Dimethyl itaconate inhibits antigen-specific Th17 cell responses and autoimmune inflammation via modulating NRF2/STAT3 signaling

Pathogenic Th17 cells play a crucial role in autoimmune diseases like uveitis and its animal model, experimental autoimmune uveitis (EAU). Dimethyl itaconate (DMI) possesses potent anti-inflammatory effects. However, there is still a lack of knowledge about the role of DMI in regulating pathogenic Th17 cells and EAU. Here, we reported that intraperitoneal administration of DMI significantly inhibited the severity of EAU via selectively suppressing Th17 cell responses. In vitro antigen stimulation studies revealed that DMI dramatically decreased the frequencies and function of antigen-specific Th17, but not Th1, cells. Moreover, DMI hampered the differentiation of naive CD4+ T cells toward pathogenic Th17 cells. DMI-treated DCs produced less IL-1β, IL-6, and IL-23, and displayed an impaired ability to stimulate antigen-specific Th17 activation. Mechanistically, DMI activated the NRF2/HO-1 pathway and suppressed STAT3 signaling, which subsequently restrains p-STAT3 nuclear translocation, leading to decreased pathogenic Th17 cell responses. Thus, we have identified an important role for DMI in regulating pathogenic Th17 cells, supporting DMI as a promising therapy in Th17 cell-driven autoimmune diseases including uveitis.

Short chain fatty acids inhibit corneal inflammatory responses to TLR ligands via the ocular G-protein coupled receptor 43

PURPOSE

Short chain fatty acids (SCFAs) produced by gut microbiota are known to play primary roles in gut homeostasis by immunomodulation partially through G-protein coupled receptors (GPR) 43. Using mouse models of TLR ligand induced keratitis, we investigated whether SCFAs and GPR43 play any regulatory roles in the pathogenesis of inflammatory responses in the eye.

METHODS

Both human and mouse eyes were labeled with a specific antibody for GPR43 and imaged by a laser scanning confocal microscope. Corneal cups from naïve C57BL/6J (B6) and GPR43 knockout (KO) mice were stimulated with TLR ligands in the presence or absence of sodium butyrate overnight and then processed for RT-PCR assay for expression of GPR43 and cytokines. Keratitis was induced by Poly I:C in wild type (WT) B6, GPR43KO and chimeric mice and the disease severity was evaluated by the corneal fluorescein staining test, and infiltrating cell staining and calculating in corneal whole mount.

RESULTS

GPR43 is expressed in both human and mouse eyes and the expression is bidirectionally regulated by TLR ligands and butyrate. Butyrate significantly inhibited inflammation caused by several TLR ligands such as Poly I:C, Flagellin, and CpG-ODN (TLR-3, 5 and 9 agonists, respectively) in WT, but not GPR43KO, mice. Butyrate inhibition of TLR-induced keratitis is mediated by the GPR43 expressed in tissue but not hematopoietic, cells.

CONCLUSIONS

This is the first report to demonstrate of the protective effect of SCFAs on microbial keratitis, and the dynamic expression and anti-inflammatory function of GPR43 in the eye. SCFAs can modulate inflammation and immunity in the eye through GPR43.

Age effect on the shared etiology of glycemic traits and serum lipids: evidence from a Chinese twin study

PURPOSE

Diabetes and dyslipidemia are among the most common chronic diseases with increasing global disease burdens, and they frequently occur together. The study aimed to investigate differences in the heritability of glycemic traits and serum lipid indicators and differences in overlapping genetic and environmental influences between them across age groups.

METHODS

This study included 1189 twin pairs from the Chinese National Twin Registry and divided them into three groups: aged ≤ 40, 41-50, and > 50 years old. Univariate and bivariate structural equation models (SEMs) were conducted on glycemic indicators and serum lipid indicators, including blood glucose (GLU), glycated hemoglobin A1c (HbA1c), total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C), in the total sample and three age groups.

RESULTS

All phenotypes showed moderate to high heritability (0.37-0.64). The heritability of HbA1c demonstrated a downward trend with age (HbA1c: 0.50-0.79), while others remained relatively stable (GLU: 0.55-0.62, TC: 0.58-0.66, TG: 0.50-0.63, LDL-C: 0.24-0.58, HDL-C: 0.31-0.57). The bivariate SEMs demonstrated that GLU and HbA1c were correlated with each serum lipid indicator (0.10-0.17), except HDL-C. Except for HbA1c and LDL-C, as well as HbA1c and HDL-C, differences in genetic correlations underlying glycemic traits and serum lipids between age groups were observed, with the youngest group showing a significantly higher genetic correlation than the oldest group.

CONCLUSION

Across the whole adulthood, genetic influences were consistently important for GLU, TC, TG, LDL-C and HDL-C, and age may affect the shared genetic influences between glycemic traits and serum lipids. Further studies are needed to elucidate the role of age in the interactions of genes related to glycemic traits and serum lipids.

[Current major public health challenges]

After COVID-19 pandemic, there are still many public health challenges in the world. The double burden of communicable and non-communicable diseases is still heavy in many countries. Mental health and injury are crucial public health problems which are often neglected. Environmental health and food and drug safety are closely related to human health, to which further management and intervention are needed. These problems have different impacts on people at different life stages, resulting in health problems throughout the life course. The current status of public health is far from the requirements set by the Sustainable Development Goals of United Nations or the initiative of "Healthy China 2030". It is necessary for governments and related departments of all countries to consider public health in all policy development to tackle the major challenge to public health.

Red cell distribution in critically ill patients with chronic obstructive pulmonary disease

BACKGROUND

Red blood cell distribution width (RDW) is associated with increased mortality risk in patients with chronic obstructive pulmonary disease (COPD). However, limited data are available for critically ill patients with COPD.

METHODS

Data from the Medical Information Mart for Intensive Care III V1.4 database were analyzed in this retrospective cohort research. The International Classification of Diseases codes were used to identify critically ill patients with COPD. The first value of RDW was extracted within the first 24 h after intensive care unit admission. The endpoint was 28-day all-cause mortality. Multivariable logistic regression analysis was performed to examine the relationship between RDW and 28-day mortality. Age, sex, ethnicity, anemia status, comorbidities, clinical therapy, and disease severity score were considered for subgroup analysis.

RESULTS

A total of 2,344 patients were included with mean (standard deviation) age of 72.3 (11.3) years, in which 1,739 (53.6%) patients were men. The increase in RDW was correlated with an increased risk of 28-day mortality in the multivariate logistic regression model (odds ratio [OR] 1.15; 95% confidence interval [CI] 1.09-1.21). In comparison with the low-RDW group, the middle and high-RDW groups tended to have higher risks of 28-day all-cause mortality (OR [95% CI] 1.03 [0.78-1.34]; OR [95% CI] 1.70 [1.29-2.22]; P trend < 0.0001). Subgroup analyses show no evidence of effect modifications on the correlation of RDW and 28-day all-cause mortality.

CONCLUSION

An increase in RDW was associated with an increased risk of 28-day all-cause mortality in critically ill patients with COPD. Further studies are required to investigate this association.

