Conserved moonlighting protein pyruvate dehydrogenase induces robust protection against Staphylococcus aureus infection.

Developing an effective Staphylococcus aureus (S. aureus) vaccine has been a challenging endeavor, as demonstrated by numerous failed clinical trials over the years. In this study, we formulated a vaccine containing a highly conserved moonlighting protein, the pyruvate dehydrogenase complex E2 subunit (PDHC), and showed that it induced strong protective immunity against epidemiologically relevant staphylococcal strains in various murine disease models. While antibody responses contributed to bacterial control, they were not essential for protective immunity in the bloodstream infection model. Conversely, vaccine-induced systemic immunity relied on γδ T cells. It has been suggested that prior S. aureus exposure may contribute to the reduction of vaccine efficacy. However, PDHC-induced protective immunity still facilitated bacterial clearance in mice previously exposed to S. aureus. Collectively, our findings indicate that PDHC is a promising serotype-independent vaccine candidate effective against both methicillin-sensitive and methicillin-resistant S. aureus isolates.

Effect of allogeneic hematopoietic stem cell transplantation for chronic granulomatous disease in children: A multicentre, retrospective cohort study in China.

Chronic granulomatous disease (CGD) in children is a rare primary immunodeficiency disorder that can lead to life-threatening infections and inflammatory complications. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is increasingly being used to treat severe CGD in children. We conducted a multicenter retrospective analysis of children with CGD who were treated with allo-HSCT at four pediatric hematopoietic stem cell transplant centers in China from September 2005 to December 2019. The study included a total of 171 patients (169 males and 2 females). The median age at the time of transplantation was 6.1 (0-16.4) years. Among them, 154 patients had X-linked recessive inheritance caused by CYBB gene mutations, 12 patients were autosomal recessive, 1 patient had DNAH11 and HYDIN gene mutations, and 4 patients had no gene mutations. The median follow-up period was 36.3 (1.9-79) months. All participating patients were applied to myeloablative conditioning (MAC) regimens. The rates of OS, EFS, and GEFS within three years were 87.5%, 85.3%, and 75.2%, respectively. The total graft failure and the total mortality rate were 5.3% and 11.1%. The cumulative incidence of acute GVHD was 53.8% and the incidence of chronic GVHD was 12.9%, The incidence of chronic GVHD was higher for patients who received unrelated donor cord blood stem cell transplantation (UD-CB) (P = 0.001). Chronic GVHD and coinfections are the risk factors for OS and EFS in patients with CGD after receiving allo-HSCT. UD-CB is a risk factor for EFS and the presence of pneumonia before transplantation is a risk factor for OS. In conclusion, through this study, we have demonstrated that allo-HSCT has excellent efficacy in the treatment of CGD in children, especially, RD-haplo is associated with a lower rate of graft failure incidence and mortality than the treatment modalities of other donor type. Therefore, allo-HSCT is strongly recommended when a well-matched donor is available. If a well-matched donor is not available, the HLA-mismatched donor should be carefully evaluated, and the conditioning regimen modified accordingly.

Successful Immune Reconstitution in a Patient with a TYK2 Deficiency after Allogeneic Stem Cell Transplantation from Unrelated Donors.

A boy with primary immunodeficiency, caused by a tyrosine kinase 2 (TYK2) mutation, presented with immune defects and a lifelong history of severe infections. Our aim was to determine whether allogeneic hematopoietic stem cell transplantation (HSCT) could restore the patient's immune defenses and reduce susceptibility to infection. In the absence of a suitable HLA-matched blood relative to act as a donor, the patient received an allogeneic HSCT from unrelated donors. The patient's clinical data were analyzed in the Children's Hospital of Chongqing Medical University (Chongqing, China) before transplantation and during the 4-year follow-up period using a combination of western blotting (e.g., TYK2 and STAT levels), qRT-PCR (e.g., T cell receptor rearrangement excision circles, kappa deletion element recombination circles, and TYK2 transcript levels), and flow cytometry (e.g., lymphocyte subpopulations and CD107α secretion). We found that HSCT significantly reduced the incidence of severe infections, restored normal TKY2 levels, and reversed defects such as impaired JAK/STAT signaling in response to interferon-α or interleukin-10 treatment. Although the patient did not develop acute graft-versus-host disease (GVHD) after transplantation, he did experience chronic GVHD symptoms in a number of organs, which were effectively managed. Our findings suggest that HSCT is a feasible strategy for reconstituting the immune system in TYK2-deficient patients; however, the factors associated with GVHD and autoimmune thyroiditis development in TYK2-deficient patients undergoing HSCT warrant further investigation.

