A muscarinic receptor antagonist reverses multiple indices of diabetic peripheral neuropathy: preclinical and clinical studies using oxybutynin.

Preclinical studies indicate that diverse muscarinic receptor antagonists, acting via the M1 sub-type, promote neuritogenesis from sensory neurons in vitro and prevent and/or reverse both structural and functional indices of neuropathy in rodent models of diabetes. We sought to translate this as a potential therapeutic approach against structural and functional indices of diabetic neuropathy using oxybutynin, a muscarinic antagonist approved for clinical use against overactive bladder. Studies were performed using sensory neurons maintained in vitro, rodent models of type 1 or type 2 diabetes and human subjects with type 2 diabetes and confirmed neuropathy. Oxybutynin promoted significant neurite outgrowth in sensory neuron cultures derived from adult normal rats and STZ-diabetic mice, with maximal efficacy in the 1-100 nmol/l range. This was accompanied by a significantly enhanced mitochondrial energetic profile as reflected by increased basal and maximal respiration and spare respiratory capacity. Systemic (3-10 mg/kg/day s.c.) and topical (3% gel daily) oxybutynin reversed paw heat hypoalgesia in the STZ and db/db mouse models of diabetes and reversed paw tactile allodynia in STZ-diabetic rats. Loss of nerve profiles in the skin and cornea of db/db mice was also prevented by daily topical delivery of 3% oxybutynin for 8 weeks. A randomized, double-blind, placebo-controlled interventional trial was performed in subjects with type 2 diabetes and established peripheral neuropathy. Subjects received daily topical treatment with 3% oxybutynin gel or placebo for 6 months. The a priori designated primary endpoint, significant change in intra-epidermal nerve fibre density (IENFD) in skin biopsies taken before and after 20 weeks of treatments, was met by oxybutynin but not placebo. Secondary endpoints showing significant improvement with oxybutynin treatment included scores on clinical neuropathy, pain and quality of life scales. This proof-of-concept study indicates that muscarinic antagonists suitable for long-term use may offer a novel therapeutic opportunity for treatment of diabetic neuropathy. Trial registry number: NCT03050827.

In-Hospital Drug Use Affects a Broad Patient Population and the Health Care System.

INTRODUCTION: Patients who suffer from addiction sometimes take illicit substances while in the hospital (in-hospital drug use [IHDU]), which can lead to unnecessary work-up and preventable treatments when symptoms develop. The purpose of this study was to define the frequency and scope of this problem, who it affects, and its impact on the medical system. METHODS: We reviewed all incident reports from our large, urban level 1 trauma center that involved a patient being found with illicit substances in the hospital between January 2020 and January 2023. Reports were included if patients were witnessed taking the illicit substance or if they admitted to taking one in the hospital. Individual medical charts were then reviewed to determine the details of the incident and the response of the medical team. RESULTS: Thirty-one incidents meeting the inclusion criteria were found. Of the patients involved, 74.2% were male and ranged in age from 21 to 82 years old. The admitting services included internal or family medicine (48.4%), trauma (32.3%), surgical intensive care unit (ICU) (6.5%), medical ICU (6.5%), obstetrics and gynecology (3.2%), and plastic surgery (3.2%). Interventions ranged from no intervention to transfer to the ICU and intubation. 29.0% had visitors immediately prior to the incident, which may be how the substances were obtained. 16.1% left against medical advice after having their drugs confiscated. CONCLUSIONS: Our findings suggest that a broad range of patients are at risk for IHDU, and that IHDU can lead to medical complications, additional medical expense, or patients at risk of incomplete care due to leaving against medical advice. Future work is necessary to understand patient outcomes and financial implications of IHDU, as well as to develop tools to identify those patients most at risk.

And Miles to Go Before We Sleep: EAST Diversity and Inclusivity Progress and Remaining Challenges.

