Anti-FASL monoclonal antibody, clone NGM4 Functional Grade

The rosette nanotubes (RNTs) are a class of biologically inspired, self-assembling, metal-free, hydrophilic nanotubes, which hold tremendous potential as targeted drug delivery vehicles. We investigated the cell signaling events caused by lysine-functionalized RNTs (K-RNT) co-assembled with Arg-Gly-Asp-Ser-Lys-functionalized RNTs (RGDSK-RNT) for induction of inflammation and apoptosis in human adenocarcinoma (Calu-3) cells. When co-assembled in a ratio of 1:10 mu M these composite RNTs (referred to as RGDSK/K-RNTs) rapidly induced phosphorylation of P38 mitogen-activated protein kinase (MAPK) within 2 min. Higher concentrations of RGDSK/K-RNTs (>10:100 mu M) resulted in a P38 MAPK-dependent increase in secretion of TNF-alpha. RGDSK/K-RNTs (1:10-40:400 mu M) also caused a concentration- and P38 MAPK-dependent increase in caspase-3 activity and DNA fragmentation in Calu-3 cells at 18 h of exposure. Over-expression of pro-apoptotic genes including caspase-3, BAK1, CIDEB, TP53BP2, FAS, TNF and FASLG supported pro-apoptotic behaviors of these RNTs. We conclude that RGDSK/K-RNTs induce phosphorylation of P38 MAPK, which regulate secretion of TNF-alpha, activation of caspase-3 and apoptosis in Calu-3 cells. These results suggest that the RNTs could be used as a drug to induce apoptosis in cancer cells or as a versatile platform to deliver a variety of biologically active molecules for cancer therapy. (C) 2009 Elsevier Ltd. All rights reserved.

Background: The causes, modes, biological role and prospective significance of cell death in preimplantation development in humans and other mammals are still poorly understood. Early bovine embryos represent a very attractive experimental model for the investigation of this fundamental and important issue. Methods and Findings: To obtain reference data on the temporal and spatial occurrence of cell death in early bovine embryogenesis, three-dimensionally preserved embryos of different ages and stages of development up to hatched blastocysts were examined in toto by confocal laser scanning microscopy. In parallel, transcript abundance profiles for selected apoptosis-related genes were analyzed by real-time reverse transcriptase-polymerase chain reaction. Our study documents that in vitro as well as in vivo, the first four cleavage cycles are prone to a high failure rate including different types of permanent cell cycle arrest and subsequent non-apoptotic blastomere death. In vitro produced and in vivo derived blastocysts showed a significant incidence of cell death in the inner cell mass (ICM), but only in part with morphological features of apoptosis. Importantly, transcripts for CASP3, CASP9, CASP8 and FAS/FASLG were not detectable or found at very low abundances. Conclusions: In vitro and in vivo, errors and failures of the first and the next three cleavage divisions frequently cause immediate embryo death or lead to aberrant subsequent development, and are the main source of developmental heterogeneity. A substantial occurrence of cell death in the ICM even in fast developing blastocysts strongly suggests a regular developmentally controlled elimination of cells, while the nature and mechanisms of ICM cell death are unclear. Morphological findings as well as transcript levels measured for important apoptosis-related genes are in conflict with the view that classical caspase-mediated apoptosis is the major cause of cell death in early bovine development.