Risk factors and survival outcomes in children with early cardiotoxicity after allogeneic hematopoietic stem cell transplantation.

Cardiotoxicity in children is a potentially fatal complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT); therefore, early identification of risk factors can improve patient prognosis. However, there are few data on the clinical characteristics of early-stage cardiotoxicity in children after allo-HSCT. We conducted a retrospective single-center study of pediatric patients who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) between January 2016 and December 2022 at the Children's Hospital Affiliated with Chongqing Medical University to evaluate the clinical characteristics of early cardiac events (ECEs) after allo-HSCT and their impact on survival outcomes. We enrolled 444 patients who underwent allo-HSCT-304 males (68%) and 140 females (32%)-with a median age of 3.3 years (1.8-6.5 years) at transplantation. We found that 73 patients (16.4%) had ECEs after allo-HSCT. The ECEs included valvular disease (n = 46), pericardial effusion (n = 38), arrhythmia (n = 9), heart failure (n = 16), and dilated cardiomyopathy (n = 1). Female sex, age ≥ 6 years, body mass index (BMI) < 16 kg/m2 and HLA-type mismatches were risk factors for ECEs. We designed a stratified cardiac risk score that included these risk factors, and the higher the score was, the greater the cumulative incidence of ECEs. The occurrence of an ECE was closely associated with a lower overall survival (OS) rate and greater nonrelapse mortality (NRM). In addition, stratified analysis based on the number of combined ECEs showed that the greater the number of combined ECEs was, the more significant the negative impact on OS rates.

The distribution of intestinal flora after hematopoietic stem cell transplantation in children.

BACKGROUND: This prospective study aimed to comprehensively understand the changes in intestinal flora at different stages after hematopoietic stem cell transplantation (HSCT) in pediatric patients and to analyze the effect of intestinal flora on acute graft versus host disease (aGVHD), especially on gastrointestinal graft versus host disease (GI GVHD). METHODS: A total of 32 children with primary diseases of primary immunodeficiency disease (PID) and thalassemia were included. 16S sequencing was used to characterize the microbiota layout at three time points peri-transplant including pre-transplant, Day +3, and Day +30. RESULTS: By comparing the intestinal flora of children with GI GVHD and those without GI GVHD, it suggests that in children with GI GVHD, the distribution of intestinal flora after transplantation was more variable and more chaotic (chao1 index, Friedman test, p = .029). Besides, Veillonella and Ruminococcaceae were more abundant before transplantation, Bifidobacteriaceae and Bacillales were more abundant after transplantation. Comparing children with PID and thalassemia, it was found that the destruction of gut microbiota diversity was more significant in children with thalassemia after transplantation. The comparison of children with 0-I° aGVHD and II-III° aGVHD indicates that children with II-III° aGVHD had more Bilophila before transplantation than children with 0-I° aGVHD. Additionally, exploratory analyses to evaluate correlations between clinical characteristics (medications, immune cell recovery, etc.) and microbiome features were also performed. CONCLUSIONS: This study has synthetically shown the distribution of intestinal flora after allo-HSCT, and some characteristic bacteria at different stages that may serve as potential biomarkers were screened out additionally, perhaps providing clues for the prevention and treatment of the disease.

New Analogues of Amides and Quinolinones Produced by Streptomyces sp. YIM S01983.

Streptomide (1), a new amide analogue, streptomynone (2), a new quinolinone, and ten known compounds including three aliphatic acids (3-5), two amides (6-7), four cyclic dipeptides (8-11), and an adenosine (12) were isolated from the fermentation broth of Streptomyces sp. YIM S01983 isolated from a sediment sample collected in Bendong Village, Huadong Town, Chuxiong, China. Their structures were determined by analysis of the 1D/2D-NMR and HR-ESI-MS spectra. Compound 12 presented weak antimicrobial activities against Candida albicans and Aligenes faecalis (MIC=64 µg/mL). Compounds 7 and 12 showed weak cytotoxic activity against MHCC97H.

