Sensing and guiding cell-state transitions by using genetically encoded endoribonuclease-mediated microRNA sensors.

Precisely sensing and guiding cell-state transitions via the conditional genetic activation of appropriate differentiation factors is challenging. Here we show that desired cell-state transitions can be guided via genetically encoded sensors, whereby endogenous cell-state-specific miRNAs regulate the translation of a constitutively transcribed endoribonuclease, which, in turn, controls the translation of a gene of interest. We used this approach to monitor several cell-state transitions, to enrich specific cell types and to automatically guide the multistep differentiation of human induced pluripotent stem cells towards a haematopoietic lineage via endothelial cells as an intermediate state. Such conditional activation of gene expression is durable and resistant to epigenetic silencing and could facilitate the monitoring of cell-state transitions in physiological and pathological conditions and eventually the 'rewiring' of cell-state transitions for applications in organoid-based disease modelling, cellular therapies and regenerative medicine.

MORC2 phosphorylation fine tunes its DNA compaction activity.

Variants in the poorly characterised oncoprotein, MORC2, a chromatin remodelling ATPase, lead to defects in epigenetic regulation and DNA damage response. The C-terminal domain (CTD) of MORC2, frequently phosphorylated in DNA damage, promotes cancer progression, but its role in chromatin remodelling remains unclear. Here, we report a molecular characterisation of full-length, phosphorylated MORC2, demonstrating its preference for binding open chromatin and functioning as a DNA sliding clamp. We identified a phosphate interacting motif within the CTD that dictates ATP hydrolysis rate and cooperative DNA binding. The DNA binding impacts several structural domains within the ATPase region. We provide the first visual proof that MORC2 induces chromatin remodelling through ATP hydrolysis-dependent DNA compaction, regulated by its phosphorylation state. These findings highlight phosphorylation of MORC2 CTD as a key modulator of chromatin remodelling, presenting it as a potential therapeutic target.

Causes of mortality in military working dog from traumatic injuries.

Introduction: This study aimed to identify the pathophysiologic causes of death following traumatic injuries in military working dogs (MWDs) and determine the risk factors associated with mortality in MWD following traumatic injuries. The results of this study will allow for better targeting of interventions to ameliorate these pathophysiologic causes of death and inform research priorities directed at the pathophysiology that leads to the death of MWDs. Methods: The final dataset for this study was compiled by using two previously established datasets. Based on review of available data and supplemental records (when available), MWDs in which a definitive cause of death could be determined were included in the study population. These MWDs were assigned a cause of death based on categories previously identified in studies evaluating service member casualties. A group of MWDs who survived their traumatic injury and had similar mechanisms of injury and types of injury to the deceased MWDs were included to allow for comparison and establishment of risk factors associated with MWD death. Variables collected included breed, age, sex, mechanism of injury, survival/non-survival, type of trauma, mechanism of injury, pathophysiology that led to death and pre-hospital care provided. Statistical analysis included Fishers exact test for categorical variables and univariable and multivariable logistic regression to identify factors associated with the MWD death. Results: A total of 84 MWDs (33 non-survivors and 51 survivors) were included in this study. Of the 33 MWDs that died, 27 (81.8%) were noted to be dead on arrival. The pathophysiologic causes of death were found to be hemorrhage (45.5% [n = 15]), head trauma (21.2% [n = 7]), catastrophic tissue destruction (15.2% [n = 5]), pneumothorax (9.1% [n = 3]) and one (3% [n = 1]) of each of the following: septic shock, asphyxiation and burns. Military working dogs that did not receive non-DVM care were 3.55 times more likely to die than those that did receive non-DVM care (95% CI 1.03-12.27). The majority of MWDs died of their injuries before reaching veterinary care. Discussion: To increase the survival of MWDs on the battlefield, further research should focus on developing new interventions and techniques to mitigate the effects of the pathophysiology noted to cause MWD death. Furthermore, given that care by a non-DVM was found to be associated with survival, the implementation of pre-hospital care and early resuscitation techniques should be a continued priority for those treating MWDs at both the point of injury and in the prehospital setting.

