Inflammasome-dependent IFN-γ drives pathogenesis in Streptococcus pneumoniae meningitis.

The pathology associated with Streptococcus pneumoniae meningitis results largely from activation of immune-associated pathways. We systematically investigated the production of IFN subtypes, as well as their influence on pathology, in a mouse model of S. pneumoniae meningitis. Despite the occurrence of a mixed IFN type I/II gene signature, no evidence for production or involvement of type I IFNs in disease progression was found. In contrast, type II IFN (IFN-γ) was strongly induced, and IFN-γ(-/-) mice were significantly protected from severe disease. Using intracellular cytokine staining and targeted cell-depletion approaches, NK cells were found to be the dominant source of IFN-γ. Furthermore, production of IFN-γ was found to be dependent upon ASC and IL-18, indicating that an ASC-dependent inflammasome pathway was responsible for mediating IFN-γ induction. The influence of IFN-γ gene deletion on a range of processes known to be involved in bacterial meningitis pathogenesis was examined. Although neutrophil numbers in the brain were similar in infected wild-type and IFN-γ(-/-) mice, both monocyte recruitment and CCL2 production were less in infected IFN-γ(-/-) mice compared with infected wild-type controls. Additionally, gene expression of NO synthase was strongly diminished in infected IFN-γ(-/-) mice compared with infected controls. Finally, bacterial clearance was enhanced in IFN-γ(-/-) mice, although the underlying mechanism remains unclear. Together, these data suggest that inflammasome-dependent IFN-γ contributes via multiple pathways to pathology during S. pneumoniae meningitis.

The yeast homolog of heme oxygenase-1 affords cellular antioxidant protection via the transcriptional regulation of known antioxidant genes.

Heme oxygenase-1 (HO-1) degrades heme and protects cells from oxidative challenge. This antioxidant activity is thought to result from the HO-1 enzymatic activity, manifested by a decrease in the concentration of the pro-oxidant substrate heme, and an increase in the antioxidant product bilirubin. Using a global transcriptional approach, and yeast as a model, we show that HO-1 affords cellular protection via up-regulation of transcripts encoding enzymes involved in cellular antioxidant defense, rather than via its oxygenase activity. Like mammalian cells, yeast responds to oxidative stress by expressing its HO-1 homolog and, compared with the wild type, heme oxygenase-null mutant cells have increased sensitivity toward oxidants that is rescued by overexpression of human HO-1 or its yeast homolog. Increased oxidant sensitivity of heme oxygenase-null mutant cells is explained by a decrease in the expression of the genes encoding γ-glutamylcysteine synthetase, glutathione peroxidase, catalase, and methionine sulfoxide reductase, because overexpression of any of these genes affords partial, and overexpression of all four genes provides complete, protection to the null mutant. Genes encoding antioxidant enzymes represent only a small portion of the 480 differentially expressed transcripts in heme oxygenase-null mutants. Transcriptional regulation may be explained by the nuclear localization of heme oxygenase observed in oxidant-challenged cells. Our results challenge the notion that HO-1 functions simply as a catabolic and antioxidant enzyme. They indicate much broader functions for HO-1, the unraveling of which may help explain the multiple biological responses reported in animals as a result of altered HO-1 expression.

p16 and pRb immunohistochemical expression increases with increasing tumour grade in mammary phyllodes tumours.

AIMS: Control of cell cycling and proliferation is critical to the development of neoplasia and may play a role in the pathogenesis of phyllodes tumours (PTs). This study aimed to evaluate the immunohistochemical expression of certain proteins from the G(1)/S transition of the cell cycle in a cohort of PTs, to determine their role in tumour pathogenesis and to identify any associations with patient outcome. METHODS AND RESULTS: Sixty-five PTs (34 benign, 23 borderline and eight malignant) diagnosed at a single institution between 1990 and 2006 were analysed. Immunohistochemistry for p16, pRb, cyclin D1 and Ki67 was performed. Expression of the following markers increased significantly with tumour grade: stromal nuclear and cytoplasmic p16 (P = 0.01 and 0.002, respectively), stromal and epithelial pRb (P = 0.000,000,06 and 0.004, respectively), and stromal and epithelial Ki67 (P = 0.03 and 0.04, respectively). Epithelial pRb scores of 7 (range 0-7) were significantly associated with reduced disease-free survival (DFS) compared with scores of <7 (P = 0.0009). No relationship was found between cyclin D1 expression in either the epithelium or the stroma, and grade or DFS. CONCLUSIONS: The results suggest that alterations at the G(1)/S transition of the cell cycle play an important role in the progression of PTs.

Impact of the Adalimumab Patient Support Program's Care Coach Calls on Persistence and Adherence in Canada: An Observational Retrospective Cohort Study.

