Ophidiomycosis is an emerging infectious disease caused by the fungus Ophidiomyces ophiodiicola, which has been affecting wild and captive snakes in North America, Europe, and Australia. We report 12 cases of suspected ophidiomycosis in captive colubrid snakes in Japan. Pathological and microbiological examinations were performed, and the results confirmed the diagnosis of ophidiomycosis in two snakes, which indicated that the remaining sympatrically raised snakes also had ophidiomycosis since they exhibited similar lesions.
View Article and Find Full Text PDF4-1BB, one of co-stimulatory molecules, is a member of TNF receptor superfamily and expressed on T cells upon TCR ligation. We have shown that 4-1BB is a co-stimulatory molecule enhancing cell cycle progression and inhibiting activation-induced cell death of CD8+ T cells by enhancing TCR signaling pathways. Here, we first report that the cross-linking of 4-1BB increased the expression of IL-13 mRNA and protein, and its secretion apparently via calcineurin, a Ca2+/calmodulin-dependent phosphatase.
View Article and Find Full Text PDFTechniques for modulating immune cells for cancer therapy have been widely studied. One key approach that is being clinically tested is developing tumor-destructive cell-mediated immune responses by regulating co-stimulatory molecules. 4-1BB (CD137), a member of the TNF receptor family, is expressed following activation of T and NK cells.
View Article and Find Full Text PDFCross-linking of 4-1BB, a member of the TNFR family, increased tyrosine phosphorylation of TCR-signaling molecules such as CD3epsilon, CD3zeta, Lck, the linker for activation of T cells, and SH2 domain-containing leukocyte phosphoprotein of 76 kDa (SLP-76). In addition, incubation of activated CD8+ T cells with p815 cells expressing 4-1BBL led to redistribution of the lipid raft domains and Lck, protein kinase C-theta;, SLP-76, and phospholipase C-gamma1 (PLC-gamma1) on the T cell membranes to the areas of contact with the p815 cells and recruitment of 4-1BB, TNFR-associated factor 2, and phospho-tyrosine proteins to the raft domains. 4-1BB ligation also caused translocation of TNFR-associated factor 2, protein kinase C-theta;, PLC-gamma1, and SLP-76 to detergent-insoluble compartments in the CD8+ T cells, and cross-linking of 4-1BB increased intracellular Ca2+ levels apparently by activating PLC-gamma1.
View Article and Find Full Text PDF4-1BB, a T cell co-stimulatory receptor, prolongs the survival and multiplication of CD4 T cells. Cross-linking 4-1BB stimulated expression of the anti-apoptotic genes bcl-XL and bcl-2, as well as of cyclins D2 and E, and inhibited expression of the cyclin-dependent kinase (cdk) inhibitor p27kip1. Ova-activated CD4 T cells of 4-1BB-deficient/DO11.
View Article and Find Full Text PDFThe T cell costimulatory receptor 4-1BB enhances cell cycle progression and proliferation of CD8(+) T cells in both an IL-2-dependent and -independent manner. In these studies, 4-1BB costimulation was shown to increase cyclin D2, D3, and E expression, and concomitantly down-regulate the expression of the cyclin-dependent kinase inhibitor p27(kip1). 4-1BB increases cyclin D2 transcription via mitogen-activated/extracellular signal-regulated kinase-1/2 and LY294002-sensitive phosphatidylinositol 3-kinase (PI3K) signaling pathways.
View Article and Find Full Text PDF4-1BB, a T cell costimulatory receptor, prolongs CD8(+) T cell survival. In these studies, 4-1BB stimulation was shown to increase expression of the antiapoptotic genes bcl-x(L) and bfl-1 via 4-1BB-mediated NF-kappaB activation. This signaling pathway was specifically inhibited by PDTC and was different from the pathways that enhanced CD8(+) T cell proliferation.
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