Fecobionics in proctology: review and perspectives

Fecobionics is a novel integrated technology for assessment of anorectal function. It is a defecatory test with simultaneous measurements of pressures, orientation, and device angle (a proxy of the anorectal angle). Furthermore, the latest Fecobionics prototypes measure diameters (shape) using impedance planimetry during evacuation of the device. The simultaneous measurement of multiple variables in the integrated test allows new metrics to be developed including more advanced novel defecation indices, enabling mechanistic insight in the defecation process at an unprecedented level in patients with anorectal disorders including patients suffering from obstructed defecation, fecal incontinence, and low anterior resection syndrome. The device has the consistency and shape of a normal stool (type 3-4 on the Bristol Stool Form Scale). Fecobionics has been validated on the bench and in animal studies and used in clinical trials to study defecation phenotypes in normal human subjects and patients with obstructed defecation, fecal incontinence, and low anterior resection syndrome after rectal cancer surgery. Subtypes have been defined, especially of patients with obstructed defecation. Furthermore, Fecobionics has been used to monitor biofeedback therapy in patients with fecal incontinence to predict the outcome of the therapy (responder versus non-responder). Most Fecobionics studies showed a closer correlation to symptoms as compared to current technologies for anorectal assessment. The present article outlines previous and ongoing work, and perspectives for future studies in proctology, including in physiological assessment of function, diagnostics, monitoring of therapy, and as a tool for biofeedback therapy.

Mettl3 induced miR-338-3p expression in dendritic cells promotes antigen-specific Th17 cell response via regulation of Dusp16

Pathogenic Th17 cells are critical drivers of multiple autoimmune diseases, including uveitis and its animal model, experimental autoimmune uveitis (EAU). However, how innate immune signals modulate pathogenic Th17 responses remains largely unknown. Here, we showed that miR-338-3p endowed dendritic cells (DCs) with an increased ability to activate interphotoreceptor retinoid-binding protein (IRBP)1-20 -specific Th17 cells by promoting the production of IL-6, IL-1β, and IL-23. In vivo administration of LV-miR-338-infected DCs promoted pathogenic Th17 responses and exacerbated EAU development. Mechanistically, dual-specificity phosphatase 16 (Dusp16) was a molecular target of miR-338-3p. miR-338-3p repressed Dusp16 and therefore strengthened the mitogen-activated protein kinase (MAPK) p38 signaling, resulting in increased production of Th17-polarizing cytokines and subsequent pathogenic Th17 responses. In addition, methyltransferase like 3 (Mettl3), a key m6A methyltransferase, mediated the upregulation of miR-338-3p in activated DCs. Together, our findings identify a vital role for Mettl3/miR-338-3p/Dusp16/p38 signaling in DCs-driven pathogenic Th17 responses and suggest a potential therapeutic avenue for uveitis and other Th17 cell-related autoimmune disorders.

A Phase 0 Study Assessing the Intracranial Activity of a Metabolic Radiosensitizer in Patients with Glioblastoma

PURPOSE/OBJECTIVE(S)

Efforts to overcome treatment resistance in glioblastoma (GBM) have been unsuccessful due to tumor heterogeneity and poor intracranial drug penetration. Targeting altered metabolism is a promising approach to improve GBM therapy despite this heterogeneity. Mycophenolate mofetil (MMF) is an inhibitor of purine synthesis that sensitizes GBM to radiation and temozolomide (TMZ) in vitro and in vivo, but its ability to cross the blood brain barrier and inhibit GBM metabolism in patients is unknown. NCT04477200 is a phase 0/1 dose escalation study of MMF combined with radiation and temozolomide in GBM. Here we report the phase 0 results of this study assessing the intracranial activity of MMF.

MATERIALS/METHODS

Purine (GTP and IMP) and mycophenolic acid (MPA, the active metabolite of MMF) concentrations were determined using mass spectrometry in flash-frozen tumor (enhancing and non-enhancing) and normal cortex obtained from 8 patients with recurrent GBM who received MMF (500, 1000, 1500 and 2000 mg BID, N = 2 patients each dose level) for 1 week prior to re-resection and 5 control patients who did not receive MMF prior to re-resection. Plasma MPA concentration was similarly quantified to calculate the enhancing tumor, non-enhancing tumor and normal cortex to plasma MPA ratios.

RESULTS

Patients who received MMF had a mean MPA concentration of 2.2 ± 0.7 µM in the enhancing tumor samples, 1.2 ± 0.5 µM in the non-enhancing tumor samples and 1.3 ± 0.5 µM in normal cortex. MPA concentration was negligible in control patients. This corresponded to tissue/plasma MPA ratios of 0.31, 0.17 and 0.10 for enhancing tumor, non-enhancing tumor and normal cortex, respectively. The GTP/IMP ratio was decreased by 75% in enhancing tumor in MMF-treated patients compared to untreated controls (p = 0.009), indicating effective target engagement and inhibition of purine synthesis. The GTP/IMP ratio was also decreased in cortex and non-enhancing tumor, though a paucity of control samples prevented statistical analysis.

CONCLUSION

Twice daily MMF treatment yields intracranial drug concentrations above 1 µM and lowers the GTP/IMP ratio in GBMs, consistent with target engagement. As we have previously observed radiosensitization in vitro with MPA concentrations of 1 µM, these data suggest that MMF may achieve adequate CNS penetration for therapeutic benefit. The Phase 1 component of this study to determine the dose limiting toxicity and maximally tolerated dose of MMF when combined with reirradiation in recurrent GBM and radiation and TMZ in newly diagnosed GBM is ongoing.

The Role of Adenosine in γδ T-Cell Regulation of Th17 Responses in Experimental Autoimmune Uveitis

Autoimmune diseases caused by T cells can arise from either T-helper 1 (Th1) or T-helper 17 (Th17)-type pathogenic T cells. However, it is unclear whether these two T-cell subsets are influenced by distinct pathogenic factors and whether treatments that are effective for Th1 responses also work for Th17 responses. To compare these two pathogenic responses, we conducted a systematic analysis in a mouse model of experimental autoimmune uveitis (EAU) to identify the factors that promote or inhibit each response and to determine their responses to various treatments. Our study found that the two types of pathogenic responses differ significantly in their pathological progressions and susceptibility to treatments. Specifically, we observed that extracellular adenosine is a crucial pathogenic molecule involved in the pathogenicity of inflammation and T-cell reactivity and that reciprocal interaction between adenosine and gamma delta (γδ) T cells plays a significant role in amplifying Th17 responses in the development of autoimmune diseases. The potential effect of targeting adenosine or adenosine receptors is analyzed regarding whether such targeting constitutes an effective approach to modulating both γδ T-cell responses and the pathogenic Th17 responses in autoimmune diseases.

Thymosin β4 Alleviates Autoimmune Dacryoadenitis via Suppressing Th17 Cell Response

Purpose

We investigated the therapeutic effect of recombinant thymosin β4 (rTβ4) on rabbit autoimmune dacryoadenitis, an animal model of SS dry eye, and explore its mechanisms.

Methods

Rabbits were treated topically with rTβ4 or PBS solution after disease onset for 28 days, and clinical scores were determined by assessing tear secretion, break-up time, fluorescein, hematoxylin and eosin staining, and periodic acid-Schiff. The expression of inflammatory mediators in the lacrimal glands were measured by real-time PCR. The expression of T helper 17 (Th17) cell-related transcription factors and cytokines were detected by real-time PCR and Western blotting. The molecular mechanism underlying the effects of rTβ4 on Th17 cell responses was investigated by Western blotting.

Results

Topical administration of rTβ4 after disease onset efficiently ameliorated the ocular surface inflammation and relieved the clinical symptoms. Further analysis revealed that rTβ4 treatment significantly inhibited the expression of Th17-related genes (RORC, IL-17A, IL-17F, IL-1R1, IL-23R, and granulocyte-macrophage colony-stimulating factor) and IL-17 protein in lacrimal glands, and meanwhile decreased the inflammatory mediators expression. Mechanistically, we demonstrated that rTβ4 repressed the phosphorylation of signal transducer and activator of transcription 3 (STAT3) both in vivo and in vitro. Activation of the STAT3 signal pathway by Colivelin partly reversed the suppressive effects of rTβ4 on IL-17 expression in vitro.

