Distinct olfactory mucosal macrophage populations mediate neuronal maintenance and pathogen defense.

The olfactory mucosa is important for both the sense of smell and as a mucosal immune barrier to the upper airway and brain. However, little is known about how the immune system mediates the conflicting goals of neuronal maintenance and inflammation in this tissue. A number of immune cell populations reside within the olfactory mucosa and yet we have little understanding of how these resident olfactory immune cells functionally interact with the chemosensory environment. Identifying these interactions will allow therapeutic manipulations that treat disorders such as post-viral olfactory dysfunction. Macrophages are the most prevalent immune cell type in the uninflamed olfactory mucosa and here, we identify two distinct tissue macrophage populations in murine olfactory mucosa. P2ry12hi macrophages are transcriptionally specialized for neuron interactions, closely associated with olfactory neuron cell bodies, long-term tissue residents, and functionally specialized to phagocytose cells and debris, including olfactory neurons. Conversely, MHC Class IIhi macrophages are transcriptionally dedicated to cytokine production and antigen presentation, localized primarily within the olfactory lamina propria, more rapidly replaced by blood monocytes, and rapidly produce chemokines in response to viral infection. We further show that these macrophage signatures are present in human olfactory biopsies, and P2ry12-like olfactory macrophages are reduced in patients with long-term smell loss following COVID-19. Together, these data show that two olfactory macrophage populations regulate neurons and initiate the immune response, contributing to our understanding of both olfactory immunity and tissue-resident macrophage biology.

Interleukin-1ß/Interleukin (IL)-1-Receptor-Antagonist (IL1-RA) Axis in Invasive Bladder Cancer-An Exploratory Analysis of Clinical and Tumor Biological Significance.

Previous data indicate a role of IL-1 and IL-1RA imbalance in bladder carcinoma (BC); the inhibition of IL-1 signaling might be considered a treatment option. Objective: To assess expression patterns and the prognostic role of IL-1ß and IL-1RA in invasive BC and to evaluate their interaction with AKT signaling and proliferation. The study included two independent cohorts of n = 92 and n = 102 patients who underwent a radical cystectomy for BC. Specimen from BC and benign urothelium (n = 22 and n = 39) were processed to a tissue microarray and immunohistochemically stained for IL-1ß, IL-1RA, AKT, and Ki-67. Expression scores were correlated to clinical variables and Ki-67 and AKT expression. An association with outcome was assessed using Wilcoxon Kruskal-Wallis tests, Chi-square tests or linear regression, dependent on the variable's category. Kaplan-Meier and Cox proportional hazard analyses were used to estimate recurrence-free (RFS), cancer-specific (CSS) and overall survival (OS). Both IL-1ß and IL-1RA were significantly overexpressed in invasive BC compared to benign urothelium in both cohorts (p < 0.005). IL-1ß was associated with vascular invasion (210 vs. 183, p < 0.02), lymphatic invasion (210 vs. 180, <0.05) and G3 cancer (192 vs. 188, <0.04). The survival analysis revealed favorable RFS, CSS, and OS in the case of high IL-1ß expression (p < 0.02, <0.03, and <0.006, respectively). Multivariate analyses revealed an independent impact of (low) IL1ß expression on RFS, CSS, and OS. The IL-1ß and IL-1ß/IL-1RA ratios were positively correlated to the AKT expression (p < 0.05 and <0.01, respectively). Additionally, the high expression of Ki-67 (>15%) correlated with higher levels of IL-1ß (p = 0.01). The overexpression of IL-1ß and IL-1RA is frequently found in BC, with a prognostic significance observed for the IL-1ß protein expression. The observed link between the IL-1ß/IL-1RA axis and AKT signaling may indicate possible autophagy activation processes besides the known tumor-promoting effects of AKT.

How to treat jatrogenic ureteral injury after posterior spinal surgery? Case report and review of literature.

