Investigative biological therapies for primary Sjögren's syndrome.

Primary Sjögren's syndrome (pSS) is a chronic, systemic autoimmune disease characterized by dryness of the eyes and mouth. The histological feature is mononuclear cell infiltration in exocrine glands, primarily salivary and lachrymal glands. As the disease progresses, some other tissues and organs may be involved and extraglandular manifestations ensue. The major current treatments are palliative and empirical, and in most cases the outcomes are not satisfactory. Emerging data indicate a critical role of lymphocytes in its development and progression. While pioneering work targeting B cells has demonstrated some encouraging results, more trials are warranted to validate the safety and efficacy. In addition, modulation of T cell function with abatacept ameliorates the severity of pSS. Furthermore, clinical trials to inhibit important cytokines involved in its formation have been carried out. In this article, we summarize and compare current biological therapies in order to find new and effective treatments for pSS.

Clinical features and independent predictors of Behçet's disease associated with myelodysplastic syndrome.

OBJECTIVES: To investigate the correlation of Behçet's disease (BD) with myelodysplastic syndrome (MDS) and identify the predictive risk factors in Chinese patients. METHODS: A retrospective study of BD associated with MDS (BD-MDS) patients from the First Affiliated Hospital of Zhengzhou University was conducted. RESULTS: Among 15 BD-MDS patients, 10 were females and 5 males. While 13 (86.7%) patients had abnormal karyotype, 11 patients with trisomy 8. 10 (66.7%) had gastrointestinal (GI) involvement. Compared with 60 general BD patients without MDS, the BD-MDS patients were significantly older. In addition, fever and GI involvement were more common in BD-MDS patients, whereas these patients had lower levels of leukocyte count, haemoglobin, and platelet count (p<0.05). Logistic regression analysis showed that GI involvement, low haemoglobin, and high ESR level were independently associated with the development of MDS in BD patients. BD-MDS patients with GI involvement (IBD-MDS) were usually much older and have more fever than IBD patients without MDS, as well as lower leukocyte count, haemoglobin level, platelet count, and higher erythrocyte sedimentation rate (ESR) and C-reactive protein levels (p<0.05). By comparison with 60 primary MDS patients without BD, the BD-MDS patients had more abnormal karyotypes and more trisomy 8 (p<0.05), while the distribution of 2016 WHO subtypes of MDS and IPSS-R categories were similar. CONCLUSIONS: Our findings suggest that cytogenetic abnormalities, especially trisomy 8, may play a role in the association of GI involvement, BD, and MDS. GI involvement, low haemoglobin, and high ESR level were independent predictors for MDS development in BD patients.

Teriparatide prevented synovial inflammation and cartilage destruction in mice with DMM.

AIM: Emerging data have demonstrated that low-grade inflammation in osteoarthritis, a long-held degenerative disease. The inflamed synovium produces various cytokines that induce cartilage destruction and joint pain. A previous study showed that teriparatide, an FDA approved anti-osteoporotic drug, may enhance cartilage repair. Our study focuses on its role in OA synovitis. MATERIALS AND METHODS: Primary mouse articular chondrocytes were used to determine the most potent cytokines involved in OA inflammation and cartilage destruction. A destabilization of the medial meniscus mouse model was established to investigate the effect of teriparatide in OA, particularly, on synovial inflammation and cartilage degradation. RESULTS: In vitro experiments showed that TNF-α was the most potent inducer of cartilage matrix-degrading enzymes, and that teriparatide antagonized the TNF-α of effect. Consistently, articular cartilage samples from TNF-α transgenic mice contained more MMP-13 positive chondrocytes than those from wild type mice. In addition, more type II collagen was cleaved in human OA cartilage than in normal cartilage samples. CONCLUSIONS: Teriparatide can prevent synovitis and cartilage degradation by suppressing TNF-α mediated MMP-13 overexpression. Together with its chondroregenerative capability, teriparatide may be the first effective disease modifying osteoarthritis drug.

Characterisation of Disease Patterns of Dermatomyositis with Different Initial Manifestations.