Conclusions

rTβ4 could alleviate ongoing autoimmune dacryoadenitis in rabbits, probably by suppressing Th17 response via partly affecting the STAT3 pathway. These data may provide a new insight into the therapeutic effect and mechanism of rTβ4 in dry eye associated with Sjögren's syndrome.

Application of combined anterior and posterior approaches for the treatment of cervical tuberculosis with anterior cervical abscess formation and kyphosis using a Jackson operating table: a case report and literature review

BACKGROUND

There have been insufficient reports to date regarding the treatment of cervical spinal tuberculosis, and the optimal surgical approaches to treating this condition have yet to be established.

CASE REPORT

This report describes the treatment of a case of tuberculosis associated with a large abscess and pronounced kyphosis through the use of a combined anterior and posterior approach with the aid of the Jackson operating table. This patient did not exhibit any sensorimotor abnormalities of the upper extremities, lower extremities, or trunk, and presented with symmetrical bilateral hyperreflexia of the knee tendons, while being negative for Hoffmann's sign and Babinski's sign. Laboratory test results revealed an erythrocyte sedimentation rate (ESR) of 42.0 mm/h and a C-reactive protein (CRP) of 47.09 mg/L. Acid-fast staining was negative, and spine magnetic resonance imaging revealed the destruction of the C3-C4 vertebral body and a posterior convex deformity of the cervical spine. The patient reported a visual analog pain score (VAS) of 6, and exhibited an Oswestry disability index (ODI) score of 65. Jackson table-assisted anterior and posterior cervical resection decompression was performed to treat this patient, and at 3 months post-surgery the patient's VAS and ODI scores were respectively reduced to 2 and 17. Computed tomography analyses of the cervical spine at this follow-up time point revealed good structural fusion of the autologous iliac bone graft with internal fixation and improvement of the originally observed cervical kyphosis.

CONCLUSIONS

This case suggests that Jackson table-assisted anterior-posterior lesion removal and bone graft fusion can safely and effectively treat cervical tuberculosis with a large anterior cervical abscess combined with cervical kyphosis, providing a foundation for future efforts to treat spinal tuberculosis.

[Epidemiological characteristics and the establishment and evaluation of a risk prediction model for nosocomial infection in burn patients]

Objective: To find the epidemiological characteristics of nosocomial infection in burn patients, to establish a risk prediction model for nosocomial infection in burn patients based on the screened independent risk factors of the infection, and to analyze its predictive value. Methods: A retrospective case series study was conducted. From May 2016 to December 2019, 3 475 burn patients who were admitted to the Department of Burns of Affiliated Hospital of Jiangnan University met the inclusion criteria, including 2 290 males and 1 185 females, aged from 1 to 94 years. The incidence of nosocomial infection, the detection site and specific composition of pathogenic bacteria were counted. The patients were randomly divided into training group (2 434 cases) and verification group (1 041 cases) in R 4.1.3 statistic software with a ratio of about 7∶3. Factors including gender, age, total burn area, combination of full-thickness burn/inhalation injury/shock/diabetes on admission, admission to intensive care unit (ICU), status of central venous catheterization/endotracheal intubation/urethral catheter indwelling/surgery, nosocomial infection status, days of antibiotic use, and days of hospital stay of patients were compared between the two groups. According to the occurrence of nosocomial infection, the patients were divided into nosocomial infection group (102 cases) and non-nosocomial infection group (3 373 cases), and in addition to the aforementioned data, non-nosocomial infection related data, the season of admission and types of antibiotics used were compared between the two groups. The above-mentioned data were statistically analyzed with one-way analysis of independent sample t test, chi-square test, and Mann-Whitney U test, and the indicators with statistically significant differences between nosocomial infection group and non-nosocomial infection group were included as variables in multivariate logistic regression analysis to screen independent risk factors for the development of nosocomial infection in 3 475 burn patients. On the basis of independent risk factors and important clinical characteristics, a nomogram prediction model was constructed for the risk of developing nosocomial infection of burn patients in training group. In both training group and verification group, receiver operating characteristic (ROC) curves for prediction of nosocomial infection by the prediction model were plotted, and the area under the ROC curve was calculated; calibration curves were plotted to evaluate the conformity between the predicted results of the prediction model and the actual situation; clinical decision curves were plotted to evaluate the clinical utility of the prediction model. Results: The incidence of nosocomial infection of patients included in this study was 2.94% (102/3 475); pathogens were detected from 212 specimens, mainly wound (78 cases, accounting for 36.79%) and blood (64 cases, accounting for 30.19%) specimens; 250 strains of pathogenic bacteria were detected, mainly gram-negative bacteria (153 strains, accounting for 61.20%). All clinical characteristics of patients between training group and verification group were similar (P>0.05). There were statistically significant differences between patients in nosocomial infection group and non-nosocomial infection group in the aspects of age, total burn area, days of antibiotic use, antibiotic use type, days of hospital stay, combination of full-thickness burn, combination of inhalation injury, combination of shock, ICU admission status, central venous catheterization status, endotracheal intubation status, urethral catheter indwelling status, surgery status (with Z values of 4.41, 14.95, 15.70, 650.32, and 13.73, χ2 values of 151.09, 508.30, 771.20, 955.79, 522.67, 967.40, 732.11, and 225.35, respectively, P<0.01). ICU admission, endotracheal intubation, urethral catheter indwelling, and days of hospital stay were independent risk factors for developing nosocomial infection by 3 475 burn patients (with odds ratios of 5.99, 3.39, 9.32, and 6.21, 95% confidence intervals of 2.25-15.99, 1.56-7.39, 2.77-31.31, and 2.48-15.92, respectively, P<0.01). In training group and verification group, the area under ROC curves of the nosocomial infection prediction model based on independent risk factors, total burn area, and central vein catheterization were both 0.97 (with both 95% confidence intervals being 0.95-0.99); the calibration curve analysis showed that the prediction results of the prediction model were in good agreement with the actual situation; the clinical decision curve analysis showed that the prediction model had good clinical utility. Conclusions: The nosocomial infection in burn patients is mainly caused by gram-negative bacteria, with wound as the main infection site, and the independent risk factors including ICU admission, endotracheal intubation, urethral catheter indwelling, and days of hospital stay. Based on independent risk factors and important clinical features, the risk prediction model for nosocomial infection has a good ability to predict nosocomial infection in burn patients.

Upregulated adenosine 2A receptor accelerates post-infectious irritable bowel syndrome by promoting CD4+ T cells’ T helper 17 polarization

BACKGROUND

Post-infectious irritable bowel syndrome (PI-IBS) is generally regarded as a functional disease. Several recent studies have reported the involvement of low-grade inflammation and immunological dysfunction in PI-IBS. T helper 17 (Th17) polarization occurs in IBS. Adenosine and its receptors participate in intestinal inflammation and immune regulation.

AIM

To investigate the role of Th17 polarization of CD4+ T cells regulated by adenosine 2A receptor (A2AR) in PI-IBS.

METHODS

A PI-IBS model was established by infecting mice with Trichinella spiralis. The intestinal A2AR and CD4+ T lymphocytes were detected by immunohistochemistry, and the inflammatory cytokines were detected by enzyme-linked immunoassay. CD4+ T lymphocytes present in the animal’s spleen were separated and cultured with or without A2AR agonist and antagonist. Western blotting and real-time quantitative polymerase chain reaction were performed to determine the effect of A2AR on the cells and intestinal tissue. Cytokine production was determined. The protein and mRNA levels of A2AR associated signaling pathway molecules were also evaluated. Furthermore, A2AR agonist and antagonist were injected into the mouse model and the clinical features were observed.

