A comparative analysis of saponin-enriched fraction from Silene vulgaris (Moench) Garcke, Sapindus mukorossi (Gaertn) and Chlorophytum borivilianum (Santapau and Fernandes): an in vitro hemolytic and cytotoxicity evaluation.

To explore the newer saponin resources, in vitro toxicity of saponin-enriched fraction (SEF) extracted from Silene vulgaris(SV) was evaluated for first time and compared with in vitro toxicity of SEF extracted from Sapindus mukorossi (SM) and Chlorophytum borivilianum (CV). All extracted SEF from diverse resources were characterized by immersing TLC plates in 0.5% RBC suspension method, by ethanol: sulfuric acid method and by estimating hRst values. Each extracted SEF clearly portrayed specific pattern with varied hRst range. White spots against a pinkish-red background and greenish-black spots in case of immersion method and spraying method respectively were observed. After initial characterization, in vitro 0.5% sheep RBC lytic activities and VERO cell cytotoxic activities (via SRB assay) of each extracted SEF were also evaluated. Furthermore, SEF of SV showed very less hemolytic activity compared to SM and CB. The HD50 values for SV, SM, and CB were 736.7 ± 2.824, 18.0 ± 1.894, and 170.70 ± 2.783 µg/mL, respectively. SEF of SV (IC50 ≥ 200 µg/mL) was less toxic for VERO cell line than SEF of SM (IC50 = 150.8 µg/mL) and CB (IC50 = 137.1 µg/mL). Hence, the SEF of SV was found to be less toxic and can be used as a new and safer source of saponins.

The domesticated buffalo - An emerging model for experimental and therapeutic use of extraembryonic tissues.

Large animals play important roles as model animals for biomedical sciences and translational research. The water buffalo (Bubalus bubalis) is an economically important, multipurpose livestock species. Important assisted reproduction techniques, such as in vitro fertilization, cryo-conservation of sperm and embryos, embryo transfer, somatic cell nuclear transfer, genetic engineering, and genome editing have been successfully applied to buffaloes. Recently, detailed whole genome data and transcriptome maps have been generated. In addition, rapid progress has been made in stem cell biology of the buffalo. Apart from embryonic stem cells, bubaline extra-embryonic stem cells have gained particular interest. The multipotency of non-embryonic stem cells has been revealed, and their utility in basic and applied research is currently investigated. In particular, success achieved in bubaline extra-embryonic stem cells may have important roles in experimental biology and therapeutic regenerative medicine. Progress in other farm animals in assisted reproduction techniques, stem cell biology and genetic engineering, which could be of importance for buffalo, will also be briefly summarized.

Structural basis of the binding of fatty acids to peptidoglycan recognition protein, PGRP-S through second binding site.

Short peptidoglycan recognition protein (PGRP-S) is a member of the mammalian innate immune system. PGRP-S from Camelus dromedarius (CPGRP-S) has been shown to bind to lipopolysaccharide (LPS), lipoteichoic acid (LTA) and peptidoglycan (PGN). Its structure consists of four molecules A, B, C and D with ligand binding clefts situated at A-B and C-D contacts. It has been shown that LPS, LTA and PGN bind to CPGRP-S at C-D contact. The cleft at the A-B contact indicated features that suggested a possible binding of fatty acids including mycolic acid of Mycobacterium tuberculosis. Therefore, binding studies of CPGRP-S were carried out with fatty acids, butyric acid, lauric acid, myristic acid, stearic acid and mycolic acid which showed affinities in the range of 10(-5) to 10(-8) M. Structure determinations of the complexes of CPGRP-S with above fatty acids showed that they bound to CPGRP-S in the cleft at the A-B contact. The flow cytometric studies showed that mycolic acid induced the production of pro-inflammatory cytokines, TNF-α and IFN-γ by CD3+ T cells. The concentrations of cytokines increased considerably with increasing concentrations of mycolic acid. However, their levels decreased substantially on adding CPGRP-S.

Distinct roles for tetraspanins CD9, CD63 and CD81 in the formation of multinucleated giant cells.

Members of the tetraspanin superfamily of proteins are implicated in a variety of complex cell processes including cell fusion. However, the contribution of individual tetraspanins to these processes has proved difficult to define. Here we report the use of recombinant extracellular regions of tetraspanins to investigate the role of specific members of this family in the fusion of monocytes to form multinucleated giant cells (MGC). In contrast to their positive requirement in sperm-egg fusion, previous studies using antibodies and knockout mice have indicated a negative regulatory role for tetraspanins CD9 and CD81 in this process. In an in vitro model of fusion using human monocytes, we have confirmed observations that antibodies to CD9 and CD81 enhance MGC formation; however, in contrast to previous investigations, we found that all members of a panel of antibodies to CD63 inhibited fusion. Moreover, recombinant proteins corresponding to the large extracellular domains (EC2s) of CD63 and CD9 inhibited MGC formation, whereas the EC2s of CD81 and CD151 had no effect. The potent inhibition of fusion and binding of labelled CD63 EC2 to monocytes under fusogenic conditions suggest a direct interaction with a membrane component required for fusion. Our findings indicate that the tetraspanins CD9, CD63 and CD81 are all involved in MGC formation, but play distinct roles.