Efficient and recyclable Ni-Ce-Mn-N modified ordered mesoporous carbon electrode during electrocatalytic ozonation process for the degradation of simulated high-salt phenol wastewater.

In this study, an efficient and stable NiO/CeO2/MnO2-modified nitrogen-doped ordered mesoporous carbon (NOMC) particle electrode was developed, in which the metal oxides were mosaicked within the pore channels by one-pot skeleton hybridization, and the comodification of NiO/CeO2/MnO2/N was found to improve the electrocatalytic activity and stability of the particle electrode. The improved stability of the ordered mesoporous carbon towards pore collapse was applied to the degradation of simulated high-salt phenol wastewater by an electrocatalytic ozonation process using simple binder pelletization. The modified ordered mesoporous carbon shows a specific surface area of 269.7 m2 g-1 and a pore size of 3.17 nm, and SEM and TEM were used to show that the mesoporous structure is well maintained and the metal nanoparticles are well dispersed. The electrochemically active area of the Ni2%/Ce0.5%/Mn2.5%-NOMC particle electrode reaches 224.65 mF cm-2, which indicates that NiO improves the capacitance of the ordered mesoporous carbon and accelerates the electron transfer efficiency. Encouragingly, the phenol removal efficiency is found to reach up to 93.0% for 60 min over a wide range of pH values, with an initial phenol concentration of 150 mg L-1, low current (0.03 A) and fast reaction rate (0.0895 min-1), and the presence of CeO2 ameliorates the low activity of the particle electrode under acidic conditions. These results indicate that the presence of pyridine-N and ß-MnO2 effectively mitigates carbon corrosion and improves electrode stability, as the accumulation of large amounts of ·OH at 20 min and the maintenance of a degradation efficiency of more than 90% after eight cycles provides a viable solution for the widespread practical application of ordered mesoporous carbon particle electrodes.

Immune Thrombocytopenia Plasma-Derived Exosomes Impaired Megakaryocyte and Platelet Production through an Apoptosis Pathway.

Reduced megakaryocyte (MK) apoptosis and insufficient platelet production play important roles in the pathogenesis of immune thrombocytopenia (ITP). The contribution of plasma-derived exosomes to the decreased platelet count in ITP has not been entirely understood. Here, we found the percentage of apoptotic MKs in patients with ITP was significantly lower than those in healthy volunteers. In the presence of ITP plasma-derived exosomes (ITP-Exo), the apoptosis of MKs was reduced during the process of MK differentiation in vitro, which contributed to the reduced platelet production by Bcl-xL/caspase signaling. Furthermore, in vivo study demonstrated that ITP-Exo administration led to significantly delayed platelet recovery in mice after 3.5 Gy of irradiation. All these findings indicated that ITP-Exo, as a regulator of platelet production, impaired MK apoptosis and platelet production through Bcl-xL/caspase signaling, unveiling new mechanisms for reduced platelet count in ITP.

Allogeneic haematopoietic stem cell transplantation improves outcome of adults with relapsed/refractory Philadelphia chromosome-positive acute lymphoblastic leukemia entering remission following CD19 chimeric antigen receptor T cells.

Relapsed/refractory Philadelphia chromosome-positive acute lymphoblastic leukemia (r/r Ph+ ALL) has an extremely poor prognosis. Chimeric antigen receptor T-cell (CART) therapy has acquired unprecedented efficacy in B-cell malignancies, but its role in the long-term survival of r/r Ph+ ALL patients is unclear. We analyzed the effect of CART on 56 adults with r/r Ph+ ALL who accepted split doses of humanized CD19-targeted CART after lymphodepleting chemotherapy. 51/56 (91.1%) achieved complete remission (CR) or CR with inadequate count recovery (CRi), including 38 patients with negative minimal residual disease (MRD) tested by bone marrow BCR-ABL1 copies. Subsequently, 30/51 CR/CRi patients accepted consolidative allogeneic haematopoietic stem cell transplantation (alloHSCT). Their outcomes were compared with those of 21/51 contemporaneous patients without alloHSCT. The 2-year overall survival (OS) and leukemia-free survival (LFS) of CR/CRi patients with alloHSCT were significantly superior to those without alloHSCT (58.9%, CI 49.8-68.0% vs. 22.7%, CI 12.7-32.7%, p = 0.005; 53.2%, CI 43.6-62.8% vs. 18.8%, CI 9.2-28.4%, p = 0.000, respectively). Multivariate analysis revealed that alloHSCT and MRD-negative post-CART were the independent prognostic factors for OS and LFS. CART therapy is highly effective for r/r Ph+ ALL patients, and consolidative alloHSCT could prolong their OS and LFS.

