Development and evaluation of an enzyme-linked immunosorbent assay for Plasmodium vivax-VK247 sporozoites.
An enzyme-linked immunosorbent assay (ELISA) for the Plasmodium vivax-VK247 (variant) circumsporozoite (CS) protein was developed and evaluated using sporozoites produced by feeding mosquitoes on Thai patients with parasitologically confirmed P. vivax infections. The ELISA had a detection threshold of fewer than 50 sporozoites. Using this assay in conjunction with an ELISA for the VK210 polymorph, nearly 16% of the 235 P. vivax cases produced sporozoites positive only for the variant; 69% produced sporozoites positive only in the VK210 assay; and 15% were positive in both assays, indicating mixed infections. Twelve cases (5%) produced sporozoites negative in one assay and with unexpectedly low activity in the other ELISA, indicating the possibility of other CS protein polymorphs.
Wirtz
R A
RA
Department of Entomology, Walter Reed Army Institute of Research, Washington, D.C. 20307-5100.
Sattabongkot
J
J
Hall
T
T
Burkot
T R
TR
Rosenberg
R
R
D000595:Amino Acid Sequence; D000818:Animals; D004797:Enzyme-Linked Immunosorbent Assay; D008969:Molecular Sequence Data; D010966:Plasmodium vivax / Q000737:chemistry*