Obesity underpins the development of numerous chronic diseases, such as type II diabetes mellitus. It is well established that obesity negatively alters immune cell frequencies and functions. Mucosal-associated invariant T (MAIT) cells are a population of innate T cells, which we have previously reported are dysregulated in obesity, with altered circulating and adipose tissue frequencies and a reduction in their IFN-g production, which is a critical effector function of MAIT cells in host defense. Hence, there is increased urgency to characterize the key molecular mechanisms that drive MAIT cell effector functions and to identify those which are impaired in the obesity setting. In this study, we found that MAIT cells significantly upregulate their rates of glycolysis upon activation in an mTORC1-dependent manner, and this is essential for MAIT cell IFN-g production. Furthermore, we show that mTORC1 activation is dependent on amino acid transport via SLC7A5. In obese patients, using RNA sequencing, Seahorse analysis, and a series of in vitro experiments, we demonstrate that MAIT cells isolated from obese adults display defective glycolytic metabolism, mTORC1 signaling, and SLC7A5 aa transport. Collectively, our data detail the intrinsic metabolic pathways controlling MAIT cell cytokine production and highlight mTORC1 as an important metabolic regulator that is impaired in obesity, leading to altered MAIT cell responses.

Oesophageal adenocarcinoma (OAC) is an aggressive malignancy with poor prognosis, and incidence is increasing rapidly in the Western world. Mucosal-associated invariant T (MAIT) cells recognize bacterial metabolites and kill infected cells, yet their role in OAC is unknown. We aimed to elucidate the role of MAIT cells during cancer development by characterizing the frequency, phenotype, and function of MAIT cells in human blood and tissues, from OAC and its pre-malignant inflammatory condition Barrett's oesophagus (BO). Blood and tissues were phenotyped by flow cytometry and conditioned media from explanted tissue was used to model the effects of the tumor microenvironment on MAIT cell function. Associations were assessed between MAIT cell frequency, circulating inflammatory markers, and clinical parameters to elucidate the role of MAIT cells in inflammation driven cancer. MAIT cells were decreased in BO and OAC blood compared to healthy controls, but were increased in oesophageal tissues, compared to BO-adjacent tissue, and remained detectable after neo-adjuvant treatment. MAIT cells in tumors expressed CD8, PD-1, and NKG2A but lower NKG2D than BO cohorts. MAIT cells produced less IFN-γ and TNF-α in the presence of tumor-conditioned media. OAC cell line viability was reduced upon exposure to expanded MAIT cells. Serum levels of chemokine IP-10 were inversely correlated with MAIT cell frequency in both tumors and blood. MAIT cells were higher in the tumors of node-negative patients, but were not significantly associated with other clinical parameters. This study demonstrates that OAC tumors are infiltrated by MAIT cells, a type of CD8 T cell featuring immune checkpoint expression and cytotoxic potential. These findings may have implications for immunotherapy and immune scoring approaches.

In response to an accumulation of unfolded proteins in the endoplasmic reticulum (ER) lumen, three ER transmembrane signaling proteins, inositol-requiring enzyme 1 (IRE1), PRKRlike ER kinase (PERK), and activating transcription factor 6␣ (ATF6␣), are activated. These proteins initiate a signaling and transcriptional network termed the unfolded protein response (UPR), which re-establishes cellular proteostasis. When this restoration fails, however, cells undergo apoptosis. To investigate cross-talk between these different UPR enzymes, here we developed a high-content live cell screening platform to image fluorescent UPR-reporter cell lines derived from human SH-SY5Y neuroblastoma cells in which different ER stress signaling proteins were silenced through lentivirus-delivered shRNA constructs. We observed that loss of ATF6 expression results in uncontrolled IRE1-reporter activity and increases X boxbinding protein 1 (XBP1) splicing. Transient increases in both IRE1 mRNA and IRE1 protein levels were observed in response to ER stress, suggesting that IRE1 up-regulation is a general feature of ER stress signaling and was further increased in cells lacking ATF6 expression. Moreover, overexpression of the transcriptionally active N-terminal domain of ATF6 reversed the increases in IRE1 levels. Furthermore, inhibition of IRE1 kinase activity or of downstream JNK activity prevented an increase in IRE1 levels during ER stress, suggesting that IRE1 transcription is regulated through a positive feed-forward loop. Collectively, our results indicate that from the moment of activation, IRE1 signaling during ER stress has an ATF6-dependent "off-switch." Figure 2. Employing high-content live cell imaging to interrogate cross-talk between the UPR-signaling branches. IRE1-, PERK-, or ATF6-reporter cells were transduced with shRNA against ATF6, IRE1, PERK, or scrambled control vector. 96 h after transduction, the cells were stained with Hoechst and PI and treated with 1 M Tg. Images were taken at 1-h intervals starting immediately after treatment for 48 h using high-content time-lapse live cell imaging. Left column: A, D, G, J, M, and P, schematic indicating reporter cell line and silencing construct used. Middle column: B and E, percentage of YFP-positive cells, or H, K, N, and R, mean YFP intensity over time in response to 1 M Tg or 0.1% DMSO in reporter cells transduced with silencing construct or scrambled control group was plotted. Error bars indicate S.E. of at least n ϭ 2 wells of a representative experiment. Right column: C and F, mean percentage of YFP-positive cells, or I, L, O, and Q, mean YFP intensity 24 h after treatment with 1 M Tg or 0.1% DMSO control. Error bars indicate S.E. of n ϭ 3 independent experiments. Student's t tests were performed comparing KD and scrambled groups. * indicates p Ͻ 0.05. a.u., arbitrary units. ATF6-dependent off-switch