OBJECTIVE: The aim of this study was to examine the diversity, equity, and inclusion landscape in academic trauma surgery and the EAST organization. SUMMARY BACKGROUND DATA: In 2019, the Eastern Association for the Surgery of Trauma (EAST) surveyed its members on equity and inclusion in the #EAST4ALL survey and assessed leadership representation. We hypothesized that women and surgeons of color (SOC) are underrepresented as EAST members and leaders. METHODS: Survey responses were analyzed post-hoc for representation of females and SOC in academic appointments and leadership, EAST committees, and the EAST board, and compared to the overall respondent cohort. EAST membership and board demographics were compared to demographic data from the Association of American Medical Colleges. RESULTS: Of 306 respondents, 37.4% identified as female and 23.5% as SOC. There were no significant differences in female and SOC representation in academic appointments and EAST committees compared to their male and white counterparts. In academic leadership, females were underrepresented ( P < 0.0001), whereas SOC were not ( P = 0.08). Both females and SOC were underrepresented in EAST board membership ( P = 0.002 and P = 0.043, respectively). Of EAST's 33 presidents, 3 have been white women (9%), 2 have been Black, non-African American men (6%), and 28 (85%) have been white men. When compared to 2017 AAMC data, women are well-represented in EAST's 2020 membership ( P < 0.0001) and proportionally represented on EAST's 2019-2020 board ( P > 0.05). CONCLUSIONS: The #EAST4ALL survey suggests that women and SOC may be underrepresented as leaders in academic trauma surgery. However, lack of high-quality demographic data makes evaluating representation of structurally marginalized groups challenging. National trauma organizations should elicit data from their members to re-assess and promote the diversity landscape in trauma surgery.

Post-traumatic Liver Pseudoaneurysms: Rare but Serious Sequela.

INTRODUCTION: The liver is the most commonly injured organ after blunt abdominal trauma. Nonoperative management is the standard of care in stable individuals. Liver injuries, particularly high-grade injuries, can develop pseudoaneurysms (PSAs), which can rupture and cause life-threatening bleeding, even after hospital discharge. There is no consensus on whether patients should receive predischarge contrast computed tomography (CT) screening, or at what time interval after injury, nor which patients are at the highest risk for PSA. The purpose of this study was to identify the rates of PSA in our population and potential risk factors for their formation. METHODS: The trauma registry at our Level 1 urban trauma center was queried for patients admitted with liver injuries between 2015 and 2021. Demographic information was collected from the registry. Individual charts were then reviewed for timing of CT scans, CT findings, interventions, and complications. Liver injury grade was assessed using radiology reports or operative findings. The frequency of PSAs was then analyzed using descriptive statistics using Microsoft Excel and SPSS for odds ratio. RESULTS: A total of 172 patients were admitted with liver injuries during the study period. 130 patients received a CT scan diagnosing liver injury, 42 were diagnosed with liver injury intraoperatively. Of the 130 patients (59.9%) which received follow-up CT scans, six (6.5%) developed PSA, four of which being from penetrating injuries (odds ratio, 6.95). CONCLUSIONS: This study demonstrated a low incidence of PSA consistent with the known literature. We found the majority of the PSA developed following penetrating injury. This may represent a significant indication for follow-up imaging regardless of grade. A larger study will be necessary to identify those most at risk for PSA formation and determine the best PSA screening algorithm.

A majority of trauma-related deep venous thromboses resolve prior to discharge.

Post-traumatic DVTs present unique challenges in patient populations with specific high-risk injury patterns. Duplex ultrasound (US) can be used to assess evolution of DVTs and may guide treatment for high-risk patients. We hypothesized that many DVTs resolve during the initial admission. Weekly duplex US are ordered on all trauma inpatients regardless of prior DVT at our facility. We reviewed US and outcomes data on all patients with lower extremity DVTs at our Level I trauma center from January 2012-December 2021. 392 patients were diagnosed with lower extremity DVT by US. 261 (67%) patients received follow-up US with a mean time to repeat US of 6 days. Of these, 91 (35%) patients experienced DVT resolution prior to the first follow-up US, and 141 (54%) patients experienced resolution prior to discharge. Mean time to resolution was 10 days. Over 50% of DVTs resolve before discharge and are detected by US. Further studies and post-discharge follow-up are needed to determine if patients with resolved DVTs can be managed without therapeutic anticoagulation.

