Interferon (IFN) exhibits a potent antiviral activity in vitro and plays a major role in the early defense against viruses. Like IFN, the proinflammatory chemokine, interleukin (IL)-8, is induced by viruses and appears in circulation during viral infections. In an in vitro cytopathic effect assay for IFN, we found that IL-8 can inhibit IFN-α activity in a dose-dependent manner. This action was reversed by specific monoclonal antibodies to IL-8. The chemokine was able to attenuate the IFN-mediated inhibition of viral replication as determined by measuring infectious virus yield. IL-8 also diminished the ability of IFN to inhibit an early stage of viral replication since IL-8 attenuated the inhibition of the formation of viral proteins. It appeared that IL-8 interfered with a late rather than an early step of IFN-mediated pathway such as early gene expression. The IL-8 inhibitory action on IFN-α antiviral activity was associated with reduced 2′,5′-A oligoadenylate synthetase activity, a pathway well correlative with the anti– encephalomyocarditis virus action of IFN-α. Understanding pathways that antagonize IFN action may lead to novel approaches to potentiate endogenous and therapeutic IFN.

MTS, a tetrazolium dye, is reduced by hydrogenases in living cells to a water-soluble formazan. When it is added to the medium at the end of a cytopathic effects (CPE) inhibition interferon assay, the formazan formed diffuses into the medium; the resultant optical density directly and quantitatively measures how much cellular damage has been produced by the challenge virus in the presence of different amounts of interferon. The use of MTS has considerable advantages in that after it is added, no further steps, such as washing of the cells, extraction of dye, or other manipulations, are needed.

PURPOSE.The French Canadian population of Quebec is a unique, well-known founder population with religious, linguistic, and geographic isolation. The genetics of retinitis pigmentosa (RP) in Quebec is not well studied thus far. The purpose of our study was to establish the genetic architecture of autosomal dominant RP (adRP) and to characterize the phenotypes associated with new adRP mutations in Quebec.METHODS. Sanger sequencing of the commonly mutated currently known adRP genes was performed in a clinically well-characterized cohort of 60 adRP French Canadian families. Phenotypes were analyzed by projected visual acuity (best corrected), Goldmann visual fields, optical coherence tomography (OCT), fundus autofluorescence (FAF), and ERG. The potential effect of the novel mutations was assessed using in silico bioinformatic tools. The pathogenicity of all variants was then confirmed by segregation analysis within the families, when available. RESULTS.We identified the causal mutation/gene in 24 of our adRP families, as 24 (40%) of 60 patients had adRP mutations in six known adRP genes. Eleven (46%) of these mutations were in RHO, four mutations (17%) were found in SNRNP200, three mutations (12.5%) in PRPH2/RDS, three mutations (12.5%) in TOPORS, two mutations (8%) in PRPF31, and one mutation (4%) in IMPDH1. Four mutations were novel. We identified new mutations in RHO (p.S270I), PRPF31 (p.R288W), IMPDH1 (p.Q318H), and TOPORS (p.H889R); the rest were previously reported. We present the genotype-phenotype characteristics of the four novel missense mutations.CONCLUSIONS. This is the first large screening of adRP genes in the founder population of Quebec. Our prevalence of known adRP genes is 40% in the French Canadian population, which is lower than in other adRP populations around the world, illustrating the uniqueness of the French Canadian population. Our findings are crucial in expanding the current understanding of the genotypic-phenotypic spectrum of RP and documenting the genetic architecture of our founder population.