[Risk factors for recurrence of childhood acute lymphoblastic leukemia after treatment with the Chinese Children's Cancer Group ALL-2015 protocol]. / CCCG-ALL-2015æ–¹æ¡ˆæ²»ç–—å„¿ç«¥æ€¥æ€§æ·‹å·´ç»†èƒžç™½è¡€ç— å¤å‘çš„å±é™©å› ç´ åˆ†æž.

OBJECTIVES: To investigate the cumulative incidence of recurrence (CIR) in children with acute lymphoblastic leukemia (ALL) after treatment with the Chinese Children's Cancer Group ALL-2015 (CCCG-ALL-2015) protocol and the risk factors for recurrence. METHODS: A retrospective analysis was conducted on the clinical data of 852 children who were treated with the CCCG-ALL-2015 protocol from January 2015 to December 2019. CIR was calculated, and the risk factors for the recurrence of B-lineage acute lymphoblastic leukemia (B-ALL) were analyzed. RESULTS: Among the 852 children with ALL, 146 (17.1%) experienced recurrence, with an 8-year CIR of 19.8%±1.6%. There was no significant difference in 8-year CIR between the B-ALL group and the acute T lymphocyte leukemia group (P>0.05). For the 146 children with recurrence, recurrence was mainly observed in the very early stage (n=62, 42.5%) and the early stage (n=46, 31.5%), and there were 42 children with bone marrow recurrence alone (28.8%) in the very early stage and 27 children with bone marrow recurrence alone (18.5%) in the early stage. The Cox proportional-hazards regression model analysis showed that positive MLLr fusion gene (HR=4.177, 95%CI: 2.086-8.364, P<0.001) and minimal residual disease≥0.01% on day 46 (HR=2.013, 95%CI: 1.163-3.483, P=0.012) were independent risk factors for recurrence in children with B-ALL after treatment with the CCCG-ALL-2015 protocol. CONCLUSIONS: There is still a relatively high recurrence rate in children with ALL after treatment with the CCCG-ALL-2015 protocol, mainly bone marrow recurrence alone in the very early stage and the early stage, and minimal residual disease≥0.01% on day 46 and positive MLLr fusion gene are closely associated with the recurrence of B-ALL.

IL-1 Transcriptional Responses to Lipopolysaccharides Are Regulated by a Complex of RNA Binding Proteins.

The IL1A and IL1B genes lie in close proximity on chromosome 2 near the gene for their natural inhibitor, IL1RN Despite diverse functions, they are all three inducible through TLR4 signaling but with distinct kinetics. This study analyzed transcriptional induction kinetics, chromosome looping, and enhancer RNA production to understand the distinct regulation of these three genes in human cells. IL1A, IL1B, and IL1RN were rapidly induced after stimulation with LPS; however, IL1B mRNA production was less inhibitable by iBET151, suggesting it does not use pause-release regulation. Surprisingly, chromatin looping contacts between IL1A and IL1B were highly intermingled, although those of IL1RN were distinct, and we focused on comparing IL1A and IL1B transcriptional pathways. Our studies demonstrated that enhancer RNAs were produced from a subset of the regulatory regions, that they were critical for production of the mRNAs, and that they bound a diverse array of RNA binding proteins, including p300 but not CBP. We, furthermore, demonstrated that recruitment of p300 was dependent on MAPKs. Integrator is another RNA binding protein recruited to the promoters and enhancers, and its recruitment was more dependent on NF-κB than MAPKs. We found that integrator and NELF, an RNA polymerase II pausing protein, were associated with RNA in a manner that facilitated interaction. We conclude that IL1A and IL1B share many regulatory contacts, signaling pathways, and interactions with enhancer RNAs. A complex of protein interactions with enhancer RNAs emphasize the role of enhancer RNAs and the overall structural aspects of transcriptional regulation.

[Clinical effect of allogeneic hematopoietic stem cell transplantation in children with hyper-IgM syndrome]. / å¼‚åŸºå› é€ è¡€å¹²ç»†èƒžç§»æ¤æ²»ç–—å„¿ç«¥é«˜IgM综合征的临床分析.