Application of unsupervised deep learning algorithms for identification of specific clusters of chronic cough patients from EMR data.

BACKGROUND: Chronic cough affects approximately 10% of adults. The lack of ICD codes for chronic cough makes it challenging to apply supervised learning methods to predict the characteristics of chronic cough patients, thereby requiring the identification of chronic cough patients by other mechanisms. We developed a deep clustering algorithm with auto-encoder embedding (DCAE) to identify clusters of chronic cough patients based on data from a large cohort of 264,146 patients from the Electronic Medical Records (EMR) system. We constructed features using the diagnosis within the EMR, then built a clustering-oriented loss function directly on embedded features of the deep autoencoder to jointly perform feature refinement and cluster assignment. Lastly, we performed statistical analysis on the identified clusters to characterize the chronic cough patients compared to the non-chronic cough patients. RESULTS: The experimental results show that the DCAE model generated three chronic cough clusters and one non-chronic cough patient cluster. We found various diagnoses, medications, and lab tests highly associated with chronic cough patients by comparing the chronic cough cluster with the non-chronic cough cluster. Comparison of chronic cough clusters demonstrated that certain combinations of medications and diagnoses characterize some chronic cough clusters. CONCLUSIONS: To the best of our knowledge, this study is the first to test the potential of unsupervised deep learning methods for chronic cough investigation, which also shows a great advantage over existing algorithms for patient data clustering.

CHRFAM7A expression in mice increases resiliency after injury.

INTRODUCTION: The CHRNA7 gene encodes the α-7 nicotinic acetylcholine receptor (α7nAchR) that regulates anti-inflammatory responses to injury; however, only humans express a variant gene called CHRFAM7A that alters the function of α7nAChR; CHRFAM7A expression predominates in bone marrow and monocytes/macrophages where the CHRFAM7A/CHRNA7 ratio is highly variable between individuals. We have previously shown in transgenic mice that CHRFAM7A increased emergency myelopoiesis from the bone marrow and monocyte/macrophage expression in lungs. MATERIALS AND METHODS: CHRFAM7A transgenic mice are compared to age- and gender-matched wild-type (WT) siblings. We utilized a model of sepsis using LPS injection to measure survival. Lung vascular permeability was measured after severe burn injury in WT vs. CHRFAM7A transgenic mice. Bone marrow CHRFAM7A expression was evaluated using adoptive transfer of CHRFAM7A transgenic bone marrow into WT mice. RESULTS: Here, we demonstrate that CHRFAM7A expression results in an anti-inflammatory phenotype with an improved survival to LPS and decreased acute lung injury in a severe cutaneous burn model compared to WT. CONCLUSIONS: These data suggest that the relative expression of CHRFAM7A may alter resiliency to injury and contribute to individual variability in the human systemic inflammatory response (SIRS) to injury.

Development of a natural language processing algorithm to detect chronic cough in electronic health records.

BACKGROUND: Chronic cough (CC) is difficult to identify in electronic health records (EHRs) due to the lack of specific diagnostic codes. We developed a natural language processing (NLP) model to identify cough in free-text provider notes in EHRs from multiple health care providers with the objective of using the model in a rules-based CC algorithm to identify individuals with CC from EHRs and to describe the demographic and clinical characteristics of individuals with CC. METHODS: This was a retrospective observational study of enrollees in Optum's Integrated Clinical + Claims Database. Participants were 18-85 years of age with medical and pharmacy health insurance coverage between January 2016 and March 2017. A labeled reference standard data set was constructed by manually annotating 1000 randomly selected provider notes from the EHRs of enrollees with ≥ 1 cough mention. An NLP model was developed to extract positive or negated cough contexts. NLP, cough diagnosis and medications identified cough encounters. Patients with ≥ 3 encounters spanning at least 56 days within 120 days were defined as having CC. RESULTS: The positive predictive value and sensitivity of the NLP algorithm were 0.96 and 0.68, respectively, for positive cough contexts, and 0.96 and 0.84, respectively, for negated cough contexts. Among the 4818 individuals identified as having CC, 37% were identified using NLP-identified cough mentions in provider notes alone, 16% by diagnosis codes and/or written medication orders, and 47% through a combination of provider notes and diagnosis codes/medications. Chronic cough patients were, on average, 61.0 years and 67.0% were female. The most prevalent comorbidities were respiratory infections (75%) and other lower respiratory disease (82%). CONCLUSIONS: Our EHR-based algorithm integrating NLP methodology with structured fields was able to identify a CC population. Machine learning based approaches can therefore aid in patient selection for future CC research studies.

