Risk of mother-to-child transmission of Toxoplasma gondii during pregnancy is much greater in women who are exposed to primary T. gondii infection (toxoplasmosis) after conception compared to those who were exposed to the infection before conception. Therefore, laboratory tests that help classify recent primary toxoplasmosis are important tools for the management of pregnant women suspected to have T. gondii exposure. Detection of Toxoplasma IgM (Toxo IgM) is a sensitive indicator of primary toxoplasmosis, but the indicator specificity is low because sometimes natural IgM antibodies react with Toxoplasma antigens in the absence of the infection.

The mainstay therapy against leishmaniasis is still pentavalent antimonial drugs; however, the rate of antimony resistance is increasing in endemic regions such as Iran. Understanding the molecular basis of resistance to antimonials could be helpful to improve treatment strategies. This study aimed to recognize genes involved in antimony resistance of Leishmania tropica field isolates. Sensitive and resistant L. tropica parasites were isolated from anthroponotic cutaneous leishmaniasis patients and drug susceptibility of parasites to meglumine antimoniate (Glucantime®) was confirmed using in vitro assay. Then, complementary DNA-amplified fragment length polymorphism (cDNA-AFLP) and real-time reverse transcriptase-PCR (RT-PCR) approaches were utilized on mRNAs from resistant and sensitive L. tropica isolates. We identified 2 known genes, ubiquitin implicated in protein degradation and amino acid permease (AAP3) involved in arginine uptake. Also, we identified 1 gene encoding hypothetical protein. Real-time RT-PCR revealed a significant upregulation of ubiquitin (2.54-fold), and AAP3 (2.86-fold) (P<0.05) in a resistant isolate compared to a sensitive one. Our results suggest that overexpression of ubiquitin and AAP3 could potentially implicated in natural antimony resistance.