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Bovine Cells (bovine + cell)
Selected AbstractsDifferent apoptotic responses of human and bovine pericytes to fluctuating glucose levels and protective role of thiamineDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 6 2009Elena Beltramo Abstract Background Vascular cells in diabetes are subjected to daily fluctuations from high to low glucose. We aimed at investigating whether pulsed exposure to different glucose concentrations influences apoptosis in human retinal pericytes (HRP) versus bovine retinal pericytes (BRP), with consequences on the onset of diabetic retinopathy, and the possible protective role of thiamine. Methods BRP and HRP (wild-type and immortalized) were grown in physiological/high glucose for 7 days, and then returned to physiological glucose for another 24, 48 or 72 h. Cells were also kept intermittently at 48-h intervals in high/normal glucose for 8 days, with/without thiamine/benfotiamine. Apoptosis was determined through ELISA, TUNEL, Bcl-2, Bax and p53 expression/concentration. Results Continuous exposure to high glucose increased apoptosis in BRP, but not HRP. BRP apoptosis normalized within 24 h of physiological glucose re-entry, while HRP apoptosis increased within 24,48 h of re-entry. Intermittent exposure to high glucose increased apoptosis in HRP and BRP. Bcl-2/Bax results were consistent with DNA fragmentation, while p53 was unchanged. Thiamine and benfotiamine countered intermittent high glucose-induced apoptosis. Conclusions Human pericytes are less prone to apoptosis induced by persistently high glucose than bovine cells. However, while BRP recover after returning to physiological levels, HRP are more vulnerable to both downwardly fluctuating glucose levels and intermittent exposure. These findings reinforce the hypotheses that (1) glycaemic fluctuations play a role in the development of diabetic retinopathy and (2) species-specific models are needed. Thiamine and benfotiamine prevent human pericyte apoptosis, indicating this vitamin as an inexpensive approach to the prevention and/or treatment of diabetic complications. Copyright © 2009 John Wiley & Sons, Ltd. [source] Cloning and characterization of an immunoglobulin A Fc receptor from cattleIMMUNOLOGY, Issue 2 2004H. Craig Morton Summary Here, we describe the cloning, sequencing and characterization of an immunoglobulin A (IgA) Fc receptor from cattle (bFc,R). By screening a translated EST database with the protein sequence of the human IgA Fc receptor (CD89) we identified a putative bovine homologue. Subsequent polymerase chain reaction (PCR) amplification confirmed that the identified full-length cDNA was expressed in bovine cells. COS-1 cells transfected with a plasmid containing the cloned cDNA bound to beads coated with either bovine or human IgA, but not to beads coated with bovine IgG2 or human IgG. The bFc,R cDNA is 873 nucleotides long and is predicted to encode a 269 amino-acid transmembrane glycoprotein composed of two immunoglobulin-like extracellular domains, a transmembrane region and a short cytoplasmic tail devoid of known signalling motifs. Genetically, bFc,R is more closely related to CD89, bFc,2R, NKp46, and the KIR and LILR gene families than to other FcRs. Moreover, the bFc,R gene maps to the bovine leucocyte receptor complex on chromosome 18. Identification of the bFc,R will aid in the understanding of IgA,Fc,R interactions, and may facilitate the isolation of Fc,R from other species. [source] 2,3,7,8-Tetrachlorodibenzo- p -dioxin modifies expression and nuclear/cytosolic localization of bovine herpesvirus 1 immediate-early protein (bICP0) during infectionJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 2 2010Filomena Fiorito Abstract Our previous studies have demonstrated that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) increases Bovine Herpesvirus 1 (BHV-1) replication through a dose-dependent increase in cytopathy and increased viral titer. Furthermore, TCDD was able to trigger BHV-1-induced apoptosis by up-regulating the activation of initiator caspases 8 and 9, as well as of effector caspase 3. Since TCDD activates caspase 3 after 4,h of infection, we have hypothesized an involvement of BHV-1 infected cell protein 0 (bICP0) in this process. Such protein, the major transcriptional regulatory protein of BHV-1, has been shown to indirectly induce caspase 3 activation and apoptosis. In order to elucidate the role of bICP0 in this apoptotic pathway, here we have analyzed the effects of TCDD on bICP0 expression. Following infection of bovine cells with BHV-1, we detected apoptotic features already at 12,h after infection, only in TCDD exposed groups. Furthermore, in the presence of different doses of TCDD, we observed a time-dependent modulation and increase of bICP0 gene expression levels, as revealed by RT-PCR analysis. Western blot analysis and immunocytochemistry revealed that TCDD induced an increase of bICP0 protein levels in a dose-dependent manner, compared to unexposed groups. Moreover, Western blot analysis of nuclear and cytosolic fractions of infected cells revealed that TCDD anticipated the presence of bICP0 protein in the cytoplasm. In conclusion, both the increase of replication of BHV-1 and anticipation of BHV-1-induced apoptosis could be the result of a relationship between TCDD and bICP0. J. Cell. Biochem. 