Publications

MicroRNAs (miRNAs) exert powerful effects on immunity through coordinate regulation of multiple target genes in a wide variety of cells. Type 2 innate lymphoid cells (ILC2s) are tissue sentinel mediators of allergic inflammation. We established the physiological requirements for miRNAs in ILC2 homeostasis and immune function and compared the global miRNA repertoire of resting and activated ILC2s and T helper type 2 (T2) cells. After exposure to the natural allergen papain, mice selectively lacking the miR-17∼92 cluster in ILC2s displayed reduced lung inflammation. Moreover, miR-17∼92-deficient ILC2s exhibited defective growth and cytokine expression in response to IL-33 and thymic stromal lymphopoietin in vitro. The miR-17∼92 cluster member miR-19a promoted IL-13 and IL-5 production and inhibited expression of several targets, including SOCS1 and A20, signaling inhibitors that limit IL-13 and IL-5 production. These findings establish miRNAs as important regulators of ILC2 biology, reveal overlapping but nonidentical miRNA-regulated gene expression networks in ILC2s and T2 cells, and reinforce the therapeutic potential of targeting miR-19 to alleviate pathogenic allergic responses.

Extended-release naltrexone (XRNTX) is an effective treatment for alcohol use disorder (AUD). We sought to evaluate the feasibility, acceptability, and preliminary effectiveness and cost-effectiveness of XRNTX delivered as a stand-alone service to persons with severe AUD who are high utilizers of multiple urgent and emergency medical services (HUMS). Of 15 HUMS persons with severe AUD selected based on chart review, 11 agreed to participate. Participants received a mean of 4.5 injections (range 2-7). Modest benefits from XRNTX were observed in terms of patients' Urge-to-Drink Score and the costs of emergency medical services utilized. Though limited by a small sample size, costs including client utilization and study related expenses during the post-enrollment period were less than client utilization costs in the pre-enrollment period. We also observed non-significant improvements in the number of drinking days, but no change in quality of life as measured by the EQ-5D. Eighty-eight percent of participants perceived XRNTX as helping with their drinking. Findings need to be replicated in a larger study, however if replicated, the cost savings could be substantial.

BACKGROUND

Epistasis and gene-environment interactions are known to contribute significantly to variation of complex phenotypes in model organisms. However, their identification in human association studies remains challenging for myriad reasons. In the case of epistatic interactions, the large number of potential interacting sets of genes presents computational, multiple hypothesis correction, and other statistical power issues. In the case of gene-environment interactions, the lack of consistently measured environmental covariates in most disease studies precludes searching for interactions and creates difficulties for replicating studies.

RESULTS

In this work, we develop a new statistical approach to address these issues that leverages genetic ancestry, defined as the proportion of ancestry derived from each ancestral population (e.g., the fraction of European/African ancestry in African Americans), in admixed populations. We applied our method to gene expression and methylation data from African American and Latino admixed individuals, respectively, identifying nine interactions that were significant at P<5×10-8. We show that two of the interactions in methylation data replicate, and the remaining six are significantly enriched for low P-values (P<1.8×10-6).

CONCLUSION

We show that genetic ancestry can be a useful proxy for unknown and unmeasured covariates in the search for interaction effects. These results have important implications for our understanding of the genetic architecture of complex traits.