Mesenchymal stem cells-derived extracellular vesicles ameliorate lupus nephritis by regulating T and B cell responses.

BACKGROUND: Human umbilical cord mesenchymal stem cells-derived extracellular vesicles (hUCMSC-EVs) have potent immunomodulatory properties similar to parent cells. This study investigated the therapeutic effects and immunomodulatory mechanisms of hUCMSC-EVs in an experimental lupus nephritis model. METHODS: The hUCMSC-EVs were isolated by using differential ultracentrifugation. In vivo, the therapeutic effects of hUCMSC-EVs in lupus-prone MRL/lpr mice were investigated, and the mechanisms of treatment were explored according to the abnormal T and B cell responses among both the spleen and kidney. RESULTS: MRL/lpr mice treated with hUCMSC-EVs reduced proteinuria extent, serum creatinine and renal pathological damage; decreased splenic index and serum anti-dsDNA IgG level; and improved survival rate. hUCMSC-EVs lowered the percentage of T helper (Th)1 cells, double-negative T (DNT) cells, and plasma cells among splenocytes; inhibited the infiltration of Th17 cells but promoted regulatory T (Treg) cells in the kidney, followed by a reduction in pro-inflammatory cytokine levels(IFN-γ, IL-2, IL-6, IL-21, and IL-17 A). In addition, hUCMSC-EVs inhibited the activation of STAT3 and down-regulated IL-17 A protein levels in the kidney. CONCLUSION: The results of this study demonstrated that hUCMSC-EVs had therapeutic effects on experimental lupus nephritis (LN) by regulating Th1/Th17/Treg imbalance and inhibiting DNT and plasma cells. Additionally, hUCMSC-EVs inhibited Th17 cell differentiation in kidney by regulating the IL-6/STAT3/IL-17 signal pathway, which might be an important mechanism for alleviating renal injury. Taken together, we demonstrated that hUCMSC-EVs regulating T and B cell immune responses might represent a novel mechanism of hUCMSCs in treating LN, thus providing a new strategy for treating LN.

Therapeutic potential of MSCs and MSC-derived extracellular vesicles in immune thrombocytopenia.

Immune thrombocytopenia (ITP) is an acquired autoimmune disease involving a variety of immune cells and factors. Despite being a benign disease, it is still considered incurable due to its complex pathogenesis. Mesenchymal stem cells (MSCs), with low immunogenicity, pluripotent differentiation, and immunomodulatory ability, are widely used in a variety of autoimmune diseases. In recent years, impaired bone marrow mesenchymal stem cells (BMMSCs) were found to play an important role in the pathogenesis of ITP; and the therapeutic role of MSCs in ITP has also been supported by increasing evidence with encouraging efficacy. MSCs hold promise as a new approach to treat or even cure refractory ITP. Extracellular vesicles (EVs), as novel carriers in the "paracrine" mechanism of MSCs, are the focus of MSCs. Encouragingly, several studies suggested that EVs may perform similar functions as MSCs to treat ITP. This review summarized the role of MSCs in the pathophysiology and treatment of ITP.

Effects of a teaching mode combining SimBaby with standardized patients on medical students' attitudes toward communication skills.

OBJECTIVE: To evaluate the effect of a teaching mode combining SimBaby with standardized patients (SP) on medical students' attitudes toward communication skills (CS). METHODS: Forty 8-year medical program students majoring in clinical medicine were randomly divided into the SimBaby group (n = 20) and the SP + SimBaby group (n = 20). The Communication Skills Attitude Scale (CSAS) was used to evaluate medical students' attitudes toward CS learning. RESULTS: In the SimBaby and SP + SimBaby groups, there were no statistically significant differences in the Positive Attitude Subscale (PAS) and Negative Attitude Subscale (NAS) scores between males and females (p > 0.05). Compared to the SimBaby group, the SP + SimBaby group showed statistically significant differences in PAS, NAS, and the two dimensions of importance in medical context and learning (p < 0.05). There were no statistically significant differences between groups in the dimensions of excusing and overconfidence (p > 0.05). CONCLUSION: Compared with SimBaby alone, the SP + SimBaby teaching mode can improve medical students' attitude toward CS learning, suggesting that the organic integration of multiple simulation-based medical teaching methods plays an important role in the acquisition of CS.

