Measurement of Bottom versus Charm as a Function of Transverse Momentum with Electron-Hadron Correlations in p+p Collisions at sqrt(s)=200 GeV

The momentum distribution of electrons from semi-leptonic decays of charm and bottom for mid-rapidity |y|<0.35 in p+p collisions at sqrt(s)=200 GeV is measured by the PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) over the transverse momentum range 2 < p_T < 7 GeV/c. The ratio of the yield of electrons from bottom to that from charm is presented. The ratio is determined using partial D/D^bar --> e^{+/-} K^{-/+} X (K unidentified) reconstruction. It is found that the yield of electrons from bottom becomes significant above 4 GeV/c in p_T. A fixed-order-plus-next-to-leading-log (FONLL) perturbative quantum chromodynamics (pQCD) calculation agrees with the data within the theoretical and experimental uncertainties. The extracted total bottom production cross section at this energy is \sigma_{b\b^bar}= 3.2 ^{+1.2}_{-1.1}(stat) ^{+1.4}_{-1.3}(syst) micro b.Comment: 432 authors, 6 pages text, 3 figures. Submitted to Phys. Rev. Lett. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at http://www.phenix.bnl.gov/papers.htm

Role of CXC chemokine receptor 3 pathway in renal ischemic injury

Chemokines play a major role in the recruitment of leukocytes in inflammation and in the regulation of T helper 1 (Th1)/Th2 immune responses. These mechanisms have been recognized to be important in the pathogenesis of renal ischemia-reperfusion (I/R) injury. The interaction of the CXC chemokine receptor 3 (CXCR3) receptor with its ligands is a key pathogenic pathway in promoting inflammation and in enhancing Th1 immune responses. After the induction of ischemia in the mouse model of renal ischemia, an increase in intrarenal expression of CXCR3 and its ligands was observed. Compared with the wild-type (WT) mice, CXCR3-deficient mice (CXCR3-/-) had significantly lower serum creatinine levels, better survival rate, and significantly less acute tubular necrosis and cellular infiltrates. In the kidney, intracellular staining of infiltrating cells that were recovered from kidneys revealed a lower percentage of CD4+IFN-\u3b3+ cells in the CXCR3-/- mice compared with the WT mice. Furthermore, adoptive transfer of WT CD3+ cells into CXCR3-/- mice before induction of I/R injury abrogated the protection of CXCR3-/- mice from I/R injury. It is concluded that CXCR3 plays an important role in orchestrating the recruitment of Th1 cells to the ischemic kidney and in mediating I/R injury and therefore may serve as a novel target for the therapy of I/R injury

Ubiquitin Ligase TRIM62 Regulates CARD9-Mediated Anti-fungal Immunity and Intestinal Inflammation

Contains fulltext : 152899.pdf (Publisher’s version ) (Closed access)CARD9 is a central component of anti-fungal innate immune signaling via C-type lectin receptors, and several immune-related disorders are associated with CARD9 alterations. Here, we used a rare CARD9 variant that confers protection against inflammatory bowel disease as an entry point to investigating CARD9 regulation. We showed that the protective variant of CARD9, which is C-terminally truncated, acted in a dominant-negative manner for CARD9-mediated cytokine production, indicating an important role for the C terminus in CARD9 signaling. We identified TRIM62 as a CARD9 binding partner and showed that TRIM62 facilitated K27-linked poly-ubiquitination of CARD9. We identified K125 as the ubiquitinated residue on CARD9 and demonstrated that this ubiquitination was essential for CARD9 activity. Furthermore, we showed that similar to Card9-deficient mice, Trim62-deficient mice had increased susceptibility to fungal infection. In this study, we utilized a rare protective allele to uncover a TRIM62-mediated mechanism for regulation of CARD9 activation

Linking indirect effects of cytomegalovirus to modulation of monocyte innate immune function

Cytomegalovirus (CMV) is an important cause of morbidity and mortality in the immunocompromised host. In transplant recipients, a variety of clinically important "indirect effects" are attributed to immune modulation by CMV, including increased mortality from fungal disease, allograft dysfunction and rejection in solid organ transplantation, and graft-versus-host-disease in stem cell transplantation. Monocytes, key cellular targets of CMV, are permissive to primary, latent and reactivated CMV infection. Here, pairing unbiased bulk and single cell transcriptomics with functional analyses we demonstrate that human monocytes infected with CMV do not effectively phagocytose fungal pathogens, a functional deficit which occurs with decreased expression of fungal recognition receptors. Simultaneously, CMV-infected monocytes upregulate antiviral, pro-inflammatory chemokine, and inflammasome responses associated with allograft rejection and graft-versus-host disease. Our study demonstrates that CMV modulates both immunosuppressive and immunostimulatory monocyte phenotypes, explaining in part, its paradoxical "indirect effects" in transplantation. These data could provide innate immune targets for the stratification and treatment of CMV disease.</p

Suppression of GSK3β by ERK mediates lipopolysaccharide induced cell migration in macrophage through β-catenin signaling

We investigate the role of β-catenin signaling in the response of macrophage to lipopolysaccharide (LPS) using RAW264.7 cells. LPS rapidly stimulated cytosolic β-catenin accumulation. β-catenin-mediated transcription was showed to be required for LPS induced gene expression and cell migration. Mechanically, ERK activation-primed GSK3β inactivation by Akt was demonstrated to mediate the LPS induced β-catenin accumulation. Overall, our findings suggest that suppression of GSK3β by ERK stimulates β-catenin signaling therefore contributes to LPS induced cell migration in macrophage activation