Purpose: To determine the characteristics and prognoses of dermatomyositis (DM) by comparing the difference in initial symptoms. Patients and Methods: A retrospective analysis was performed on the patients diagnosed with DM from 1 January 2019 to 1 January 2021. Based on the firstly presented symptoms, patients were divided into five groups, namely rash group, muscle weakness group, arthritis group, respiratory symptom group and atypical symptom group. Clinical and laboratory data were recorded. All patients were followed up until 31 May 2021. Results: In total 136 DM patients, rash (40%) was the most common initial symptom, followed by respiratory symptoms (22%), arthritis (20%), muscle weakness (10%) and atypical symptoms (8%). Rash group and atypical group had a higher positive rate of anti-TIF1γ antibodies than arthritis group and respiratory symptom group (P < 0.05). Respiratory symptom and arthritis groups had a higher positive rate of anti-Ro52 antibodies than rash and muscle weakness groups (P < 0.05). Respiratory group had a higher incidence of ILD than rash and atypical groups. The FVC and DLCO in respiratory group were significantly lower than rash group, arthritis group and atypical group (P < 0.05). The survival rate of rash group was significantly higher than muscle weakness group and arthritis group (P < 0.05). Conclusion: DM patients with different initial manifestations had different myositis antibodies and prognoses.

QRISK3-based analysis of cardiovascular risk factors in patients with long-term but well-controlled systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a multisystem inflammatory disease of unknown etiology. Corticosteroids and immunosuppressive agents are the principal forms of treatment for this condition. While cardiovascular disease (CVD) is known to be a major cause of death in patients with SLE, there has been no improvement over the last few decades with regard to diagnosis, treatment, or prognosis. The QRISK3 algorithm is a new algorithm that includes SLE-related risk factors; this tool can predict the risk of CVD over a ten-year period. In this study, involving 180 patients, we compared the performance of the Framingham risk score, the recalibrated risk prediction SCORE, and QRISK3 for the assessment of CVD in patients with a long course of disease and low disease activity. Then, we used a more efficient algorithm, QRISK3 to identify the risk factors for CVD. This was a prospective and cross-sectional study involving 116 patients. All patients fulfilled the ACR criteria. The systemic lupus erythematosus disease activity index 2000 (SLEDAI-2K) is widely used to assess disease activity in SLE patients; patients with a SLEDAI-2K less than or equal to 4 are considered to be stable. Thus, we defined well-controlled patients as those with a SLEDAI-2K score less than or equal to 4. The dose of glucocorticoid (GC) that patients received was less or equal to 10 mg per day. We recorded and assessed a range of traditional risk factors, current treatments, comorbidities, data at the time of onset, and SLE-related evaluations. The QRISK3 score, and the relative risk (RR) that this score defined, were used to estimate the risk of CVD in patients with SLE. According to these relative risks, the patients were divided into low- (n=28), intermediate- (n=46), and high-relative risk (n=31) groups for subgroup analysis. Of the 116 patients enrolled, 105 were eligible to be assessed for the risk of CVD. By univariate analyses, the RR was significantly related with age at the time of enrolment (p<0.001), age at onset (p<0.001), resting heart rate (RHR) (p<0.001), present dose of GCs (p<0.001), present SLEDAI-2K (p=0.015), aerobic exercise (p<0.001), initial SLEDAI-2K (p<0.001), and initial dose of GCs (p=0.048). In the multiple linear regression model, the RR of CVD was significantly correlated with the initial SLEDAI-2K score (ß=2.112, p<0.001), initial dose of GCs (ß=-0.009, p=0.041), resting heart rate (ß=0.241, p=0.003) and age at onset (ß=-0.208, p=0.004). Pearson's correlation showed that RHR was significantly associated with aerobic exercise (r=-0.322, p=0.001). Subgroup analysis further identified a positive correlation between the history of nephritis, metabolic syndrome (MetS), aerobic exercise, present dose of GCs, and the RR of CVD. Patients with long-term but well-controlled SLE had a high relative risk of CVD and that this was associated with resting heart rate (P=0.003), history of lupus nephritis (P<0.001), initial SLEDAI-2K score (P<0.001), and metabolic syndrome (P=0.017). However, age at onset (P<0.001), use of hydroxychloroquine (P=0.30) and Mycophenolate mofetil (P=0.01), and the initial dose of glucocorticoid (P=0.049), were protective factors. Younger SLE patients had a significantly higher relative risk of CVD than older patients (p<0.001). QRISK3 detected more SLE patients at high risk of CVD when compared to the Framingham and recalibrate SCORE. To reduce the risk of CVD in SLE patients, measures should be taken both during the initial stages of disease and for long-term management.

