S100a10 deficiency in neutrophils aggravates ulcerative colitis in mice

BACKGROUND AND AIMS

S100a10 is a member of the S100 family of proteins, which plays a key role in the depression and tumor metastasis. However, the role of S100a10 is unclear in ulcerative colitis.

METHODS

The effect of S100a10 was assessed using a murine ulcerative colitis model which was accompanied by parameters including body weight loss, disease activity index, histological score, colon weight and length. The quantity and role of immune cells was determined by flow cytometry and bone marrow chimeric mice. Neutrophils depletion, adoptive cell transfer and conditional knockout mice were used to ascertain which cells played the key role in ulcerative colitis. The function of neutrophils was evaluated by migration assay, phagocytosis assay, multiplex immunoassay and real-time PCR.

RESULTS

In this study, our data showed that S100a10-/- mice were prone to ulcerative colitis induced by dextran sodium sulfate. Neutrophils number increased in colon of S100a10-/- mice after dextran sodium sulfate treatment significantly. Meanwhile, adoptive transfer of neutrophils from wild type mice partially decreased the susceptibility of S100a10-/- mice to dextran sodium sulfate. There was no difference in ulcerative colitis between the groups of S100a10-/- mice without neutrophils and wild type mice. Finally, we found that S100a10-/- neutrophils had stronger function in secretion and synthesis of inflammatory factor.

CONCLUSIONS

In one word, these results suggest that S100a10 has a role in inhibiting the pathogenesis of ulcerative colitis through regulation of neutrophils function.

Epithelial TIPE1 Protein Guards against Colitis by Inhibiting TNF-α-Mediated Inflammation

Intestinal epithelial cells (IECs) at the internal/external interface orchestrate the mucosal immune response, and IEC dysfunction has been linked to multiple inflammatory diseases, including inflammatory bowel disease. In this study, we found that a member of the TNF-α-induced protein 8 (TNFAIP8 or TIPE) family called TIPE1 is indispensable for maintaining epithelial cell barrier integrity and homeostasis under inflammatory conditions. TIPE1-deficient mice, or chimeric mice that were deficient in TIPE1 in their nonhematopoietic cells, were more sensitive to dextran sulfate sodium-induced experimental colitis; however, TIPE1 deficiency had no impact on the development of inflammation-associated and sporadic colorectal cancers. Mechanistically, TIPE1 prevented experimental colitis through modulation of TNF-α-dependent inflammatory response in IECs. Importantly, genetic deletion of both TIPE1 and its related protein TNFAIP8 in mice led to the development of spontaneous chronic colitis, indicating that both of these two TIPE family members play crucial roles in maintaining intestinal homeostasis. Collectively, our findings highlight an important mechanism by which TIPE family proteins maintain intestinal homeostasis and prevent inflammatory disorders in the gut.

Myeloid-restricted CD68 deficiency attenuates atherosclerosis via inhibition of ROS-MAPK-apoptosis axis

In atherosclerosis, macrophages derived from blood monocytes contribute to non-resolving inflammation, which subsequently primes necrotic core formation, and ultimately triggers acute thrombotic vascular disease. Nevertheless, little is known about how inflammatory cells, especially the macrophages fuel atherosclerosis. CD68, a unique class D scavenger receptor (SRD) family member, is specifically expressed in monocytes/macrophages and remarkably up-regulated upon oxidized low-density lipoprotein (ox-LDL) stimulation. Nonetheless, whether and how myeloid-specific CD68 affects atherosclerosis remains to be defined. To determine the essential in vivo role and mechanism linking CD68 to atherosclerosis, we engineered global and myeloid-specific CD68-deficient mice on an ApoE background. On Western diet, both the mice with global and the myeloid-restricted deletion of CD68 on ApoE background attenuated atherosclerosis, accompanied by diminished immune/inflammatory cell burden and necrotic core content, but increased smooth muscle cell content in atherosclerotic plaques. In vitro experiments revealed that CD68 deficiency in macrophages resulted in attenuated ox-LDL-induced macrophage apoptosis. Additionally, CD68 deficiency suppressed ROS production, while removal of ROS can markedly reversed this effect. We further showed that CD68 deficiency affected apoptosis through inactivation of the mitogen-activated protein kinase (MAPK) pathway. Our findings establish CD68 as a macrophage lineage-specific regulator of "ROS-MAPK-apoptosis" axis, thus providing a previously unknown mechanism for the prominence of CD68 as a risk factor for coronary artery disease. Its therapeutic inhibition may provide a potent lever to alleviate the cardiovascular disease.