Introduction: Entry into the retroperitoneal space during open posterior spinal surgery introduces the rare possibility of iatrogenic ureteral injury. Case presentation: We describe a case of ureteral injury after spinal surgery in a 49-year-old female with persistent lumbar pain and high fever 2 weeks after spinal surgery. After admission to the urology department, a computer tomography scan was performed and revealed right-side hydronephrosis grade III and large retroperitoneal fluid collection. After radiological confirmation of right ureteral injury, a ureteral stent was placed, but 4 weeks later, ureteral stricture was confirmed on antegrade pyelography. Therefore, surgical ureteroplasty was indicated 2 months after initial admission to the urology department. Six weeks later, the stent was removed, and intravenous pyelography revealed a normal ureteral passage. Conclusion: There should be a low threshold for ureteral injuries after spinal cord surgery in patients with high fever and elevated blood creatinine levels.

Mini-laparotomy radical cystectomy with limited bowel externalization during ileal conduit urinary diversion reduces the rate of postoperative complications: a match-paired, single centered analysis.

OBJECTIVE: To assess the feasibility and functional outcomes of mini-laparotomy radical cystectomy (RC) in association with limited bowel externalization during ileal conduit urinary diversion. METHODS: Between January 2018 and March 2020, 53 patients underwent RC plus pelvic lymph node dissection (PLND) for invasive carcinoma of the urinary bladder. This group of patients was intentionally treated utilizing the mini-laparotomy approach, with the addition of limited bowel externalization during conduit preparation and match-paired with 46 examinees from a historical series of patients who underwent conventional open RC plus PLND and ileal conduit diversion. Clinicopathological features and perioperative outcomes were examined from medical records, while postoperative pain was evaluated through the Visual Analog Scale for Pain (VAS). Mean pain scores were evaluated on postoperative days (POD) 1-3. RESULTS: There was no difference in specific intraoperative complications between groups, with a median (range) incision length of 8 (5-10) cm within the first group and 16.3 (12-22.6) cm within the second group. The first group had less postoperative pain compared with patients in the second group, with mean pain scores significantly lower across POD 1-3, 3.8 (IQR: 0-6) versus 6.7 (IQR: 3.8-8.1) and 2.5 (IQR: 1-3.7) versus 4.6 (IQR: 3-6), respectively (p = .012 and .002). CONCLUSIONS: By using this technique, we were able to significantly reduce patients' postoperative pain, time to bowel restitution, and hospital stay, which are major issues in minimizing short-term postoperative complications of conventional open surgery.

Sociodemographic Characteristics and the Influence of Religion on the Knowledge of Doctors, Nurses, and the General Population in Montenegro About Transplant and Organ Donation.

OBJECTIVES: The goal of our research was to determine the level of knowledge of healthcare workers and the general population about transplantation and organ donation through sociodemographic and religious aspects. MATERIALS AND METHODS: We conducted a cross-sectional study to provide insight on the knowledge of doctors, nurses, and the general population in Montenegro about organ transplantation and donation. We had 400 respondents (200 doctors and nurses and 200 people from the general population) who were surveyed and who signed informed consent to participate in the study. RESULTS: In the analysis of knowledge about organ donation, significant differences were shown in the number of total correct answers between the 2 groups of respondents. Respondents from monotheistic, Montenegrin Orthodox, Catholic, and Islamic religious groups had the same percentage of correct answers, with no significant differences between these groups. Although respondents older than 56 years were the least informed about the term "organ donation," 21.1% stated thatthey would donate organs regardless of the circumstances; 5.2% of respondents between age 46 and 55 years also stated they would donate organs regardless of the circumstances. With regard to this parameter, significant differences were shown between respondents in different age groups. CONCLUSIONS: Healthcare workers had a higher level of knowledge about organ transplant and donation compared with the general population, which is justified by the gaps in education among the general population. In both healthcare workers and the general population, religion had no significant influence on the level of knowledge about transplantation.

Assessment of Various Machine Learning Models for Peach Maturity Prediction Using Non-Destructive Sensor Data.