Exploring the Association Between History of Psoriasis (PSO) and Disease Activity in Patients with Psoriatic Arthritis (PsA).

INTRODUCTION: Psoriatic arthritis (PsA) is a common inflammatory disease affecting the peripheral and axial skeleton. History of psoriasis (PSO), either personal or family history, is an important factor in the diagnosis of PsA. We investigated the association between history of PSO and clinical characteristics of PsA. METHODS: PsA patients were consecutive recruited from 2019 to 2020. These patients were subjected to clinical, biochemical, and radiographic examinations, and disease activity was evaluated. Continuous and categorical variables analyses were presented. RESULTS: All registered patients (296 cases) met the classification criteria of PsA. They were divided into three groups based on the history of psoriasis (PSO), as: (1) 145 patients with PSO themselves (pPsA); (2) 96 patients with family history of PSO (fPsA); (3) 55 patients with family history and coexisting PSO themselves (fPsA/PSO). Compared to fPsA/PSO, the levels of CRP, ESR, uric acid, DAPSA, BASDAI, ASDAS, and BASFI were lower in fPsA, but similar to pPsA. The severity of sacroiliitis tended to be more severe in fPsA/PSO than fPsA (OR2 vs. 3 0.508; 95% CI 0.272 to 0.949, p < 0.05). No significant differences were found in HLA-B-27 and common inflammatory articular and extra-articular manifestations among the three groups. Furthermore, there were no differences in LEI, TJC, SJC, and DAS28CRP. Interestingly, a correlation was found between the ages of individuals with PSO and the onset of arthritis, and the earliest arthritis onset occurred in fPsA/PSO patients (p < 0.001). CONCLUSIONS: Our study demonstrates that currently existing cutaneous lesions in patients themselves are correlated with disease activity and severity of axial joint damage, whereas family history does not have an evident impact on the disease activity of PsA.

Dactylitis Is Associated With More Severe Axial Joint Damage and Higher Disease Activity in Axial Psoriatic Arthritis.

OBJECTIVE: To investigate the association of dactylitis with disease activity and the severity of damage detected by radiography in patients with axial psoriatic arthritis (axPsA). METHODS: Patients with axPsA who met the Classification Criteria for Psoriatic Arthritis were recruited. Clinical data, radiographic changes, and disease activity in patients with axPsA with or without dactylitis were compared using t tests, Mann-Whitney U tests, or Kruskal-Wallis tests for continuous variables. Chi-square or Fisher exact tests were used for categorical variables, and logistic regression analysis was performed to evaluate the association between dactylitis and damage detected by radiography. RESULTS: A total of 186 patients with axPsA were analyzed and dichotomized according to the presence or absence of dactylitis. Patients with dactylitis, as compared to those without dactylitis, had higher C-reactive protein (P = 0.004), erythrocyte sedimentation rate (P = 0.006), neutrophil-to-lymphocyte ratio (P = 0.04), and platelet-to-lymphocyte ratio (P = 0.02). In addition, patients with dactylitic axPsA, as compared to patients with nondactylitic axPsA, had higher tender joint counts, swollen joint counts, Disease Activity Index for Psoriatic Arthritis (DAPSA) scores, and Health Assessment Questionnaire scores (P < 0.001). Patients with axPsA who had dactylitis, as compared to those who did not, also had higher values for the Disease Activity Score in 28 joints, Ankylosing Spondylitis Disease Activity Score, Bath Ankylosing Spondylitis Functional Index, and Bath Ankylosing Spondylitis Disease Activity Index (P < 0.05), while fewer of these patients met the criteria for minimal disease activity and low disease activity (P < 0.05). Consistently, they had more severe damage as detected by radiography (P < 0.05), higher sacroiliac scores (odds ratio [OR] 2.08, 95% CI 1.14-3.79; P = 0.02), and a more significant reduction in bone mass density (OR 2.42, 95% CI 1.34-4.37; P = 0.003). No statistical differences were observed regarding HLA-B27 and the Leeds Enthesitis Index between these 2 groups of patients. Notably, only half of the patients with dactylitic axPsA had inflammatory back pain. CONCLUSION: Our study demonstrated that patients with axPsA who had dactylitis had higher disease activity and more severe joint damage compared to those without dactylitis. Careful examination and proper management of axial involvement are recommended.

