High levels of antibodies to Plasmodium falciparum liver stage antigen-1 in naturally infected individuals in Myanmar

Abstract

Plasmodium falciparum liver stage antigen-1 (PfLSA-1) is one of the few antigens expressed exclusively in liver stage parasites. In this study, we evaluated the antibody responses against recombinant PfLSA-1 in naturally infected individuals in Myanmar. High levels of antibody responses (70.7%) were detected in 82 serum samples from 116 infected individuals, and IgG responses to PfLSA-1 principally composed of responses of IgG1 and IgG3 subclasses. These results show that PfLSA-1 elicits effective antibody responses in individuals infected with P. falciparum, and thus it could be not only an attractive candidate protein for vaccine development, but also a useful antigen for serodiagnosis of the infection.

Fig. 1

Expression and purification of rPfLSA-1. SDS-PAGE analysis of the expressed rPfLSA-1 protein. Lane M, molecular weight marker proteins; Lane 1, non-induced E. coli cell lysate; Lane 2, induced E. coli cell lysate; Lane 3, purified protein from induced E. coli cell lysate using Ni-NTA column.

Fig. 2

Western blot analysis of the purified rPfLSA-1 against the sera from patients naturally infected with P. falciparum in Myanmar and from normal people. Only representative reactions are shown.

Fig. 3

IgG subclass responses against rPfLSA-1 in the sera from patients naturally infected with P. falciparum in Myanmar.