuals reacted specificity. On other hand, sera vivax or falciparum-infected did not react at all proteins.Recombinant very useful diagnostic markers epidemiological studies differential malaria caused this species. Immunization resulted humoral response, which may turn them potential component candidates vaccine malariae.