Nestin, a neuroectodermal stem cell marker, is expressed by bovine sertoli cells

Nestin, an intermediate filament protein is expressed by neuroectodermal stem cells and tumors originating from cells of neuroectodermal and mesenchymal lineages. Nestin expression is prominent in embryos and remains upregulated until 3-6 weeks after birth but is downregulated afterward. Sertoli cells are nucleated somatic cells that are spanned in the seminiferous epithelium and play a critical role in supporting and controlling germ-cell development. In this context, we employed immunocytochemical, Western blot, and Flow cytometric analyses to demonstrate nestin expression in bovine sertoli cells. Immunostaining clearly showed that setoli cells express high levels of nestin, a result which was confirmed by Western blot analysis of purified cells. Intracellular staining of sertoli cells by flow cytometry revealed that around 74 of the cells express this marker. Given the high expression of vimentin by sertoli cells, it is proposed that the expression of nestin in these cells might be required for the formation of stable vimentin/nestin intermediate filament network. In light of these findings, it seems that sertoli cells of mature bull have potentiality of proliferation. © 2010 Springer-Verlag London Limited

Regulatory T Cells in γ Irradiation-Induced Immune Suppression

Sublethal total body γ irradiation (TBI) of mammals causes generalized immunosuppression, in part by induction of lymphocyte apoptosis. Here, we provide evidence that a part of this immune suppression may be attributable to dysfunction of immune regulation. We investigated the effects of sublethal TBI on T cell memory responses to gain insight into the potential for loss of vaccine immunity following such exposure. We show that in mice primed to an MHC class I alloantigen, the accelerated graft rejection T memory response is specifically lost several weeks following TBI, whereas identically treated naïve mice at the same time point had completely recovered normal rejection kinetics. Depletion in vivo with anti-CD4 or anti-CD25 showed that the mechanism involved cells consistent with a regulatory T cell (T reg) phenotype. The loss of the T memory response following TBI was associated with a relative increase of CD4+CD25+ Foxp3+ expressing T regs, as compared to the CD8+ T effector cells requisite for skin graft rejection. The radiation-induced T memory suppression was shown to be antigen-specific in that a third party ipsilateral graft rejected with normal kinetics. Remarkably, following the eventual rejection of the first MHC class I disparate skin graft, the suppressive environment was maintained, with markedly prolonged survival of a second identical allograft. These findings have potential importance as regards the immunologic status of T memory responses in victims of ionizing radiation exposure and apoptosis-inducing therapies

On the nonlinear anelastic behavior of AHSS

It has been widely observed that the loading/unloading behavior of metals which have previously undergone plastic deformation is nonlinear. Furthermore it shows a hysteresis behavior upon further unloading/reloading cycles. The origin of this nonlinearity is attributed to additional dislocation based micro-mechanics which contribute to the total reversible strain, referred to as anelastic strain. Compared to a FE model prediction using only elastic contribution to reversible strain the actual springback will be larger. In this work the unloading behavior of DP800 AHSS is analyzed in detail and a mixed physical-phenomenological model is proposed to describe the observed nonlinearity for different levels of pre-strain. This one dimensional uniaxial model is generalized to a 3D constitutive model incorporating elastic, anelastic and plastic strains. The performance of the model is evaluated by comparing the predicted cyclic unloading/reloading stress-strain curves with the experimental ones. It is shown that by incorporating anelastic behavior in the model the prediction of the cyclic behavior of the material is significantly improved

Detection of intracytoplasmic Th1/Th2 cytokine profiles in patients with sepsis and severe sepsis

