Shanshan Liu

Endothelial cell (EC) senescence driven by oxidative stress is a pivotal contributor to vasculopathy in systemic sclerosis (SSc), leading to impaired angio

Umbilical cord‐derived mesenchymal stromal cells (MSCs) transplantation is a promising therapy for systemic sclerosis (SSc) because of their distinctive antifibrotic and immunomodulatory properties. To enhance the effects of MSCs transplantation, novel engineered MSC aggregates preconditioned with human E/N‐cadherin fusion protein (hE/N‐cad‐Fc) and interleukin‐6 (IL‐6) for SSc treatment are fabricated and named 3D‐Cad/IL6‐MSCs. These novel‐engineered MSC aggregates possess tighter cellular cohesion and exhibit enhanced antiapoptotic, immunosuppressive, and proangiogenic capabilities according to transcriptomic analyses. Moreover, 3D‐Cad/IL6‐MSCs have improved immunoregulatory effects on peripheral blood mononuclear cells (PBMCs), CD4⁺ T cells, and CD8⁺ T cells in vitro because of the synergistic preconditioning from IL‐6 and bioactive hE/N‐cad‐Fc. Upon intravenous injection, 3D‐Cad/IL6‐MSCs significantly mitigate skin and lung fibrosis and prolong the retention duration in bleomycin (BLM)‐induced SSc mouse model. In detail, they suppress excessive infiltration of macrophages and T cells in the injured skin and lungs and reestablish the immune equilibrium of circulating CD4⁺ T‐cell subsets in vivo. These results suggest that 3D‐Cad/IL6‐MSCs are ideal candidates for SSc therapy and optimize the clinical utilization of MSCs.

This study was designed to explore the metabolism features in systemic lupus erythematosus (SLE) and to investigate the role and regulatory mechanism of taurine in the control of CD4+ T cells and the progression of SLE. Metabolomic profiles of sera from SLE patients and healthy controls (HCs) were analyzed by mass spectrometry. The therapeutic effects of taurine in vivo were observed in resiquimod (R848) induced mice, and the effects of taurine on various functions of CD4+ T cells were examined by flow cytometry. The effect of mTORC1 agonist MHY1485 on the regulatory capacity of taurine was examined in vitro. Both untargeted metabolomics assays and independent sample validation showed that serum levels of taurine were reduced in SLE patients compared to HCs (P<0.0001), which was inversely correlated with disease activity scores (P<0.05). Taurine supplementation relieved the progression of lupus in R848 induced mice, characterized by a decrease in anti-dsDNA (P<0.01) and proteinuria (P<0.05) and a reduction in the severity of nephritis (P<0.05). And, taurine supplementation improved the differentiation of cell subsets such as Th17 (P<0.001) and Treg cells (P<0.001) in these mice. In vitro, taurine suppressed reactive oxygen species production (P<0.001), proliferation (P<0.0001) and senescence (P<0.0001) of mouse spleen cells. The level of pS6 (P<0.0001) but not AKT in CD4+ T was significantly decreased after taurine treatment, while mTORC1 agonists partially blocked the effect of taurine on CD4+ T cells. Taurine may play a therapeutic role by ameliorating CD4+ T cell abnormalities through inhibition of mTORC1 signaling in SLE.

Umbilical cord-derived mesenchymal stromal/stem cells (UC-MSCs) present low immunogenicity and potent immunomodulatory effects for treating various diseases. Human UC-MSCs are a heterogeneous population consisting of three main subpopulations with different cell shapes, proliferation rates, differentiation abilities, and immune regulatory functions. Previously, BAMBIhighMFGE8high UC-MSCs, the first subgroup successfully isolated from UC-MSCs were found to fail to alleviate lupus nephritis. Hence, the function and underlying mechanism of this subgroup in MSC therapy for diseases remains unknown. It is necessary to isolate and further investigate BAMBIhighMFGE8high UC-MSCs in terms of their phenotype, metabolism, and function to completely understand the nature of this MSC subgroup. In this protocol, we describe a detailed method for isolating the BAMBIhighMFGE8high subpopulation from human UC-MSCs. The subpopulation of UC-MSCs is labeled with two surface markers, BAMBI and MFGE8, by flow cytometry sorting. The isolated cells are cultured and verified by flow cytometry analysis. The specific genes expressed in the BAMBIhighMFGE8high UC-MSCs are identified by RT-qPCR. This protocol results in highly efficient and pure cell sorting and describes the marker profiles of the BAMBIhighMFGE8high UC-MSCs.