RESULTS

The PI-IBS mouse model showed increased expression of ATP and A2AR (P < 0.05), and inhibition of A2AR improved the clinical features in PI-IBS, including the abdominal withdrawal reflex and colon transportation test (P < 0.05). The number of intestinal CD4+ T cells and interleukin-17 (IL-17) protein levels increased during PI-IBS, which was reversed by administration of the A2AR antagonist (P < 0.05). CD4+ T cells expressed A2AR and produced IL-17 in vitro, which was regulated by the A2AR agonist and antagonist. The A2AR antagonist increased the production of IL-17 by CD4+ T cells via the Janus kinase-signal transducer and activator of transcription-receptor-related orphan receptor γ signaling pathway.

CONCLUSION

The results of the present study suggested that the upregulation of A2AR increases PI-IBS by promoting the Th17 polarization of CD4+ T cells.

PPAR-α Agonist Fenofibrate Ameliorates Sjögren Syndrome-Like Dacryoadenitis by Modulating Th1/Th17 and Treg Cell Responses in NOD Mice

Purpose

To investigate the effects and mechanisms of fenofibrate, a synthetic ligand of peroxisome proliferator-activated receptor α (PPAR-α), on autoimmune dacryoadenitis in a mouse model of Sjögren syndrome (SS) dry eye.

Methods

Male nonobese diabetic (NOD) mice were fed chow with or without 0.03% fenofibrate for 8 weeks, and clinical scores were determined by assessing tear secretion, fluorescein, and hematoxylin and eosin staining. Intracellular IFN-γ, IL-17, and Foxp3 in CD4+ T cells were measured by flow cytometry. The expressions of Th1, Th17, and Treg cell-related transcription factors and cytokines were detected by real-time PCR. The levels of PPAR-α and liver X receptor β (LXR-β) were detected with real-time PCR and Western blotting.

Results

Fenofibrate efficiently diminished the lymphocytic inflammation in lacrimal glands (LGs), increased tear secretion, and decreased corneal fluorescein staining in NOD mice. Meanwhile, treatment of fenofibrate evidently reduced the proportion of Th1 and Th17 cells and increased the proportion of Treg cells in vivo and vitro, together with decreased expression of T-bet, IFN-γ, RORγt, and IL-17, as well as increased expression of Foxp3 and TGF-β1 in LGs. Furthermore, fenofibrate significantly upregulated the expressions of PPAR-α and LXR-β at the protein and mRNA levels.

Conclusions

Fenofibrate potently attenuated LG inflammation in a model of autoimmune dry eye, and this effect might partially result from regulating Th1/Th17/Treg cell responses by activating PPAR-α/LXR-β signaling. These data suggest that fenofibrate may be a novel class of therapeutic agent for SS-associated dacryoadenitis.

TLR ligand ligation switches adenosine receptor usage of BMDCs leading to augmented Th17 responses in experimental autoimmune uveitis

The extracellular level of adenosine increases greatly during inflammation, which modulates immune responses. We have previously reported that adenosine enhances Th17 responses while it suppresses Th1 responses. This study examined whether response of DC to adenosine contributes to the biased effect of adenosine and determined whether adenosine and TLR ligands have counteractive or synergistic effects on DC function. Our results show that adenosine is actively involved in both in vitro and in vivo activation of pathogenic T cells by DCs; however, under adenosine effect DCs' capability of promoting Th1 versus Th17 responses are dissociated. Moreover, activation of A2ARs on DCs inhibits Th1 responses whereas activation of A2BRs on DC enhances Th17 responses. An intriguing observation was that TLR engagement switches the adenosine receptor from A2ARs to A2BRs usage of bone marrow-derived dendritic cells (BMDCs) and adenosine binding to BMDCs via A2BR converts adenosine's anti-to proinflammatory effect. The dual effects of adenosine and TLR ligand on BMDCs synergistically enhances the Th17 responses whereas the dual effect on Th1 responses is antagonistic. The results imply that Th17 responses will gain dominance when inflammatory environment accumulates both TLR ligands and adenosine and the underlying mechanisms include that TLR ligand exposure has a unique effect switching adenosine receptor usage of DCs from A2ARs to A2BRs, via which Th17 responses are promoted. Our observation should improve our understanding on the balance of Th1 and Th17 responses in the pathogenesis of autoimmune and other related diseases.

Bidirectional Effect of IFN-γ on Th17 Responses in Experimental Autoimmune Uveitis

Pro- and ant-inflammatory effects of IFN-γ have been repeatedly found in various immune responses, including cancer and autoimmune diseases. In a previous study we showed that the timing of treatment determines the effect of adenosine-based immunotherapy. In this study we examined the role of IFN-γ in pathogenic Th17 responses in experimental autoimmune uveitis (EAU). We observed that IFN-γ has a bidirectional effect on Th17 responses, when tested both in vitro and in vivo. Anti-IFN-γ antibody inhibits Th17 responses when applied in the initial phase of the immune response; however, it enhances the Th17 response if administered in a later phase of EAU. In the current study we showed that IFN-γ is an important immunomodulatory molecule in γδ T cell activation, as well as in Th17 responses. These results should advance our understanding of the regulation of Th17 responses in autoimmunity.

The Status of Iodine Nutrition after Removing Iodized Salt in High Water Iodine Regions: a Cross-sectional Study in China

Currently, the removal of iodized salt is carried out in high water iodine regions. The present situation of iodine nutrition and the prevalence of thyroid diseases in such regions have not been clearly elucidated. This study aimed to figure out these problems to help render effective measures for cases of abnormal iodine nutrition status. A cross-sectional study was carried out in four areas of Jining and Heze, Shandong Province, China, with different water iodine concentrations (WIC). In total, 1344 adults were enrolled in this study, and data related to their iodine nutrition, thyroid function, and thyroid ultrasonography were collected. Subjects were grouped according to WIC, urine iodine concentration (UIC), serum iodine concentration (SIC), and combined UIC and SIC for analysis. Iodine levels were in excess in the 100 μg/L ≤ WIC < 300 μg/L and WIC ≥ 300 μg/L areas. Compared with the control WIC group (10-100 μg/L), the WIC ≥ 300 μg/L group had a higher prevalence of thyroid autoimmunity (TAI, 21.25% vs. 13.19%, P <0.05), subclinical hypothyroidism (SH, 20.20% vs. 11.96%, P < 0.05), thyroid nodules (TN, 31.75% vs. 18.71%, P < 0.05), and thyroid dysfunction (23.62% vs. 12.26%, P < 0.05). Compared with the UIC control group (100-300 μg/L), high UIC group (≥ 800 μg/L) had a higher prevalence of TN (33.75% vs. 21.14%, P < 0.05) and thyroid dysfunction (25% vs. 14.47%, P < 0.05). Next, compared with the control SIC group (50-110 μg/L), high SIC group (≥ 110 μg/L) had a higher prevalence of TAI (33.80% vs. 14.47%, P < 0.05), SH (23.94% vs. 14.30%, P < 0.05), and thyroid dysfunction (33.80% vs. 15.29%, P < 0.05). Finally, subjects with the highest UIC and the highest SIC also had a higher prevalence of TAI (25.92% vs. 10.97%, P < 0.05), SH (23.45% vs. 10.97%, P < 0.05), TN (34.56% vs. 15.85%, P < 0.05), and thyroid dysfunction (27.16% vs. 13.41%, P < 0.05) than subjects with middle iodine levels. The iodine nutrition of subjects in the WIC ≥ 300 μg/L areas was still in excess after removing iodized salt from their diets. High levels of iodine also increased the prevalence of TAI, SH, TN, and thyroid dysfunction in those areas. Simply removing iodized salt may not be sufficient for high water iodine regions.