Bone Marrow Mesenchymal Stem Cells Overexpressing HIF-1α Prevented the Progression of Glucocorticoid-Induced Avascular Osteonecrosis of Femoral Heads in Mice.

Glucocorticoid (GC)-induced avascular osteonecrosis of femoral head (AOFH) is a devastating complication, and no cures are currently available for it. Previous studies have demonstrated that implantation of bone marrow mesenchymal stem cells (BMMSCs) may prevent the progression of pre-collapse AOFH. Based on previous observations, we hypothesized that GCs induce AOFH via the COX-2 (cyclooxygenase-2)-PGE-2 (prostaglandin E2)-HIF-1α (hypoxia-inducible factor-1α) axis, and that modification of BMMSCs may improve the efficacy of their implantation. BMMSCs isolated from wild-type (WT) mice were treated with dexamethasone (Dex) and the results showed that Dex repressed the expression of COX-2. Femoral head samples harvested from both WT and COX-2 knock-out (COX-2-/-) mice were subjected to micro-computed tomography and histological examinations. Compared with their WT littermates, COX-2-/- mice had larger trabecular separations, diminished microvasculature, and reduced HIF-1α expression in their femoral heads. In vitro angiogenesis assays with tube formation and fetal metatarsal sprouting demonstrated that Dex repressed angiogenesis and PGE-2 antagonized its effects. An AOFH model was successfully established in C57BL/6J mice. In vitro experiment showed that BMMSCs infected with Lentivirus encoding HIF-1α (Lenti-HIF-1α) resulted in a robust increase in the production of HIF-1α protein. Implantation of BMMSCs overexpressing HIF-1α into femoral heads of AOFH mice significantly reduced osteonecrotic areas and enhanced bone repair, thus largely preserving the structural integrity of femoral heads. Our studies provide strong rationales for early intervention with core decompression and implantation of modified BMMSCs for GC-induced AOFH, which may spare patients from expensive and difficult surgical procedures.

Risk factors for progression of interstitial lung disease in Sjögren's syndrome: a single-centered, retrospective study.

OBJECTIVE: To identify clinical characteristics and risk factors related to the progression of interstitial lung disease (ILD) in patients with primary Sjögren's syndrome (pSS). METHODS: In this single-centered, retrospective study, a total of 83 identified pSS-ILD patients with relatively complete clinical data were finally enrolled. Clinical symptoms, laboratory data, high-resolution computed tomography (HRCT), and pulmonary function test (PFT) results were collected. A logistic regression analysis was performed to determine the independent risk factors for ILD progression, and a nomogram was plotted to construct a predictive model. RESULTS: The prevalence of pSS-ILD in our study was 18.89%. Among the 83 enrolled patients, 32 (38.6%) underwent ILD progression. The characteristic features associated with the progression of ILD included male sex, non-sicca onset, reticular pattern on HRCT, higher levels of baseline lactic dehydrogenase (LDH), and low baseline forced vital capacity (FVC). The results of multivariate logistic regression indicated that LDH (OR 1.008, p = 0.030) was an independent risk factor for ILD progression, while sicca onset (OR 0.254, p = 0.044) and FVC (OR 0.952, p = 0.003) were protective factors for ILD progression. A simple predictive model for ILD progression in pSS was developed and validated. CONCLUSION: pSS patients with non-sicca onset, high baseline LDH level, and low baseline FVC were at higher risk of ILD progression.

Intravenous immunoglobulin for interstitial lung diseases of anti-melanoma differentiation-associated gene 5-positive dermatomyositis.