Incidence of acute otitis media in children < 16 years old in Germany during 2014-2019.

BACKGROUND: Acute otitis media (AOM) remains a common infection in children despite the introduction of pneumococcal conjugate vaccines. This study estimated AOM incidence rates (IRs) over time in children < 16 years old in Germany following PCV13 introduction. METHODS: AOM episodes were identified in the InGef healthcare claims database from 2014-2019 in children aged < 16 years. Each AOM episode was classified as either simple or recurrent. Recurrent AOM was defined as 3 or more episodes identified within a 6-month period; or 4 or more episodes within a 12-month period with at least one episode in the prior 6 months. AOM-related surgical procedures within 12 months and complications within 21 days of an AOM episode were also identified. Annual IRs were calculated as number of episodes/child-years (CY) at risk. 95% Confidence intervals (95%CI) were calculated using the Wilson method. The Mann-Kendall test was used to assess trends over time. RESULTS: Between 2014 and 2019, the study population comprised 916,805 children with 327,726 AOM episodes, of which 15% (49,011) of all episodes were identified as recurrent AOM and 85% (278,715) as simple AOM. There were significant declines in AOM (p = 0.003) in the study population overall and in all age groups over the study period; from 101 (95%CI 101-102)/1000 CY to 79 (95%CI 78-80)/1000 CY in the total study population, from 209 (95%CI 206-212)/1000 CY to 147 (95%CI 145-150)/1000 CY in < 2-year-olds, from 239 (95%CI 237-242) to 179 (95%CI 177-182)/1000 CY in 2-4-year-olds, and from 50 (95%CI 49-50) to 38 (95%CI 37-39)/1000 CY in 5-15-year-olds. No significant trends were identified for AOM-related surgical procedures over the study period; however, AOM-related complications overall increased (p = 0.003). CONCLUSION: Between 2014 and 2019, AOM incidence overall declined in children aged 0-15 years in Germany. Over the study period, the incidence of complicated AOM cases increased, however the incidence of AOM-related surgical procedures remained constant. Despite the impact of PCV13, the burden associated with AOM in Germany remains substantial.

An increase in inflammation and islet dysfunction is a feature of prediabetes.

AIMS: Type 2 diabetes (T2D) is a global health problem that will be diagnosed in almost 300 million people by 2025 according to the World Health Organization. Before being diagnosed with T2D, individuals may have glucose levels above normal but below the diabetic range. This condition is known as prediabetes. Studies showed that people with prediabetes had an increase in several pro-inflammatory cytokines in their serum and in their fasting glucose levels. The answer remains unclear when inflammation begins in the pancreas and islets, and what is the extent of this inflammation. METHODS: Subjects with haemoglobin A1c levels from 5.7% to 6.4% were classified as pre-diabetic. Sections of pancreas and isolated islets from normal donors and donors with prediabetes were tested for markers of inflammation and glucose-stimulated insulin secretion (GSIS). RESULTS: Gene and protein expression of the inflammatory markers resistin, interleukin-1 beta, tumour necrosis factor-alpha, interleukin-6, and monocyte chemoattractant protein-1 increased in donors with prediabetes compared to normal donors. GSIS response was significantly decreased in pre-diabetic islets compared to normal islets. Donors with prediabetes also had decreased expression of CD163+ cells but not CD68+ cells. CONCLUSIONS: Based on our findings, inflammation and islet dysfunction may be more significant than originally thought in people with prediabetes. Rather than being in a normal state before diabetes occurs, it appears that subjects are already in an early diabetic condition resembling more closely T2D.