MSC-EVs transferring mitochondria and related components: A new hope for the treatment of kidney disease.

Kidney disease is a serious hazard to human health. Acute or chronic renal disease will have a significant negative impact on the body's metabolism. The involvement of mitochondria in renal illness has received a lot of interest as research on kidney disease has advanced. Extracellular vesicles are gaining popularity as a means of intercellular communication in recent years. They have a close connection to both the nephropathy process and the intercellular transfer of mitochondria. The goal of this review is to present the extracellular vesicle transport mitochondria and its related biologically active molecules as new therapeutic options for the treatment of clinical kidney disease. This review focuses on the extracellular vesicles through the transfer of mitochondria and its related bioactive molecules, which affect mitochondrial energy metabolism, take part in immune regulation, and secrete outside the body.

Oral Realgar-Indigo Naturalis Formula Treatment for Acute Promyelocytic Leukemia in Children: A Randomized, Control Clinical Trial.

Objective: To analyze the efficacy, safety, and economy of RIF compared with intravenous arsenic trioxide (ATO) for the induction and consolidation therapy of pediatric APL. Materials and Methods: In this randomized control clinical trial (NCT02200978), children with newly diagnosed APL from June 2013 to December 2017 were randomly divided into RIF and ATO groups. The groups were treated with RIF or ATO in combination with all-trans retinoic acid (ARTA) and conventional chemotherapeutic drugs during induction and consolidation therapy. Results: Ninteen patients were enrolled, including eight in the RIF group and 11 in the ATO group. After induction therapy, the bone marrow morphologic complete remission (CR) rate, the median time to CR, and molecular remission (promyelocytic leukemia protein (PML)/retinoic acid receptor α (RARα) conversion) rates showed no significant differences between patients in the RIF versus ATO groups (100% vs. 100%, p=1.000; 22 vs. 24 days, p=0.395; 28.5% vs. 54.5%, p=0.367, resp.). After consolidation therapy, the molecular remission rate was 100% in both groups. At the end of more than two years of follow-up, the disease-free survival (DFS) rate was 100% in both groups. Conclusion: Oral RIF can achieve similar efficacy to intravenous ATO for APL in children with good safety, less toxicity, fewer side effects, and fewer inpatient days. Therefore, oral RIF can be used as an alternative to intravenous ATO for the treatment of APL in children.

Human umbilical cord mesenchymal stem cells derived extracellular vesicles regulate acquired immune response of lupus mouse in vitro.

Systemic lupus erythematosus (SLE) is an autoimmune disease involving multiple systems. Immunopathology believes that abnormal T cell function and excessive production of autoantibodies by B cells are involved in multi-organ damage. Human umbilical cord mesenchymal stem cells (hUCMSCs) therapies have endowed with promise in SLE, while the function of MSC-derived extracellular vesicles (MSC-EVs) was still unclear. Extracellular vesicles (EVs) are subcellular components secreted by a paracellular mechanism and are essentially a group of nanoparticles. EVs play a vital role in cell-to-cell communication by acting as biological transporters. New evidence has shown beneficial effects of MSC-EVs on autoimmune diseases, such as their immunomodulatory properties. In this study, we investigated whether hUCMSCs derived extracellular vesicles (hUCMSC-EVs) could regulate abnormal immune responses of T cells or B cells in SLE. We isolated splenic mononuclear cells from MRL/lpr mice, a classical animal model of SLE. PBS (Phosphate-buffered saline), 2 × 105 hUCMSCs, 25 µg/ml hUCMSC-EVs, 50 µg/ml hUCMSC-EVs were co-cultured with 2 × 106 activated splenic mononuclear cells for 3 days in vitro, respectively. The proportions of CD4+ T cell subsets, B cells and the concentrations of cytokines were detected. Both hUCMSCs and hUCMSC-EVs inhibited CD4+ T cells, increased the production of T helper (Th)17 cells, promoted the production of interleukin (IL)-17 and transforming growth factor beta1 (TGF-ß1) (P < 0.05), although they had no significant effects on Th1, Th2, T follicular helper (Tfh), regulatory T (Treg) cells and IL-10 (P > 0.05); only hUCMSCs inhibited CD19+ B cells, promoted the production of interferon-gamma (IFN-γ) and IL-4 (P < 0.05). hUCMSCs exert immunoregulatory effects on SLE at least partially through hUCMSC-EVs in vitro, therefore, hUCMSC-EVs play novel and potential regulator roles in SLE.