A Randomized Comparison of Postprandial Glucose Excursion Using Inhaled Insulin Versus Rapid-Acting Analog Insulin in Adults With Type 1 Diabetes Using Multiple Daily Injections of Insulin or Automated Insulin Delivery.

OBJECTIVE: To compare postprandial glucose excursions following a bolus with inhaled technosphere insulin (TI) or subcutaneous rapid-acting analog (RAA) insulin. RESEARCH DESIGN AND METHODS: A meal challenge was completed by 122 adults with type 1 diabetes who were using multiple daily injections (MDI), a nonautomated pump, or automated insulin delivery (AID) and who were randomized to bolus with their usual RAA insulin (n = 61) or TI (n = 61). RESULTS: The primary outcome, the treatment group difference in area under the curve for glucose >180 mg/dL over 2 h, was less with TI versus RAA (adjusted difference -12 mg/dL, 95% CI -22 to -2, P = 0.02). With TI, the glucose excursion was smaller (P = 0.01), peak glucose lower (P = 0.01), and time to peak glucose shorter (P = 0.006). Blood glucose <70 mg/dL occurred in one participant in each group. CONCLUSIONS: Postmeal glucose excursion was smaller with TI than with RAA insulin in a cohort that included both AID and MDI users.

Protease shaving of Mycobacterium tuberculosis facilitates vaccine antigen discovery and delivery of novel cargoes to the Mtb surface.

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), is the leading cause of infectious disease death and lacks a vaccine capable of protecting adults from pulmonary TB. Studies have shown that Mtb uses a variety of mechanisms to evade host immunity. Secreted Mtb proteins such as Type VII secretion system substrates have been characterized for their ability to modulate anti-Mtb immunity; however, studies of other pathogens such as Salmonella Typhi and Staphylococcus aureus have revealed that outer membrane proteins can also interact with the innate and adaptive immune system. The Mtb outer membrane proteome has received relatively less attention due to limited techniques available to interrogate this compartment. We filled this gap by deploying protease shaving and quantitative mass spectrometry to identify Mtb outer membrane proteins which serve as nodes in the Mtb-host interaction network. These analyses revealed several novel Mtb proteins on the Mtb surface largely derived from the PE/PPE class of Mtb proteins, including PPE18, a component of a leading Mtb vaccine candidate. We next exploited the localization of PPE18 to decorate the Mtb surface with heterologous proteins and deliver these surface-engineered Mtb to the phagosome. Together, these studies reveal potential novel targets for new Mtb vaccines as well as facilitate new approaches to study difficult to study cellular compartments during infection.

Recruitment strategies and consent rates in a national prospective colorectal cancer screening cohort: results from year 1 of the Voyage Study.

OBJECTIVE: To identify the optimal incentive protocol for maximising participation while managing study costs during the Voyage trial. DESIGN: Prospective cohort (Voyage trial) of colorectal cancer (CRC) incidence and mortality outcomes in individuals screened with multitarget stool DNA (mt-sDNA) served as the population. A subset was randomised to receive postage stamps as a pre-consent incentive, or as a post-consent incentive after completion of the consent and questionnaire. Descriptive statistics from year 1 are reported. RESULTS: During year 1 of the Voyage trial, a total of 600 258 individuals with mt-sDNA orders received at Exact Sciences Laboratories were randomly selected and invited to participate. Of those, 26 429 (4.4%) opted in, 14 365 of whom (54.3%) consented. The opt-in and consent samples were similar to the target population with respect to sex but differed by geographic residence and age (p<0.001). For the embedded incentive experiment, 2333 were randomised to the pre-incentive arm, while 2342 were randomised to the post-incentive arm. Overall consent rate in the incentive trial was 56.4% (60.9% for the pre-consent incentive arm (1421/2333) vs 52.0% for the post-consent incentive arm (1217/2342), p<0.001). Cost reduction was observed for the pre-consent incentive group, and higher response rates were seen among older versus younger individuals. CONCLUSIONS: Pre-consent incentive option was associated with a higher participation rate and lower costs and was used for the remainder of study recruitment. CRC incidence and mortality vary with age; thus, adjusting for differential participation by age and region will be important in analyses of Voyage data. TRIAL REGISTRATION NUMBER: NCT04124406.