To date, many machine learning models have been used for peach maturity prediction using non-destructive data, but no performance comparison of the models on these datasets has been conducted. In this study, eight machine learning models were trained on a dataset containing data from 180 'Suncrest' peaches. Before the models were trained, the dataset was subjected to dimensionality reduction using the least absolute shrinkage and selection operator (LASSO) regularization, and 8 input variables (out of 29) were chosen. At the same time, a subgroup consisting of the peach ground color measurements was singled out by dividing the set of variables into three subgroups and by using group LASSO regularization. This type of variable subgroup selection provided valuable information on the contribution of specific groups of peach traits to the maturity prediction. The area under the receiver operating characteristic curve (AUC) values of the selected models were compared, and the artificial neural network (ANN) model achieved the best performance, with an average AUC of 0.782. The second-best machine learning model was linear discriminant analysis with an AUC of 0.766, followed by logistic regression, gradient boosting machine, random forest, support vector machines, a classification and regression trees model, and k-nearest neighbors. Although the primary parameter used to determine the performance of the model was AUC, accuracy, F1 score, and kappa served as control parameters and ultimately confirmed the obtained results. By outperforming other models, ANN proved to be the most accurate model for peach maturity prediction on the given dataset.

Single-cell profiling of environmental enteropathy reveals signatures of epithelial remodeling and immune activation.

Environmental enteropathy (EE) is a subclinical condition of the small intestine that is highly prevalent in low- and middle-income countries. It is thought to be a key contributing factor to childhood malnutrition, growth stunting, and diminished oral vaccine responses. Although EE has been shown to be the by-product of a recurrent enteric infection, its full pathophysiology remains unclear. Here, we mapped the cellular and molecular correlates of EE by performing high-throughput, single-cell RNA-sequencing on 33 small intestinal biopsies from 11 adults with EE in Lusaka, Zambia (eight HIV-negative and three HIV-positive), six adults without EE in Boston, United States, and two adults in Durban, South Africa, which we complemented with published data from three additional individuals from the same clinical site. We analyzed previously defined bulk-transcriptomic signatures of reduced villus height and decreased microbial translocation in EE and showed that these signatures may be driven by an increased abundance of surface mucosal cells-a gastric-like subset previously implicated in epithelial repair in the gastrointestinal tract. In addition, we determined cell subsets whose fractional abundances associate with EE severity, small intestinal region, and HIV infection. Furthermore, by comparing duodenal EE samples with those from three control cohorts, we identified dysregulated WNT and MAPK signaling in the EE epithelium and increased proinflammatory cytokine gene expression in a T cell subset highly expressing a transcriptional signature of tissue-resident memory cells in the EE cohort. Together, our work elucidates epithelial and immune correlates of EE and nominates cellular and molecular targets for intervention.

Screening for modulators of the cellular composition of gut epithelia via organoid models of intestinal stem cell differentiation.

The cellular composition of barrier epithelia is essential to organismal homoeostasis. In particular, within the small intestine, adult stem cells establish tissue cellularity, and may provide a means to control the abundance and quality of specialized epithelial cells. Yet, methods for the identification of biological targets regulating epithelial composition and function, and of small molecules modulating them, are lacking. Here we show that druggable biological targets and small-molecule regulators of intestinal stem cell differentiation can be identified via multiplexed phenotypic screening using thousands of miniaturized organoid models of intestinal stem cell differentiation into Paneth cells, and validated via longitudinal single-cell RNA-sequencing. We found that inhibitors of the nuclear exporter Exportin 1 modulate the fate of intestinal stem cells, independently of known differentiation cues, significantly increasing the abundance of Paneth cells in the organoids and in wild-type mice. Physiological organoid models of the differentiation of intestinal stem cells could find broader utility for the screening of biological targets and small molecules that can modulate the composition and function of other barrier epithelia.

'Burned-Out' primary testicular tumour: Is retroperitoneal lymph node biopsy mandatory prior to initiation of chemotherapy? Report of three cases and a review of the literature.