Using Machine Learning to Make Predictions in Patients Who Fall.

BACKGROUND: As the population ages, the incidence of traumatic falls has been increasing. We hypothesize that a machine learning algorithm can more accurately predict mortality after a fall compared with a standard logistic regression (LR) model based on immediately available admission data. Secondary objectives were to predict who would be discharged home and determine which variables had the largest effect on prediction. METHODS: All patients who were admitted for fall between 2012 and 2017 at our level 1 trauma center were reviewed. Fourteen variables describing patient demographics, injury characteristics, and physiology were collected at the time of admission and were used for prediction modeling. Algorithms assessed included LR, decision tree classifier (DTC), and random forest classifier (RFC). Area under the receiver operating characteristic curve (AUC) values were calculated for each algorithm for mortality and discharge to home. RESULTS: About 4725 patients met inclusion criteria. The mean age was 61 ± 20.5 y, Injury Severity Score 8 ± 7, length of stay 5.8 ± 7.6 d, intensive care unit length of stay 1.8± 5.2 d, and ventilator days 0.7 ± 4.2 d. The mortality rate was 3% and three times greater for elderly (aged 65 y and older) patients (5.0% versus 1.6%, P < 0.001). The AUC for predicting mortality for LR, DTC, and RFC was 0.78, 0.64, and 0.86, respectively. The AUC for predicting discharge to home for LR, DTC, and RFC was 0.72, 0.61, and 0.74, respectively. The top five variables that contribute to the prediction of mortality in descending order of importance are the Glasgow Coma Score (GCS) motor, GCS verbal, respiratory rate, GCS eye, and temperature. CONCLUSIONS: RFC can accurately predict mortality and discharge home after a fall. This predictive model can be implemented at the time of patient arrival and may help identify candidates for targeted intervention as well as improve prognostication and resource utilization.

Methamphetamine Use is Associated with Increased Surgical Site Infections after Trauma Laparotomy.

BACKGROUND: Methamphetamine (METH) use causes significant vasoconstriction, which can be severe enough to cause bowel ischemia. Methamphetamines have also been shown to alter the immune response. These effects could predispose METH users to poor wound healing, increased infections, and other post-operative complications. We hypothesized that METH users would have longer length of stay and higher rates of complications compared to non-METH users. METHODS: The trauma registry for our urban Level 1 trauma center was searched for patients that received an exploratory laparotomy from 2016 to 2019. A total 204 patients met criteria and 52 (25.5%) were METH positive. Length of stay (LOS), ventilator days, abbreviated injury scale (AIS), and wound class were compared using nonparametric statistics. Age and injury severity score (ISS) were compared using a Student's t-test. A Chi Square or Fisher's Exact test was used to compare sex, mechanism of injury, and rates of infectious complications. RESULTS: Methamphetamine-positive patients had a significantly higher rate of surgical site infections (7.4% versus 0%, P = 0.001). Patients that developed surgical site infection had equivalent rates of smoking and diabetes, as well as equivalent abdominal AIS and wound class compared to those who did not develop surgical site infection. Hospital and ICU LOS, ventilator days, ISS, and mortality were equivalent between METH positive and negative patients. Rates of other infectious complications were the same between groups. CONCLUSIONS: Methamphetamine use is associated with an increased rate of surgical site infection after trauma laparotomy. Other serious complications and mortality were not affected by METH use.

Crucial role for lung iron level and regulation in the pathogenesis and severity of asthma.

