Browsing by keyword "Chemokine CXCL10"

Now showing items 1-3 of 3

    • Cryptococcosis-IRIS is associated with lower cryptococcus-specific IFN-gamma responses before antiretroviral therapy but not higher T-cell responses during therapy
      Chang, Christina C.; Lim, Andrew; Omarjee, Saleha; Levitz, Stuart M.; Gosnell, Bernadett I.; Spelman, Tim; Elliott, Julian H.; Carr, William H.; Moosa, Mohamed-Yunus S.; Ndung'u, Thumbi; et al. (2013-09-01)
      BACKGROUND: Cryptococcosis-associated immune reconstitution inflammatory syndrome (C-IRIS) may be driven by aberrant T-cell responses against cryptococci. We investigated this in human immunodeficiency virus (HIV)-infected patients with treated cryptococcal meningitis (CM) commencing combination antiretroviral therapy (cART). METHODS: Mitogen- and cryptococcal mannoprotein (CMP)-activated (CD25+CD134+) CD4+ T cells and -induced production of interferon-gamma (IFN-gamma), IL-10, and CXCL10 were assessed in whole blood cultures in a prospective study of 106 HIV-CM coinfected patients. RESULTS: Patients with paradoxical C-IRIS (n = 27), compared with patients with no neurological deterioration (no ND; n = 63), had lower CMP-induced IFN-gamma production in 24-hour cultures pre-cART and 4 weeks post-cART (P = .0437 and .0257, respectively) and lower CMP-activated CD4+ T-cell counts pre-cART (P = .0178). Patients surviving to 24 weeks had higher proportions of mitogen-activated CD4+ T cells and higher CMP-induced CXCL10 and IL-10 production in 24-hour cultures pre-cART than patients not surviving (P = .0053, .0436 and .0319, respectively). C-IRIS was not associated with higher CMP-specific T-cell responses before or during cART. CONCLUSION: Greater preservation of T-cell function and higher CMP-induced IL-10 and CXCL10 production before cART are associated with improved survival while on cART. Lower CMP-induced IFN-gamma production pre-cART, but not higher CMP-specific T-cell responses after cART, were risk factors for C-IRIS.

    • SARM regulates CCL5 production in macrophages by promoting the recruitment of transcription factors and RNA polymerase II to the Ccl5 promoter
      Gurtler, Claudia; Carty, Michael; Kearney, Jay; Schattgen, Stefan A.; Ding, Aihao; Fitzgerald, Katherine A.; Bowie, Andrew G. (2014-05-15)
      The four Toll/IL-1R domain-containing adaptor proteins MyD88, MAL, TRIF, and TRAM are well established as essential mediators of TLR signaling and gene induction following microbial detection. In contrast, the function of the fifth, most evolutionarily conserved Toll/IL-1R adaptor, sterile alpha and HEAT/Armadillo motif-containing protein (SARM), has remained more elusive. Recent studies of Sarm(-/-) mice have highlighted a role for SARM in stress-induced neuronal cell death and immune responses in the CNS. However, whether SARM has a role in immune responses in peripheral myeloid immune cells is less clear. Thus, we characterized TLR-induced cytokine responses in SARM-deficient murine macrophages and discovered a requirement for SARM in CCL5 production, whereas gene induction of TNF, IL-1beta, CCL2, and CXCL10 were SARM-independent. SARM was not required for TLR-induced activation of MAPKs or of transcription factors implicated in CCL5 induction, namely NF-kappaB and IFN regulatory factors, nor for Ccl5 mRNA stability or splicing. However, SARM was critical for the recruitment of transcription factors and of RNA polymerase II to the Ccl5 promoter. Strikingly, the requirement of SARM for CCL5 induction was not restricted to TLR pathways, as it was also apparent in cytosolic RNA and DNA responses. Thus, this study identifies a new role for SARM in CCL5 expression in macrophages.

    • Virus-cell fusion as a trigger of innate immunity dependent on the adaptor STING
      Holm, Christian K.; Jensen, Soren B.; Jakobsen, Martin R.; Cheshenko, Natalia; Horan, Kristy A.; Moeller, Hanne B.; Gonzalez-Dosal, Regina; Rasmussen, Simon B.; Christensen, Maria H.; Yarovinsky, Timur O.; et al. (2012-06-17)
      The innate immune system senses infection by detecting either evolutionarily conserved molecules essential for the survival of microbes or the abnormal location of molecules. Here we demonstrate the existence of a previously unknown innate detection mechanism induced by fusion between viral envelopes and target cells. Virus-cell fusion specifically stimulated a type I interferon response with expression of interferon-stimulated genes, in vivo recruitment of leukocytes and potentiation of signaling via Toll-like receptor 7 (TLR7) and TLR9. The fusion-dependent response was dependent on the stimulator of interferon genes STING but was independent of DNA, RNA and viral capsid. We suggest that membrane fusion is sensed as a danger signal with potential implications for defense against enveloped viruses and various conditions of giant-cell formation.