Incidence of and risk factors for paediatric perioperative anaphylaxis in the USA.

BACKGROUND: Perioperative anaphylaxis is a serious and often life-threatening immediate hypersensitivity reaction. There are few published data on paediatric perioperative anaphylaxis (pPOA). We evaluated the incidence of and risk factors involved in the occurrence of pPOA within a large US national database. METHODS: Deidentified data from the US Nationwide Inpatient Sample from 2005 to 2014 were used to identify pPOA cases and to conduct a retrospective multivariate analysis of preselected independent variables. RESULTS: Among 3,601,180 surgeries and procedures in children aged 0-18 yr, 297 pPOA cases were identified for an incidence of one in 12,125 surgeries and procedures. Compared with controls, pPOA cases had an increased median length of stay (6 vs 2 days; P<0.001) and median hospital cost ($54 719 vs $5109; P<0.0001). The age groups between 6 and 12 yr (odds ratio [OR] 7.1; 95% confidence interval [CI] 3.9-12.9; P<0.001) and 13 and 17 yr (OR 8.5; 95% CI 4.7-15.2; P<0.001) were associated with increased odds of pPOA. Transplant (OR 46.3; 95% CI 20.8-102.9; P<0.001), cardiac (OR 16.4; 95% CI 7.5-35.9; P<0.001), and vascular (OR 15.2; 95% CI 7.5-30.7; P<0.001) procedures posed the highest risk for pPOA. Chronic pulmonary disease, coagulopathy, and fluid and electrolyte disorders were also associated with pPOA (OR 2.2; 95% CI 1.5-3.3; P<0.001). CONCLUSIONS: The incidence of pPOA was one in 12,125 cases. Risk factors included age, procedure type, and comorbidities.

Analyses of 1,236 genotyped primary ciliary dyskinesia individuals identify regional clusters of distinct DNA variants and significant genotype-phenotype correlations.

BACKGROUND: Primary ciliary dyskinesia (PCD) represents a group of rare hereditary disorders characterized by deficient ciliary airway clearance that can be associated with laterality defects. We aimed to describe the underlying gene defects, geographical differences in genotypes and their relationship to diagnostic findings and clinical phenotypes. METHODS: Genetic variants and clinical findings (age, sex, body mass index, laterality defects, FEV1) were collected from 19 countries using the ERN LUNG International PCD Registry. Genetic data were evaluated according to ACMG guidelines. We assessed regional distribution of implicated genes and genetic variants as well as genotype correlations with laterality defects and FEV1. RESULTS: 1236 individuals carried 908 distinct pathogenic DNA variants in 46 PCD genes. We found considerable variation in the distribution of PCD genotypes across countries due to the presence of distinct founder variants. The prevalence of PCD genotypes associated with pathognomonic ultrastructural defects (mean 72%; 47-100%) and laterality defects (mean 42%; 28-69%) varied widely among the countries. The prevalence of laterality defects was significantly lower in PCD individuals without pathognomonic ciliary ultrastructure defects (18%). The PCD cohort had a reduced median FEV1 z-score (-1.66). In the group of individuals with CCNO (-3.26), CCDC39 (-2.49), and CCDC40 (-2.96) variants, FEV1 z-scores were significantly lower, while the group of DNAH11 (-0.83) and ODAD1 (-0.85) variant individuals had significantly milder FEV1 z-score reductions compared to the whole PCD cohort. CONCLUSION: This unprecedented multinational dataset of DNA variants and information on their distribution across countries facilitates interpretation of genetic epidemiology of PCD and provides prediction of diagnostic and phenotypic features such as the course of lung function.

The Prevalence and Benefits of Self-Compassion Among Professional Caregivers.