The Role of B1 Cells in Systemic Lupus Erythematosus.

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by multisystemic and multi-organ involvement, recurrent relapses and remissions, and the presence of large amounts of autoantibodies in the body as the main clinical features. The mechanisms involved in this disease are complex and remain poorly understood; however, they are generally believed to be related to genetic susceptibility factors, external stimulation of the body's immune dysfunction, and impaired immune regulation. The main immune disorders include the imbalance of T lymphocyte subsets, hyperfunction of B cells, production of large amounts of autoantibodies, and further deposition of immune complexes, which result in tissue damage. Among these, B cells play a major role as antibody-producing cells and have been studied extensively. B1 cells are a group of important innate-like immune cells, which participate in various innate and autoimmune processes. Yet the role of B1 cells in SLE remains unclear. In this review, we focus on the mechanism of B1 cells in SLE to provide new directions to explore the pathogenesis and treatment modalities of SLE.

Arthroscopic debridement combined with proximal fibular osteotomy in medial tibial articular genu osteoarthritis treatment: systematic review and meta-analysis.

BACKGROUND: We performed a systematic review and meta-analysis to evaluate the therapeutic effects of arthroscopic debridement and proximal fibular osteotomy (AD & PFO) on medial tibial articular genu osteoarthritis (MTAGO), so as to provide a theoretical reference for clinical surgical analgesia for patients. METHODS: We searched and screened randomized controlled trials (RCTs) focusing on AD & PFO on MTAGO surgical analgesia published before December 31, 2020 in English databases including PubMed, Embase, Medline, Ovid, Springer, and Web of Science. The Cochrane Handbook for Systematic Reviews of Intervention 5.0.2 was adopted for bias risk assessment, and Review Manager 5.3 was used to conduct the meta-analysis. RESULTS: Twelve eligible studies were included, involving 765 research subjects. The meta-analysis results indicated that, relative to control group, satisfaction was markedly increased [mean difference (MD) =3.10; 95% confidence interval (CI), (1.48 to 6.51); Z=3; P=0.003], adverse reactions were reduced [MD =0.33; 95% CI, (0.08 to 1.32); Z=1.56; P=0.12] the hospital special surgery (HSS) score was lower [MD =5.37; 95% CI, (3.18 to 7.55); Z=4.82; P<0.00001], the visual analogue scale (VAS) score decreased [MD =-1.68; 95% CI, (-2.22 to -1.13); Z=6.01; P<0.00001], and the Knee Society score (KSS) was reduced [MD =6.16; 95% CI, (3.85 to 8.47); Z=5.23; P<0.00001]. However, the difference in the femoro-tibial (FT) angle between the control and study groups was not statistically considerable [MD =0.14; 95% CI, (-6.22 to 6.49); Z=0.04; P=0.97]. DISCUSSION: The combined adoption of AD & PFO for MTAGO surgical analgesia can reduce the HSS, KSS, and VAS scores of patients. The postoperative analgesia effect is good, and effectively reduces pain and adverse reactions in patients. Thus, it is suitable for analgesia in MTAGO.

Management and Clinical Outcome of Posterior Reversible Encephalopathy Syndrome in Pediatric Oncologic/Hematologic Diseases: A PRES Subgroup Analysis With a Large Sample Size.