Background: Sepsis is the leading cause of death in critically ill patients throughout the world. The incidence is increasing despite the major advances in the development of antimicrobial agents and other supportive treatments. Based on multiple studies, it has been shown that patient outcome depends on Th1 and Th2 cytokine response. Moreover, whenever the Th2 response is predominant, the sepsis is more severe. The aim of this study was to evaluate the correlation between cytokine levels and the severity of sepsis in patients. Methods: A cross-sectional study on the cellular levels of several pro-inflammatory cytokines was carried out in patients with sepsis and severe sepsis. The study included 37 patients (24 men and 13 women), 26 of them had sepsis and 11 had the severe form of sepsis Thirty-seven healthy volunteers served as controls. The average age of the patients was 57 years (±23.3 years), with a range of 21 to 92 years. From the whole blood of the subjects, we separated the monocytes and leukocytes, which were then cultured. Using an ELISA method, we measured levels of IFN- and IL-12 (associated with Th1), and IL-4 and IL-10 (associated with Th2) in the cultured cells with and without cell stimulation. Results: No correlation was found for IFN- production in the cells of patients with sepsis and severe sepsis, regardless of whether the patients had died or survived. However, IL-12 levels were significantly decreased in severe sepsis compared with those of sepsis patients (P=0.048). Furthermore, the cells of expired patients also had significantly decreased IL-12 levels compared with those of surviving patients (P=0.028). We also found that the levels of IFN-, IL-4, and IL-10 were decreased in patients compared with those of controls, which correlated to their production. However, there was no correlation for IL-12 production between the cells of the patients compared with those of the controls. There was also no correlation for cytokine production between men and women with sepsis and in adults compared with that of elderly patients (>55 years old). Conclusion: We have shown that the predominating T helper cell subset in patients with severe sepsis, as well as expired patients, is Th2. In conclusion, the correlation of Th1 cytokine production and progression of sepsis was demonstrated. Most probably IL-12 levels would be significantly lower in patients with severe sepsis and those who expired

Vitamin D3 receptor is expressed in the endometrium of cycling mice throughout the estrous cycle

Objective: To investigate the expression and localization of vitamin D3 receptor (VDR) in reproductive organs of cycling mice. Design: Experimental animal study. Setting: Academic research center. Animal(s): Mature (8 to 12 weeks old) cycling female Balb/c mice. Intervention(s): Reproductive tissue, including endometrium, ovary, and fallopian tubes, were collected at each phase of estrous cycle to examine VDR expression. Main Outcome Measure(s): Expression of VDR messenger (mRNA) was determined by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR). The presence and localization of VDR was assessed by immunohistochemistry, and the intensity of VDR expression was quantified with U.S. National Institutes of Health image-analysis software. Result(s): The VDR mRNA was expressed in the endometrium throughout the estrous cycle. The relative expression of VDR mRNA at the estrus phase was more prominent compared with the other phases. Immunohistochemical analysis revealed that dendritic cells, macrophages, and luminal and glandular epithelial cells of the endometrium, granulosa, and cumulus oophorus cells of the ovary and fallopian epithelial cells strongly express VDR, particularly during the estrus phase. Conclusion(s): Our findings have demonstrated, for the first time, that VDR is present and differentially expressed in murine reproductive organs throughout the estrous cycle. Further studies are required to evaluate the functional immunologic role of VDR. © 2010 American Society for Reproductive Medicine

Defining Molecular Details of the Chemistry of Biofilm Formation by Raman Microspectroscopy

Two protocols that allow for the comparison of Raman spectra of planktonic cells and biofilm formed from these cells in their growth phase have been developed. Planktonic cells are washed and flash-frozen in <1 min to reduce the time for metabolic changes during processing, prior to freeze-drying. Biofilm is formed by standing cells in 50 μL indentations in aluminum foil in an atmosphere of saturated water vapor for 24–48 h. The results for <i>Escherichia coli</i> type K12 cells, which do not readily form biofilm, are compared to those for <i>Staphylococcus epidermidis</i> cells, which prolifically synthesize biofilm. For <i>E. coli</i>, the Raman spectra of the planktonic and biofilm samples are similar with the exception that the spectral signature of RNA, present in planktonic cells, could not be detected in biofilm. For <i>S. epidermidis</i>, major changes occur upon biofilm formation. In addition to the absence of the RNA features, new bands occur near 950 cm^–1 and between 1350 and 1420 cm^–1 that are associated with an increase in carbohydrate content. Unlike the case in <i>E. coli</i> biofilm, the intensity of G base ring modes is reduced in but A and T base ring signatures become more prominent. For <i>S. epidermis</i> in the biofilm’s amide III region, there is evidence of an increase in the level of β-sheet structure accompanied by a decrease in α-helical content. The presence of biofilm is confirmed by microscope-aided photography and, separately, by staining with methyl violet