Comparative efficacy of 20 graft-versus-host disease prophylaxis therapies for patients after hematopoietic stem-cell transplantation: A multiple-treatments network meta-analysis.

BACKGROUND: Graft-versus-host disease (GVHD) is a leading cause of death in patients after hematopoietic stem-cell transplantation (HSCT). Previous studies have shown different efficacy of GVHD prophylaxis therapies. METHODS: We reviewed 46 randomized controlled trials (including 8050 participants) systematically from Jun 20, 2004 to Aug 20, 2019. These investigations compared the following drugs or their combination at therapeutic dose range for GVHD after HSCT. The main results were based on the proportion of patients who respond to these therapies. RESULTS: Cyclosporine + methotrexate + Anti-T cell globulin (ATG), tacrolimus + methotrexate + ATG, tacrolimus + bortezomib + sirolimus and cyclosporine + marrow mesenchymal stem cells (MMSCs) were significantly more efficacious than corticosteroids alone (OR: 12.15, 6.71, 6.25, 3.73). corticosteroids alone were less efficacious than all the other GVHD prophylaxis therapies tested. CONCLUSION: Cyclosporine + methotrexate + ATG may be the best choice when starting treatment for GVHD.

Mesenchymal stem cell transplantation alleviates experimental Sjögren's syndrome through IFN-ß/IL-27 signaling axis.

Rationale: Although mesenchymal stem cell (MSC) transplantation has been proved to be an effective therapeutic approach to treat experimental Sjögren's syndrome (SS), the detailed underlying mechanisms remains unknown. IL-27 has diverse influences on the regulation of T cell differentiation and was involved in SS through modulating immune response. Here we aimed to explore whether IL-27-mediated regulation of immune cells was responsible for the beneficial effects of MSC transplantation on SS. Methods: The SS-like symptoms were evaluated in IL-27 deficient and recombinant IL-27-treated NOD mice. The MSCs were infused into NOD mice via the tail vein. The histological features of submandibular glands, saliva flow rate and serum IL-27 were examined. The effects of MSCs on the IL-27 production and Th17/Treg cell in SS patients and mice in vitro and in vivo were determined for the mechanistic study. Results: This study showed that SS patients had decreased IL-27 level and increased ratio of Th17/Treg cells. Consistently, exacerbated SS-like symptoms were observed in IL-27 deficient NOD mice, along with increased ratio of Th17/Treg cells. Importantly, MSC transplantation alleviated SS-like symptoms by elevating the level of IL-27 to restore Th17/Treg balance in NOD mice. Mechanistically, MSC-secreted interferon-ß (IFN-ß) promote dendritic cells to produce IL-27. Conclusions: Thus, we have revealed a previously unrecognized function of MSC-mediated IL-27 production by DCs in suppressing SS-like syndrome, which provided evidences for clinical application of MSC in patients with SS.

Mesenchymal stem cell transplantation ameliorates Sjögren's syndrome via suppressing IL-12 production by dendritic cells.

BACKGROUND: Mesenchymal stem cells (MSCs) have been demonstrated to be effective in treating autoimmune diseases including Sjögren's syndrome (SS). We aim to compare the effects of MSC transplantation (MSCT) and the role of serum interleukin-12 (IL-12) in SS. METHODS: IL-12 levels were measured by ELISA. IL-12 mRNA transcripts in dendritic cells (DCs) were determined by RT-PCR. After co-culturing with MSCs, IL-12 mRNA transcripts in mouse and human DCs were detected. Non-obese diabetic (NOD) mice received MSCT, recombinant IL-12, or anti-IL-12 mAb treatment, respectively. Then, salivary flow rates, histopathology of salivary glands, and splenic lymphocyte subsets were examined in these mice. RESULTS: IL-12 levels in the serum were significantly increased in SS patients and positively correlated with the EULAR 2010 Sjögren's syndrome disease activity index. DCs from SS patients produced more IL-12 than those from the control. Likewise, IL-12 treatment in NOD mice significantly decreased salivary flow rates and promoted lymphocyte infiltration in salivary glands. IL-12 antibodies downregulated Th1, Th17, and Tfh cell. MSCT enhanced salivary flow rates and decreased lymphocyte infiltrations in salivary glands of NOD mice. MSCT downregulated Th17 and Tfh cells but upregulated regulatory T cells. MSCT reduced IL-12 productions in both SS patients and mice. CONCLUSION: Our results indicate that MSCs ameliorate SS possibly via suppressing IL-12 production in DCs and that IL-12 could be a potential therapeutic target of SS. TRIAL REGISTRATION: NTC00953485 . Registered June 2009.