This study investigated the management and clinical outcomes along with associated factors of posterior reversible encephalopathy syndrome (PRES) in childhood hematologic/oncologic diseases. We present data from children with hematologic/oncologic diseases who developed PRES after treatment of the primary disease with chemotherapy and hematopoietic stem cell transplantation (HSCT) at 3 medical centers in Changsha, China from 2015 to 2020, and review all previously reported cases with the aim of determining whether this neurologic manifestation affects the disease prognosis. In the clinical cohort of 58 PRES patients, hypertension [pooled odds ratio (OR) = 4.941, 95% confidence interval (CI): 1.390, 17.570; P = 0.001] and blood transfusion (OR = 14.259, 95% CI: 3.273, 62.131; P = 0.001) were significantly associated with PRES. Elevated platelet (OR = 0.988, 95% CI: 0.982, 0.995; P < 0.001), hemoglobin (OR = 0.924, 95% CI: 0.890, 0.995; P < 0.001), and blood sodium (OR = 0.905, 95% CI: 0.860, 0.953; P < 0.001), potassium (OR = 0.599, 95% CI: 0.360, 0.995; P = 0.048), and magnesium (OR = 0.093, 95% CI: 0.016, 0.539; P = 0.008) were protective factors against PRES. Data for 440 pediatric PRES patients with hematologic/oncologic diseases in 21 articles retrieved from PubMed, Web of Science, and Embase databases and the 20 PRES patients from our study were analyzed. The median age at presentation was 7.9 years. The most common primary diagnosis was leukemia (62.3%), followed by solid tumor (7.7%) and lymphoma (7.5%). Most patients (65.0%) received chemotherapy, including non-induction (55.2%) and induction (44.8%) regimens; and 86.5% used corticosteroids before the onset of PRES. Although 21.0% of patients died during follow-up, in most cases (93.2%) this was not attributable to PRES but to severe infection (27.3%), underlying disease (26.1%), graft-vs.-host disease (14.8%), multiple organ dysfunction syndrome (8.0%), and respiratory failure (3.4%). PRES was more common with HSCT compared to chemotherapy and had a nearly 2 times higher mortality rate in patients with oncologic/hematologic diseases than in those with other types of disease. Monitoring neurologic signs and symptoms in the former group is therefore critical for ensuring good clinical outcomes following treatment of the primary malignancy.

Pharmacological and non-pharmacological interventions for osteoporosis: A protocol for an overview with an evidence map and a network meta-analysis of trials.

BACKGROUND: Osteoporosis is a common bone disease that has a significant social and economic effect. Many meta-analyses of pharmacological and non-pharmacological treatments for osteoporosis have been reported, but the findings may be contradictory, and both the reporting and methodological quality remain unknown. As a result, an overview that includes a network meta-analysis was proposed to address these issues. METHODS: The Cochrane library, PubMed, Embase, CBM, and CNKI databases will be systematically searched for meta-analyses of osteoporosis interventions from inception to May 2021. In order to evaluate the reporting and methodological quality of each included meta-analysis, Preferred Reporting Items for Systematic Review and Meta-analysis 2020 (PRISMA-2020), and A MeaSurement Tool to Assess systematic Reviews 2 (AMSTAR-2) will be used. For the assessment of the relative efficacy and safety of treatments reported in the randomized controlled trials included in the meta-analyses identified by the overview, a Bayesian network meta-analysis will be carried out. The odds ratio and standard mean difference with their 95% credible intervals will be used to present the binary and continuous outcomes, respectively, and the Grading of Recommendations Assessment, Development and Evaluation method will be used to determine the certainty of the evidence through Confidence In Network Meta-Analysis. Data analysis will be performed using WinBUGS, R, and Stata, with a 2-sided P < .05 considered as statistically significant. RESULTS: The findings of this overview, which includes a network meta-analysis, will be submitted to a peer-reviewed journal for publication. CONCLUSION: An overview with network meta-analysis will provide evidence on the efficacy and safety of pharmacological and non-pharmacological interventions for osteoporosis, while also identifying the flaws in previously published meta-analyses. All of these results may be used to improve clinical decision-making and future studies. INPLASY REGISTRATION NUMBER: INPLASY202150022.

