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This note studies the relationship between the gender composition of a student’s peers and two of their non-cognitive factors: sense of belonging and self-worth. Using data from Add Health and expl...

Background Treatment of chronic hepatitis C virus infection with direct acting antiviral therapy results in viral elimination in over 90% of cases. The duration of treatment required to achieve cure differs between individuals and relapse can occur. We asked whether cellular and transcriptional profiling of peripheral blood collected during treatment could identify biomarkers predictive of treatment outcome. Methods We analyzed peripheral blood collected during treatment of genotype 1 HCV with 24 weeks of sofosbuvir and weight-based or low dose ribavirin in a trial in which 29% of patients relapsed. Changes in host immunity during treatment were assessed by flow cytometry and whole blood gene expression profiling. Differences in expression of immune-relevant transcripts based on treatment outcome were analyzed using the Nanostring Human Immunology V2 panel. Results Multiple cellular populations changed during treatment, but pre-treatment neutrophil counts were lower and natural post-treatment killer cell counts were higher in patients who relapsed. Pre-treatment expression of genes associated with interferon-signaling, T-cell dysfunction, and T-cell co-stimulation differed by treatment outcome. We identified a pre- and post-treatment gene expression signature with high predictive capacity for distinguishing treatment outcome, but neither signature was sufficiently robust to suggest viability for clinical use. Conclusions Patients who relapse after hepatitis C virus therapy differ immunologically from non-relapsers based on expression of transcripts related to interferon signaling and T-cell dysfunction, as well as by peripheral neutrophil and NK-cell concentrations. These data provide insight into the host immunologic basis of relapse after DAA therapy for HCV and suggests mechanisms which may be relevant for understanding outcomes with currently approved regimens.

Treatment of chronic hepatitis C virus (HCV) infection with direct acting antivirals (DAAs) results in a sustained virologic response (SVR) in most patients. While highly efficacious, ~3–5% of patients do not achieve SVR despite having virus that appears susceptible. It is unclear whether host factors contribute to treatment failures, although innate and adaptive immunity may play a role. Previous studies showed that after DAA treatment, the composition of intrahepatic immune cells does not normalize relative to healthy volunteers, even in cases where SVR is achieved. We used paired pre- and post-treatment liver biopsies from 13 patients treated with sofosbuvir and ribavirin, 4 of whom relapsed, to analyze intracellular immune changes during DAA treatment and explore correlations with inflammation and treatment outcome. We performed single marker immunohistochemistry followed by electronic image capture, manual annotation of parenchymal and non-parenchymal regions, and quantitative image analysis. The predominant cellular change during treatment was a decrease in CD8+ cellular density in both parenchymal and non-parenchymal regions. CD68+ Kupffer cell density correlated with hepatic inflammation (AST, ALT) pre-treatment, but did not change during treatment. CD4+ cellular density decreased in non-parenchymal regions and, intriguingly, was lower pre-treatment in subjects who eventually relapsed. Other cellular markers (CD56, CD20), as well as markers of apoptosis (TIA-1) and activated stellate cells, did not change significantly during treatment or differ by treatment outcome. CONCLUSION: The predominant intrahepatic cellular change during DAA treatment of chronic HCV infection is a reduction in CD8+ cellular density, but this did not correlate with treatment outcome.

To identify immunologic correlates of hepatitis C virus (HCV) relapse after direct-acting antiviral (DAA) therapy, we quantified select immune transcripts in whole blood from noncirrhotic HCV subjects treated with 4–6 weeks of DAAs. We identified specific markers of natural killer-cell and CD8+ T-cell function (GZMB, PRF1, NKp46) with higher expression in subjects who relapsed. These findings suggest a role for host immunity in HCV eradication with ultrashort DAA therapy. We quantified whole blood immune transcripts in noncirrhotic HCV subjects treated with shortcourse antiviral therapy. Markers of natural killer-cell and CD8+ T-cell function had higher expression in virologic relapsers, suggesting a role for host immunity in HCV eradication.