111: 333,342, 2010. © 2010 Wiley-Liss, Inc. [source] A Novel In Vitro Model of Canine Malignant HemangioendotheliomaANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2005D. Kühn Introduction and Aim:, Canine malignant haemangioendothelioma is an aggressive neoplasia that affects mostly older dogs of large breeds with a strong predilection for the spleen, liver, heart and skin. The tumour originates in the vascular endothelium and consists of transformed cells forming large and leaky vessel-like structures. Prognosis is poor because surgery and chemotherapy have limited success in prolonging survival times and increasing quality of patients. A new strategy to treat this malignancy could be anti-angiogenic therapy based on the inhibition of proliferation, migration and three-dimensional organization of transformed cells. In order to reduce animal experiments, in vitro -models are required to test the safety and efficacy of anti-angiogenic drugs. So far only few models of angiogenesis are available using mostly human, rodent and bovine cells. Therefore, the aim of our study was to establish an in vitro model of canine haemangioendothelioma. Materials and Methods:, Tumours were collected from dogs during surgery or immediately after euthanasia. Isolation of cells was done from different areas of the tumours and by enzymatic digestion of the tissue. Cells were incubated in culture media with and without endothelial growth factors. Cells were characterized by lectin histochemistry using Dolichos biflorus agglutinin, Ulex europaeus agglutinin and Bandeiraea simplicifolia agglutinin I. Moreover, RT-PCR (polymerase chain reaction) was employed to investigate the expression of vascular endothelial growth factor (VEGF) and its endothelium-specific receptors VEGF-R1 and -R2. Results and Conclusions:, Different populations of cells were isolated and cultured successfully from canine malignant haemangioendothelioma. Cells show characteristics of microvascular endothelial cells of an angiogenic phenotype, i.e. the formation of spheroids and tube-like structures as well as strong labelling for Bandeiraea simplicifolia agglutinin I. Thus, morphological and glycohistochemical results confirm the vascular character of the cells isolated. RT-PCR showed expression of VEGF. However, endothelium-specific VEGF receptors were not expressed. Loss of typical receptors is common in cancer and may correlate with increased tumour dedifferentiation. [source] Infection of bovine cells by the protozoan parasite Theileria annulata modulates expression of the ISGylation systemCELLULAR MICROBIOLOGY, Issue 2 2006Chris A. L. Oura Summary The apicomplexan parasite, Theileria annulata, dedifferentiates and induces continuous division of infected bovine myeloid cells. Re-expression of differentiation markers and a loss of proliferation occur upon treatment with buparvaquone, implying that parasite factors actively maintain the altered status of the infected cell. The factors that induce this unique transformation event have not been identified. However, parasite polypeptides (TashAT family) that are located in the infected leucocyte nucleus have been postulated to function as modulators of host cell phenotype. In this study differential RNA display and proteomic analysis were used to identify altered mRNA and polypeptide expression profiles in a bovine macrophage cell line (BoMac) transfected with TashAT2. One of the genes identified by differential display was found to encode an ubiquitin-like protease (bUBP43) belonging to the UBP43 family. The bUBP43 gene and the gene encoding its ubiquitin-like substrate, bISG15, were expressed at a low level in T. annulata -infected cells. However, infected cells were refractory to induction of elevated bISG15 expression by lipopolysaccharide or type 1 interferons while TashAT2 -transfected cells showed no induction when treated with camptothecin. Modulation of the ISGylation system may be of relevance to the establishment of the transformed infected host cell, as ISGylation is associated with resistance to intracellular infection by pathogens, stimulation of the immune response and terminal differentiation of leukaemic cells. [source] | |||||||||||||