Analysis of the Safety and Pregnancy Outcomes of Fertility-sparing Surgery in Ovarian Malignant Sex Cord-stromal Tumours: A Multicentre Retrospective Study

AIMS

To assess the difference in survival between fertility-sparing surgery (FSS) and radical surgery and explore pregnancy outcomes after FSS in stage I malignant sex cord-stromal tumours (MSCSTs).

MATERIALS AND METHODS

We carried out a multicentre retrospective cohort study on patients who were diagnosed with MSCSTs and the tumour was confined to one ovary. The patients were divided into FSS and radical surgery groups. Inverse probability of treatment weighting (IPTW) was used to balance variables between the two groups. Kaplan-Meier analysis was used to compare the difference in disease-free survival (DFS). Univariate and multivariate Cox regression analysis was used to find risk factors of DFS. Univariate logistic regression analysis was used to assess risk factors of pregnancy.

RESULTS

In total, 107 patients were included, of whom 54 (50.5%) women underwent FSS and 53 (49.5%) received radical surgery. After IPTW, a pseudo-population of 208 was determined and all of the covariates were well balanced. After a median follow-up time of 50 months (range 7-156 months), 10 patients experienced recurrence and two died. There was no significant difference in DFS between the two groups, both in unweighted (P = 0.969) or weighted cohorts (P = 0.792). In the weighted cohort, stage IC (P = 0.014), tumour diameter >8 cm (P = 0.003), incomplete staging surgery (P = 0.003) and no adjuvant chemotherapy (P < 0.001) were the four high-risk factors associated with a shorter DFS. Among 14 patients who had pregnancy desire, 11 (78.6%) women conceived successfully; the live birth rate was 76.9%. In univariate analysis, only adjuvant chemotherapy (P = 0.009) was associated with infertility.

CONCLUSIONS

On the premise of complete staging surgery, FSS is safe and feasible in early stage MSCSTs with satisfactory reproductive outcomes.

TIPE1 inhibits osteosarcoma tumorigenesis and progression by regulating PRMT1 mediated STAT3 arginine methylation

Osteosarcoma (OS), the most common primary malignancy of the bone, has a poor prognosis due to its high mortality rate and high potential for metastasis. Thus, it is urgently necessary to explore functional molecular targets of therapeutic strategies for osteosarcoma. Here, we reported that TIPE1 expression was decreased in osteosarcoma tissues compared to normal and adjacent nontumor tissues, and its expression was negatively related to tumor stage and tumor size. Functional assays showed that TIPE1 inhibited osteosarcoma carcinogenesis and metastatic potential both in vivo and in vitro. Furthermore, we investigated that the STAT3 signaling pathway was significantly downregulated after TIPE1 overexpression. Mechanistically, TIPE1 bind to the catalytic domain of PRMT1, which deposits an asymmetric dimethylarginine (ADMA) mark on histone/non-histone proteins, and thus inhibited PRMT1 mediated STAT3 methylation at arginine (R) residue 688. This abolished modification decreased STAT3 transactivation and expression, by which subsequently suppressed osteosarcoma malignancy. Taken together, these data showed that TIPE1 inhibits the malignant transformation of osteosarcoma through PRMT1-mediated STAT3 arginine methylation and ultimately decreases the development and metastasis of osteosarcoma. TIPE1 might be a potential molecular therapeutic target and an early biomarker for osteosarcoma diagnosis.

[Early warning of low maternal unconjugated estriol level by prenatal screening for fetus with X-linked ichthyosis]