OBJECTIVES: To evaluate the clinical effect of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in children with hyper-IgM syndrome (HIGM). METHODS: A retrospective analysis was performed on the medical data of 17 children with HIGM who received allo-HSCT. The Kaplan Meier method was used for the survival analysis of the children with HIGM after allo-HSCT. RESULTS: After allo-HSCT, 16 children were diagnosed with sepsis; 14 tested positive for virus within 100 days after allo-HSCT, among whom 11 were positive for Epstein-Barr virus, 7 were positive for cytomegalovirus, and 2 were positive for JC virus; 9 children were found to have invasive fungal disease. There were 6 children with acute graft-versus-host disease and 3 children with chronic graft-versus-host disease. The median follow-up time was about 2 years, and 3 children died in the early stage after allo-HSCT. The children had an overall survival (OS) rate of 82.35%, an event-free survival (EFS) rate of 70.59%, and a disease-free survival (DFS) rate of 76.47%. The univariate analysis showed that the children receiving HLA-matched allo-HSCT had a significantly higher EFS rate than those receiving HLA-mismatched allo-HSCT (P=0.019) and that the children receiving HLA-matched unrelated allo-HSCT had significantly higher OS, EFS, and DFS rates than those receiving HLA-mismatched unrelated allo-HSCT (P<0.05). Compared with the children with fungal infection after allo-HSCT, the children without fungal infection had significantly higher EFS rate (P=0.02) and DFS rate (P=0.04). CONCLUSIONS: Allo-HSCT is an effective treatment method for children with HIGM. HLA-matched allo-HSCT and active prevention and treatment of fungal infection and opportunistic infection may help to improve the prognosis of such children.

Diabetes mellitus exacerbates experimental autoimmune myasthenia gravis via modulating both adaptive and innate immunity.

BACKGROUND: Diabetes mellitus (DM) is a common concomitant disease of late-onset myasthenia gravis (MG). However, the impacts of DM on the progression of late-onset MG were unclear. METHODS: In this study, we examined the immune response in experimental autoimmune myasthenia gravis (EAMG) rats with DM or not. The phenotype and function of the spleen and lymph nodes were determined by flow cytometry. The serum antibodies, Tfh cells, and germinal center B cells were determined by ELISA and flow cytometry. The roles of advanced glycation end products (AGEs) in regulating Tfh cells were further explored in vitro by co-culture assays. RESULTS: Our results indicated clinical scores of EAMG rats were worse in diabetes rats compared to control, which was due to the increased production of anti-R97-116 antibody and antibody-secreting cells. Furthermore, diabetes induced a significant upregulation of Tfh cells and the subtypes of Tfh1 and Tfh17 cells to provide assistance for antibody production. The total percentages of B cells were increased with an activated statue of improved expression of costimulatory molecules CD80 and CD86. We found CD4+ T-cell differentiation was shifted from Treg cells towards Th1/Th17 in the DM+EAMG group compared to the EAMG group. In addition, in innate immunity, diabetic EAMG rats displayed more CXCR5 expression on NK cells. However, the expression of CXCR5 on NKT cells was down-regulated with the increased percentages of NKT cells in the DM+EAMG group. Ex vivo studies further indicated that Tfh cells were upregulated by AGEs instead of hyperglycemia. The upregulation was mediated by the existence of B cells, the mechanism of which might be attributed the elevated molecule CD40 on B cells. CONCLUSIONS: Diabetes promoted both adaptive and innate immunity and exacerbated clinical symptoms in EAMG rats. Considering the effect of diabetes, therapy in reducing blood glucose levels in MG patients might improve clinical efficacy through suppressing the both innate and adaptive immune responses. Additional studies are needed to confirm the effect of glucose or AGEs reduction to seek treatment for MG.

Mucosal Invariant T cells are Diminished in Very Early-Onset Inflammatory Bowel Disease.

OBJECTIVES: Very early-onset inflammatory bowel disease (VEO-IBD) arises in children less than 6 years old, a critical time for immunologic development and maturation of the intestinal microbiome. Non-conventional lymphocytes, defined here as mucosal-associated invariant T cells and innate lymphocytes, require microbial products for either development or expansion, aspects that could be altered in very early-onset inflammatory bowel disease. Our objective was to define conventional leukocyte and non-conventional lymphocyte populations in controls and patients using multiparameter flow cytometry to test the hypothesis that their frequencies would be altered in a chronic inflammatory state associated with significant dysbiosis. METHODS: Multiparameter flow cytometry was used in a control cohort of 105 subjects to define age-effects, not previously comprehensively examined for these cell types in humans. Differences were defined between 263 unique age-matched patients with VEO-IBD and 105 controls using Student t-test. Subjects were divided into two age groups at the time of sampling to control for age-related changes in immune composition. RESULTS: Intermediate monocytes were consistently decreased in patients with VEO-IBD compared to controls. Mucosal-associated invariant T cells were significantly lower in patients with long-standing disease. Levels were less than half of those seen in the age-matched control cohort. The innate lymphoid cells type 2 population was expanded in the youngest patients. CONCLUSION: Mucosal-associated invariant T cells are diminished years after presentation with inflammatory bowel disease. This durable effect of early life intestinal inflammation may have long-term consequences. Diminished mucosal-associated invariant T cells could impact host defense of intestinal infections.