Natural Killer Cell-Derived Extracellular Vesicles: Novel Players in Cancer Immunotherapy.

Natural killer (NK) cells are critical components of host innate immunity and function as the first line of defense against tumors and viral infection. There is increasing evidence that extracellular vesicles (EVs) are involved in the antitumor activity of NK cells. NK cell-derived EVs (NKEVs) carrying cargo such as cytotoxic proteins, microRNAs, and cytokines employ multiple mechanisms to kill tumor cells, but also exhibit immunomodulatory activity by stimulating other immune cells. Several studies have reported that NKEVs can reverse immune suppression under tolerogenic conditions and contribute to NK-mediated immune surveillance against tumors. Thus, NKEVs are a promising tool for cancer immunotherapy. In this review, we describe the biological effects and potential applications of NKEVs in antitumor immunity.

[Epidemiological and clinical features of children with mild coronavirus disease 2019].

OBJECTIVE: To study the epidemiological and clinical features of children with mild coronavirus disease 2019 (COVID-19). METHODS: The children who were diagnosed with mild COVID-19 in the Wuchang Shelter Hospital in Wuhan from February 5 to March 10, 2020 were enrolled as subjects. The clinical, laboratory, and lung imaging data were collected during hospitalization and isolation. This was a retrospective single-center case series analysis. RESULTS: A total of 1 124 patients with mild COVID-19 were admitted from February 5 to March 10, 2020, including 13 children (1.16%). All the 13 children (7 boys and 6 girls) were residents of Wuhan in China, with a median age of 16 years (range: 10-18 years). Of all the 13 children, 9(69%) were from family clusters of COVID-19 and 4(31%) had unknown sources of infection. The mean time from exposure to onset was 6.8 days (range: 2-13 days) in 9 children with a definite history of exposure. There were 6 symptomatic children with the main manifestations of fever, cough, weakness, and myalgia, and the mean time from onset to hospitalization was 9.2 days. Of all the 13 children, 7(54%) were asymptomatic with positive nucleic acid test of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). There were 4 children (31%) with abnormal lung CT findings, mainly patchy shadows or ground-glass opacities in the lung field, and 6 children (46%) had no symptoms with normal lung CT findings. All children had normal routine blood test results and C-reactive protein levels. Eight children underwent SARS-CoV-2 IgM and IgG tests at least once, among whom 6 had negative SARS-CoV-2 IgM but positive IgG, and 2 underwent SARS-CoV-2 IgM and IgG tests twice and had negative results. Of all the 13 children, 11(85%) had negative results of two SARS-CoV-2 nucleic acid tests during hospitalization and were discharged, and 2(15%) had positive results of four SARS-CoV-2 nucleic acid tests and were transferred to another hospital and lost to follow-up. Among the 11 children who were followed up, 1 had positive results of two SARS-CoV-2 nucleic acid tests at the isolation point, and 10 had negative results. The mean hospital stay was 10.9 days for the 13 children. Eleven children recovered during follow-up, with good living and learning conditions. CONCLUSIONS: Children with mild COVID-19 often have an uncertain history of exposure and may not have any clinical symptoms. Etiological diagnosis is more important than clinical diagnosis. The disappearance of clinical manifestations may not parallel with the result of SARS-CoV-2 nucleic acid test. SARS-CoV-2 has a long detoxification time, and there may be recurrent cases of SARS-CoV-2 positivity. Further studies are needed to investigate the production patterns of SARS-CoV-2 IgM and IgG and their effect on the body.

Analysis of Risk Factors Associated With Poor Outcome in Posterior Reversible Encephalopathy Syndrome After Treatment in Children: Systematic Review and Meta-Analysis.