Objective: To analyze the characteristic of prenatal serological screening in fetus with X-linked ichthyosis (XLI), and to explore the relationship between unconjugated estriol (uE₃) levels and XLI. Methods: A total of 56 fetuses with Xp22.31 microdeletion indicated by prenatal diagnosis and 70 fetuses diagnosed with trisomy 21 and 26 fetuses with trisomy 18 in Henan Provincial People's Hospital and Affiliated Hospital of Weifang Medical College from September 2016 to June 2021 were collected. The multiples of median (MoM) values of uE₃, alpha-fetoprotein (AFP), and human chorionic gonadotropin (hCG) during the second trimester of pregnancy were retrospectively analyzed. Prenatal diagnosis was made by amniotic fluid karyotype analysis and genome copy number variant analysis, parent genetic verification and pathogenicity analysis were performed, and maternal and infant outcomes were followed up. Results: Of 56 pregnant women with fetal Xp22.31 microdeletion, 43 underwent serological screening during the second trimester of pregnancy, of which 42 were abnormal (39 male fetuses and 3 female fetuses). The median uE₃ MoM value of 39 male fetuses [0.06 (0.00-0.21)] was lower than the normal value and significantly lower than that of fetuses with trisomy 21 [0.71 (0.26-1.27)] and fetuses with trisomy 18 [0.36 (0.15-0.84)], the difference was statistically significant (Z=99.96, P<0.001). While the MoM values of AFP and hCG were all within the normal range. Among the 56 fetuses carrying Xp22.31 microdeletion, 45 were male fetuses and 11 were female fetuses, and the deletion fragments all involved STS gene. Eighty-nine percent (50/56) were inherited from mother (49 cases) or father (1 case), and 11% (6/56) were de novo mutations. Follow-up showed 48 live births (38 males and 10 females) and 8 chose to terminate pregnancy (7 males and 1 female). Among the 38 male newborns, 37 presented with scaly skin changes from 1 to 3 months of age, and one had no clinical manifestations until 4 months after birth. Ten female newborns had no obvious clinical manifestations. Conclusions: The decrease levels of uE₃ MoM on maternal serological screening is closely related to the higher risk of XLI in male fetuses. For pregnant women with low uE₃ in serological screening or with family history of ichthyosis, in addition to chromosomal karyotype analysis, joint detection of genomic copy number variant analysis should be recommended.

[Mechanism of circZNF609 targeting miR-153 to regulate the proliferation and apoptosis of diffuse large B-cell lymphoma]

Objective: To investigate the molecular mechanism of circZNF609 targeting miR-153 to regulate the proliferation and apoptosis of diffuse large B-cell lymphoma. Methods: Fifty cases of lymphoma tissue from patients with diffuse large B-cell lymphoma who were diagnosed and treated in the First Affiliated Hospital of Zhengzhou University from July 2018 to December 2019 were collected. Thirty cases of normal lymph node tissues that were confirmed to be reactive hyperplasia by pathological diagnosis during the same period were selected as controls. Real time quantitative polymerase chain reaction (PCR) was used to detect the expression of circZNF609 in diffuse large B-cell lymphoma tissues and control hyperplasia lymph nodes. Diffuse large B-cell lymphoma OCI-LY19 cells were divided into control group (blank control), si-con group (transfected with siRNA control), si-ZNF609 group (transfected with circZNF609 siRNA), and si-ZNF609+ Anti-NC group (co-transfected with circZNF609 siRNA and inhibitor control) and si-ZNF609+ Anti-miR-153 group (co-transfected with circZNF609 siRNA and miR-153 inhibitor). Cell counting kit-8 (CCK-8) was used to detected proliferation, flow cytometry was used to detect cell cycle and apoptosis. Western blot was used to detect the protein expressions of C-caspase-3, cyclin D1, p21. The luciferase reporter system was used to identifie the relationship between circZNF609 and miR-153. Results: The expression level of circZNF609 in diffuse large B-cell lymphoma tissue was (1.44±0.22), higher than (0.37±0.14) in the control tissues (P<0.001). The cell survival rate of the si-ZNF609 group was (51.74±6.39)%, lower than (100.00±10.23)% of the control group and the (99.64±11.67)% of the si-con group (P<0.001). The proportion of cells in the G(0)/G(1) phase was (63.25±4.11)%, higher than (48.62±4.32)% of the control group and (47.12±3.20)% of the si-con group (P<0.001), the apoptosis rate was (13.36±1.42)%, higher than (3.65±0.47)% of the control group and (3.84±0.62)% of the si-con group (P<0.05). The expression levels of C-caspase-3 and p21 protein were (0.85±0.09) and (0.90±0.08), higher than (0.38±0.04) and (0.65±0.07) in the control group and (0.39±0.05) and (0.66±0.05) in the si-con group (P<0.001). The expression level of cyclin D1 protein was (0.40±0.03), lower than (0.52±0.06) of the control group and (0.53±0.04) of the si-con group (all P<0.001). CircZNF609 and miR-153 are mutually targeted. The cell survival rate of the si-ZNF609+ Anti-miR-153 group was (169.92±13.25)%, higher than (100.00±9.68)% of the si-ZNF609+ Anti-NC group (P<0.001), the ratio of cells in G(0)/G(1) phase and apoptosis rate were (52.01±3.62)% and (8.20±0.87)%, respectively, lower than (64.51±5.17)% and (14.03±1.17)% in the si-ZNF609+ Anti-NC group (P<0.001). The protein expression levels of C-caspase-3 and p21 were (0.42±0.06) and (0.52±0.06), lower than (0.80±0.07) and (0.92±0.10) of the si-ZNF609+ Anti-NC group (P<0.001). The protein expression level of cyclin D1 was (0.68±0.07), higher than (0.39±0.04) in the si-ZNF609+ Anti-NC group (P<0.001). Conclusion: Down-regulation of circZNF609 inhibits the proliferation of diffuse large B-cell lymphoma OCI-LY19 cells and induces apoptosis by targeting miR-153.