γδ T Cells Activated in Different Inflammatory Environments Are Functionally Distinct

γδ T cells are important immunoregulatory cells in experimental autoimmune uveitis (EAU), and the activation status of γδ T cells determines their disease-enhancing or inhibitory effects. Because γδ T cells can be activated via various pathways, we questioned whether the nature of their activation might impact their function. In this study, we show that γδ T cells activated under different inflammatory conditions differ greatly in their functions. Whereas anti-CD3 treatment activated both IFN-γ⁺ and IL-17⁺ γδ T cells, cytokines preferentially activated IL-17⁺ γδ T cells. γδ T cells continued to express high levels of surface CD73 after exposure to inflammatory cytokines, but they downregulated surface CD73 after exposure to dendritic cells. Although both CD73^high and CD73^low cells have a disease-enhancing effect, the CD73^low γδ T cells are less inhibitory. We also show that polarized activation not only applies to αβ T cells and myeloid cells, but also to γδ T cells. After activation under Th17-polarizing conditions, γδ T cells predominantly expressed IL-17 (gdT17), but after activation under Th1 polarizing conditions (gdT1) they mainly expressed IFN-γ. The pro-Th17 activity of γδ T cells was associated with gdT17, but not gdT1. Our results demonstrate that the functional activity of γδ T cells is strikingly modulated by their activation level, as well as the pathway through which they were activated.

Deep learning based classification of left ventricular function from two-dimensional echocardiographic images

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Philips Healthcare

Background. Echocardiographic quantification of left ventricular function (LVF) is mainly based on ejection fraction (EF) measurements, which relies on either manual or automated identification of endocardial boundaries followed by calculation of model-based end-systolic and end-diastolic LV volumes. Recent developments in artificial intelligence resulted in computer algorithms that allow fully automated detection of endocardial boundaries and measurement of LV volumes and EF. However, this methodology is prone to errors and inter-measurement variability. We hypothesized that a fully automated deep learning algorithm could be developed, which would accurately classify LVF while avoiding volume and EF measurements. This study was designed to test the accuracy of this approach.

Methods. Deep learning algorithm was developed (Philips Research) based on convolutional neural network (CNN) that uses as input dynamic sequences of apical 2- and 4-chamber echocardiographic views obtained without ultrasound enhancing agents. We used for CNN development a database of clinical DICOM studies: a training set of 14,427 studies with normal LV function and 6,135 abnormal, and a validation set of 2,898 normal and 1,081 abnormal studies, based on Philips IntelliSpace Cardiovascular (ISCV) codes found (defined by cardiologists) in the patients’ reports. The CNN was trained to automatically classify LVF into 3 categories: (1) normal, (2) mildly-to-moderately or moderately reduced, and (3) moderately-to-severely or severely reduced. In the validation set, the automated classifications were compared to those in the patients’ reports as a reference standard. Accuracy of the automated classification was tested using contingency tables, from which sensitivity, specificity, and negative and positive predictive values (NPV, PPV) and overall accuracy were calculated for each category of LVF. Additionally, the area under ROC curve (AUC) was calculated to assess the diagnostic accuracy of the automated classification for each LVF category.

Results.  Automated classification of LVF showed high levels of diagnostic accuracy in identifying cases with LVF in all 3 categories, reflected by high AUC values: (1) 0.94, (2) 0.87 and (3) 0.97 (Figure), and overall accuracy of 0.84 (Table). 

Conclusions. Deep learning algorithm based on CNN allowed accurate automated classification of LVF, when tested on ∼4,000 clinical studies and compared to ISCV codes found in the patients’ reports. This novel fully-automated methodology may become a useful aid in the interpretation of echocardiographic images by providing the reader with a preliminary assessment of LVF. Abstract Figure.

TREATMENT OF SECONDARY LOWER LIMB LYMPHEDEMA AFTER GYNECOLOGIC CANCER WITH COMPLEX DECONGESTIVE THERAPY

Secondary lower extremity lymphedema is a common complication of treatment for gynecological cancers. Conservative therapy plays an important role in the treatment of patients with secondary lower extremity lymphedema; in particular, complex decongestive therapy (CDT) has been recognized as an effective nonoperative technique for these patients. But CDT therapy for secondary lower extremity lymphedema remains a problem in China because this technique and its effectiveness have not achieved widespread use and popularity. Our goal was to assess effects of CDT in patients with secondary lower limb lymphedema after treatment for gynecological cancers. The retrospective study consisted of 60 patients who were treated with 20 sessions of CDT. Assessments included objective changes in limb circumference, degree of LE, imaging features, and incidence of erysipelas before and after CDT treatment. We found that CDT can effectively improve lymph stasis and promote backflow, and decrease circumference, interstitial fluid content, and incidence of erysipelas of lymphedematous lower limb. Our results demonstrate that CDT is an effective treatment method for patients with secondary lower limb lymphedema following treatment for gynecologic cancers. This technique should be more widely utilized and popularized in China to improve the quality of life of millions of patients with secondary lower limb lymphedema.

New developments in defecatory studies based on biomechatronics

Introduction

Defecation is a complex process that is difficult to study and analyze directly. In anorectal disease conditions, the defecation process may be disturbed, resulting in symptoms including fecal incontinence and constipation. Current state-of-the-art technology measures various aspects of anorectal function but detailed analysis is impossible because they are stand-alone tests rather than an integrated multi-dimensional test.

Objectives

The need for physiologically-relevant and easy-to-use diagnostic tests for identifying underlying mechanisms is substantial. We aimed to advance the field with integrated technology for anorectal function assessment.

Methods

We developed a simulated stool named Fecobionics that integrates several tests to assess defecation pressures, dimensions, shape, orientation and bending during evacuation. A novelty is that pressures are measured in axial direction, i.e. in the direction of the trajectory. Using this novel tool, we present new analytical methods to calculate physiologically relevant parameters during expulsion in normal human subjects.

Results

Data are reported from 28 human subjects with progressively more advanced versions of Fecobionics. A new concept utilizes the rear-front pressure (preload-afterload) diagram for computation of novel defecation indices. Fecobionics obtained physiological data that cannot be obtained with current state-of-the-art technologies.

Conclusion

Fecobionics measures well known parameters such as expulsion time and pressures as well as new metrics including defecation indices. The study suggests that Fecobionics is effective in evaluation of key defecatory parameters and well positioned as an integrated technology for assessment of anorectal function and dysfunction.

Role of miR-27a in the regulation of cellular function via the inhibition of MAP2K4 in patients with asthma

Asthma is a respiratory disease with a clinically high incidence, and repeated attacks of asthma severely affect the quality of life and even pose a threat to health, leading to severe burdens on families and even the society. A thorough understanding of the pathogenesis of asthma is essential for the prevention and treatment of asthma. This study aimed to examine the effect of the microRNA miR-27a on asthma and its relationship with mitogen activated protein kinase 4 (MAP2K4). Patients with asthma admitted to our hospital from August 2016 to August 2018 and healthy participants in the same period were included in this prospective analysis. The mRNA expression levels of miR-27a and MAP2K4 in peripheral blood were determined. Airway smooth muscle cells (ASMCs) were used to study the effects of miR-27a and MAP2K4 on cell biological behavior. The relationship between miR-27a and MAP2K4 was verified using dual-luciferase reporter assay. miR-27a expression was increased and MAP2K4 mRNA expression was decreased in asthma (P < 0.05). Increasing miR-27a expression and inhibiting MAP2K4 expression could enhance the activity of ASMCs, whereas inhibiting miR-27a expression and increasing MAP2K4 expression had the opposite effect (P < 0.05). Dual-luciferase reporter assay results showed that the fluorescence activity of MAP2K4-wild type was inhibited by increased miR-27a expression (P < 0.05). miR-27a promotes the proliferation and invasion of ASMCs by targeting MAP2K4 and is involved in the occurrence of asthma.

