مرکز منطقه ای اطلاع رساني علوم و فناوري -

چكيده لاتين :

It is now well documented that interferon gamma (lFN-y) is the indispensable cytokine for inducing protective immunity against experimental and human cutaneous leishmaniaisis. The importance of IFN-y receptor (lFN-yR) has also been studied. In the present study, we made attempts to find out whether L. major infection is able to alter the expression of IFN-yR in vivo. In addition, we studied the responsiveness to IFN-y ex vivo. To do that, we assessed the expr ession of CD119 (IFN-yRa.) on CD45+ cells isolated from draining lymph nodes of infected and uninfected BALB/c and C57BLl6 mice by flow cytometry. The MFI (mean fluorescence intensities) of CD119 on uninfected BALB/c mice were 192.8 ± 18.4 but the CD119 MFI of infected BALB/c mice were remarkably decreased (107.9±40.8). CD1l9 MFI of uninfected and infected C57BLl6 mice wenי 276.2 ± 17.1 and 140.4±43.0 respectively Moreover, we measured the production of nitric oxide (NO) hy these cells in th e presence of IFN-y in order to study the function of IFN-yR. NO production by draining lymph nodes cells of infected C57BLl6 mice in response to recombinant murine IFN-y was significantly higher than the cells of infected BALB/c mice (37.5 ± 0.6 and 11.6 ± 0.5 JlM respectively, p<0 .05). Therefore, our results confirm the in vitro reports regarding the impairment of IFN-y responsiveness due to Leishmania infection. Iran. Biom ed. 1. 10 (2) : 105-109. 2006