Application of the Leishmania infantum 21-kDa recombinant protein for the development of an immunochromatographic test.

BACKGROUND: Visceral leishmaniasis (VL), caused by Leishmania infantum, is a systemic parasitic disease and presents a global health problem which can be fatal if not diagnosed and treated. Dogs are the main hosts and provide reservoirs for the transmission of the disease to humans. METHODS: In this study, the gene encoding a 21-kDa protein was cloned and expressed as a fusion protein in Escherichia coli strain BL21 (DE3) for developing a rapid immunochromatographic test (ICT) to identify infected dogs. The expression of the recombinant 21-kDa protein (r21) was investigated using SDS-PAGE and Western blot methods. The purified r21-kDa protein was spotted onto ICT strips and tested by sera from experimentally infected, naturally infected and uninfected dogs. RESULTS: The SDS-PAGE and Western blot methods showed the successful expression of r21-kDa protein. The ICT strip test revealed that the r21-kDa protein was detected by the sera of experimentally and naturally infected dogs. The specificity tests also confirmed no cross-reactivity with animals infected with Trypanosoma cruzi, Toxoplasma gondii and Ehrlichia canis. CONCLUSIONS: Based on these findings, the new r21-kDa protein may be a suitable target for developing a new simple, specific and rapid serological method to detect VL in infected dogs.

Anxiety leads to up-regulation of CD36 on the monocytes of chronic hepatitis B-infected patients.

Introduction It has been hypothesized that mental disorders including depression and anxiety can affect immune responses. The study was done to evaluate the relation between depression and anxiety and expression levels of CD36, CD68, and CD9 on peripheral blood monocytes of chronic hepatitis B (CHB) patients. Methods Sixty CHB patients were selected with various ranges of depression and anxiety. Depression and anxiety were evaluated using a standard questionnaire by an expert psychiatrist according to BECK's Depression Inventory II and Hamilton Anxiety Rating Scale, respectively. The levels of CD36, CD68, and CD9 on the peripheral blood monocytes have been performed using flow cytometry technique. Results The results demonstrated that levels of CD36 were significantly increased on the peripheral blood monocytes of CHB patients when compared with CHB patients with no anxiety. Expression levels of CD68 and CD9 were not significantly altered on the CHB patients with various ranges of anxiety. Expression levels of CD36, CD68, and CD9 were also not significantly altered on the CHB patients with various ranges of depression. Discussion It seems that anxiety induces inflammation in the CHB patients by induction of alteration in several molecules including up-regulation of CD36. CD36 plays important roles in the induction of tissue damage; hence, it may be hypothesized that anxiety may participate in the induction of some hepatitis B complications.