OBJECTIVE: Rapidly progressive interstitial lung disease (RP-ILD) in DM patients positive for anti-melanoma differentiation-associated gene 5 (anti-MDA5) autoantibody (MDA5-DM) often have a poor prognosis, frequently fatal. As there is a scarcity of data regarding the effect of intravenous immunoglobulin (IVIG) on RP-ILD in MDA5-DM patients (MDA5-RPILD), we conducted this study to determine the efficacy of a IVIG add-on initial treatment. METHODS: Patients with newly-onset MDA5-RPILD from September 2018 to June 2020 were retrospectively reviewed for 6 months in the First Affiliated Hospital of Zhengzhou University. They were divided into two groups: IVIG and non-IVIG groups. The major measurement of treatment outcome was the difference in the mortality in 3-month and 6-month between two group patients. Other relevant indicators were also recorded, including the incidence of infection, the dosages of GCs, the remission rate and the variables in laboratory data. RESULTS: The IVIG group (n = 31) showed significantly lower 6-month mortality rate than the non-IVIG group (n = 17) (22.6% vs 52.9%; P =0.033). The IVIG group patients had a higher remission rate at 3 months (71.0% vs 41.2%; P =0.044). Gradual reduction was observed in the first 3 months with regard to the titre of anti-MDA5 autoantibody, the serum level of ferritin and the ground glass opacification GGO scores. CONCLUSION: IVIG adjunct therapy is a very effective first-line treatment for patients with MDA5-RPILD. IVIG may increase the survival and remission rate by lowering ferritin concentration, anti-MDA5 titre and GGO score.

Aging, Cell Senescence, the Pathogenesis and Targeted Therapies of Osteoarthritis.

Osteoarthritis (OA) is a chronic, debilitating joint disease characterized by progressive destruction of articular cartilage. For a long time, OA has been considered as a degenerative disease, while recent observations indicate the mechanisms responsible for the pathogenesis of OA are multifaceted. Aging is a key factor in its development. Current treatments are palliative and no disease modifying anti-osteoarthritis drugs (DMOADs) are available. In addition to articular cartilage degradation, cellular senescence, synovial inflammation, and epigenetic alterations may all have a role in its formation. Accumulating data demonstrate a clear relationship between the senescence of articular chondrocytes and OA formation and progression. Inhibition of cell senescence may help identify new agents with the properties of DMOADs. Several anti-cellular senescence strategies have been proposed and these include sirtuin-activating compounds (STACs), senolytics, and senomorphics drugs. These agents may selectively remove senescent cells or ameliorate their harmful effects. The results from preclinical experiments and clinical trials are inspiring. However, more studies are warranted to confirm their efficacy, safety profiles and adverse effects of these agents.

Mesothelin-targeted CAR-T cells for adoptive cell therapy of solid tumors.

Significant progresses have been made in adoptive cell therapy with CAR-T cells for cancers, especially for hematological malignancies. However, the treatment of solid tumors still poses a tremendous challenge and remains an unmet medical need. Several factors are held responsible for the inadequate responses: tumor heterogeneity, inefficient homing of T cells to tumor tissues, immunosuppressive microenvironment and the shortage of specific antigens shortage. Mesothelin is a cell-surface glycoprotein highly expressed in many types of solid tumors. As such, it has attracted much attention as a molecular target in cancer immunotherapy. Here, we delineate the barriers imposed by solid tumors on CARs, outline the rationale of mesothelin as a target for immunotherapy, summarize the preclinical and clinical results of mesothelin-targeted therapies, and extrapolate the expected results of CAR-T cells directed against mesothelin for solid tumors.

Recent Progresses in the Treatment of Osteoporosis.