Adenosine receptor ligation tips the uveitogenic Th1 and Th17 balance towards the latter in experimental autoimmune uveitis-induced mouse

Various pathological conditions are accompanied by release of adenosine triphosphate (ATP) from the intracellular to the extracellular compartment, where it degrades into adenosine and modulates immune responses. Previous studies concluded that both ATP and its degradation product adenosine are important immune-regulatory molecules; ATP acted as a danger signal that promotes immune responses, but adenosine's effect was inhibitory. We show that adenosine receptor ligation plays an important role in balancing Th1 and Th17 pathogenic T cell responses in experimental autoimmune uveitis (EAU). While its effect on Th1 responses is inhibitory, its effect on Th17 responses is enhancing, thereby impacting the balance between Th1 and Th17 responses. Mechanistic studies showed that this effect is mediated via several immune cells, among which γδ T cell activation and dendritic cell differentiation are prominent; adenosine- and γδ-mediated immunoregulation synergistically impact each other's effect. Adenosine receptor ligation augments the activation of γδ T cells, which is an important promoter for Th17 responses and has a strong effect on dendritic cell (DC) differentiation, tipping the balance from generation of DCs that stimulate Th1 responses to those that stimulate Th17 responses. The knowledge acquired in this study should improve our understanding of the immune-regulatory effect of extracellular ATP-adenosine metabolism and improve treatment for autoimmune diseases caused by both Th1-and Th17-type pathogenic T cells.

Vaccination with circulating exosomes in autoimmune uveitis prevents recurrent intraocular inflammation

BACKGROUND

Exosomes participate in intercellular communication and act as important molecular vehicles in the regulation of numerous physiological and pathological processes, including autoimmune development. The role of circulating exosomes in the development of autoimmune uveitis is unknown. In this study, using the rat model of experimental autoimmune uveitis, which has clinical and histological features of pan uveitis in man, we evaluated the immunoregulatory function of circulating exosomes.

METHODS

Experimental autoimmune uveitis was induced in Lewis rats either immunised with interphotoreceptor retinoid-binding protein R16 peptides or injected with activated R16-specific T cells. The disease incidence and severity were examined by indirect fundoscopy and flow cytometry. Circulating exosomes were isolated from peripheral blood of naïve and Day 14 R16 immunised Lewis rats. The effect of exosomes on specific T cells was evaluated by R16-specific T cell proliferation, cytokine production and recurrent uveitis induction.

RESULTS

Circulating exosomes derived from active immunised uveitis rats selectively inhibited immune responses of R16-specific T cells in vitro. Vaccination of naïve rats with these exosomes reduced the incidence of recurrent uveitis in an antigen-specific manner. Antigen-specific uveitogenic T cells reduced IFN-γ production and increased IL-10 after vaccination.

CONCLUSIONS

Circulating exosomes in autoimmune uveitis have the potential to be a novel treatment for recurrent autoimmune uveitis.

Enhanced Blocking Effect: A New Strategy to Improve the NO2 Sensing Performance of Ti3C2Tx by γ-Poly(l-glutamic acid) Modification

Titanium carbide (Ti₃C₂T_x) with a distinctive structure, abundant surface chemical groups, and good electrical conductivity has shown great potential in fabricating superior gas sensors, but several challenges, such as low response kinetics, poor reversibility, and serious baseline drift, still remain. In this work, γ-poly(l-glutamic acid) (γ-PGA) with a blocking effect is exploited to modify Ti₃C₂T_x, thereby stimulating the positive response behavior of Ti₃C₂T_x and improving its gas sensing performance. On account of the unique synergetic interaction between Ti₃C₂T_x and γ-PGA, the response of the flexible Ti₃C₂T_x/γ-PGA gas sensor to 50 ppm NO₂has been improved to a large extent (average 1127.3%), which is 85 times that of Ti₃C₂T_x (only 13.2%). Moreover, the as-fabricated Ti₃C₂T_x/γ-PGA sensor not only exhibits a shorter response/recovery time (average 43.4/3 s) compared with the Ti₃C₂T_x-based sensor (∼18.5/18.3 min) but also shows good reversibility and repeatability (relative standard deviation (RSD) <1%) at room temperature within 50% relative humidity (RH). The improved gas sensing properties of the Ti₃C₂T_x/γ-PGA sensor can be attributed to the enhancement of effective adsorption and the blocking effect assisted by water molecules. Furthermore, the gas sensing response of the Ti₃C₂T_x/γ-PGA sensor is studied at different RHs, and humidity compensation of the sensor is carried out using the multiple regression method. This work demonstrates a novel strategy to enhance the gas sensing properties of Ti₃C₂T_x by γ-PGA modification and provides a new way to realize highly responsive gas detection at room temperature.

Optimization of the electron beam dump for a GeV-class laser electron accelerator

The advances of laser-driven electron acceleration offer the promise of great reductions in the size of high-energy electron accelerator facilities. Accordingly, it is desirable to design compact radiation shielding for such facilities. A key component of radiation shielding is the high-energy electron beam dump. In an effort to optimize the electron beam dump design, different material combinations have been simulated with the FLUKA Monte Carlo code in the range of 1-40 GeV. The studied beam dump configurations consist of alternating layers of high-Z material (lead or iron) and low-Z material (high-density concrete or borated polyethylene) in either three-layer or five-layer structures. The designs of various beam dump configuration have been compared and it has been found that the iron and concrete stacking in a three-layer structure with a thick iron layer results in the lowest dose at 1, 10, and 40 GeV. The performance of the beam dump exhibits a strong dependence on the selected materials, the stacking method, the beam dump thickness, as well as the electron energy. This parametric study provides general insights that can be used for compact shielding design of future electron accelerator facilities.

[Early infantile epileptic encephalopathy caused by PACS2 gene variation: three cases report and literature review]

Objective: To explore the clinical features of three early-onset infantile epileptic encephalopathy (EIEE) patients with variations in phosphofurin acidic cluster sorting protein 2 (PACS2) gene and to review related literature. Methods: The clinical data and genetic features of three early infantile epileptic encephalopathy 66 (EIEE66) patients with a PACS2 gene variant diagnosed by the Department of Neurology, Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science and Technology, from January 2019 to January 2020 were retrospectively analyzed. A literature search with "PACS2 gene" "PACS2" "epileptic encephalopathy, early infantile, 66" and"early infantile epileptic encephalopathy 66" as key words was conducted at PubMed, China National Knowledge Infrastructure (CNKI), and Wanfang Data Knowledge Service Platform (up to July 2020). Case reports of patients with PACS2 gene variants and related clinical data were chosen and reviewed. Results: Case 1, a girl aged 2 years and 2 months was hospitalized because of repetitive seizures within more than two years and 6 convulsions within 2 days due to fever. The seizures occurred at the age of 7 days, characterized by focal seizures and generalized tonic-clonic seizures. Sometimes, the frequency of seizures increased with high fever. Regular treatment had not been implemented in the early stage, later seizures were controlled by valproic acid treatment. Case 2, a female 5 months of age, was admitted due to recurrent convulsions in nearly five months. Focal seizures occured at the age of 5 days. And the brain magnetic resonance imaging (MRI) confirmed abnormal cerebellar hemispheres and cerebellar vermis, as well as cerebellar dysplasia. Several antiepileptic drugs and ketogenic diet were ineffective in the early months, and later seizures were controlled with the treatment with levetiracetam and valproic acid. Case 3, a five-month-old girl, was admitted because of recurrent convulsions for nearly five months. At the age of 3 days, she had tonic seizures, and showed good response to levetiracetam and valproic acid. All the three cases were accompanied by development delay and dysmorphic facial appearance, and got seizure-free with the treatment with valproic acid. All copy-number variant analysis and trio whole exome sequencing revealed a recurrent heterozygous missense variant (c.625G>A) in PACS2 gene. No related reports were found in Chinese journals, while 4 reports were found in English literature, describing 17 patients in total. With these 3 patients included, 20 cases had only two missense PACS2 gene variants, in whom 19 cases carried the variant c. 625G>A (p.Glu209Lys) and 1 case carried the variant c. 631G>A (p.Glu211Lys). Epilepsy was the first reported symptom in all patients, and 17 cases had seizures during the first week of life. Out of the various seizure types observed, focal seizures were the predominant types (13 cases), whereas tonic, clonic, tonic-clonic seizures and non-motor seizures (such as facial flushing) were also reported. Almost all patients showed facial dysmorphism and developmental delay to different degrees. Total of 16 patients had abnormal brain MRI recordings, and 13 cases had cerebellar hypoplasia. More specifically, 7 cases showed inferior vermian hypoplasia, and 3 cases showed hypothalamic fusion anomaly. The treatment was mainly aimed to control the symptoms. And the recommended effective treatment for epilepsy has not been reported yet. Conclusions: PACS2-related early infantile epileptic encephalopathy is an autosomal dominant disease, characterized by seizure onset within the first week of life in most cases, dysmorphic facial appearance, and various degrees of developmental retardation. Treatment with valproic acid showed good effect.