Background and aims Most patients with cirrhosis induced by chronic HBV infection experience fibrosis regression after long-term antiviral treatment, while some remain cirrhotic. Fibrosis regression is associated with lower odds of developing hepatic decompensation and hepatocellular carcinoma, but mechanisms impacting differential fibrosis regression between individuals are unclear. We asked whether soluble molecules, including serum microRNAs, could serve as biomarkers of fibrosis regression. Methods We analysed cryopreserved sera from clinical trials in which cirrhotic HBV-infected patients (baseline Ishak fibrosis score of 5-6) received 240 weeks of nucleotide analogue treatment. Liver biopsies at week 240 in these trials showed 71/96 patients (74%) had fibrosis regression (Ishak ≤ 4) while 25/96 (26%) remained cirrhotic (Ishak 5-6). We quantified inflammatory markers (CXCL10, soluble CD163) and miRNAs (n = 179) from serum at baseline, week 48 and week 240 of treatment in a sub-cohort of patients with (n = 14) or without (n = 14) fibrosis regression. Results CXCL10, sCD163 and miRNAs previously associated with HBV replication and inflammation decreased during treatment but did not differ based on fibrosis regression. Two miRNAs (miR-421 and miR-454-3p) had lower baseline expression in patients with subsequent fibrosis regression. In all, 27 miRNAs differed at week 240 and had higher expression in patients with fibrosis regression (eg miR-199a-3p, miR-423-3p, miR-142-3p, miR-let-7d-5p). Several miRNAs (miR-141-3p, let-7d-5p) that correlated with regression have previously been implicated in the pathophysiology of non-alcoholic steatohepatitis. Conclusions In cirrhotic patients with chronic HBV infection treated with antiviral therapy, serum miRNAs have differential expression based on fibrosis regression, suggesting potential utility as biomarkers.

Cryptococcus neoformans is a facultative intracellular pathogen responsible for the most common cause of fungal meningioencephalitis, occurring primarily in immunocompromised individuals. Antiphagocytic protein 1 (App1) is a virulence factor produced by C. neoformans that inhibits phagocytosis of the yeast by host macrophages. Treatment of cryptococcosis includes amphotericin B, fluconazole, and flucytosine. Virulence factors have been shown to affect the susceptibility of the pathogen to antifungal drugs. In this study, we aimed to examine the relationship between App1 and antifungal drugs. We found that short-term exposure to amphotericin B downregulates APP1 expression while exposure to fluconazole upregulates APP1. In addition, App1 was found to increase the susceptibility of the yeast to amphotericin B and fluconazole. This study provides evidence of an intricate relationship between App1 and antifungal drugs.

IMPACT: We hope to provide a more nuanced understanding of the type-III IFN system, thereby exploring its therapeutic potential in the realm of infectious diseases. OBJECTIVES/GOALS: The role of IFNLR1 receptor dynamics and plasticity in regulating the type-III IFN response is largely unknown. As a specific, powerful component of innate immunity, understanding how the type-III IFN system is regulated could lead to the development of novel therapeutic targets and strategies to face a multitude of viral illnesses. METHODS/STUDY POPULATION: To facilitate our investigation, we will generate doxycycline-inducible FLAG-tagged IFNLR1-expression plasmids representing all known transcriptional variants. These plasmids will allow us to: 1) Evaluate the effect of IFNLR1 surface abundance on the type-III IFN transcriptional profile and 2) Assess the extent of IFNLR1-FLAG co-localization with several notable intracellular structures using immunofluorescence, before and after stimulation with IFNL3. RESULTS/ANTICIPATED RESULTS: We have successfully generated three IFNLR1-FLAG transcriptional variants and confirmed inducible-expression and function in vitro. We are currently assessing the role of surface abundance, internalization, differential isoform expression, and trafficking. DISCUSSION/SIGNIFICANCE OF FINDINGS: By completing this study, we hope to provide a more nuanced understanding of the type-III IFN system, thereby exploring its therapeutic potential in the realm of infectious diseases.