OBJECTIVE: Self-compassion is a healthy way of responding to challenges that may help long-term care professional caregivers (ie, nursing assistants and personal care aides) cope with stress, but its use may vary in important ways. This study explored the relationships between self-compassion and caregiver demographic characteristics, anxiety and depressive symptoms, and job satisfaction in a large racially/ethnically diverse sample of professional caregivers. DESIGN: Cross-sectional self-report questionnaire. SETTING AND PARTICIPANTS: A total of 391 professional caregivers, including nursing assistants and personal care aides from 10 nursing homes and 3 assisted living communities in New York, California, and North Carolina. METHODS: Professional caregivers were invited to complete an online questionnaire regarding stress and coping. Self-compassion was measured using the Self-Compassion for Youth Scale; anxiety and depressive symptoms were assessed using standardized screeners; and job satisfaction was assessed via an item used in a national survey. Self-compassion scores were represented by total scores and individual subscale scores. Analysis of variance was used to examine differences in self-compassion scores based on demographic characteristics, and correlation coefficients were used to explore relationships between self-compassion and mental health symptoms and job satisfaction. RESULTS: Significant differences were found in self-compassion based on age, race/ethnicity, place of birth, and education. In general, older caregivers, caregivers with higher education, and caregivers born outside the United States had the highest self-compassion, whereas White caregivers had the lowest self-compassion. Self-compassion was negatively associated with anxiety and depressive symptoms and positively associated with job satisfaction. CONCLUSION AND IMPLICATIONS: Professional caregivers' use of self-compassion to cope with challenges may depend on characteristics and life experiences influenced by their sociocultural background. Given the link between self-compassion and lower mental health symptoms and higher job satisfaction, it may be helpful to design and implement interventions with these differences in mind.

Calcineurin inhibition rescues alloantigen-specific central memory T cell subsets that promote chronic GVHD.

Calcineurin inhibitors (CNIs) constitute the backbone of modern acute graft-versus-host disease (aGVHD) prophylaxis regimens but have limited efficacy in the prevention and treatment of chronic GVHD (cGVHD). We investigated the effect of CNIs on immune tolerance after stem cell transplantation with discovery-based single-cell gene expression and T cell receptor (TCR) assays of clonal immunity in tandem with traditional protein-based approaches and preclinical modeling. While cyclosporin and tacrolimus suppressed the clonal expansion of CD8+ T cells during GVHD, alloreactive CD4+ T cell clusters were preferentially expanded. Moreover, CNIs mediated reversible dose-dependent suppression of T cell activation and all stages of donor T cell exhaustion. Critically, CNIs promoted the expansion of both polyclonal and TCR-specific alloreactive central memory CD4+ T cells (TCM) with high self-renewal capacity that mediated cGVHD following drug withdrawal. In contrast to posttransplant cyclophosphamide (PT-Cy), CSA was ineffective in eliminating IL-17A-secreting alloreactive T cell clones that play an important role in the pathogenesis of cGVHD. Collectively, we have shown that, although CNIs attenuate aGVHD, they paradoxically rescue alloantigen-specific TCM, especially within the CD4+ compartment in lymphoid and GVHD target tissues, thus predisposing patients to cGVHD. These data provide further evidence to caution against CNI-based immune suppression without concurrent approaches that eliminate alloreactive T cell clones.

Discovery of KT-413, a Targeted Protein Degrader of IRAK4 and IMiD Substrates Targeting MYD88 Mutant Diffuse Large B-Cell Lymphoma.

Developing therapies for the activated B-cell like (ABC) subtype of diffuse large B-cell lymphomas (DLBCL) remains an area of unmet medical need. A subset of ABC DLBCL tumors is driven by activating mutations in myeloid differentiation primary response protein 88 (MYD88), which lead to constitutive activation of interleukin-1 receptor associated kinase 4 (IRAK4) and cellular proliferation. IRAK4 signaling is driven by its catalytic and scaffolding functions, necessitating complete removal of this protein and its escape mechanisms for complete therapeutic suppression. Herein, we describe the identification and characterization of a dual-functioning molecule, KT-413 and show it efficiently degrades IRAK4 and the transcription factors Ikaros and Aiolos. KT-413 achieves concurrent degradation of these proteins by functioning as both a heterobifunctional degrader and a molecular glue. Based on the demonstrated activity and safety of KT-413 in preclinical studies, a phase 1 clinical trial in B-cell lymphomas, including MYD88 mutant ABC DLBCL, is currently underway.