Application of high-throughput sequencing for hereditary thrombocytopenia in southwestern China.

BACKGROUND: The aim of this study was to design and analyze the applicability of a 21-gene high-throughput sequencing (HTS) panel in the molecular diagnosis of patients with hereditary thrombocytopenia (HT). METHODS: A custom target enrichment library was designed to capture 21 genes known to be associated with HTs. Twenty-four patients with an HT phenotype were studied using this technology. RESULTS: One pathogenic variant on the MYH9 gene and one likely pathogenic variant on the ABCG8 gene previously known to cause HTs were identified. Additionally, 3 previously reported variants affecting WAS, ADAMTS13, and GP1BA were detected, and 9 novel variants affecting FLNA, ITGB3, NBEAL2, MYH9, VWF, and ANKRD26 genes were identified. The 12 variants were classified to be of uncertain significance. CONCLUSION: Our results demonstrate that HTS is an accurate and reliable method of pre-screening patients for variants in known HT-causing genes. With the advantage of distinguishing HT from immune thrombocytopenia, HTS could play a key role in improving the clinical management of patients.

Antimicrobial Natural Products Produced by Soil-Derived Fungus Penicillium cremeogriseum W1-1.

Ten compounds (1-10) were obtained from soil-derived Penicillium cremeogriseum W1-1 with the antimicrobial guided isolation procedure. Among them, 4 presented broad-spectrum antimicrobial activities and its preliminary mechanisms were evaluated. Compound 4 showed growth inhibition on drug-resistant pathogenic strains Escherichia coli and Candida albicans with post-contact effect (PCE), changed the morphology and membrane structure, killed cells with leakage, inhibited the growth of C. albicans by eradicating biofilms. Interestingly, the fraction containing 4 presented in vivo anti-pathogenic activities in mice, indicating this indole diterpenoid alkaloid could been used as potential antimicrobial agent.

Prognostic significance of measurable residual disease based on multiparameter flow cytometry in childhood acute myeloid leukemia. / åŸºäºŽæµå¼ç»†èƒžæœ¯çš„å¯æµ‹é‡æ®‹ç•™ç— å¯¹å„¿ç«¥æ€¥æ€§é«“ç³»ç™½è¡€ç— é¢„åŽæ„ä¹‰çš„å‰çž»æ€§ç ”ç©¶.

OBJECTIVES: To study the prognostic value of measurable residual disease (MRD) for childhood acute myeloid leukemia (AML) by analyzing MRD-guided risk stratification therapy. METHODS: A total of 93 children with AML were prospectively enrolled in this study. Chemotherapy with the 2015-AML-03 regimen was completed according to the risk stratification determined by genetic abnormality at initial diagnosis and MRD and bone marrow cytology after induction therapy I. Multiparameter flow cytometry was used to dynamically monitor MRD and analyze the prognostic effect of MRD on 3-year cumulative incidence of recurrence (CIR) rate, event-free survival (EFS) rate, and overall survival (OS) rate. RESULTS: The 93 children with AML had a 3-year CIR rate of 48%±6%, a median time to recurrence of 11 months (range 2-32 months), a 3-year OS rate of 65%±6%, and a 3-year EFS rate of 50%±5%. After induction therapy I and intensive therapy I, the MRD-positive children had a significantly higher 3-year CIR rate and significantly lower 3-year EFS and OS rates than the MRD-negative children (P<0.05). There were no significant differences in 3-year CIR, EFS, and OS rates between the MRD-positive children with a low risk at initial diagnosis and the MRD-negative children after adjustment of chemotherapy intensity (P>0.05). The multivariate analysis showed that positive MRD after intensive treatment I was a risk factor for 3-year OS rate in children with AML (P<0.05). CONCLUSIONS: MRD has predictive value for the prognosis of children with AML. Based on the MRD-guided risk stratification therapy, reasonable application of chemotherapy may improve the overall prognosis of children with AML.