Osteoporosis (OP) is a chronic bone disease characterized by aberrant microstructure and macrostructure of bone, leading to reduced bone mass and increased risk of fragile fractures. Anti-resorptive drugs, especially, bisphosphonates, are currently the treatment of choice in most developing countries. However, they do have limitations and adverse effects, which, to some extent, helped the development of anabolic drugs such as teriparatide and romosozumab. In patients with high or very high risk for fracture, sequential or combined therapies may be considered with the initial drugs being anabolic agents. Great endeavors have been made to find next generation drugs with maximal efficacy and minimal toxicity, and improved understanding of the role of different signaling pathways and their crosstalk in the pathogenesis of OP may help achieve this goal. Our review focused on recent progress with regards to the drug development by modification of Wnt pathway, while other pathways/molecules were also discussed briefly. In addition, new observations made in recent years in bone biology were summarized and discussed for the treatment of OP.

Histamine H3 Receptor Signaling Regulates the NLRP3 Inflammasome Activation in C2C12 Myocyte During Myogenic Differentiation.

NLRP3 inflammasome has been implicated in impaired post-injury muscle healing and in muscle atrophy. Histamine receptors play an important role in inflammation, but the role of histamine H3 receptor (H3R) in myocyte regeneration and in the regulation of NLRP3 inflammasome is not known. We studied the effects of H3R signaling on C2C12 myocyte viability, apoptosis, and tumor necrosis factor alpha (TNFα)-induced NLRP3 inflammasome activation during striated myogenic differentiation at three time points (days 0, 3, and 6). Expression of Nlrp3, interleukin-1ß (IL-1ß), and myogenesis markers were determined. TNFα reduced overall viability of C2C12 cells, and exposure to TNFα induced apoptosis of cells at D6. Activation of H3R had no effect on viability or apoptosis, whereas inhibition of H3R increased TNFα-induced apoptosis. Stimulation of C2C12 cells with TNFα increased Nlrp3 mRNA expression at D3 and D6. Moreover, TNFα reduced the expression of myogenesis markers MyoD1, Myogenin, and Myosin-2 at D3 and D6. H3R attenuated TNFα-induced expression of Nlrp3 and further inhibited the myogenesis marker expression; while H3R -blockage enhanced the proinflammatory effects of TNFα and increased the myogenesis marker expression. TNFα-induced secretion of mature IL-1ß was dependent on the activation of the NLRP3 inflammasome, as shown by the reduced secretion of mature IL-1ß upon treatment of the cells with the small molecule inhibitor of the NLRP3 inflammasome (MCC950). The activation of H3R reduced TNFα-induced IL-1ß secretion, while the H3R blockage had an opposite effect. In conclusion, the modulation of H3R activity regulates the effects of TNFα on C2C12 myocyte differentiation and TNFα-induced activation of NLRP3 inflammasome. Thus, H3R signaling may represent a novel target for limiting postinjury muscle inflammation and muscle atrophy.

PTH1-34 inhibited TNF-α expression and antagonized TNF-α-induced MMP13 expression in MIO mice.

This study aims to investigate the effects and mechanisms of parathyroid hormone [1-34] (PTH1-34) on TNF-α-stimulated mice chondrocytes, as well as cartilage from a meniscus injury induced osteoarthritis (MIO) mice model. The C57BL/6J mice received medial meniscectomy, and then administrated with PTH1-34. The results showed that PTH1-34 administration decreased secondary allodynia and the pain-related transcripts. The IHC, ELISA, Micro-CT imaging and histopathology analysis revealed the significantly improved subchondral plate thickness and bone porosity, the reduced pro-inflammatory cytokines in serum and joint fluid. In vitro, mice chondrocyte was treated with TNF-α or co-cultured with synovial cells. The results showed that TNF-α markedly upregulated the MMP13 expression, and the ERK1/2, NF-κB or PI3K signaling pathway inhibitors could reverse the induction effect of TNF-α on expression of MMP13 in chondrocytes. PTH1-34 alone has no effect on the expression of MMP13 and NF-κB signaling pathways, but the PTH1-34 could reverse the induction effect of TNF-α on MMP13 expression and NF-κB signaling pathway activation in chondrocytes. In addition, PTH1-34 administration inhibited the expression of TNF-α and MMP13, and chondrocyte viability, while the PKA repressor reversed the effect of PTH1-34 in chondrocytes co-cultured with synovial cells. In conclusion, PTH1-34 has an obvious analgesic and anti-inflammatory effect, inhibits the matrix synthesis and alleviates the progression of osteoarthritis. In vitro, PTH1-34 inhibited TNF-α expression and antagonized TNF-α-induced MMP13 expression via the PKA pathway and the NF-κB signaling pathways, respectively.

