Intracellular localization of MyosinXXI discriminates Leishmania spp and Leptomonasseymouri

The patients with the most dreaded Leishmania donovani infections are now regularly been detected with co-infecting monoxenous trypanosomatid, Leptomonas seymouri, of which pathological consequence is obscure. Due to high degree of morphological similarity, its presence remains unmarked in the culture which leads to anomalous research outcomes. The available methods to detect Leptomonas in cultures are cumbersome and are not quantitative. We report here that MyosinXXI serves as a distinguishing biomarker that can be used to mark the presence of L. seymouri in Leishmania cultures. The method uses Leishmania MyosinXXI antibodies employed in immunofluorescence microscopy that shows a specialized localization pattern in Leishmania but not in Leptomonas (Patent application No. IN201711014439). This method is not only qualitative, but can also quantify the L. seymouri load in the cultured field isolates and serves as a remarkable tool to ascertain laboratory strains of Leishmania.