Discovery of Novel Oral Protein Synthesis Inhibitors of Mycobacterium tuberculosis That Target Leucyl-tRNA Synthetase

The recent development and spread of extensively drug-resistant and totally drug-resistant resistant (TDR) strains of Mycobacterium tuberculosis highlight the need for new antitubercular drugs. Protein synthesis inhibitors have played an important role in the treatment of tuberculosis (TB) starting with the inclusion of streptomycin in the first combination therapies. Although parenteral aminoglycosides are a key component of therapy for multidrug-resistant TB, the oxazolidinone linezolid is the only orally available protein synthesis inhibitor that is effective against TB. Here, we show that small-molecule inhibitors of aminoacyl-tRNA synthetases (AARSs), which are known to be excellent antibacterial protein synthesis targets, are orally bioavailable and effective against M. tuberculosis in TB mouse infection models. We applied the oxaborole tRNA-trapping (OBORT) mechanism, which was first developed to target fungal cytoplasmic leucyl-tRNA synthetase (LeuRS), to M. tuberculosis LeuRS. X-ray crystallography was used to guide the design of LeuRS inhibitors that have good biochemical potency and excellent whole-cell activity against M. tuberculosis. Importantly, their good oral bioavailability translates into in vivo efficacy in both the acute and chronic mouse models of TB with potency comparable to that of the frontline drug isoniazid

31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

Race Differences in Parental Influences on Child Achievement Multiple Pathways to Success

Using data from a national multiethnic, longitudinal study of children, this study examined the process of how parents’ educational attainment is related to children’s achievement through the beliefs and behaviors of parents and how this influence varies by race/ethnicity. Measures of socioeconomic status, parental expectations for educational success, reading, school involvement, and warmth were collected through home interviews. Achievement measures were collected in kindergarten and third grade. Using structural equation modeling techniques, we found parents’ educational attainment to be an important predictor of children’s achievement as well as the change in their achievement across time. Parental beliefs and behaviors were important indirect pathways of this influence, especially for European American families, but varied in important ways by race/ethnicity. Parents’ educational attainment is a powerful predictor of what parents provide in the home environment, and researchers and policymakers who want to understand children’s achievement need to examine the important role that education may play in child development

Increases in Maternal Education and Young Children’s Language Skills

Maternal education is a strong correlate of children’s language, cognitive, and academic development. In most prior research, mothers’ education has been treated as a fixed characteristic, yet many mothers, particularly economically and educationally disadvantaged mothers, attend school after the birth of their children. In the present study, we use longitudinal data from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development to consider whether increases in maternal education are associated with concurrent improvements in children’s school readiness, language skills, and the quality of home environments at age 3. Increases in mothers’ education are linked to young children’s expressive and receptive language skills but only among mothers with initially low levels of education. Increases in education are also associated with improvements in some aspects of children’s home environments, particularly mothers’ responsiveness and the provision of learning materials. Mediation analyses provide some evidence that improvements in children’s language associated with increased maternal education are due in part to changes in the quality of home environments

Allosteric modulation of M1 muscarinic acetylcholine receptor internalization and subcellular trafficking

Background: The effects of allosteric modulators on G protein-coupled receptor trafficking are largely unknown. Results: The allosteric ligand BQCA modulates M1 mAChR arrestin recruitment and receptor trafficking. Conclusion: M1 mAChR trafficking is arrestin- and G protein-dependent and modulated by BQCA. Significance: The impact of allosteric modulators on receptor trafficking needs to be assessed when considering this family of ligands as potential chronic therapies. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc. Published in the U.S.A