Design and synthesis of benzofuro[3,2-b]pyridin-2(1H)-one derivatives as anti-leukemia agents by inhibiting Btk and PI3Kδ.

Btk inhibitors and PI3Kδ inhibitors play crucial roles in the treatment of leukemia, and studies confirmed that the synergetic inhibition against Btk and PI3Kδ could gain an optimal response. Herein, a series of novel benzofuro[3,2-b]pyridin-2(1H)-one derivatives were designed and synthesized as dual Btk/PI3Kδ kinases inhibitors for the treatment of leukemia. Studies indicated that most compounds could suppress the proliferation of multiple leukemia or lymphoma cells (Raji, HL60 and K562 cells) at low micromolar concentrations in vitro. Further kinase assays identified several compounds could simultaneously inhibit Btk kinase and PI3Kδ kinase. Thereinto, compound 16b exhibited the best inhibitory activity (Btk: IC50 = 139 nM; PI3Kδ: IC50 = 275 nM) and showed some selectivity against PI3Kδ compared to PI3Kß/γ. Finally, the SAR of target compounds was preliminarily discussed combined with docking results. In brief, 16b possessed of the potency for the further optimization as anti-leukemia drugs by inhibiting simultaneously Btk kinase and PI3Kδ kinase.

Mesenchymal Stem Cells Control Complement C5 Activation by Factor H in Lupus Nephritis.

Lupus nephritis (LN) is one of the most severe complications of systemic lupus erythematosus (SLE) caused by uncontrolled activation of the complement system. Mesenchymal stem cells (MSCs) exhibit clinical efficacy for severe LN in our previous studies, but the underlying mechanisms of MSCs regulating complement activation remain largely unknown. Here we show that significantly elevated C5a and C5b-9 were found in patients with LN, which were notably correlated with proteinuria and different renal pathological indexes of LN. MSCs suppressed systemic and intrarenal activation of C5, increased the plasma levels of factor H (FH), and ameliorated renal disease in lupus mice. Importantly, MSCs transplantation up-regulated the decreased FH in patients with LN. Mechanistically, interferon-α enhanced the secretion of FH by MSCs. These data demonstrate that MSCs inhibit the activation of pathogenic C5 via up-regulation of FH, which improves our understanding of the immunomodulatory mechanisms of MSCs in the treatment of lupus nephritis.

Strategies to overcome resistance mutations of Bruton's tyrosine kinase inhibitor ibrutinib.

Ibrutinib, as the first Bruton's tyrosine kinase (Btk) inhibitor, has been shown to have clinically significant activity in leukemias and lymphomas. However, the initially responsive tumors will develop resistance during the process of treatment in few patients. Here, we summarized the mechanism of acquired resistance and suggested the next-generation Btk inhibitors that override the target resistance. Moreover, the development of combination of selective antagonists or inhibitors targeting to multiple protein kinases have increased therapeutic potency to reduce the risk of the emergence of kinases inhibitor resistance. Thus, the reported combination of therapeutic drugs as an alternative therapy to overcome ibrutinib collapse or reduce the risk of the emergence of Btk inhibitor resistance also has been reviewed.

Increased expression of Bruton's tyrosine kinase in peripheral blood is associated with lupus nephritis.

