Anti-PSG3 monoclonal antibody Made to order

Cell-cell fusion is an essential event during life. Throughout human pregnancy, the syncytiotrophoblast (STB) layer of the placenta is formed by continuous fusion of the underlying villous cytotrophoblasts, thus maintaining placental functionality. Defects in this process are associated with pathologies like pre-eclampsia and intrauterine growth restriction. Kruppel-like factor 6 (KLF6) is a transcription factor highly expressed in human and murine placenta. However, KLF6 functions in trophoblast cells remain largely unexplored. The aim of this work was to address the role of KLF6 during STB formation. KLF6 knockdown through small interfering RNA experiments hindered cell-cell fusion revealed by immunofluorescence microscopy in human primary villous cytotrophoblast as well as in the human placental-derived BeWo cell line. Furthermore, KLF6 silencing led to a decrease in the expression of the fusogenic protein Syncytin-1 and the cell cycle regulator p21(Cip1/Waf1)measured by quantitative RT-PCR and western blot assays. On the contrary, transcript levels of genes that encode for proteins involved in STB formation such as Syncytin-1, Syncytin-2, Connexin-43 and Zonula Occludens-1 increased when KLF6 was overexpressed in differentiating villous cytotrophoblasts and in non-fusing placental-derived JEG-3 cells. Interestingly, the expression of two trophoblast biochemical differentiation markers, beta hCG and PSG3, were not reduced after KLF6 silencing in differentiating trophoblast cells. Present results support the notion that KLF6 is a relevant participant in cytotrophoblast fusion.

Vibrio vulnificus is an opportunistic pathogen that causes septicerma in humans. To identify the genes associated with its pathogenicity, in vivo expression technology (IVET) was used to select genes specifically expressed in a host, yet not significantly in vitro. Random locZ-fusions the genome of V vulnficus strain MO6-24/O were constructed using an IVET vector, pSG3, which is a suicide vector containing promoterless-aph and -lacZ as reporter genes. A total of similar to 18,000 resulting library clones were then intraperitoneally injected into BALB/c mice using a colony forming unit (CFU) of 1.6 x 10(6). Two hours after infection, kanamycin was administered at 200 mu g per gram of mouse weight. After two selection cycles, 11 genes were eventually isolated, which were expressed only in the host. Among these genes, VV20781 and VV21007 exhibiting a homology to a hemagglutinin gene and tolC, respectively, were selected based on having the highest frequency. When compared to wild-type cells, mutants with lesions in these genes showed no difference in the rate of growth rate, yet a significant decrease in cytotoxicity and the capability to form a biofilm.