Umbilical cord-derived mesenchymal stromal/stem cells (UC-MSCs) present low immunogenicity and potent immunomodulatory effects for treating various diseases. Human UC-MSCs are a heterogeneous population consisting of three main subpopulations with different cell shapes, proliferation rates, differentiation abilities, and immune regulatory functions. Previously, BAMBIhighMFGE8high UC-MSCs, the first subgroup successfully isolated from UC-MSCs were found to fail to alleviate lupus nephritis. Hence, the function and underlying mechanism of this subgroup in MSC therapy for diseases remains unknown. It is necessary to isolate and further investigate BAMBIhighMFGE8high UC-MSCs in terms of their phenotype, metabolism, and function to completely understand the nature of this MSC subgroup. In this protocol, we describe a detailed method for isolating the BAMBIhighMFGE8high subpopulation from human UC-MSCs. The subpopulation of UC-MSCs is labeled with two surface markers, BAMBI and MFGE8, by flow cytometry sorting. The isolated cells are cultured and verified by flow cytometry analysis. The specific genes expressed in the BAMBIhighMFGE8high UC-MSCs are identified by RT-qPCR. This protocol results in highly efficient and pure cell sorting and describes the marker profiles of the BAMBIhighMFGE8high UC-MSCs.

Objective To investigate the role of curcumin in the treatment of lupus nephritis (LN) by inhibiting the migration of neutrophils and the underlying mechanism involved. Methods Two lupus mouse models, MRL/lpr mice and R848-treated mice, were treated with 50 mg/kg curcumin by intraperitoneal injection. H&E and Masson staining were used to estimate histopathological changes in the kidney. Immunofluorescence was used to assess the deposition of immune complexes. The expression of inflammatory factors was detected by enzyme-linked immunosorbent assay (ELISA) and real-time reverse transcription polymerase reaction (RT-PCR), and the protein expression was detected by western blotting. Results We revealed the remarkable potential of curcumin in improving inflammatory conditions in both MRL/lpr mice and R848-induced lupus mice. Curcumin effectively decelerates the progression of inflammation and diminishes the infiltration of neutrophils and their release of pivotal inflammatory factors, thereby reducing inflammation in renal tissues. Mechanistically, curcumin significantly inhibits the expression of p-PI3K, p-AKT and p-NF-κB, which are upregulated by interleukin-8 to induce neutrophil migration and renal inflammation, thereby reducing neutrophil migration and the release of inflammatory factors. Conclusion Curcumin significantly inhibits the recruitment of neutrophils and the release of proinflammatory factors in the kidney by inhibiting the PI3K/AKT/NF-κB signalling pathway, providing new therapeutic targets and medication strategies for the treatment of LN.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by the production of autoantibodies and tissue inflammation. Mesenchymal stem cells (MSCs) have emerged as a promising candidate therapy for SLE owing to the immunomodulatory and regenerative properties. Circulating miRNAs are small, single-stranded noncoding RNAs in a variety of body fluids that regulate numerous immunologic and inflammatory pathways. Recent studies have revealed many differentially expressed circulating miRNAs in autoimmune diseases including SLE. However, the role of circulating miRNAs in SLE has not been extensively studied. Here, we performed small RNA sequencing analysis to compare the circulating miRNA profiles of SLE patients before and after MSC transplantation (MSCT), and identified a significant decrease of circulating miR-320b level during MSCT. Importantly, we found that the expression of circulating miR-320b and its target gene MAP3K1 was closely associated with SLE disease activity. The in vitro experiments showed that decreased MAP3K1 level in SLE peripheral blood mononuclear cells (PBMCs) was involved in CD4 T-cell proliferation. In MRL/lpr mice, miR-320b overexpression aggravated symptoms of SLE, while miR-320b inhibition could promote disease remission. Besides, MSCs regulate miR-320b/MAP3K1 expression both in vitro and in vivo. Our results suggested that circulating miR-320b and MAP3K1 may be involved in CD4 T-cell proliferation in SLE. This trial is registered with NCT01741857.

Mixed human umbilical cord‐derived mesenchymal stem cells (UC‐MSCs) are widely applied in clinical trials to treat various diseases due to their multipotent differentiation potential and immune regulatory activities. However, the lack of a clear understanding of their heterogeneity hampers their application to precisely treat diseases. Moreover, few studies have experimentally authenticated the functions of so‐called UC‐MSC subpopulations classified from scRNA‐seq samples. Here, this work draws a large‐scale single‐cell transcriptomic atlas and identified three clusters (C1, C2, and C3), representing the primed, intermediate, and stem statuses individually. The C1 and C3 clusters feature higher expression of cytokines and stemness markers, respectively. Surprisingly, further experimental assays reveal that the BAMBI^highMFGE8^high C1 subgroup has a unique phenotype, distinct transcriptomic profile, and limited adipogenic differentiation potential but compromised immunosuppressive activity in vitro and in vivo in lupus mice. Thus, this work is helpful to clarify the nature of human UC‐MSCs and to choose optimal MSC types to treat specific diseases in the future.