Accumulating evidence highlights links between iron regulation and respiratory disease. Here, we assessed the relationship between iron levels and regulatory responses in clinical and experimental asthma.We show that cell-free iron levels are reduced in the bronchoalveolar lavage (BAL) supernatant of severe or mild-moderate asthma patients and correlate with lower forced expiratory volume in 1 s (FEV1). Conversely, iron-loaded cell numbers were increased in BAL in these patients and with lower FEV1/forced vital capacity (FVC) ratio. The airway tissue expression of the iron sequestration molecules divalent metal transporter 1 (DMT1) and transferrin receptor 1 (TFR1) are increased in asthma, with TFR1 expression correlating with reduced lung function and increased Type-2 (T2) inflammatory responses in the airways. Furthermore, pulmonary iron levels are increased in a house dust mite (HDM)-induced model of experimental asthma in association with augmented Tfr1 expression in airway tissue, similar to human disease. We show that macrophages are the predominant source of increased Tfr1 and Tfr1+ macrophages have increased Il13 expression. We also show that increased iron levels induce increased pro-inflammatory cytokine and/or extracellular matrix (ECM) responses in human airway smooth muscle (ASM) cells and fibroblasts ex vivo and induce key features of asthma in vivo, including airway hyper-responsiveness (AHR) and fibrosis, and T2 inflammatory responses.Together these complementary clinical and experimental data highlight the importance of altered pulmonary iron levels and regulation in asthma, and the need for a greater focus on the role and potential therapeutic targeting of iron in the pathogenesis and severity of disease.

Osteoblasts Are Rapidly Ablated by Virus-Induced Systemic Inflammation following Lymphocytic Choriomeningitis Virus or Pneumonia Virus of Mice Infection in Mice.

A link between inflammatory disease and bone loss is now recognized. However, limited data exist on the impact of virus infection on bone loss and regeneration. Bone loss results from an imbalance in remodeling, the physiological process whereby the skeleton undergoes continual cycles of formation and resorption. The specific molecular and cellular mechanisms linking virus-induced inflammation to bone loss remain unclear. In the current study, we provide evidence that infection of mice with either lymphocytic choriomeningitis virus (LCMV) or pneumonia virus of mice (PVM) resulted in rapid and substantial loss of osteoblasts from the bone surface. Osteoblast ablation was associated with elevated levels of circulating inflammatory cytokines, including TNF-α, IFN-γ, IL-6, and CCL2. Both LCMV and PVM infections resulted in reduced osteoblast-specific gene expression in bone, loss of osteoblasts, and reduced serum markers of bone formation, including osteocalcin and procollagen type 1 N propeptide. Infection of Rag-1-deficient mice (which lack adaptive immune cells) or specific depletion of CD8+ T lymphocytes limited osteoblast loss associated with LCMV infection. By contrast, CD8+ T cell depletion had no apparent impact on osteoblast ablation in association with PVM infection. In summary, our data demonstrate dramatic loss of osteoblasts in response to virus infection and associated systemic inflammation. Further, the inflammatory mechanisms mediating viral infection-induced bone loss depend on the specific inflammatory condition.

3D Bioprinted Osteogenic Tissue Models for In Vitro Drug Screening.

Metabolic bone disease affects hundreds of millions of people worldwide, and as a result, in vitro models of bone tissue have become essential tools to help analyze bone pathogenesis, develop drug screening, and test potential therapeutic strategies. Drugs that either promote or impair bone formation are in high demand for the treatment of metabolic bone diseases. These drugs work by targeting numerous signaling pathways responsible for regulating osteogenesis such as Hedgehog, Wnt/ß-catenin, and PI3K-AKT. In this study, differentiated bone marrow-derived mesenchymal stem cell (BM-MSC) scaffold-free 3D bioprinted constructs and 2D monolayer cultures were utilized to screen four drugs predicted to either promote (Icariin and Purmorphamine) or impair osteogenesis (PD98059 and U0126). Osteogenic differentiation capacity was analyzed over a four week culture period by evaluating mineralization, alkaline phosphatase (ALP) activity, and osteogenesis related gene expression. Responses to drug treatment were observed in both 3D differentiated constructs and 2D monolayer cultures. After four weeks in culture, 3D differentiated constructs and 2D monolayer cultures treated with Icariin or Purmorphamine showed increased mineralization, ALP activity, and the gene expression of bone formation markers (BGLAP, SSP1, and COL1A1), signaling molecules (MAPK1, WNT1, and AKT1), and transcription factors (RUNX2 and GLI1) that regulate osteogenic differentiation relative to untreated. 3D differentiated constructs and 2D monolayer cultures treated with PD98059 or U0126 showed decreased mineralization, ALP activity, and the expression of the aforementioned genes BGLAP, SPP1, COL1A1, MAPK1, AKT1, RUNX2, and GLI1 relative to untreated. Differences in ALP activity and osteogenesis related gene expression relative to untreated cells cultured in a 2D monolayer were greater in 3D constructs compared to 2D monolayer cultures. These findings suggest that our bioprinted bone model system offers a more sensitive, biologically relevant drug screening platform than traditional 2D monolayer in vitro testing platforms.