[Mechanism of paeoniflorin inhibiting apoptosis of hippocampal neurons of rats induced by lead acetate]

Objective: To investigate the effect and underlying mechanism of paeoniflorin on hippocampal neuron apoptosis induced by lead acetate. Methods: In September 2020, primary hippocampal neuronal cells were isolated and cultured from fetal rats, and identified using cellular immunofluorescent. MTT assay was used to measure the cell viability to determine the concentration and time of lead acetate-induced hippocampal neuron apoptosis. MTT was also used to evaluate the effect of paeoniflorin concentration on the apoptosis of hippocampal neurons induced by lead acetate. According to the results, different concentrations of paeoniflorin were selected to intervene hippocampal neuron cells, after 24 h, lead acetate was added to the cells, meanwhile, blank and model groups were set up, the content of reactive oxygen species (ROS) , superoxide dismutase (SOD) , lactate dehydrogenase (LDH) , malondialdehyde (MDA) and Caspase-3 were measured. Extracellular signal regulated kinase (ERK) , phosphorylated ERK (p-ERK) , p38 mitogen -activated protein kinases (p38MAPK) , phosphorylated p38MAPK (p-p38MAPK) , c-Jun N-terminal kinase (JNK) and phosphorylated JNK (p-JNK) protein expression in hippocampal neuronal cells were determined by Western blotting. Results: The isolated and cultured hippocampal neurons were identified by immunofluorescence chemical staining and then treated with lead acetate, MTT results showed that lead acetate had the best toxicity effect when treated for 24 h at a concentration of 25 μmol/L. Paeoniflorin showed no cytotoxic effect on hippocampal neuronal cells when the concentrations below 80 μmol/L. Compared with the model group, the activity of hippocampal neuronal cells was significantly increased after treating with 20, 40 or 80 μmol/L paeoniflorin (P<0.05) . Compared with the blank group, the ROS activity, LDH release level, MDA content and caspase-3 content were significantly increased (P<0.01) , and the SOD activity was significantly decreased (P< 0.01) in the hippocampal neuronal cells of the model group. Compared with the model group, the ROS activity, LDH release level, MDA content and caspase-3 content were obviously decreased (P<0.05) , SOD activity was significantly increased (P <0.01) after hippocampal neuronal cells were treated with 40 or 80 μmol/L paeoniflorin. Relative to the model group, the ratio of p-ERK/ERK were significantly up-regulated (P<0.01) , while the ratios of p-p38MAPK/p38MAPK and p-JNK/JNK were significantly down-regulated after hippocampal neuronal cells were treated with 40 or 80 μmol/L paeoniflorin (P<0.05) . Conclusion: Paeoniflorin may down-regulate the expression of p-p38MAPK and p-JNK protein, up-regulate the expression of p-ERK protein, and inhibit the apoptosis of hippocampal neurons induced by lead acetate through the MAPK signaling pathway.

Tumor necrosis factor-α-induced protein 8-like 2 Fosters Tumor-Associated Microbiota to Promote the Development of Colorectal Cancer

Although increasing evidence links the gut microbiota with the development of colorectal cancer, the molecular mechanisms for microbiota regulation of tumorigenesis are not fully understood. Here, we found that a member of the TNF-α-induced protein 8 (TNFAIP8) family called TIPE2 (TNFAIP8-like 2) was significantly upregulated in murine intestinal tumors and in human colorectal cancer (CRC), and colorectal cancer with high expression of Tipe2 mRNA associated with reduced survival time of patients. Consistent with these findings, TIPE2 deficiency significantly inhibited the development of CRC in mice treated with azoxymethane/dextran sodium sulfate and in Apcmin/+ mice. TIPE2 deficiency attenuated the severity of colitis by successfully resolving and restricting colonic inflammation and protected colonic myeloid cells from death during colitis. Transplantation of TIPE2-deficient bone marrow into WT mice successfully dampened the latter's tumorigenic phenotype, indicating a hematopoietic-specific role for TIPE2. Mechanistically, restricting the expansion of Enterobacteriaceae/E. coli decreased intestinal inflammation and reduced the incidence of colonic tumors. Collectively, these data suggest that hematopoietic TIPE2 regulates intestinal anti-tumor immunity by regulation of gut microbiota. TIPE2 may represent a new therapeutic target for treating CRC.