Systemic lupus erythematosus (SLE) is an autoimmune disease manifested by multiorgan impairment. It is reported that B cells participate in the onset of SLE. Bruton's tyrosine kinase (Btk), as a downstream signaling molecule of B cell antigen receptor (BCR) signaling pathway, is involved in the development, activation, and survival of B cells. The aim of our study was to explore the specific role of Btk in lupus nephritis (LN). We determined the percentages of Btk+ B cells in peripheral blood mononuclear cells (PBMCs) from SLE patients by flow cytometry and analyzed the correlation between the percentage of Btk+ B cells and lupus-related clinical indexes. Immunohistochemistry was used to detect the Btk expression in kidney from LN patients and tumor surrounding tissues. Compared with controls, the frequency of Btk+ B cells in SLE patients was upregulated (p < 0.01), and it was significantly correlated with the SLE Disease Activity Index (SLEDAI) (p < 0.01), levels of plasma anti-dsDNA antibody (p < 0.05), the amount of 24-h urine protein (p < 0.05), and levels of plasma C3 (p < 0.05). The frequency of Btk+ B cells in the patients with LN was significantly higher than those without LN (p < 0.05). Although the Btk expression in glomerulus of LN patients was significantly increased compared with controls (p < 0.001), but it had no correlation with the renal pathology activity index, SLEDAI, or 24-h urine protein. In conclusion, the increased expression of Btk in peripheral blood was correlated with LN, indicating that it may be a therapeutic target for SLE.

Amphiphilic PA-induced three-dimensional graphene macrostructure with enhanced removal of heavy metal ions.

Phytic acid (PA) induced graphene macrostructures were synthesized and investigated for the sorption characteristics and mechanisms of mercury. The as-synthesized graphene foam possessed large specific surface area and amphiphilicity. FTIR and XPS analysis revealed that the as-prepared graphene macrostructure retained oxygen-containing functional groups after hydrothermal reduction and also captured new phosphorus-containing groups because of the introduction of PA. Different experimental parameters, such as pH, PA fractions and contact time were applied to probe into the Hg(II) adsorption performance of as-synthesized macrostructure. Pseudo-second-order kinetic model and Langmuir isotherm model fitted well to the obtained sorption kinetic and isothermal data. The maximum adsorption capacity at pH = 7.2 for mercury was 361.01 mg/g. The dominant mechanisms for mercury removal were mainly ion exchange and surface complexation. Real application in river water and seawater exhibited very promising results, indicating its broad prospect in water purification.

Effect of histone modifications on hMLH1 alternative splicing in gastric cancer.

hMLH1 is one of the mismatch genes closely related to the occurrence of gastric cancer. Epigenetic regulation may play more important roles than gene mutations in DNA damage repair genes to drive carcinogenesis. In this article, we discuss the role of epigenetic changes, especially histone modifications in the regulation of hMLH1 alternative splicing. Our results showed that hMLH1 delEx10, delEx11, delEx10-11, delEx16 and delEx17 transcripts were ubiquitous in sporadic Chinese gastric cancer patients and gastric cancer cell lines. Lower level of H4K16ac and H3ac was detected in hMLH1 exon 10-11 region in gastric cancer cell lines when compared with human gastric mucosal epithelial cell line GES-1. A significant decrease of hMLH1 delEx11 and delEx10-11 was observed in gastric cancer cell lines after trichostatin A treatment. H3K36me3 and H3K4me2 levels were lower in hMLH1 exon 10-11 and exon 16-17 regions in gastric cancer lines when compared with GES-1. Aberrant transcripts such as hMLH1 delEx11 and delEx10-11 were significantly higher in gastric cancer cell lines after small interfering RNA-mediated knockdown of SETD2 (the specific methyltransferase of H3K36). The hMLH1 delEx10 and delEx10-11 transcripts were increased after interference of SRSF2. Taken together, our study demonstrates that lower level of histone acetylation and specific histone methylation such as H3K36me3 correlate with aberrant transcripts in hMLH1 exon 10-11 region. SRSF2 may be involved in these specific exons skipping as well.

Comparable therapeutic potential of umbilical cord mesenchymal stem cells in collagen-induced arthritis to TNF inhibitor or anti-CD20 treatment.

OBJECTIVES: The effects of mesenchymal stem cell (MSC) transplantation on established collagen-induced arthritis (CIA) were evaluated and compared to biologic therapies. METHODS: CIA was induced with the immunisation of type II collagen (CII) in DBA/1 mice. Human umbilical cord MSC, anti-TNF antibody, rhTNFR:Fc fusion protein and anti-CD20 antibody were respectively injected intraperitoneally into CIA mice. Arthritis severity was assessed by clinical and histological scoring. The frequencies of lymphocytes in spleen were analysed, and serum concentrations of cytokines and autoantibody to CII were also measured. The ability of MSC to regulate the balance of T helper cell subsets in CII stimulated CIA CD4+ T cells was assessed in vitro. RESULTS: MSC treatment significantly decreased the severity of arthritis, which was comparable to biologic treatments. All the treatments down-regulated Th1 subset. Except anti-CD20 all the treatments decreased Th17 subset. MSC treatment enhanced the proportion of regulatory T (Treg) cells and inhibited the generation of T follicular helper (Tfh) cells. The decrease in autoantibody level was detectable in all the treated groups. In vitro MSC induced Foxp3+ T cells, and down-regulated IL-17+, IFNγ+ T cells and pathogenic IL-17+IFNγ+ or IL-17+Foxp3+ T cells. MSC also reduced the secretion of IL-1ß, IL-6, IL-17 and TNF-α among collagen-specific T cells. CONCLUSIONS: MSC show comparable effects to the known biologic treatments and correct immune imbalance in CIA. MSC might provide a promising approach for the treatment of rheumatoid arthritis.