Synthetic poly(ethylene glycol)-based microfluidic islet encapsulation reduces graft volume for delivery to highly vascularized and retrievable transplant site.

Transplant of hydrogel-encapsulated allogeneic islets has been explored to reduce or eliminate the need for chronic systemic immunosuppression by creating a physical barrier that prevents direct antigen presentation. Although successful in rodents, translation of alginate microencapsulation to large animals and humans has been hindered by large capsule sizes (≥500 µm diameter) that result in suboptimal nutrient diffusion in the intraperitoneal space. We developed a microfluidic encapsulation system that generates synthetic poly(ethylene glycol)-based microgels with smaller diameters (310 ± 14 µm) that improve encapsulated islet insulin responsiveness over alginate capsules and allow transplant within vascularized tissue spaces, thereby reducing islet mass requirements and graft volumes. By delivering poly(ethylene glycol)-encapsulated islets to an isolated, retrievable, and highly vascularized site via a vasculogenic delivery vehicle, we demonstrate that a single pancreatic donor syngeneic islet mass exhibits improved long-term function over conventional alginate capsules and close integration with transplant site vasculature. In vivo tracking of bioluminescent allogeneic encapsulated islets in an autoimmune type 1 diabetes murine model showed enhanced cell survival over unencapsulated islets in the absence of chronic systemic immunosuppression. This method demonstrates a translatable alternative to intraperitoneal encapsulated islet transplant.

Local immunomodulation Fas ligand-engineered biomaterials achieves allogeneic islet graft acceptance.

Islet transplantation is a promising therapy for type 1 diabetes. However, chronic immunosuppression to control rejection of allogeneic islets induces morbidities and impairs islet function. T effector cells are responsible for islet allograft rejection and express Fas death receptors following activation, becoming sensitive to Fas-mediated apoptosis. Here, we report that localized immunomodulation using microgels presenting an apoptotic form of the Fas ligand with streptavidin (SA-FasL) results in prolonged survival of allogeneic islet grafts in diabetic mice. A short course of rapamycin treatment boosted the immunomodulatory efficacy of SA-FasL microgels, resulting in acceptance and function of allografts over 200 days. Survivors generated normal systemic responses to donor antigens, implying immune privilege of the graft, and had increased CD4+CD25+FoxP3+ T regulatory cells in the graft and draining lymph nodes. Deletion of T regulatory cells resulted in acute rejection of established islet allografts. This localized immunomodulatory biomaterial-enabled approach may provide an alternative to chronic immunosuppression for clinical islet transplantation.

Th22 Cells Form a Distinct Th Lineage from Th17 Cells In Vitro with Unique Transcriptional Properties and Tbet-Dependent Th1 Plasticity.

Th22 cells are a major source of IL-22 and have been found at sites of infection and in a range of inflammatory diseases. However, their molecular characteristics and functional roles remain largely unknown because of our inability to generate and isolate pure populations. We developed a novel Th22 differentiation assay and generated dual IL-22/IL-17A reporter mice to isolate and compare pure populations of cultured Th22 and Th17 cells. Il17a fate-mapping and transcriptional profiling provide evidence that these Th22 cells have never expressed IL-17A, suggesting that they are potentially a distinct cell lineage from Th17 cells under in vitro culture conditions. Interestingly, Th22 cells also expressed granzymes, IL-13, and increased levels of Tbet. Using transcription factor-deficient cells, we demonstrate that RORγt and Tbet act as positive and negative regulators of Th22 differentiation, respectively. Furthermore, under Th1 culture conditions in vitro, as well as in an IFN-γ-rich inflammatory environment in vivo, Th22 cells displayed marked plasticity toward IFN-γ production. Th22 cells also displayed plasticity under Th2 conditions in vitro by upregulating IL-13 expression. Our work has identified conditions to generate and characterize Th22 cells in vitro. Further, it provides evidence that Th22 cells develop independently of the Th17 lineage, while demonstrating plasticity toward both Th1- and Th2-type cells.