TIPE2 Promotes Tumor Initiation But Inhibits Tumor Progression in Murine Colitis-Associated Colon Cancer

BACKGROUND

Colorectal cancer (CRC) is the third leading cause of cancer in the United States, and inflammatory bowel disease patients have an increased risk of developing CRC due to chronic intestinal inflammation with it being the cause of death in 10% to 15% of inflammatory bowel disease patients. TIPE2 (TNF-alpha-induced protein 8-like 2) is a phospholipid transporter that is highly expressed in immune cells and is an important regulator of immune cell function.

METHODS

The azoxymethane/dextran sulfate sodium murine model of colitis-associated colon cancer (CAC) was employed in Tipe2 -/- and wild-type mice, along with colonoid studies, to determine the role of TIPE2 in CAC.

RESULTS

Early on, loss of TIPE2 led to significantly less numbers of visible tumors, which was in line with its previously described role in myeloid-derived suppressor cells. However, as time went on, loss of TIPE2 promoted tumor progression, with larger tumors appearing in Tipe2 -/- mice. This was associated with increased interleukin-22/STAT3 phosphorylation signaling. Similar effects were also observed in primary colonoid cultures, together demonstrating that TIPE2 also directly regulated colonocytes in addition to immune cells.

CONCLUSIONS

This work demonstrates that TIPE2 has dual effects in CAC. In the colonocytes, it works as a tumor suppressor. However, in the immune system, TIPE2 may promote tumorigenesis through suppressor cells or inhibit it through IL-22 secretion. Going forward, this work suggests that targeting TIPE2 for CRC therapy requires cell- and pathway-specific approaches and serves as a cautionary tale for immunotherapy approaches in general in terms of colon cancer, as intestinal inflammation can both promote and inhibit cancer.

Slfn4 deficiency improves MAPK-mediated inflammation, oxidative stress, apoptosis and abates atherosclerosis progression in apolipoprotein E-deficient mice

BACKGROUND AND AIMS

Atherosclerosis, a progressive inflammatory disease characterized by elevated inflammation and lipid accumulation in the aortic endothelium, arises in part from the infiltration of inflammatory cells into the vascular wall. However, it is not fully defined how inflammatory cells, especially macrophages, affect the pathogenesis of atherosclerosis. Schlafen4 (Slfn4) mRNA is remarkably upregulated upon ox-LDL stimulation in macrophages. Nonetheless, the role of Slfn4 in foam cell formation remains unclear.

METHODS

To determine whether and how Slfn4 regulates lesion macrophage function during atherosclerosis，we engineered ApoE-/-Slfn4-/- double-deficient mice on an ApoE-/- background and evaluated the deficiency of Slfn4 expression in atherosclerotic lesion formation in vivo.

RESULTS

Our results demonstrate that total absence of SLFN4 and the bone marrow-restricted deletion of Slfn4 in ApoE-/- mice remarkably diminish inflammatory cell numbers within arterial plaques as well as limit development of atherosclerosis in moderate hypercholesterolemia condition. This is linked to a marked reduction in the expression of proinflammatory cytokines, the generation of the reactive oxygen species (ROS) and the apoptosis of cells. Furthermore, the activation of MAPKs and apoptosis signaling pathways is compromised in the absence of Slfn4.

CONCLUSIONS

These findings demonstrate a novel role of Slfn4 in modulating vascular inflammation and atherosclerosis, highlighting a new target for the related diseases.

PPA1 Promotes Breast Cancer Proliferation and Metastasis Through PI3K/AKT/GSK3β Signaling Pathway

Breast cancer is the most common malignancy among women. Inorganic pyrophosphatase 1 (PPA1) is a multifunctional protein involved in the development of several tumors. However, the role of PPA1 in breast cancer progression remains unclear. In this study, we found that PPA1 was highly expressed in breast cancer compared to its levels in normal breast tissue and that it was correlated with breast cancer clinicopathological characteristics, as well as poor survival in breast cancer patients. Silencing PPA1 restrained breast cancer proliferation and metastasis by regulating Slug-mediated epithelial-mesenchymal transition (EMT). Opposite results were observed following PPA1 overexpression. In addition, investigation of the underlying mechanism demonstrated that PPA1 ablation led to decrease phosphatidylinositol 3 kinase (PI3K) phosphorylation levels and attenuate phosphorylated AKT and glycogen synthase kinase-3 β (GSK3β), while ectopic PPA1 expression had the opposite effects. Moreover, PI3K inhibitors suppress the signaling pathways mediating the effects of PPA1 on breast cancer, resulting in tumor growth and metastasis suppression in vitro and in vivo. In summary, our results verify that PPA1 can act as an activator of PI3K/AKT/GSK3β/Slug-mediated breast cancer progression and that it is a potential therapeutic target for the inhibition of tumor progression.