Clinical features and prognosis of children with acute leukemias of ambiguous lineage under different diagnostic criteria. / ä¸åŒè¯Šæ–­æ ‡å‡†ä¸‹å„¿ç«¥æ€¥æ€§ä¸æ˜Žè°±ç³»ç™½è¡€ç— çš„ä¸´åºŠç‰¹ç‚¹å’Œé¢„åŽåˆ†æž.

OBJECTIVES: To study the clinical features and prognosis of children with acute leukemias of ambiguous lineage (ALAL) under different diagnostic criteria. METHODS: A retrospective analysis was performed on the medical data of 39 children with ALAL who were diagnosed and treated from December 2015 to December 2019. Among the 39 children, 34 received treatment. According to the diagnostic criteria for ALAL by World Health Organization and European Group for the Immunological Characterization of Leukemias, the 39 children were divided into two groups: ALAL group (n=28) and myeloid expression group (n=11). The clinical features, treatment, and prognosis were compared between the two groups. RESULTS: The 34 children receiving treatment had a 3-year event-free survival (EFS) rate of 75%±9% and an overall survival rate of 88%±6%. The children treated with acute myeloid leukemia (AML) protocol had a 3-year EFS rate of 33%±27%, those treated with acute lymphoblastic leukemia (ALL) protocol had a 3-year EFS rate of 78%±10%, and those who had no remission after induction with AML protocol and then received ALL protocol had a 3-year EFS rate of 100%±0% (P<0.05). The children with negative minimal residual disease (MRD) after induction therapy had a significantly higher 3-year EFS rate than those with positive MRD (96%±4% vs 38%±28%, P<0.05). Positive ETV6-RUNX1 was observed in the myeloid expression group, and positive BCR-ABL1, positive MLL-r, and hyperleukocytosis (white blood cell count ≥50×109/L) were observed in the ALAL group. There was no significant difference in the 3-year EFS rate between the myeloid expression and ALAL groups (100%±0% vs 66%±11%, P>0.05). CONCLUSIONS: ALL protocol has a better clinical effect than AML protocol in children with ALAL, and positive MRD after induction therapy suggests poor prognosis. Hyperleukocytosis and adverse genetic changes are not observed in children with myeloid expression, and such children tend to have a good prognosis, suggesting that we should be cautious to take it as ALAL in diagnosis and treatment.

CD8+ T-cell senescence and skewed lymphocyte subsets in young Dyskeratosis Congenita patients with PARN and DKC1 mutations.

BACKGROUND: Dyskeratosis congenita (DC) is a syndrome resulting from defective telomere maintenance. Immunodeficiency associated with DC can cause significant morbidity and lead to premature mortality, but the immunological characteristics and molecular hallmark of DC patients, especially young patients, have not been described in detail. METHODS: We summarize the clinical data of two juvenile patients with DC. Gene mutations were identified by whole-exome and direct sequencing. Swiss-PdbViewer was used to predict the pathogenicity of identified mutations. The relative telomere length was determined by QPCR, and a comprehensive analysis of lymphocyte subsets and CD57 expression was performed by flow cytometry. RESULTS: Both patients showed typical features of DC without severe infection. In addition, patient 1 (P1) was diagnosed with Hoyeraal-Hreidarsson syndrome due to cerebellar hypoplasia. Gene sequencing showed P1 had a compound heterozygous mutation (c.204G > T and c.178-245del) in PARN and P2 had a novel hemizygous mutation in DKC1 (c.1051A > G). Lymphocyte subset analysis showed B and NK cytopenia, an inverted CD4:CD8 ratio, and decreased naïve CD4 and CD8 cells. A significant increase in CD21low B cells and skewed numbers of helper T cells (Th), regulatory T cells (Treg), follicular regulatory T cells (Tfr), and follicular helper T cells (Tfh) were also detected. Short telomere lengths, increased CD57 expression, and an expansion of CD8 effector memory T cells re-expressing CD45RA (TEMRA) were also found in both patients. CONCLUSION: Unique immunologic abnormalities, CD8 T-cell senescence, and shortened telomere together as a hallmark occur in young DC patients before progression to severe disease.