Human Umbilical Cord Mesenchymal Stem Cells Inhibit T Follicular Helper Cell Expansion Through the Activation of iNOS in Lupus-Prone B6.MRL-Faslpr Mice.

The aberrant generation or activation of T follicular helper (Tfh) cells contributes to the pathogenesis of systemic lupus erythematosus (SLE), yet little is known about how these cells are regulated. In this study, we demonstrated that the frequency of Tfh cells was increased in lupus-prone B6.MRL-Faslpr (B6.lpr) mice and positively correlated to plasma cell proportions and serum total IgG as well as anti-dsDNA antibody levels. Transplantation of mesenchymal stem cells derived from Wharton's jelly of human umbilical cords (hUC-MSCs) ameliorated lupus symptoms in B6.lpr mice, along with decreased percentages of Tfh cells. In vitro studies showed that the differentiation and proliferation of Tfh cells were markedly suppressed by hUC-MSCs. The production of inducible nitric oxide synthase (iNOS) was dramatically upregulated in hUC-MSCs when cocultured with CD4+ T cells directly, while adding the specific inhibitor of iNOS into the coculture system significantly reversed the inhibitory effect of hUC-MSCs on Tfh cell generation. Interestingly, the efficacy of hUC-MSCs in inhibiting Tfh cells was impaired in the Transwell system, with the reduction of iNOS in both mRNA and protein levels. Taken together, our findings suggest that hUC-MSCs could effectively inhibit Tfh cell expansion through the activation of iNOS in lupus-prone B6.lpr mice, which is highly dependent on cell-to-cell contacts.

Mesenchymal stem cells upregulate Treg cells via sHLA-G in SLE patients.

BACKGROUND: Soluble human leukocyte antigen-G (sHLA-G) is a non-classical HLA class I molecule, exhibiting strong immunosuppressive properties by inducing the differentiation of T regulatory cells (Treg). Mesenchymal stem cells (MSCs) transplantation alleviates disease progression in systemic lupus erythematosus (SLE) patients. However, the underlying mechanisms are largely unknown. OBJECTIVES: To explore whether sHLA-G is involved in upregulating effects of MSCs on Treg, which contributes to therapeutic effects of MSCs transplantation in SLE. METHODS: The serum sHLA-G levels of SLE patients and healthy controls were detected by ELISA. The percentages of peripheral blood CD4+ILT2+, CD8+ILT2+, CD19+ILT2+ cells and Treg cells were examined by flow cytometry. Ten patients with active SLE, refractory to conventional therapies, were infused with umbilical cord derived MSCs (UC-MSCs) and serum sHLA-G was measured 24h and 1month after infusion. The mice were divided into three groups: C57BL/6 mice, B6.MRL-Faslpr mice infused with phosphate buffer saline (PBS), and B6.MRL-Faslpr mice infused with bone marrow MSCs (BM-MSCs). Then, the concentrations of serum Qa-2 were detected. Peripheral blood mononuclear cells (PBMCs) were isolated from SLE patients and co-cultured with UC-MSCs for 3days at different ratios (50:1, 10:1, and 2:1) with or without HLA-G antibody, and the frequencies of CD4+CD25+Foxp3+ T cells were then determined by flow cytometry. RESULTS: The concentrations of serum sHLA-G were comparable between SLE patients and healthy controls. However, there was a negative correlation between sHLA-G levels and SLE disease activity index (SLEDAI) scores in active SLE patients (SLEDAI>4). We found that serum sHLA-G levels were negatively correlated with blood urea nitrogen, serum creatinine and 24-hour urine protein in SLE patients. The sHLA-G levels were significantly lower in SLE patients with renal involvement than those without renal involvement. The expression of ILT2 on CD4+ T cells from SLE patients decreased significantly compared to that of healthy controls. A positive correlation between the frequencies of Treg and CD4+ILT2+ T cells was found in SLE patients. The levels of sHLA-G increased 24h post UC-MSCs transplantation. The concentrations of Qa-2 in BM-MSCs transplanted mice were significantly higher than those of control group. In vitro studies showed that MSCs increased the frequency of Treg cells in SLE patients in a dose-dependent manner, which was partly abrogated by the anti-HLA-G antibody. CONCLUSIONS: Our results suggested that MSCs may alleviate SLE through upregulating Treg cells, which was partly dependent on sHLA-G.