OP0090 CLASSIFICATION OF PATIENTS WITH RELAPSING POLYCHONDRITIS BASED ON SOMATIC MUTATIONS IN UBA1

Background:

Somatic mutations in ubiquitin activating enzyme 1 (UBA1) cause a newly defined syndrome known as VEXAS. [1] More than fifty percent of patients currently identified with VEXAS meet diagnostic criteria for relapsing polychondritis (RP).

Objectives:

To determine the prevalence VEXAS within a cohort of patients with RP, to compare their clinical, laboratory, and immunologic features and to develop a clinical algorithm to inform genetic screening for VEXAS among patients with RP.

Methods:

Exome and targeted sequencing of the UBA1 gene was performed in a prospective observational cohort of patients with RP. Clinical and immunological characteristics of patients with RP were compared based on presence or absence of UBA1 mutations. Random forest was used to derive a clinical algorithm to identify patients with UBA1 mutations. Immune populations were quantified by multipanel flow cytometry. Categorical and continuous variables were compared using the chi square or Kruskal-Wallis test. P<0.05 defined statistical significance.

Results:

Seven of 92 patients with RP (7.6%) were confirmed to have UBA1 mutations (VEXAS-RP). Six additional patients with VEXAS-RP from other cohorts were included for subsequent analyses. Patients with VEXAS-RP were all male, older at disease onset, and commonly had fever, ear chondritis, skin involvement, deep vein thrombosis, and pulmonary infiltrates. Patients with RP as compared with VEXAS-RP had a significantly higher prevalence of airway chondritis, costochondritis and tenosynovitis/arthralgias. (Table). Mortality was significantly greater in VEXAS-RP than RP (27% vs 2% p=0.01). Maximum ESR, CRP, and mean corpuscular volume (MCV) values were significantly greater in VEXAS-RP. Absolute monocyte, lymphocyte, and platelet counts were significantly lower in VEXAS-RP. A decision tree based on male sex, MCV>100 fl and Platelet count<200 K/ul classified between VEXAS-RP and RP with 100% sensitivity and 96% specificity.

Table 1.

Clinical Characteristics of patients with RP vs VEXAS-RP

All Patientsn=98RPn=85VEXAS-RPn=13p valueDemographic CharacteristicsRace, White n (%)90 (92)77 (91)13 (100)0.59Sex, Male n (%)26 (27)13 (15)13 (100)<0.0001Age, Symptom onset, years, Median (IQR)38 (30-47)37 (28-43)56 (54-64)<0.0001Clinical SymptomsFever n (%)33 (34)20 (24)13 (100)<0.0001Ear chondritis n (%)61 (62)48 (56)13 (100)0.0015Nose chondritis n (%)83 (85)71 (84)12 (92)0.68Airway chondritis n (%)37 (38)37 (44)0 (0)0.0015Tenosynovitis/arthalgias n (%)83 (85)77 (91)6 (46)0.0005Skin involvement n (%)33 (34)22 (2611 (85)<0.0001Laboratory ValuesESR, mm/hr, median (IQR)12 (6-22)11 (5-19)66.5 (42-110)<0.0001CRP, mg/L, median (IQR)2.9 (0.8-9.6)1.9 (0.6-6.3)17.7 (9.6-99.5)<0.0001Platelet count (k/uL)246(201-299)258 (227-312)145 (100-169)<0.0001MCV fL93.05 (90-98)92.2 (89-95)105 (102-115)<0.0001Absolute lymphocyte count1.6 (1.1-2.3)1.78(1.4-2.4)0.92 (0.5-1.2)<0.0001CT scan abnormalitiesPulmonary infiltrates n (%)16 (16.33)6 (7.06)10 (77)<0.0001ComplicationsDeath n (%)6 (6)3 (4)3 (23)0.029Unprovoked DVT12 (12)4 (5)8 (62)<0.0001

N number; IQR = interquartile range

Conclusion:

Mutations in UBA1 are causal for disease in a subset of patients with RP. These patients are defined by disease onset in the fifth decade of life or later, male sex, ear/nose chondritis and hematologic abnormalities. Early identification is important in VEXAS given the associated high mortality rate.

References:

[1]Beck DB, Ferrada MA, Sikora KA, Ombrello AK, Collins JC, Pei W, Balanda N, Ross DL, Ospina Cardona D, Wu Z et al: Somatic Mutations in UBA1 and Severe Adult-Onset Autoinflammatory Disease. N Engl J Med 2020, 383(27):2628-2638.

