Studies on Antigenic Molecules of Plasmodium Falcipalum Using Polyclonal Antibody from Infected Human Subjects

点击翻译按钮获取中文摘要

In 1989, sere from imported malaria cases and from individuals living in various endemic areas were collected. The reactivity of the SDS-fractionated Plasmodium falciparum antigen molecule was tested using the human sera taken from subjects with varying endemic background. Aparitcular parasite molecule was found to be specifically reactive with the sera from acute phase of the infection by Western blot technique. Thus it was hoped that the molecule can be useful to define recent past infection by serological method both at the community level and also in the diagnosis of individual cases. In 1990, the RNA from cultured P. falciparum were extracted, and the lambda gt11 cDNA expression library was prepared using EcoRI adapter. Following immunoscreening using a human serum which is highly reactive with the parasite molecule, a single clone of the recombinant lambda gtll was largery amplifie by growing transfected E. coil Y1090. The insert DNA was cut out by BamHI and ligated to BamHI digested pUC118. The recombinant DNA was injected into E. coli JM109. The transformant cells were again grown to obtain BamHI digested DNA fragment was of the parasite. The resulted DNA fragment nick translated to prepare 32P labeled parasite DNA prode which was applied to Southern hybridazation of BamHI fragmented genomic DNA of the parasite. Thus, a part of the sequence of parasite DNA encoding the antigen molecule was read by means of dideoxyl sequencing analysis on gel. The parasite DNA was not conincidental with already registered parasite gene, however, a similarity was noted with VSG gene of Trypanosoma cruzi.