Direct peritoneal resuscitation reduces inflammation in the kidney after acute brain death.

Brain death is associated with significant inflammation within the kidneys, which may contribute to reduced graft survival. Direct peritoneal resuscitation (DPR) has been shown to reduce systemic inflammation after brain death. To determine its effects, brain dead rats were resuscitated with normal saline (targeted intravenous fluid) to maintain a mean arterial pressure of 80 mmHg; DPR animals also received 30 cc of intraperitoneal peritoneal dialysis solution. Rats were euthanized at 0, 2, 4, and 6 h after brain death. Pro-inflammatory cytokines were measured using ELISA. Levels of IL-1ß, TNF-α, and IL-6 in the kidney were significantly increased as early as 2 h after brain death and significantly decreased with DPR. Levels of leukocyte adhesion molecules ICAM and VCAM increased after brain death and were decreased with DPR (ICAM 2.33 ± 0.14 vs. 0.42 ± 0.04, P = 0.002; VCAM 82.6 ± 5.8 vs. 37.3 ± 1.9, P = 0.002 at 4 h) as were E-selectin and P-selectin (E-selectin 25,605 vs. 16,144, P = 0.005; P-selectin 82.5 ± 3.3 vs. 71.0 ± 2.3, P = 0.009 at 4 h). Use of DPR reduces inflammation and adhesion molecule expression in the kidneys, and is associated with reduced macrophages and neutrophils on immunohistochemistry. Using DPR in brain dead donors has the potential to reduce the immunologic activity of transplanted kidneys and could improve graft survival.

Damage-associated molecular patterns in resuscitated hemorrhagic shock are mitigated by peritoneal fluid administration.

Conventional resuscitation (CR) of hemorrhagic shock (HS), a significant cause of trauma mortality, is intravenous blood and fluids. CR restores central hemodynamics, but vital organ flow can drop, causing hypoperfusion, hypoxia, damage-associated molecular patterns (DAMPs), and remote organ dysfunction (i.e., lung). CR plus direct peritoneal resuscitation (DPR) prevents intestinal and hepatic hypoperfusion. We hypothesized that DPR prevents lung injury in HS/CR by altering DAMPs. Anesthetized male Sprague-Dawley rats were randomized to groups ( n = 8/group) in one of two sets: 1) sham (no HS, CR, or DPR), 2) HS/CR (HS = 40% mean arterial pressure (MAP) for 60 min, CR = shed blood + 2 volumes normal saline), or 3) HS/CR + DPR. The first set underwent whole lung blood flow by colorimetric microspheres. The second set underwent tissue collection for Luminex, ELISAs, and histopathology. Lipopolysaccharide (LPS) and DAMPs were measured in serum and/or lung, including cytokines, hyaluronic acid (HA), high-mobility group box 1 (HMGB1), Toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 protein (MYD88), and TIR-domain-containing adapter-inducing interferon-ß (TRIF). Statistics were by ANOVA and Tukey-Kramer test with a priori P < 0.05. HS/CR increased serum LPS, HA, HMGB1, and some cytokines [interleukin (IL)-1α, IL-1ß, IL-6, and interferon-γ]. Lung TLR4 and MYD88 were increased but not TRIF compared with Shams. HS/CR + DPR decreased LPS, HA, cytokines, HMGB1, TLR4, and MYD88 levels but did not alter TRIF compared with HS/CR. The data suggest that gut-derived DAMPs can be modulated by adjunctive DPR to prevent activation of lung TLR-4-mediated processes. Also, DPR improved lung blood flow and reduced lung tissue injury. Adjunctive DPR in HS/CR potentially improves morbidity and mortality by downregulating the systemic DAMP response.