Acquired antibody responses against merozoite surface protein-1 19 antigen during Plasmodium falciparum and P.vivax infections in South Indian city of Mangaluru

AbstractMerozoite surface protein-1 (MSP-1) of malaria parasites has been extensively studied as a malaria vaccine candidate and the antibody response to this protein is an important indicator of protective immunity to malaria. Mangaluru city and its surrounding areas in southwestern India are endemic to malaria withPlasmodium vivax being the most widespread and prevalent species althoughP. falciparum also frequently infects. However, no information is available on the level of protective immunity in this population. In this regard, a prospective hospital-based study was performed in malarial patients to assess antibody responses against the 19-kDa C-terminal portion ofP. vivax andP. falciparum MSP-1 (MSP-119). Serum samples from 51 healthy endemic controls and 267 infected individuals were collected and anti-MSP-119 antibody levels were analyzed by ELISA. The possible association between the antibody responses and morbidity parameters such as malarial anemia and thrombocytopenia was investigated. Among the 267 infected cases, 144 hadP. vivax and 123 hadP. falciparum infections. Significant levels of anti-MSP-119 antibody were observed both inP. vivax (123/144; 85.4%) andP.falciparum (108/123; 87.9%) infected individuals. In both type of infections, the major antibody isotypes were IgG1 and IgG3. The IgG levels were found to be increased in patients with severe anemia and thrombocytopenia. The antibody levels were also higher in infected individuals who had several previous i...
Source: Journal of Parasitic Diseases - Category: Parasitology Source Type: research