The term 'burned-out' tumour of the testis describes a spontaneously and completely regressed testicular tumour that presents at the stage of metastasis. We report three cases of burned-out testicular tumour to illustrate their clinical, radiological and histopathological features and to discuss the hypothesis of the efficacy of early adjuvant chemotherapy without a previous retroperitoneal lymph node biopsy. Subsequent to radical orchiectomy, each pathohistology report revealed testicular hypotrophy or microcalcifications, with no clearly visible germ cell tumours within the specimen. Additionally, following surgery, the patients received the standard (cisplatin-etoposide-bleomycin) chemotherapy protocol, which in two out of three cases showed a complete response. Only one examinee revealed a partial response and received salvage chemotherapy, but he remained in the remission phase during the last follow-up. This study illustrates the value of the early administration of adjuvant chemotherapy in patients with burned-out testicular tumour, which offers the possibility of omitting the diagnostic retroperitoneal lymph node biopsy. Considering the low threshold for testicular malignancy, it is clearly of the utmost importance that these rare patients be treated in a timely manner and without adjunctive procedures (lymph node biopsy) leading to additional morbidity.

Technique selection of ureteroileal anastomosis in hautmann ileal neobladder with chimney modification: Reliability of patient-based selection strategy and its impact on ureteroentric stricture rate.

OBJECTIVE: We aimed to establish the reliability of technique selection strategy for ureteroileal anastomosis (Bricker vs. Wallace) by comparing perioperative outcomes, complications, and anastomotic stricture rate in a contemporary series of patients who underwent open radical cystectomy followed by reconstruction of modified Hautmann neobladder. MATERIALS AND METHODS: A total of 60 patients underwent radical cystectomy and modified Hautmann neobladder, of whom 30 patients (group I) with Bricker anastomotic technique were compared to 30 matched paired patients with end-to-end ureteroileal anastomosis (group II). Long-term results, including ureteroileal stricture (UIS) and postoperative complication rate at two year follow up were available. The choice of anastomosis type was successively based on chimney size, ureteral length after retro-sigmoidal tunneling and diameter of distal ureter. Postoperative complications were graded according to the Clavien-Dindo system. RESULTS: Ureteroileal stricture rate was 6.6% in group I vs. 0% in group II, after three months (p < 0.05), while anastomotic leakage rate was 6.6% vs. 3.3% (group I vs group II) between the two groups for the same follow up period (p > 0.05). High-grade complications (Clavien III-V) were more in Bricker group as compared to Wallace group and the difference was significant (20% vs 10.3%, p = 0.03). CONCLUSION: Our preliminary outcomes demonstrate that this selection strategy seems to be clinically reliable, with lower incidence of postoperative complications in Wallace group.

Anti-arthritic effect of chicken embryo tissue hydrolyzate against adjuvant arthritis in rats (X-ray microtomographic and histopathological analysis).

Finding new, safe strategies to prevent and control rheumatoid arthritis is an urgent task. Bioactive peptides and peptide-rich protein hydrolyzate represent a new trend in the development of functional foods and nutraceuticals. The resulting tissue hydrolyzate of the chicken embryo (CETH) has been evaluated for acute toxicity and tested against chronic arthritis induced by Freund's full adjuvant (modified Mycobacterium butyricum) in rats. The antiarthritic effect of CETH was studied on the 28th day of the experiment after 2 weeks of oral administration of CETH at doses of 60 and 120 mg/kg body weight. Arthritis was evaluated on the last day of the experiment on the injected animal paw using X-ray computerized microtomography and histopathology analysis methods. The CETH effect was compared with the non-steroidal anti-inflammatory drug diclofenac sodium (5 mg/kg). Oral administration of CETH was accompanied by effective dose-dependent correction of morphological changes caused by the adjuvant injection. CETH had relatively high recovery effects in terms of parameters for reducing inflammation, inhibition of osteolysis, reduction in the inflammatory reaction of periarticular tissues, and cartilage degeneration. This study presents for the first time that CETH may be a powerful potential nutraceutical agent or bioactive component in the treatment of rheumatoid arthritis.