Objective: Chemotherapy and hematopoietic stem cell transplantation (HSCT) play important roles in clinical etiology, symptoms, signs, imaging findings, and biochemical parameters for inducing posterior reversible encephalopathy syndrome (PRES) in pediatric oncologic diseases. We aimed to evaluate various risk factors of pediatric oncologic diseases after conducting chemotherapy and HSCT to induce PRES for predicting the clinical prognosis frequency. Methods: The literature was performed on PubMed, Web of Science, and Embase databases to recognize the qualified studies. The odds ratios (ORs) of related risk factors and their corresponding 95% confidence intervals (CIs) were used to compute the pooled assessments of the outcomes. Results: Six studies were included in the meta-analysis, involving 828 records. The risk of female children has a significantly higher incidence than male children in oncologic age groups of PRES. Children over the age of 10 years old in oncologic age groups develop a significantly increased risk of PRES. Acute graft-versus-host disease (GVHD) has a significant promotion effect on the occurrence of PRES. Hypertension can promote the occurrence of PRES in children. The risk of PRES in immunodeficient children increases significantly. Children with sickle cell disease (SCD) have a significantly increased risk of PRES. The risk of PRES in children with T-cell leukemia rises considerably. The central nervous system (CNS) leukemia/involvement has a significant role in promoting the occurrence of PRES in children. The pooled OR for the factors male, ≥ 10 years old of age, acute GVHD, hypertension, immunodeficiency, SCD, T-cell leukemia, CNS leukemia/involvement was 0.66 (95% CI: 0.58, 0.76; P < 0.00001), 2.06 (95% CI: 1.23, 3.43; P < 0.006), 1.32 (95% CI: 1.14, 1.53; P < 0.0003), 8.84 (95% CI: 7.57, 10.32; P < 0.00001), 2.72 (95% CI: 1.81, 4.08; P < 0.00001), 2.87 (95% CI: 2.15, 3.83; P < 0.00001), 2.84 (95% CI: 1.65, 4.88; P < 0.0002), and 3.13 (95% CI: 1.43, 6.84; P < 0.004), respectively. Conclusions: The result of this meta-analysis suggests that female children, age over 10 years old, acute GVHD, hypertension, immunodeficiency, SCD, T-cell leukemia, and CNS leukemia/involvement are likely to have the poor outcome in pediatric oncologic/hematologic diseases in PRES.

[Roles of the public-facility-turned temporary hospital in prevention and control of coronavirus disease 2019 in Wuhan, China and clinical experience in the hospital].

Since the outbreak of coronavirus disease 2019 (COVID-19) in Wuhan, China, the public-facility-turned temporary hospital (PFTH) has played an important role in preventing the spread of the epidemic. Wuchang PFTH is the first one to put into clinical practice and the last one suspended in Wuhan. The National Emergency Medical Rescue Team of the Second Xiangya Hospital of Central South University, together with other 13 medical teams (841 medical staff in total), have fulfilled the task for the treatment of non-severe COVID-19 patients, without any medical staff infected. The first author of the article was the only pediatrician working in the Wuchang PFTH. The author describes and summarizes the features/functions, management/operations, and advantages/challenges of the PFTH, in order to provide reference for medical institutions and relevant departments to deal with public health emergencies.

Immunoregulatory Effects of Mitochondria Transferred by Extracellular Vesicles.

Mitochondria participate in immune regulation through various mechanisms, such as changes in the mitochondrial dynamics, as metabolic mediators of the tricarboxylic acid cycle, by the production of reactive oxygen species, and mitochondrial DNA damage, among others. In recent years, studies have shown that extracellular vesicles are widely involved in intercellular communication and exert important effects on immune regulation. Recently, the immunoregulatory effects of mitochondria from extracellular vesicles have gained increasing attention. In this article, we review the mechanisms by which mitochondria participate in immune regulation and exert immunoregulatory effects upon delivery by extracellular vesicles. We also focus on the influence of the immunoregulatory effects of mitochondria from extracellular vesicles to further shed light on the underlying mechanisms.