Treatment of chronic hepatitis C virus (HCV) infection with direct‐acting antivirals results in a rapid decline in viral load and markers of hepatic inflammation, including serum chemokine (C‐X‐C motif) ligand 10 (CXCL10) concentration, which is followed in most cases by a sustained virologic response. Whether parallel changes of significance occur in the cellular composition of peripheral blood is relatively unknown. We hypothesized that longitudinal characterization of peripheral blood during treatment would provide insight into cellular migration and immune activation, which would have implications for understanding host immunity both before and after HCV treatment and may relate to HCV clearance. We analyzed longitudinal peripheral innate and adaptive immune cell populations by flow cytometry from 95 subjects enrolled in two direct‐acting antiviral clinical trials and examined chemokine receptor expression on T lymphocytes in 43 patients. Within 1‐2 weeks of initiating treatment, significant increases were observed in the concentration of peripheral cluster of differentiation 4–positive (CD4+) and CD8+ T lymphocytes but not monocyte or natural killer cells. In tandem with these changes, the percent of both CD4+ and CD8+ T lymphocytes with an activated phenotype (human leukocyte antigen [HLA] DR+ and CD38+) decreased, and T‐lymphocyte surface expression of chemokine (C‐X‐C motif) receptor 3, the chemokine receptor for CXCL10, increased. Conclusion: Rapid changes in peripheral cellular populations occur during direct‐acting antiviral treatment of HCV infection, which could potentially relate to hepatic efflux of tissue lymphocytes due to altered inflammation and chemokine receptor signaling, providing critical insight into the relationship between host immunity and viral clearance during HCV infection. (Hepatology Communications 2017;1:586–594)

Objectives The opioid epidemic has resulted in rising rates of hepatitis C virus (HCV) infection in women of childbearing age. With this changing epidemiology in mind, the Infectious Diseases Society of America/American Association for the Study of Liver Diseases guidelines were updated in 2018 to recommend screening all pregnant women for HCV infection, irrespective of risk factors. Because HCV infection can affect maternal-fetal health and result in vertical transmission, presentation for pregnancy-related medical care represents an opportunity to diagnose and manage HCV infection, as well as prepare for treatment postpartum. Methods We performed a retrospective chart review spanning 2007-2016 to examine the epidemiology of HCV infection and opioid use disorder in a southern academic obstetrical clinic and to explore the impact of new screening guidelines if implemented. Composite data from the electronic health record and individual chart review were used to determine rates of HCV infection and opioid use disorder in obstetrics, explore patient demographics, and examine perinatal outcomes. Results Rates of both opioid use disorder and chronic HCV infection increased significantly during the 10-year period of analysis. Patients diagnosed as having chronic HCV infection were primarily white (95%) and there was no observed impact of HCV on perinatal outcomes. HCV testing in pregnancy, even when patients had documented opioid use disorder, was infrequent (0.7% of all pregnancies). Documented follow-up for HCV postpartum for both mothers and infants was incomplete, with only one-third of identified HCV-exposed infants referred and only 9% receiving HCV testing at our institution. Conclusions HCV prevalence increased between 2007 and 2016, but screening and treatment of HCV in this southern obstetrical cohort was infrequent. The implementation of universal screening in pregnancy will likely identify additional cases, and an improved cascade of care will be necessary to address the HCV epidemic.

Quorum sensing is a form of communication observed in different species of microbes. Numerous studies have shown the ability of bacteria and fungi to carry out quorum sensing by releasing specific molecules to enable communication in a large population. Quorum sensing has been shown to influence growth, morphology, and other factors pertaining to virulence in pathogenic microbes. In this review, we address three important fungal species and explain how each fungus has a unique and dynamic way of communicating. Candida albicans is an opportunistic pathogen, or one that is part of the normal microbiota that can become pathogenic and cause several diseases. Here, we address two quorum sensing molecules (QSMs) identified by investigators. These chemicals are tyrosol and farnesol, which act together to control cellular growth, morphology and biofilm production. Another opportunistic fungal pathogen, Cryptococcus neoformans, has been shown to display quorum sensing activity by using pantothenic acid as well as a peptide called quorum sensing-like peptide 1. These molecules have both been shown to control growth rates of C. neoformans. Saccharomyces cerevisiae is another dimorphic fungus that uses QSMs, although it is nonpathogenic. Using two aromatic alcohols, phenylethanol and tryptophol, S. cerevisiae can alter pseudohyphal growth in diploid cells as well as invasive growth in haploid cells. By understanding more about the ways these organisms communicate, we present the potential for new and better targets for the treatment of fungal infections.