Mepolizumab targets multiple immune cells in aspirin-exacerbated respiratory disease.

BACKGROUND: Eosinophilic asthma and nasal polyposis are hallmarks of aspirin-exacerbated respiratory disease (AERD), and IL-5 inhibition has been shown to provide therapeutic benefit. However, IL-5Rα is expressed on many cells in addition to eosinophils, and the mechanisms by which IL-5 inhibition leads to clinical benefit in eosinophilic asthma and nasal polyposis are unlikely to be due exclusively to antieosinophil effects. OBJECTIVE: We sought to identify the mechanisms by which anti-IL-5 treatment with mepolizumab improves respiratory inflammation in AERD. METHODS: The clinical characteristics, circulating granulocytes, nasal scraping transcripts, eosinophilic cationic protein, tryptase, and antibody levels, and urinary and nasal eicosanoid levels were measured for 18 subjects with AERD who were taking mepolizumab and compared with those of 18 matched subjects with AERD who were not taking mepolizumab. RESULTS: Subjects taking mepolizumab had significantly fewer peripheral blood eosinophils and basophils, and those cells that remained had higher surface CRTH2 expression than did the cells from subjects not taking mepolizumab. Nasal prostaglandin F2α, prostaglandin D2 metabolites, leukotriene B4, and thromboxane levels were lower in subjects taking mepolizumab, as were urinary levels of tetranor-prostaglandin D2 and leukotriene E4. The nasal epithelial cell transcripts that were overexpressed among subjects with AERD who were taking mepolizumab were enriched for genes involved in tight junction formation and cilium organization. Nasal and urinary prostaglandin E2, tryptase, and antibody levels were not different between the 2 groups. CONCLUSION: IL-5 inhibition in AERD decreases production of inflammatory eicosanoids and upregulates tight junction-associated nasal epithelial cell transcripts, likely due to decreased IL-5 signaling on tissue mast cells, eosinophils, and epithelial cells. These direct effects on multiple relevant immune cells contribute to the mechanism of benefit afforded by mepolizumab.

Functional results of hautmann neobladder with chimney modification and wallace ureteroileal anastomosis: initial experience with 22 patients

ABSTRACT Objective: To assess the functional outcomes and complications of modified Hautmann neobladder with Wallace ureteroileal anastomosis on a 6-8 cm long isoperistaltic chimney, following radical cystectomy. Materials and Methods: Between January 2015 and October 2019, 22 patients (18 men and 4 women) underwent radical cystectomy and Hautmann neobladder reconstruction with chimney modification and Wallace I ureteroileal anastomosis. The mean age of patients was 61 years (45-74 years). All procedures were performed by the same surgeon and the mean follow-up was 29.4 months. Complications were registered as early (occurring within 3 months) or late (occurring after 3 months), with particular attention addressed to the ureteroileal anastomotic stricture and anastomotic leakage rate. Patient evaluation also included symptom analysis for daytime continence and voiding frequency. Results: Ureteroileal anastomotic stricture was not detected as a cause of hydronephrosis. Hovewer, the anastomotic leakage occurred in one patient during the early postoperative period. Early complications occurred in 9 patients and the most common was bilateral hydronephrosis, detected in 5 examinees. Late complications occurred in 4 patients. Complete daytime and nighttime continence achieved in 18 and 16 patients respectively, with two patients (9%) still required intermittent catheterization three months after surgery. Conclusions: The functional results with modified Hautmann neobladder, incorporating short afferent limb in Wallace I uretero-enteric anastomosis, were efficient. This technique is an effective way to minimize potential uretero-enteric stricture, anastomotic leakage and incidence of vesicoureteral reflux.

Human airway mast cells proliferate and acquire distinct inflammation-driven phenotypes during type 2 inflammation.