Disclosure of Interests:

None declared

[Application of aldosterone/direct renin ratio before drug washout in the screening of primary aldosteronism]

Objective: To explore the cut-off point of aldosterone/direct renin ratio (ADRR) before drug washout in the screening for primary aldosteronism (PA) in the Chinese population and reduce the potential risk caused by drug washout during PA screening. Methods: Hospitalized hypertensive patients in the Hypertension Ward of Fuwai Hospital, Chinese Academy of Medical Sciences from January 2017 to October 2019 were enrolled. PA was diagnosed according to the criterion of 2016 American Guideline and 2016 Chinese Consensus for PA. The plasma aldosterone concentration (PAC), direct renin concentration (DRC) and ADRR before and after drug washout were measured. The receiver operating characteristic (ROC) curve of ADRR was drawn and the maximal Youden index was used to determine the best cut-off value. Results: A total of 542 hypertensive patients were included, with 467 patients diagnosed with essential hypertension (EHT) (297 males and 170 females), and 75 patients diagnosed with PA (51 males and 24 females). Patients with PA had higher PAC and ADRR before and after drug washout than those with EHT(150.0 (130.0, 210.0) vs 120.0 (80.0, 170.0) ng/L, 170.0 (120.0, 260.0) vs 130.0 (90.0, 180.0) ng/L; 28.9 (15.9, 63.5) vs 4.3 (1.9, 11.8) (ng/L) / (mU/L) , 55.6 (39.0, 109.0) vs 9.8 (4.5, 21.3) (ng/L) /(mU/L), all P<0.001). However, DRC of PA patients before and after washout were lower than those with EHT (4.0 (2.0, 10.0) vs 27.0 (10.0, 64.0) mU/L, 3.0 (2.0, 4.0) vs 12.2 (5.0, 27.0) mU/L, P<0.001). In EHT and PA groups, PAC and ADRR significantly increased (P=0.001, P<0.001) , but DRC significantly decreased after drug washout (all P<0.001) . The area under the ROC curve of ADRR before drug washout was 0.868 (95%CI 0.836-0.895) with the best cut-off value of 7.8 (ng/L) / (mU/L) for the screening of PA .The sensitivity and specificity was 94.7% and 66.8%, respectively, with the maximal Youden index of 0.615. Conclusion: ADRR before drug washout > 7.8 (ng/L) / (mU/L) can be used as an alternative cut-off point to screen PA when drug washout is not available.

Inactivation of TMEM106A promotes lipopolysaccharide-induced inflammation via the MAPK and NF-κB signaling pathways in macrophages

Pattern recognition receptors, such as Toll-like receptors (TLRs), play an important role in the host defense against invading microbial pathogens. Their activation must be precisely regulated, as inappropriate activation or overactivation of TLR signaling pathways may result in inflammatory disorders, such as septic shock or autoimmune diseases. TMEM106A is a type II transmembrane protein constitutively expressed in macrophages. Our current study demonstrated that TMEM106A levels were increased in macrophages upon lipopolysaccharide (LPS) stimulation, as well as in the peripheral monocytes of patients with sepsis. Tmem106a knockout mice were more sensitive to lipopolysaccharide (LPS)-induced septic shock than wild-type mice. Further experiments indicated that Tmem106a ablation enhanced the expression of CD80, CD86 and major histocompatibility complex (MHC)-II in mouse macrophages upon LPS stimulation, accompanied with up-regulation of tumor necrosis factor (TNF)-α, interleukin (IL)-6, interferon (IFN)-β and inducible nitric oxide synthase (iNOS), indicating the activation of macrophages and polarization towards the M1 inflammatory phenotype. Moreover, elevated mitogen-activated protein kinase (MAPK) and nuclear factor kappa B (NF-κB) signaling were found to be involved in the LPS-induced inflammatory response in Tmem106a^-/- macrophages. However, this effect was largely abrogated by macrophage deletion in Tmem106a^-/- mice. Therefore, deficiency of Tmem106a in macrophages may enhance the M1 polarization in mice, resulting in inflammation. This suggests that TMEM106A plays an important regulatory role in maintaining macrophage homeostasis.