Background: NK cell-based immunotherapy to prevent relapse after allogeneic transplantation is an appealing strategy because NK cells can provide strong antitumor effect without inducing graft-versus-host disease (GVHD). Thus, we designed a phase-I clinical trial evaluating the safety of a prophylactic donor-derived ex vivo IL-2 activated NK cell (IL-2 NK) infusion after allo-HSCT for patients with hematologic malignancies. Methods: Donor NK cells were purified and cultured ex vivo with IL-2 before infusion, at three dose levels. To identify the maximum tolerated dose was the main objective. In addition, we performed phenotypical and functional characterization of the NK cell therapy product, and longitudinal immune monitoring of NK cell phenotype in patients. Results: Compared to unstimulated NK cells, IL-2 NK cells expressed higher levels of activating receptors and exhibited increased degranulation and cytokine production in vitro. We treated 16 patients without observing any dose-limiting toxicity. At the last follow up, 11 out of 16 treated patients were alive in complete remission of hematologic malignancies without GVHD features and immunosuppressive treatment. Conclusions: Prophylactic donor-derived IL-2 NK cells after allo-HSCT is safe with low incidence of GVHD. Promising survivals and IL-2 NK cell activated phenotype may support a potential clinical efficacy of this strategy.

Ewing's Sarcoma transcript-2 (EAT2) also known as SH2D1B is involved in regulation of signalling lymphocytic activation molecule (SLAM) family receptor functions. Cytoplasmic tails of SLAM family receptors contain tyrosine residues which mediate the downstream signal transduction through their phosphorylation. EAT2, composed of a single SH2 domain and a short C-terminal tail, binds to the phosphotyrosine residues and regulates SLAM family receptor signalling. We have determined the crystal structure of the human EAT2 protein in an unliganded form. Compared with the mouse EAT2-peptide complex structure, we observe conformational differences in the loops involved in ligand binding. When compared with SAP, the other single SH2 domain protein in human, EAT2 shows similar binding energies to unphosphorylated ligands. This is inconsistent to the previous data showing low affinity of EAT2 toward unphosphorylated peptides compared to SAP which shows high affinity. Additional factors other than the SH2 domains may contribute to the reported differences.

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High levels of circulating immunoglobulin G (IgG) and serum albumin (SA) are maintained through recycling by the neonatal Fc receptor (FcRn). FcRn interacts with IgG and SA in a pHdependent manner and rescues them from lysosomal degradation. We have determined the crystal structure of extracellular domain of human FcRn, a heterodimeric complex of α-chain and β2- microglobulin, at pH 4.5. The structure was compared with the previously reported unliganded human FcRn structure at pH 8.5 and complex structures of FcRn bound to SA and/or Fc determined at acidic pHs. Structural differences are more pronounced between the two unliganded FcRn structures at pH 4.5 and pH 8.5 than between unliganded FcRn and the complex structures at acidic pHs. At acidic pH, protonation of H166 induces interactions with E54 and Y60 stabilizing the "WW loop" important for SA binding, and H161 interacts with E165 causing conformational changes of helix 3. These structural changes make the FcRn amenable for binding with SA at acidic pH. The Fc binding surface does not show any major main chain differences between the unliganded structures at pH 8.5 and pH 4.5. Side chain changes upon Fc binding were observed when compared with the complex structures. This suggests that major structural differences observed between unliganded and ligand bound structures are primarily due to pH changes rather than ligand binding.

Pseudomonas aeruginosa was isolated from fifty soil samples were collected from different sites of contaminated soil with oil residues in Ministry of science& technology. Morphological, biochemical tests and 16S rRNA genes sequencing was performed for bacterial isolates identification. Thirty (30) isolates of P. aeruginosa bacteria were confirmed according to morphological, biochemical tests. For molecular analysis, all isolates that tested positive for P. aeruginosa underwent amplification of the 16S rRNA gene using previously described primers that amplified a particular DNA fragment of 956 bp. PCR product was delivered to Macrogen Corporation - Korea for Sanger sequencing utilizing an automated DNA sequencer called the ABI3730XL. The results were emailed to us, and we used geneious software to analyze them. The investigation of phylogenetic relationships between different strains of Pseudomonas aeruginosa has frequently been conducted on the sequencing of the 16S rRNA gene region, which is a viable technique for species identification. To determine the degree of genetic similarity between the organisms, a distance tree was built. Consequently, gene sequencing of the 16S rRNA region was an appropriate method for isolating isolates at the molecular level. The a novel local strain of Ps. aeruginosa which isolated from contaminated soil with oil residues samples (MSZ. IRQ20) and we will registration of isolate in GenBank under accession number of MT832126.1. Distance Tree Using Blast Tool in the Geneious software.