Determination and Identification of Antibiotic Residues in Fruits Using Liquid Chromatography-High-Resolution Mass Spectrometry (LC-HRMS).

Antibiotic residues may be present in fruit products from trees that were treated to combat bacterial diseases such as citrus greening or blight. A liquid chromatography-high-resolution mass spectrometry (LC-HRMS) method was developed for the simultaneous determination and identification of streptomycin, kasugamycin, penicillin, and oxytetracycline residues in fruit. Samples were extracted with acidic methanol and separation was optimized for a hydrophilic interaction LC column. A Q-Exactive HRMS instrument was used to obtain product ion spectra for analyte identification. Quantitation was performed with matrix-extracted calibration curves and internal standard correction. The method was tested on many different types of fruit. In general, fortified samples demonstrated acceptable recoveries (82-116%) and reproducibility (<15% RSD). Method detection limits for these analytes were well below the established US EPA tolerance levels. It was also possible to analyze the fruit extracts prepared using this method for additional chemical contaminants using LC-HRMS.

Microbiota dictate T cell clonal selection to augment graft-versus-host disease after stem cell transplantation.

Allogeneic T cell expansion is the primary determinant of graft-versus-host disease (GVHD), and current dogma dictates that this is driven by histocompatibility antigen disparities between donor and recipient. This paradigm represents a closed genetic system within which donor T cells interact with peptide-major histocompatibility complexes (MHCs), though clonal interrogation remains challenging due to the sparseness of the T cell repertoire. We developed a Bayesian model using donor and recipient T cell receptor (TCR) frequencies in murine stem cell transplant systems to define limited common expansion of T cell clones across genetically identical donor-recipient pairs. A subset of donor CD4+ T cell clonotypes differentially expanded in identical recipients and were microbiota dependent. Microbiota-specific T cells augmented GVHD lethality and could target microbial antigens presented by gastrointestinal epithelium during an alloreactive response. The microbiota serves as a source of cognate antigens that contribute to clonotypic T cell expansion and the induction of GVHD independent of donor-recipient genetics.

Regular Physician Access and Obesity Status Among Underserved Asian and Pacific Islander American Immigrants in Los Angeles.

According to prior research, Asian and Pacific Islander American (APIA) immigrants often refrain from seeking health care unless necessitated by medical conditions. Utilizing data from health screenings conducted in APIA immigrant enclaves in Los Angeles, we hypothesize that poorer obesity status would predict higher rates of regular physician access. Analyses involved objectively measured percent body fat (%BF) and survey responses collected between 2011 and 2019. We assessed the association between obesity status and regular physician access, adjusting for insurance status, demographic, and socioeconomic factors. The study population (n = 4102) primarily consisted low-income, low English proficiency APIAs. Participants with a regular physician were significantly more likely to be obese compared to participants without (adjusted odds ratio [aOR] = 1.28, 95% confidence interval [CI] = [1.03, 1.58], P = .02). This association may suggest that care was sought reactively rather than proactively within this community. Interventions with emphasis on cultural competency and language services may encourage preventative care utilization among this understudied community.

Suv39h-catalyzed H3K9me3 is critical for euchromatic genome organization and the maintenance of gene transcription.

H3K9me3-dependent heterochromatin is critical for the silencing of repeat-rich pericentromeric regions and also has key roles in repressing lineage-inappropriate protein-coding genes in differentiation and development. Here, we investigate the molecular consequences of heterochromatin loss in cells deficient in both SUV39H1 and SUV39H2 (Suv39DKO), the major mammalian histone methyltransferase enzymes that catalyze heterochromatic H3K9me3 deposition. We reveal a paradoxical repression of protein-coding genes in Suv39DKO cells, with these differentially expressed genes principally in euchromatic (Tn5-accessible, H3K4me3- and H3K27ac-marked) rather than heterochromatic (H3K9me3-marked) or polycomb (H3K27me3-marked) regions. Examination of the three-dimensional (3D) nucleome reveals that transcriptomic dysregulation occurs in euchromatic regions close to the nuclear periphery in 3D space. Moreover, this transcriptomic dysregulation is highly correlated with altered 3D genome organization in Suv39DKO cells. Together, our results suggest that the nuclear lamina-tethering of Suv39-dependent H3K9me3 domains provides an essential scaffold to support euchromatic genome organization and the maintenance of gene transcription for healthy cellular function.

