2012 MAY 21 - According to the authors of a study from Suwon, South Korea, "Defensins, a family of antimicrobial peptides, are one of the first lines of host defense. Human beta-defensins (hBD) such as hBD-2 and -3 have anti-HIV activity."
"Previous studies have shown that HIV-1 virion can induce the expression of hBD, although the exact components of HIV-1 virion that are responsible for hBD expression have not yet been elucidated. In this study, we examined the effect of HIV-1 Tat on the expression of hBD in B cells. Stimulation of B cells with HIV-1 Tat protein significantly increased the mRNA and protein levels of hBD-2. HIV-1 Tat also induced the activation of a reporter gene for hBD-2 in a dose-dependent manner in B cells. Pretreatment of B cells with a JNK inhibitor suppressed HIV-1 Tat-induced hBD-2 expression. Pretreatment of B cells with AP-1 inhibitors or NF-kappa B inhibitors led to a decrease in HIV-1 Tat-induced protein and mRNA expression of hBD-2," wrote S.M. Ju and colleagues, Sungkyunkwan University (see also HIV/AIDS).
The researchers concluded: "Taken together, our results indicate that HIV-1 Tat can up-regulate the expression of hBD-2 via JNK-NF-kappa B/AP-1-dependent pathways in human B cells."
Ju and colleagues published their study in Molecules and Cells (Extracellular HIV-1 Tat induces human beta-defensin-2 production via NF-kappaB/AP-1 dependent pathways in human B cells. Molecules and Cells, 2012;33(4):335-341).
For more information, contact S.M. Ju, Sungkyunkwan UniversityDept. of Biol Sci, Coll Nat Sci, Suwon 440746, South Korea.
Publisher contact information for the journal Molecules and Cells is: Korean Soc Molecular & Cellular Biology, 635-4, Yucksam-Dong, Gangnam-Gu, Seoul 135-703, South Korea.