CXCR5-negative natural killer cells ameliorate experimental autoimmune myasthenia gravis by suppressing follicular helper T cells.

BACKGROUND: Recent studies have demonstrated that natural killer (NK) cells can modulate other immune components and are involved in the development or progression of several autoimmune diseases. However, the roles and mechanisms of NK cells in regulating experimental autoimmune myasthenia gravis (EAMG) remained to be illustrated. METHODS: To address the function of NK cells in experimental autoimmune myasthenia gravis in vivo, EAMG rats were adoptively transferred with splenic NK cells. The serum antibodies, and splenic follicular helper T (Tfh) cells and germinal center B cells were determined by ELISA and flow cytometry. The roles of NK cells in regulating Tfh cells were further verified in vitro by co-culturing splenocytes or isolated T cells with NK cells. Moreover, the phenotype, localization, and function differences between different NK cell subtypes were determined by flow cytometry, immunofluorescence, and ex vivo co-culturation. RESULTS: In this study, we found that adoptive transfer of NK cells ameliorated EAMG symptoms by suppressing Tfh cells and germinal center B cells. Ex vivo studies indicated NK cells inhibited CD4+ T cells and Tfh cells by inducing the apoptosis of T cells. More importantly, NK cells could be divided into CXCR5- and CXCR5+ NK subtypes according to the expression of CXCR5 molecular. Compared with CXCR5- NK cells, which were mainly localized outside B cell zone, CXCR5+ NK were concentrated in the B cell zone and exhibited higher expression levels of IL-17 and ICOS, and lower expression level of CD27. Ex vivo studies indicated it was CXCR5- NK cells not CXCR5+ NK cells that suppressed CD4+ T cells and Tfh cells. Further analysis revealed that, compared with CXCR5- NK cells, CXCR5+ NK cells enhanced the ICOS expression of Tfh cells. CONCLUSIONS: These findings highlight the different roles of CXCR5- NK cells and CXCR5+ NK cells. It was CXCR5- NK cells but not CXCR5+ NK cells that suppressed Tfh cells and inhibited the autoimmune response in EAMG models.

Correction to: Exosomes derived from atorvastatin-modified bone marrow dendritic cells ameliorate experimental autoimmune myasthenia gravis by up-regulated levels of IDO/Treg and partly dependent on FasL/Fas pathway.

After the publication of the original article [1], it came to the authors' attention that there was an error in the originally published version of Fig. 5b. The image of CD4+CD25+ T cells of the statin-Dex group was unintentionally replaced with the image of CD4+CD25+ T cells from the control group. The correct version of Fig. 5b is published in this Erratum.

Exosomes derived from statin-modified bone marrow dendritic cells increase thymus-derived natural regulatory T cells in experimental autoimmune myasthenia gravis.

BACKGROUND: The thymus plays an essential role in the pathogenesis of myasthenia gravis (MG). In patients with MG, natural regulatory T cells (nTreg), a subpopulation of T cells that maintain tolerance to self-antigens, are severely impaired in the thymuses. In our previous study, upregulated nTreg cells were observed in the thymuses of rats in experimental autoimmune myasthenia gravis after treatment with exosomes derived from statin-modified dendritic cells (statin-Dex). METHODS: We evaluated the effects of exosomes on surface co-stimulation markers and Aire expression of different kinds of thymic stromal cells, including cTEC, mTEC, and tDCs, in EAMG rats. The isolated exosomes were examined by western blot and DLS. Immunofluorescence was used to track the exosomes in the thymus. Flow cytometry and western blot were used to analyze the expression of co-stimulatory molecules and Aire in vivo and in vitro. RESULTS: We confirmed the effects of statin-Dex in inducing Foxp3+ nTreg cells and found that both statin-Dex and DMSO-Dex could upregulate CD40 but only statin-Dex increased Aire expression in thymic stromal cells in vivo. Furthermore, we found that the role of statin-Dex and DMSO-Dex in the induction of Foxp3+ nTreg cells was dependent on epithelial cells in vitro. CONCLUSIONS: We demonstrated that statin-Dex increased expression of Aire in the thymus, which may further promote the Foxp3 expression in the thymus. These findings may provide a new strategy for the treatment of myasthenia gravis.