PURPOSE: Adalimumab (ADA) is a tumor necrosis factor-α inhibitor indicated for use in various immune-mediated inflammatory diseases. Patients receiving ADA in Canada are eligible to enroll in the AbbVie Care's Patient Support Program (PSP), which provides personalized services, including tailored interventions in the form of nurse-provided care coach calls (CCCs), with the goal of improving patients' experiences and outcomes. The primary objective of this study was to evaluate the impact of PSP services, including CCCs and patient characteristics, on persistence with and adherence to ADA for those patients enrolled in the PSP. A secondary objective was to estimate the effect of initial CCCs on treatment-initiation abandonment (ie, failure to initiate therapy after enrollment in the PSP). METHODS: An observational retrospective cohort study was conducted. A patient linkage algorithm based on probabilistic matching was developed to link the AbbVie Care PSP database to the QuintilesIMS longitudinal pharmacy transaction database. Patients who started ADA therapy between July 2010 and August 2014 were selected, and their prescriptions were evaluated for 12 months after the date of ADA start to calculate days until drug discontinuation, that is, the end of persistence, defined as >90 days without therapy. Cox proportional hazards modeling was used for estimating hazard ratios for the association between persistence and patient characteristics and each PSP service. Adherence, measured by medication possession ratio, was calculated, and multivariate logistic regression provided adjusted odds ratios for the relationship between being adherent (medication possession ratio ≥80%) and patient characteristics and each PSP service. Treatment-initiation abandonment among patients who received an initial CCC compared with those who did not was analyzed using the χ2 test. FINDINGS: Analysis of 10,857 linked patients yielded statistically significant differences in the hazard ratio of discontinuation and the likelihood of being adherent across multiple variables between patients who received CCCs in comparison to patients who did not. Patients receiving CCCs were found to have a 72% decreased risk for therapy discontinuation (hazard ratio = 0.282; P < 0.0001), and a greater likelihood of being adherent (odds ratio = 1.483; P < 0.0001), when compared with those patients who did not receive CCCs. The rate of treatment-initiation abandonment was significantly higher in patients who did not receive initial CCCs (P < 0.0001). IMPLICATIONS: Ongoing CCCs, provided by AbbVie Care PSP, were associated with greater patient persistence and adherence over the first 12 months of treatment, while initial CCCs were associated with a lower rate of treatment-initiation abandonment. Results may inform the planning of interventions aimed at improving treatment adherence and patient outcomes.

PROXIMO--a new docking algorithm to model protein complexes using data from radical probe mass spectrometry (RP-MS).

The design and implementation of a new algorithm, known as PROXIMO for protein oxidation interface modeller, is described to predict the structure of protein complexes using data generated in radical probe mass spectrometry (RP-MS) experiments. Photochemical radiolysis and discharge sources can be used to effect RP-MS in which hydroxyl radicals are formed directly from the bulk solvent on millisecond timescales and react with surface accessible residues in footprinting-like experiments. The algorithm utilizes a geometric surface fitting routine to predict likely structures for protein complexes. These structures are scored based on a correlation between the measured solvent accessibility of oxidizable residue side chains and oxidation shielding data obtained by RP-MS. The algorithm has been implemented to predict structures for the ribonuclease S-protein-peptide and calmodulin-melittin complexes using RP-MS data generated in this laboratory. The former is in close agreement with the high-resolution experimental structure available.

BRAF mutation, NRAS mutation, and the absence of an immune-related expressed gene profile predict poor outcome in patients with stage III melanoma.

Prediction of outcome for melanoma patients with surgically resected macroscopic nodal metastases is very imprecise. We performed a comprehensive clinico-pathologic assessment of fresh-frozen macroscopic nodal metastases and the preceding primary melanoma, somatic mutation profiling, and gene expression profiling to identify determinants of outcome in 79 melanoma patients. In addition to disease stage 4 years, 90% confidence interval): the presence of a nodular component in the primary melanoma (6.8, 0.6-76.0), and small cell size (11.1, 0.8-100.0) or low pigmentation (3.0, 0.8-100.0) in the nodal metastases. Absence of BRAF mutation (20.0, 1.0-1000.0) or NRAS mutation (16.7, 0.6-1000.0) were both favorable prognostic factors. A 46-gene expression signature with strong overrepresentation of immune response genes was predictive of better survival (10.9, 0.4-325.6); in the full cohort, median survival was >100 months in those with the signature, but 10 months in those without. This relationship was validated in two previously published independent stage III melanoma data sets. We conclude that the presence of BRAF mutation, NRAS mutation, and the absence of an immune-related expressed gene profile predict poor outcome in melanoma patients with macroscopic stage III disease.