Epigenetic regulation of CDH1 exon 8 alternative splicing in gastric cancer.

BACKGROUND: The tumor suppressor gene CDH1 is critical for intercellular adhesion. In our previous work, we reported a nonfunctional CDH1 transcript that lacks the final 83 base pairs of exon 8 (1054del83). In this work, we probed the role of histone epigenetic modifications as well as DNA methylation in selection of this isoform. METHODS: RT-qPCR was used to detect CDH1 RNA expression. Methylation of CDH1 was analyzed by bisulphite sequencing PCR. ChIP assay was performed to show histones level. Cell lines were treated with DNA methyltransferase inhibitor AZA, HDAC inhibitor TSA, or siRNA oligonucleotides to test regulation of CDH1 splicing. RESULTS: Greater CDH1 1054del83 transcripts were observed in gastric cancer (GC) cell lines than human gastric mucosal epithelial cell line GES-1. All the cell lines showed significant methylation pattern at the CpG sites of CDH1 exon 8. AZA treatment did not influence selection of 1054del83 transcripts. A significant decrease in acetylation for histones H3 and H4K16Ac in an internal region of the CDH1 gene surrounding the alternative exon 8 were detected in GC cell lines. Treatment with TSA preferentially expressed the correctly spliced transcript and not the exon 8 skipped aberrant transcripts, showing that histone acetylation was involved in the splicing regulation. SiRNA-mediated knockdown of SETD2 (The specific methyltransferase of H3K36) decreased exclusion of exon 8, suggesting that the presence of this mark correlates with increased skipping of the final 83 base pairs of CDH1 exon 8. However, CDH1 splicing was not affected by SRSF2 knockdown. CONCLUSIONS: H3K36me3 correlates with increased skipping of the final 83 base pairs of CDH1 exon 8. Histone acetylation was involved in the splicing regulation as well.

Leptin and Neutrophil-Activating Peptide 2 Promote Mesenchymal Stem Cell Senescence Through Activation of the Phosphatidylinositol 3-Kinase/Akt Pathway in Patients With Systemic Lupus Erythematosus.

OBJECTIVE: Mesenchymal stem cells (MSCs) derived from patients with systemic lupus erythematosus (SLE) exhibit enhanced senescence. Cellular senescence has been reported to be induced by several inflammatory cytokines, including interferon-α (IFNα) and IFNγ, that are involved in the pathogenesis of SLE. We undertook this study to investigate whether the inflammatory environment in SLE could affect MSC senescence. METHODS: Cellular senescence was measured by staining of senescence-associated ß-galactosidase and by expression of the cell cycle inhibitors p53 and p21. Eighty cytokines and chemokines in serum from healthy controls and patients with SLE were identified by cytokine antibody array. RESULTS: SLE serum promoted senescence of MSCs, which was reversed by the phosphatidylinositol 3-kinase (PI3K)/Akt signaling inhibitor LY294002 but not by the JAK/STAT inhibitor AG490 and not by the MEK/ERK inhibitor PD98059. Cytokine antibody array analysis revealed that leptin and neutrophil-activating peptide 2 (NAP-2) were the 2 factors most significantly elevated in SLE serum compared with normal serum. Blockade of leptin or NAP-2 in MSC cultures abolished SLE serum-induced senescence, while direct addition of these 2 factors could promote senescence in cultures of normal MSCs. Inhibition of PI3K/Akt signaling with LY294002 reduced leptin- and NAP-2-induced senescence in MSCs. CONCLUSION: Taken together, our data show that leptin and NAP-2 act synergistically to promote MSC senescence through enhancement of the PI3K/Akt signaling pathway in SLE patients.