The current configuration of the OptiMAL(R) immuno-assay for malaria relies on antibodies generated to P. falciparum LDH. Some of these antibodies recognize all species of human malaria while others are more selective recognizing the falciparum pLDH isoforms specifically. These antibodies when used in combination can differentiate between P. falciparum and non-falciparum malaria. However, accurate and simple discrimination between P. vivax, P. malariae or P.ovalae is not readily available. We propose to: 1) Obtain the pLDH gene from P. vivax, P. malariae and P. ovalae. 2) Produce the corresponding pLDH proteins recombinantly in bacteria. 3) Produce monoclonal antibodies that recognize native pLDH from P. vivax P. ovalae and P. malariae that do not cross react with P. falciparum or the human LDH isoforms. 4) Assemble a prototype diagnostic immunochromatographic test strip using these new specific antibodies and test their performance under laboratory conditions. 5) Test the new prototype immunochromatographic test under laboratory/field conditions. PROPOSED COMMERCIAL APPLICATIONS: They extend the capability of the original OptiMAL(R) assay and allow introduction of new and improved products. May help better determination of antimalarial therapy, given the rise of drug resistant P. vivax but not P.ovalae or P. malariae. Antibodies may be produced that have even a better sensitivity then the ones currently used in the current version of the OptiMAL(R) diagnostic assay.