ATF4-modified serum exosomes derived from osteoarthritic mice inhibit osteoarthritis by inducing autophagy.

Activating transcription factor 4 (ATF4) is critical for chondrocyte proliferation and bone formation. Exosomes are considered as promising gene-delivery vehicles for the treatment of osteoarthritis (OA). This study utilized the serum-derived exosomes from OA mice as the gene-delivery vehicles for ATF4 gene therapy and explored their therapeutic effects on OA. Meniscus injury-induced OA model was established by the excision of anterior part of medial meniscus in the right knee of C57BL/6J mice. Exosomes were isolated from serum samples of sham and OA mice, and were referred to as sham-Exo and OA-Exo, respectively. ATF4-overexpressing OA-Exo (ATF4-OA-Exo) was developed by introducing ATF4 mRNA into OA-Exo via electroporation. Four weeks after surgery, OA mice received intra-articular injections of sham-Exo, OA-Exo, and ATF4-OA-Exo, respectively. The results showed that intra-articular injection of ATF4-OA-Exo alleviated articular cartilage degeneration or damage and inflammatory response of OA mice. Autophagy was weakened in knee joint cartilage of OA mice, which was partially restored by intra-articular injection of ATF4-OA-Exo. Further in vitro assays revealed that ATF4-OA-Exo promoted chondrocyte autophagy and inhibited chondrocyte apoptosis in the TNF-α- or tunicamycin-treated chondrocytes. Together, ATF4-modified serum exosomes derived from OA mice protect cartilage and alleviate OA progression by inducing autophagy.

Erythropoietin enhances meniscal regeneration and prevents osteoarthritis formation in mice.

Osteoarthritis (OA) is a leading cause of pain and disability, and knee is the most commonly afflicted joint. Meniscal tear due to injury or degeneration is an established factor for OA pathogenesis. Previous studies have demonstrated that meniscectomy does not reduce the OA incidence. We hypothesized that enhancing meniscal regeneration may prevent OA formation and progression. We first investigated the developmental pattern of mouse meniscus. Knee joint samples were collected at embryonic stages as well as after birth for histological and immunohistochemical studies. The results showed that meniscal cells underwent active proliferation and apoptosis at embryonic day 19.5 and Day 1 after birth. Collagen I (Col-1) is a major type of matrix protein in matured meniscus. Meniscal cells isolated from 3-month-old mice were used to examine the effect of selected factors on the molecules related to cell proliferation, angiogenesis, inflammation, extracellular matrix proteins and matrix degradation enzymes. Overall assessment indicated that EPO had optimal effect on meniscal regeneration. An organ culture system of mouse meniscus was established to test the effect of EPO on in vitro cultured menisci. EPO upregulated the expression of Col-1, Col-2 and VEGF-A, and downregulated the expression of MMP-13. Finally, we established a mouse model of meniscus injury induced OA (MIO), and mice were subjected to PBS or EPO treatments. The results demonstrated that EPO enhanced meniscal repair and prevented OA formation. EPO may become an effective Disease Modifying Osteoarthritis Drug and may be used for early treatment for meniscal injury to prevent OA progression.

The pathogenesis and treatment in antineutrophil cytoplasmic antibody associated vasculitis.

Anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV) is a systemic autoimmune disease characterized by leukocytoclastic inflammation of small blood vessels. Commonly detected autoantibodies include anti-protease 3 (PR3) and anti-myeloperoxidase (MPO). Although cell necrosis plays an important role in the production of autoantibodies and the pathogenesis of AAV, the correlation between their titers and disease activity remains elusive. As improved detection techniques facilitate early diagnosis, a satisfactory efficacy can be achieved in patients with mild to medium severe AAV treated with glucocorticoids and immunosuppressants. However, resistant and relapsing AAV, sometimes life-threatening, do exist in clinical practice. In-depth understanding of pathogenesis of AAV may lend novel insight into the mechanism responsible for its formation and help find effective targeted therapies for refractory patients.