The SARS-CoV-2 Spike Glycoprotein Biosynthesis, Structure, Function, and Antigenicity: Implications for the Design of Spike-Based Vaccine Immunogens

The ongoing pandemic of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), poses a grave threat to global public health and imposes a severe burden on the entire human society. Like other coronaviruses, the SARS-CoV-2 genome encodes spike (S) glycoproteins, which protrude from the surface of mature virions. The S glycoprotein plays essential roles in virus attachment, fusion and entry into the host cell. Surface location of the S glycoprotein renders it a direct target for host immune responses, making it the main target of neutralizing antibodies. In the light of its crucial roles in viral infection and adaptive immunity, the S protein is the focus of most vaccine strategies as well as therapeutic interventions. In this review, we highlight and describe the recent progress that has been made in the biosynthesis, structure, function, and antigenicity of the SARS-CoV-2 S glycoprotein, aiming to provide valuable insights into the design and development of the S protein-based vaccines as well as therapeutics.

The TIPE Molecular Pilot That Directs Lymphocyte Migration in Health and Inflammation

Lymphocytes are some of the most motile cells of vertebrates, constantly navigating through various organ systems. Their specific positioning in the body is delicately controlled by site-specific directional cues such as chemokines. While it has long been suspected that an intrinsic molecular pilot, akin to a ship's pilot, guides lymphocyte navigation, the nature of this pilot is unknown. Here we show that the TIPE (TNF-α-induced protein 8-like) family of proteins pilot lymphocytes by steering them toward chemokines. TIPE proteins are carriers of lipid second messengers. They mediate chemokine-induced local generation of phosphoinositide second messengers, but inhibit global activation of the small GTPase Rac. TIPE-deficient T lymphocytes are completely pilot-less: they are unable to migrate toward chemokines despite their normal ability to move randomly. As a consequence, TIPE-deficient mice have a marked defect in positioning their T lymphocytes to various tissues, both at the steady-state and during inflammation. Thus, TIPE proteins pilot lymphocytes during migration and may be targeted for the treatment of lymphocyte-related disorders.

The SCFβ-TrCP E3 Ubiquitin Ligase Regulates Immune Receptor Signaling by Targeting the Negative Regulatory Protein TIPE2

TNFAIP8-like 2 (TIPE2) is a negative regulator of immune receptor signaling that maintains immune homeostasis. Dysregulated TIPE2 expression has been observed in several types of human immunological disorders. However, how TIPE2 expression is regulated remains to be determined. We report in this study that the SCF^β-TrCP E3 ubiquitin ligase regulates TIPE2 protein abundance by targeting it for ubiquitination and subsequent degradation via the 26S proteasome. Silencing of either cullin-1 or β-TrCP1 resulted in increased levels of TIPE2 in immune cells. TAK1 phosphorylated the Ser³ in the noncanonical degron motif of TIPE2 to trigger its interaction with β-TrCP for subsequent ubiquitination and degradation. Importantly, the amount of TIPE2 protein in immune cells determined the strength of TLR 4-induced signaling and downstream gene expression. Thus, our study has uncovered a mechanism by which SCF^β-TrCP E3 ubiquitin ligase regulates TLR responses.

Expression of Normal or Mutated X-Linked BCOR Transcripts in OFCD iPSCs

Reprogramming diseased cells with mutated genes into induced pluripotent stem cells (iPSCs) can allow studies of disease mechanism and correct the mutation. Oculofaciocardiodental (OFCD) syndrome is a developmental disorder caused by heterozygous mutations in the X-linked BCL-6 corepressor (BCOR) gene. In this present study, we aimed to reprogram stem cells from a tooth apical papilla (SCAP) of a patient with OFCD, termed SCAP-O, into iPSCs. The SCAP-O carry a copy of the BCOR gene having 1 nucleotide deletion in 1 of the alleles, therefore harboring a mixture of cells expressing either normal (SCAP-O^BCOR-WT) or mutated (SCAP-O^BCOR-mut) BCOR transcripts. We subcloned SCAP-O and separated SCAP-O^BCOR-WT and SCAP-O^BCOR-mut as verified by sequencing. The selected subclone SCAP-O^BCOR-mut expressed only the mutated BCOR transcripts and remained in such condition after multiple passages. We reprogrammed SCAP-O and subclone SCAP-O^BCOR-mut into transgene-free iPSCs using an excisable lentiviral vector system (hSTEMCCA-loxP) carrying 4 reprogramming factors in a single cassette, followed by removal of transgenes via Cre-mediated excision. We found that after reprogramming SCAP-O or subclone SCAP-O^BCOR-mut into iPSCs, some of the iPSC clones expressed either solely the normal BCOR-WT or BCOR-mut transcripts, while other clones expressed both BCOR-WT and BCOR-mut transcripts. This is our first step toward establishing OFCD study models by generating isogenic control BCOR-WT iPSCs versus BCOR-mut iPSCs.