Liver stage antigen 3 isolated from a cDNA library of Plasmodium falciparum erythrocytic stages.

An expression library of P. falciparum erythrocyte stages (clon Dd2) was constructed and immunoscreened with a sera pool from malaria patients. Isolated clones were analysed, and the liver stage antigen 3 (LSA-3) antigen was identified. The partial nucleotide sequence of LSA-3 has 1,623 bp. The open reading frame coded for the putative protein with 541 amino acid residues. We have demonstrated by reverse transcriptase polymerase chain reaction the transcription of the LSA-3 gene in ring form, trophozoite, and schizont, stages of asexual erythrocyte cycle.