Novel bionics developments in gastroenterology: fecobionics assessment of lower GI tract function

Biomechatronics (bionics) is an applied science that is interdisciplinary between biology and engineering (mechanical, electrical and electronics engineering). Biomechatronics covers a wide area and is probably best known in development of prosthetic limbs, vision aids, robotics and neuroscience. Although the gastrointestinal tract is difficult to study, it is particularly suited for a bionics approach as demonstrated by recent developments. Ingestible capsules that travel the tract and record physiological variables have been used in the clinic. Other examples include sacral nerve stimulators that seek to restore normal anorectal function. Recently, we developed a simulated stool termed fecobionics. It has the shape of normal stool and records a variety of parameters including pressures, bending (anorectal angle) and shape changes during colonic transit and defecation, i.e. it integrates several current tests. Fecobionics has been used to study defecation patterns in large animals as well as in humans (normal subjects and patient groups including patients with symptoms of obstructed defecation and fecal incontinence). Recently, it was applied in a canine colon model where it revealed patterns consistent with shallow waves originating from slow waves generated by the interstitial cells of Cajal. Furthermore, novel analysis such as the rear-front pressure (preload-afterload) diagram and quantification of defecation indices have been developed that enable mechanistic insight. This paper reviews the fecobionics technology and outlines perspectives for future applications.

Timing Effect of Adenosine-Directed Immunomodulation on Mouse Experimental Autoimmune Uveitis

Adenosine is an important regulatory molecule of the immune response. We have previously reported that treatment of experimental autoimmune uveitis (EAU)-prone mice with an adenosine-degrading enzyme (adenosine deaminase) prohibited EAU development by inhibiting Th17 pathogenic T cell responses. To further validate that the targeting of adenosine or adenosine receptors effectively modulates Th17 responses, we investigated the effect of adenosine receptor antagonists. In this study, we show that the A2AR antagonist SCH 58261 (SCH) effectively modulates aberrant Th17 responses in induced EAU. However, timing of the treatment is important. Whereas SCH inhibits EAU when administered during the active disease stage, it did not do so if administered during quiescent disease stages, thus implying that the existing immune status influences the therapeutic effect. Mechanistic studies showed that inhibition of γδ T cell activation is crucially involved in adenosine-based treatment. Adenosine is an important costimulator of γδ T cell activation, which is essential for promoting Th17 responses. During ongoing disease stages, adenosine synergizes with existing high levels of cytokines, leading to augmented γδ T cell activation and Th17 responses, but in quiescent disease stages, when existing cytokine levels are low, adenosine does not enhance γδ T cell activation. Our results demonstrated that blockade of the synergistic effect between adenosine and inflammatory cytokines at active disease stages can ameliorate high-degree γδ T cell activation and, thus, suppress Th17 pathogenic T cell responses.

Genome-wide analysis in 756,646 individuals provides first genetic evidence that ACE2 expression influences COVID-19 risk and yields genetic risk scores predictive of severe disease

SARS-CoV-2 enters host cells by binding angiotensin-converting enzyme 2 (ACE2). Through a genome-wide association study, we show that a rare variant (MAF = 0.3%, odds ratio 0.60, P=4.5×10^-13) that down-regulates ACE2 expression reduces risk of COVID-19 disease, providing human genetics support for the hypothesis that ACE2 levels influence COVID-19 risk. Further, we show that common genetic variants define a risk score that predicts severe disease among COVID-19 cases.

Augmented Th17-stimulating activity of BMDCs as a result of reciprocal interaction between γδ and dendritic cells

Our previous studies demonstrated that γδ T cells have a strong regulatory effect on Th17 autoimmune responses in experimental autoimmune uveitis (EAU). In the current study, we show that reciprocal interactions between mouse γδ T cells and dendritic cells (DCs) played a major role in γδ regulation of Th17 responses. Mouse bone marrow-derived dendritic cells (BMDCs) acquired an increased ability to enhance Th17 autoimmune responses after exposure to γδ T cells; meanwhile, after exposure, a significant portion of the BMDCs expressed CD73 - a molecule that is fundamental in the conversion of immunostimulatory ATP into immunosuppressive adenosine. Functional studies showed that CD73+ BMDCs were uniquely effective in stimulating the Th17 responses, as compared to CD73- BMDCs; and activated γδ T cells are much more effective than non-activated γδ T cells at inducing CD73+ BMDCs. As a result, activated γδ T cells acquired greater Th17-enhancing activity. Treatment of BMDCs with the CD73-specific antagonist APCP abolished the enhancing effect of the BMDCs. γδ T cells more effectively induced CD73+ BMDCs from the BMDCs that were pre-exposed to TLR ligands, and the response was further augmented by adenosine. Moreover, BMDCs acquired increased ability to stimulate γδ activation after pre-exposure to TLR ligands and adenosine. Our results demonstrated that both extra-cellular adenosine and TLR ligands are critical factors in augmented Th17 responses in this autoimmune disease, and the reciprocal interactions between γδ T cells and DCs play a major role in promoting Th17 responses.

A multiscale modelling approach to elucidate the mechanism of the oxygen evolution reaction at the hematite-water interface

Photoelectrochemical (PEC) splitting of water to make hydrogen is a promising clean-energy technology. The oxygen evolution reaction (OER) largely determines the energy efficiency in PEC water-splitting. Hematite, which is a cheap and sustainable semiconductor material with excellent chemical properties, a favourable band gap (2.1 eV) and composed of earth abundant elements is a suitable model photoanode material for studying OER. To understand the design of energy efficient anodes, it is highly desirable to have mechanistic insight into OER at an atomistic level which can be directly connected to experimentally measured quantities. We present a multiscale computational model of OER which connects the thermodynamics and kinetics of elementary charge transfer reactions in OER to kinetics of OER at laboratory length and time scales. We couple density functional theory (DFT) and DFT based molecular dynamics (DFT-MD) simulations with solvent effects at an atomistic level with kinetic Monte Carlo (kMC) simulations at a coarse-grained level in our multiscale model. The time and applied bias potential dependent surface coverage, which are experimentally not known, and the O₂ evolution rate during OER at the hematite-water interface are calculated by the multiscale model. Furthermore, the multiscale model demonstrates the effect of explicitly modelling the interaction of water with the electrode surface via direct adsorption.

Long non-coding RNA MIR4435-2HG recruits miR-802 from FLOT2 to promote melanoma progression

OBJECTIVE

The regulatory mechanism of lncRNA MIR4435-2HG has been extensively investigated in human cancers other than melanoma. This study aims to elucidate the role of lncRNA MIR4435-2HG in melanoma.