Mast cells (MCs) play a pathobiologic role in type 2 (T2) allergic inflammatory diseases of the airway, including asthma and chronic rhinosinusitis with nasal polyposis (CRSwNP). Distinct MC subsets infiltrate the airway mucosa in T2 disease, including subepithelial MCs expressing the proteases tryptase and chymase (MCTC) and epithelial MCs expressing tryptase without chymase (MCT). However, mechanisms underlying MC expansion and the transcriptional programs underlying their heterogeneity are poorly understood. Here, we use flow cytometry and single-cell RNA-sequencing (scRNA-seq) to conduct a comprehensive analysis of human MC hyperplasia in CRSwNP, a T2 cytokine-mediated inflammatory disease. We link discrete cell surface phenotypes to the distinct transcriptomes of CRSwNP MCT and MCTC, which represent polarized ends of a transcriptional gradient of nasal polyp MCs. We find a subepithelial population of CD38highCD117high MCs that is markedly expanded during T2 inflammation. These CD38highCD117high MCs exhibit an intermediate phenotype relative to the expanded MCT and MCTC subsets. CD38highCD117high MCs are distinct from circulating MC progenitors and are enriched for proliferation, which is markedly increased in CRSwNP patients with aspirin-exacerbated respiratory disease, a severe disease subset characterized by increased MC burden and elevated MC activation. We observe that MCs expressing a polyp MCT-like effector program are also found within the lung during fibrotic diseases and asthma, and further identify marked differences between MCTC in nasal polyps and skin. These results indicate that MCs display distinct inflammation-associated effector programs and suggest that in situ MC proliferation is a major component of MC hyperplasia in human T2 inflammation.

Lymph nodes are innervated by a unique population of sensory neurons with immunomodulatory potential.

Barrier tissue immune responses are regulated in part by nociceptors. Nociceptor ablation alters local immune responses at peripheral sites and within draining lymph nodes (LNs). The mechanisms and significance of nociceptor-dependent modulation of LN function are unknown. Using high-resolution imaging, viral tracing, single-cell transcriptomics, and optogenetics, we identified and functionally tested a sensory neuro-immune circuit that is responsive to lymph-borne inflammatory signals. Transcriptomics profiling revealed that multiple sensory neuron subsets, predominantly peptidergic nociceptors, innervate LNs, distinct from those innervating surrounding skin. To uncover LN-resident cells that may interact with LN-innervating sensory neurons, we generated a LN single-cell transcriptomics atlas and nominated nociceptor target populations and interaction modalities. Optogenetic stimulation of LN-innervating sensory fibers triggered rapid transcriptional changes in the predicted interacting cell types, particularly endothelium, stromal cells, and innate leukocytes. Thus, a unique population of sensory neurons monitors peripheral LNs and may locally regulate gene expression.

Functional results of hautmann neobladder with chimney modification and wallace ureteroileal anastomosis: initial experience with 22 patients.

OBJECTIVE: To assess the functional outcomes and complications of modified Hautmann neobladder with Wallace ureteroileal anastomosis on a 6-8 cm long isoperistaltic chimney, following radical cystectomy. MATERIALS AND METHODS: Between January 2015 and October 2019, 22 patients (18 men and 4 women) underwent radical cystectomy and Hautmann neobladder reconstruction with chimney modification and Wallace I ureteroileal anastomosis. The mean age of patients was 61 years (45-74 years). All procedures were performed by the same surgeon and the mean follow-up was 29.4 months. Complications were registered as early (occurring within 3 months) or late (occurring after 3 months), with particular attention addressed to the ureteroileal anastomotic stricture and anastomotic leakage rate. Patient evaluation also included symptom analysis for daytime continence and voiding frequency. RESULTS: Ureteroileal anastomotic stricture was not detected as a cause of hydronephrosis. Hovewer, the anastomotic leakage occurred in one patient during the early postoperative period. Early complications occurred in 9 patients and the most common was bilateral hydronephrosis, detected in 5 examinees. Late complications occurred in 4 patients. Complete daytime and nighttime continence achieved in 18 and 16 patients respectively, with two patients (9%) still required intermittent catheterization three months after surgery. CONCLUSIONS: The functional results with modified Hautmann neobladder, incorporating short afferent limb in Wallace I uretero-enteric anastomosis, were efficient. This technique is an effective way to minimize potential uretero-enteric stricture, anastomotic leakage and incidence of vesicoureteral reflux.