Shortening treatment duration for uncomplicated community acquired pneumonia to align with best practice guidelines in a large academic paediatric emergency department.

Recommendations for antibiotic therapy for community acquired pneumonia recently changed from 10-day to 5-day duration. This quality improvement project aimed to change the practice of providers in an urban, free-standing children's hospital paediatric emergency department in the United States to match the updated recommendations. Improvement interventions included educational outreach, data sharing, on-site reminders, and audit-and-feedback. The project included analysis of ED return visits to monitor possible treatment failure. Interventions successfully increased 5-day antibiotic prescription rate from 3% to 85% within 12 months.

A US-Based Multicenter Retrospective Report of Perioperative Anaphylaxis, 2010-2021.

BACKGROUND: US-based perioperative anaphylaxis (POA) studies are limited to single-center experiences. A recent report found that a serum acute tryptase (sAT) >9.8 ng/mL or mast cell activation (MCA) can predict POA causal agent identification. Urinary mast cell mediator metabolites (uMC) have not been studied in POA. OBJECTIVE: To analyze the epidemiologic data of POA, to determine if sAT or MCA can predict suspected causal agent identification, and to evaluate uMC utility in POA. METHODS: This study is a retrospective multicenter review of POA cases that were subcategorized by suspected causal agent identification status. sAT, MCA (defined as sAT >2 + 1.2 × serum baseline tryptase), and uMC (N-methylhistamine [N-MH], 11ß-prostaglandin-F2α [11ß-PGF2α], leukotriene E4 [LTE4]) were recorded. RESULTS: Of 100 patients (mean age 52 [standard deviation 17] years, 94% adult, 50% female, 90% White, and 2% Hispanic) with POA, 73% had an sAT available, 41% had MCA, 16% had uMC available, and 50% had an identifiable suspected cause. POA cases with an identifiable suspected cause had a positive MCA status (100% vs 78%; P = .01) compared with POA with an unidentifiable cause. An elevated median sAT did not predict causal agent identification. Positive uMC were not associated with suspected causal agent identification during POA. Patients with positive uMC had a higher median sAT (30 vs 6.45 ng/mL; P = .001) and MCA status (96% vs 12%; P = .001) compared with negative uMC patients. Patients with POA had an elevated acute/baseline uMC ratios: 11ß-PGF2α ratio > 1.6, N-MH ratio >1.7, and LTE4 ratio >1.8. CONCLUSIONS: The presence of MCA in POA is associated with suspected causal agent identification. Positive uMC possibly correlate with a higher sAT level and MCA status but require further study. The authors suggest applying an acute/baseline uMC ratio (11ß-PGF2α ratio >1.6, N-MH ratio >1.7, and LTE4 ratio >1.87) in patients with POA for MCA when a tryptase level is inconclusive during POA evaluations.

TIM-3+ CD8 T cells with a terminally exhausted phenotype retain functional capacity in hematological malignancies.

Chronic antigen stimulation is thought to generate dysfunctional CD8 T cells. Here, we identify a CD8 T cell subset in the bone marrow tumor microenvironment that, despite an apparent terminally exhausted phenotype (TPHEX), expressed granzymes, perforin, and IFN-γ. Concurrent gene expression and DNA accessibility revealed that genes encoding these functional proteins correlated with BATF expression and motif accessibility. IFN-γ+ TPHEX effectively killed myeloma with comparable efficacy to transitory effectors, and disease progression correlated with numerical deficits in IFN-γ+ TPHEX. We also observed IFN-γ+ TPHEX within CD19-targeted chimeric antigen receptor T cells, which killed CD19+ leukemia cells. An IFN-γ+ TPHEX gene signature was recapitulated in TEX cells from human cancers, including myeloma and lymphoma. Here, we characterize a TEX subset in hematological malignancies that paradoxically retains function and is distinct from dysfunctional TEX found in chronic viral infections. Thus, IFN-γ+ TPHEX represent a potential target for immunotherapy of blood cancers.