Despite substantial diversity in study design, sample size, and parental eating disorder definition, overall, existing research suggests that the children of parents with eating disorders exhibit compromised development: a greater risk of perinatal complications; a tendency toward extremes of growth at birth; greater problems in feeding and eating behaviors and greater incidence of eating disorder symptoms; more psychological and socioemotional difficulties; and more negative qualities to parent-child interactions. Data on children's cognitive outcomes is thus far inconsistent. Given the relatively high incidence of eating disorder history in individuals of childbearing age, research into its potential effects on children is necessary. However, the methodological shortcomings and a limited evidence base caution in drawing conclusions. Nevertheless, mental health services should address the possible problems that these children face and offer tailored programs.

Objective We sought to identify predictors and moderators of failure to engage (i.e., pretreatment attrition) and dropout in both Internet-based and traditional face-to-face cognitive-behavioral therapy (CBT) for bulimia nervosa. We also sought to determine if Internet-based treatment reduced failure to engage and dropout. Method Participants (N = 191, 98% female) were randomized to Internet-based CBT (CBT4BN) or traditional face-to-face group CBT (CBTF2F). Sociodemographics, clinical history, eating disorder severity, comorbid psychopathology, health status and quality of life, personality and temperament, and treatment-related factors were investigated as predictors. Results Failure to engage was associated with lower perceived treatment credibility and expectancy (odds ratio [OR] = 0.91, 95% CI: 0.82, 0.97) and body mass index (BMI) (OR = 1.10; 95% CI: 1.03, 1.18). Dropout was predicted by not having a college degree (hazard ratio [HR] = 0.55; 95% CI: 0.37, 0.81), novelty-seeking (HR = 1.02; 95% CI: 1.01, 1.03), previous CBT experience (HR = 1.77; 95% CI: 1.16, 2.71), and randomization to the individual's nonpreferred treatment format (HR = 1.95, 95% CI: 1.28, 2.96). Discussion Those most at risk of failure to engage had a higher BMI and perceived treatment as less credible and less likely to succeed. Dropout was associated with less education, higher novelty-seeking, previous CBT experience, and a mismatch between preferred and assigned treatment. Contrary to expectations, Internet-based CBT did not reduce failure to engage or dropout.

The findings support dimensions of restraint, eating concern, weight concern, and shape concern in a clinical pediatric sample. This supports the factorial validity of the EDE, and the norms may assist clinicians to evaluate symptoms in females under 18 years.

Background:Perfectionism is a transdiagnostic risk factor across psychopathology. The Clinical Perfectionism Questionnaire (CPQ) was developed to assess change in order to provide clinical utility, but currently the psychometric properties of the CPQ with adolescents is unknown.Aims:To assess the factor structure and construct validity of the CPQ in female adolescents.Method:The CPQ was administered to 267 females aged 14–19 years of age. Confirmatory factor analysis (CFA) was used to examine the validity of the two-factor model and a second-order factor model. Pearson correlations were used to evaluate the relationships between the CPQ and a wide range of measures of perfectionism, psychopathology and personality traits.Results:The study demonstrated internal consistency, construct validity and incremental validity of the CPQ in a sample of female adolescents. The CFA in the present study confirmed the two-factor model of the CPQ with Factor 1 relating to perfectionistic strivings and Factor 2 representing perfectionistic concerns. The second-order two factor model indicated no deterioration in fit.Conclusions:The two-factor model of the CPQ fits with the theoretical definition of clinical perfectionism where the over-dependence of self-worth on achievement and concern over mistakes are key elements. The CPQ is suitable for use with female adolescents in future research that seeks to better understand the role of perfectionism in the range of mental illnesses that impact youth.

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