Seroepidemiological study of <i style="">Plasmodium falciparum</i> antigens for detection of malaria

Abstract

Attempt has been made to develop a simple and cost-effective diagnostic method for the detection of malaria in field conditions. A new type of <i style="">Plasmodium falciparum</i> antigen (PSJ-M strain) from <i style="">in vitro</i> culture supernatant has been isolated. Purification and chemical analysis of the antigen showed that it is a glycophospholipid (GPL1), which contains mannose, xylose, glucose and galactose (3:3:1.5:1.5) in sugar moiety but its structure is devoid of inositol sugar and amino acids. Sensitivity and specificity properties of GPL1, when compared with existing <i style="">P. falciparum</i> antigens by Laser light scattering immunoassay (LIA) and Enzyme linked immunosorbent assay (ELISA), showed that the antigen has a very high sensitivity for detection of <i style="">P. falciparum</i> malaria antibodies; also specificity percentage was found to be 98%. The serological properties of GPL1 antigen have also been evaluated in endemic and non-endemic areas of different regions of the country. A simple, economical and handy malaria detection immunosensor (MDI) has been designed and developed for field areas. Laboratory and field trials for detection of <i style="">P. falciparum </i>malaria by MDI showed highly encouraging and good results. Data obtained by MDI from field areas, when compared in laboratory by LIA and ELISA techniques, showed that MDI method had better diagnostic ability and efficacy for detection of <i style="">P. falciparum</i> malaria (94-98%). Results of the study also suggest that GPL1 antigen and MDI can be used for detection and prevention of <i style="">P. falciparum</i> malaria.