Modified Wallace anastomotic technique reduces ureteroenteric stricture rates after ileal conduit urinary diversion

ABSTRACT Purpose: To compare perioperative outcomes, complications and anastomotic stricture rate in a contemporary series of patients who underwent open radical cystectomy (RC) with modified Wallace anastomotic technique versus traditional ileal conduit. Materials and methods: Study enrolled 180 patients, of whom 140 were randomized and underwent RC; seventy were randomized to group I and the seventy to the group II. For the primary objective, we hypothesized that the rate of ureteroenteric strictures would be at least 20 % lower in the second group. Secondary end points included rate of anastomotic leak, surgical time, deterioration of the upper tract, intraoperative blood loss and patient-reported quality of life (HRQOL). The modified Wallace 1 technique involved eversion of the ureteral plate and bowel mucosa edges, which were anastomosed together in running fashion, while the outher anastomotic wall was augmented with sero-serosal interrupted sutures. Results: The mean (SD) follow-up time was 26.1 (5.7) months in group I and 25.2 (4.8) months in group II, during which, anastomotic stricture was observed in 8 patients (12%) from the first and 2 patients (3%) from the second group (p < 0.05). The anastomotic leakage rate was significantly higher in first group (17% vs. 8.5%, p< 0.05), while patient-reported HRQOL outcomes were similar between groups after the 12 month follow-up period. Conclusions: By using a modified Wallace technique, we were able to significantly lower anastomotic stricture and anastomotic leakage rates, which are major issues in minimizing both short- and long-term postoperative complications.

Single-Cell Analyses of Colon and Blood Reveal Distinct Immune Cell Signatures of Ulcerative Colitis and Crohn's Disease.

BACKGROUND & AIMS: Studies are needed to determine the mechanisms of mucosal dysregulation in patients with inflammatory bowel diseases (IBDs) and differences in inflammatory responses of patients with ulcerative colitis (UC) vs Crohn's disease (CD). We used mass cytometry (CyTOF) to characterize and compare immune cell populations in the mucosa and blood from patients with IBD and without IBD (controls) at single-cell resolution. METHODS: We performed CyTOF analysis of colonic mucosa samples (n = 87) and peripheral blood mononuclear cells (n = 85) from patients with active or inactive UC or CD and controls. We also performed single-cell RNA sequencing, flow cytometry, and RNA in situ hybridization analyses to validate key findings. We used random forest modeling to identify differences in signatures across subject groups. RESULTS: Compared with controls, colonic mucosa samples from patients with IBD had increased abundances of HLA-DR+CD38+ T cells, including T-regulatory cells that produce inflammatory cytokines; CXCR3+ plasmablasts; and IL1B+ macrophages and monocytes. Colonic mucosa samples from patients with UC were characterized by expansion of IL17A+ CD161+ effector memory T cells and IL17A+ T-regulatory cells; expansion of HLA-DR+CD56+ granulocytes; and reductions in type 3 innate lymphoid cells. Mucosal samples from patients with active CD were characterized by IL1B+HLA-DR+CD38+ T cells, IL1B+TNF+IFNG+ naïve B cells, IL1B+ dendritic cells (DCs), and IL1B+ plasmacytoid DCs. Peripheral blood mononuclear cells from patients with active CD differed from those of active UC in that the peripheral blood mononuclear cells from patients with CD had increased IL1B+ T-regulatory cells, IL1B+ DCs and IL1B+ plasmacytoid DCs, IL1B+ monocytes, and fewer group 1 innate lymphoid cells. Random forest modeling differentiated active UC from active CD in colonic mucosa and blood samples; top discriminating features included many of the cellular populations identified above. CONCLUSIONS: We used single-cell technologies to identify immune cell populations specific to mucosa and blood samples from patients with active or inactive CD and UC and controls. This information might be used to develop therapies that target specific cell populations in patients with different types of IBD.