MATERIAL AND METHODS

The mRNA expression was detected by RT-qPCR. MTT assay, Transwell assay and Dual-Luciferase reporter assay were used to investigate the regulatory mechanism of lncRNA MIR4435-2HG.

RESULTS

Upregulation of lncRNA MIR4435-2HG was identified in melanoma and promoted melanoma cell proliferation, migration and invasion. In addition, lncRNA MIR4435-2HG serves as the ceRNA of miR-802. MiR-802 inhibited melanoma progression by downregulating lncRNA MIR4435-2HG. Besides, miR-802 directly targets FLOT2. And knockdown of FLOT2 restrained the progression of melanoma by downregulating lncRNA MIR4435-2HG and upregulating miR-802.

CONCLUSIONS

LncRNA MIR4435-2HG promotes cell proliferation, migration and invasion in melanoma by sponging miR-802 and upregulating FLOT2.

A catalog of associations between rare coding variants and COVID-19 outcomes

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes coronavirus disease-19 (COVID-19), a respiratory illness that can result in hospitalization or death. We investigated associations between rare genetic variants and seven COVID-19 outcomes in 543,213 individuals, including 8,248 with COVID-19. After accounting for multiple testing, we did not identify any clear associations with rare variants either exome-wide or when specifically focusing on (i) 14 interferon pathway genes in which rare deleterious variants have been reported in severe COVID-19 patients; (ii) 167 genes located in COVID-19 GWAS risk loci; or (iii) 32 additional genes of immunologic relevance and/or therapeutic potential. Our analyses indicate there are no significant associations with rare protein-coding variants with detectable effect sizes at our current sample sizes. Analyses will be updated as additional data become available, with results publicly browsable at https://rgc-covid19.regeneron.com.

Short chain fatty acids inhibit endotoxin-induced uveitis and inflammatory responses of retinal astrocytes

Short chain fatty acids (SCFAs) are produced by gut microbiota as fermentation products of digestion-resistant oligosaccharides and fibers. Their primary roles are functioning as major energy sources for colon cells and assisting in gut homeostasis by immunomodulation. Recent evidence suggests that they affect various organs both at cellular and molecular levels, and regulate functions in distance sites including gene expression, cell proliferation, cell differentiation, apoptosis and inflammation. In this study, we examined whether SCFAs are present in the mouse eye and whether SCFAs affect inflammatory responses of the eye and retinal astrocytes (RACs). We observed that intra-peritoneal injected SCFAs were detected in the eye and reduced intraocular inflammation induced by lipopolysaccharide (LPS). Moreover, SCFAs displayed two disparate effects on LPS-stimulated RACs - namely, cytokine and chemokine production was reduced, but the ability to activate T cells was enhanced. Our results support the existence of gut-eye cross talk and suggest that SCFAs can cross the blood-eye-barrier via the systemic circulation. If applied at high concentrations, SCFAs may reduce inflammation and impact cellular functions in the intraocular milieu.

Identification of non-Hodgkin lymphoma patients at risk for treatment-related vertebral density loss and fractures

Information on bone loss in treated non-Hodgkin's lymphoma patients is limited. In this study, we used CT to analyze bone loss as well as prevalent and incident fractures. We found severe bone loss, a high rate of fractures, and a novel association between bone loss and the international prognostic index.

INTRODUCTION

To investigate bone loss and fracture risk in non-Hodgkin-lymphoma (NHL) patients by (i) comparing treatment-related vertebral density (VD) loss in NHL patients with control subjects and (ii) investigating associations of VD loss versus fracture risk. Further, associations of VD loss and clinical parameters were investigated.

METHODS

VD of 123 NHL patients was measured pre- and post-treatment in the L1, L2, and L3 vertebrae in routine computed tomography (CT) scans, performed between Jan 2016 and Mar 2017. Control measurements (n = 52) were obtained from CT colonographies between Sept 2003 and Sept 2017 and their subsequent follow-up-exams (10-137 months). Prevalent and incident (between baseline and follow-up) fractures were assessed in all subjects, and VD loss per year was calculated. Linear regression models were used to (i) compare VD loss between patients and controls and (ii) identify associations between VD loss and clinical parameters. Using logistic regression models, ORs for fractures per SD change in VD were assessed in patients. Analyses were adjusted for age, sex, and contrast application.

RESULTS

NHL patients experienced significantly greater VD_L1-3 loss than controls (P = 0.003), and greater VD_L1-3 loss was associated with a greater likelihood of incident fractures (OR, [95%-CI], P 1.90, [1.03, 3.51], 0.04). Patients with an initial international prognostic index (IPI) of 5 suffered significantly greater VD loss compared with an IPI of 0 (P = 0.01).

CONCLUSION

Using VD measurements in routine CT scans, substantial vertebral bone loss in NHL patients could be documented with a high incidence of fractures.

Treatment of secondary lower limb lymphedema after gynecologic cancer with complex decongestive therapy

Secondary lower extremity lymphedema is a common complication of treatment for gynecological cancers. Conservative therapy plays an important role in the treatment of patients with secondary lower extremity lymphedema; in particular, complex decongestive therapy (CDT) has been recognized as an effective nonoperative technique for these patients. But CDT therapy for secondary lower extremity lymphedema remains a problem in China because this technique and its effectiveness have not achieved widespread use and popularity. Our goal was to assess effects of CDT in patients with secondary lower limb lymphedema after treatment for gynecological cancers. The retrospective study consisted of 60 patients who were treated with 20 sessions of CDT. Assessments included objective changes in limb circumference, degree of LE, imaging features, and incidence of erysipelas before and after CDT treatment. We found that CDT can effectively improve lymph stasis and promote backflow, and decrease circumference, interstitial fluid content, and incidence of erysipelas of lymphedematous lower limb. Our results demonstrate that CDT is an effective treatment method for patients with secondary lower limb lymphedema following treatment for gynecologic cancers. This technique should be more widely utilized and popularized in China to improve the quality of life of millions of patients with secondary lower limb lymphedema.

[shRNA-Mediated Suppression of γ-Synuclein Leading to Downregulation of p38/ERK/JNK Phosphorylation and Cell Cycle Arrest in Endometrial Cancer Cells]

In this study, we explored the effects of treating human endometrial cancer cells with γ-synuclein-specific short hairpin RNA (shRNA) and elucidated the associated mechanisms in vitro and in vivo through the p38, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK) signaling pathways. Cell proliferation and migration were assessed using CCK8, Transwell, and scratch wound healing assays. Flow cytometry and laser scanning confocal microscopy were used to detect cell cycle changes. Relative levels of phosphorylated and non-phosphorylated (p) p38, ERK1/2 and JNK1/2/3 were determined in vitro and in vivo using simple western blotting assays. Cell proliferation in the experimental group decreased significantly and cells transfected with shRNA showed reduced migration rates (P < 0.05). p-p38, p-ERK1/2, and p-JNK1/2/3 levels were downregulated in the experimental group in vitro and in vivo. Tumor volumes and weights in the experimental group were significantly lower (P < 0.05). Tumor formation time in the negative control group was significantly shorter (P < 0.05). Flow cytometry showed that the number of cells in the G1 and mitotic phases increased and that in the S phase decreased after SNCG silencing (P < 0.05). Confocal microscopy showed that the percentage of cells in the mitotic phase increased after SNCG gene silencing (P < 0.05). We conclude that shRNA-mediated suppression of γ-synuclein decreased the proliferation, migration, and tumorigenicity of endometrial cancer cells via downregulation of p38, ERK, and JNK phosphorylation. High SNCG expression is closely related to the growth cycle of endometrial cancer cells.