SARS-CoV-2 Receptor ACE2 Is an Interferon-Stimulated Gene in Human Airway Epithelial Cells and Is Detected in Specific Cell Subsets across Tissues.

There is pressing urgency to understand the pathogenesis of the severe acute respiratory syndrome coronavirus clade 2 (SARS-CoV-2), which causes the disease COVID-19. SARS-CoV-2 spike (S) protein binds angiotensin-converting enzyme 2 (ACE2), and in concert with host proteases, principally transmembrane serine protease 2 (TMPRSS2), promotes cellular entry. The cell subsets targeted by SARS-CoV-2 in host tissues and the factors that regulate ACE2 expression remain unknown. Here, we leverage human, non-human primate, and mouse single-cell RNA-sequencing (scRNA-seq) datasets across health and disease to uncover putative targets of SARS-CoV-2 among tissue-resident cell subsets. We identify ACE2 and TMPRSS2 co-expressing cells within lung type II pneumocytes, ileal absorptive enterocytes, and nasal goblet secretory cells. Strikingly, we discovered that ACE2 is a human interferon-stimulated gene (ISG) in vitro using airway epithelial cells and extend our findings to in vivo viral infections. Our data suggest that SARS-CoV-2 could exploit species-specific interferon-driven upregulation of ACE2, a tissue-protective mediator during lung injury, to enhance infection.

IL-5Rα marks nasal polyp IgG4- and IgE-expressing cells in aspirin-exacerbated respiratory disease.

BACKGROUND: The cause of severe nasal polyposis in aspirin-exacerbated respiratory disease (AERD) is unknown. Elevated antibody levels have been associated with disease severity in nasal polyps, but upstream drivers of local antibody production in nasal polyps are undetermined. OBJECTIVE: We sought to identify upstream drivers and phenotypic properties of local antibody-expressing cells in nasal polyps from subjects with AERD. METHODS: Sinus tissue was obtained from subjects with AERD, chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP), CRS without nasal polyps, and controls without CRS. Tissue antibody levels were quantified via ELISA and immunohistochemistry and were correlated with disease severity. Antibody-expressing cells were profiled with single-cell RNA sequencing, flow cytometry, and immunofluorescence, with IL-5Rα function determined through IL-5 stimulation and subsequent RNA sequencing and quantitative PCR. RESULTS: Tissue IgE and IgG4 levels were elevated in AERD compared with in controls (P < .01 for IgE and P < .001 for IgG4 vs CRSwNP). Subjects with AERD whose nasal polyps recurred rapidly had higher IgE levels than did subjects with AERD, with slower regrowth (P = .005). Single-cell RNA sequencing revealed increased IL5RA, IGHG4, and IGHE in antibody-expressing cells from patients with AERD compared with antibody-expressing cells from patients with CRSwNP. There were more IL-5Rα+ plasma cells in the polyp tissue from those with AERD than in polyp tissue from those with CRSwNP (P = .026). IL-5 stimulation of plasma cells in vitro induced changes in a distinct set of transcripts. CONCLUSIONS: Our study identifies an increase in antibody-expressing cells in AERD defined by transcript enrichment of IL5RA and IGHG4 or IGHE, with confirmed surface expression of IL-5Rα and functional IL-5 signaling. Tissue IgE and IgG4 levels are elevated in AERD, and higher IgE levels are associated with faster nasal polyp regrowth. Our findings suggest a role for IL-5Rα+ antibody-expressing cells in facilitating local antibody production and severe nasal polyps in AERD.