Combining single-cell RNA sequencing and population-based studies reveals hand osteoarthritis-associated chondrocyte subpopulations and pathways

Hand osteoarthritis is a common heterogeneous joint disorder with unclear molecular mechanisms and no disease-modifying drugs.In this study,we performed single-cell RNA sequencing analysis to compare the cellular composition and subpopulationspecific gene expression between cartilage with macroscopically confirmed osteoarthritis(n=5)and cartilage without osteoarthritis(n=5)from the interphalangeal joints of five donors.Of 105142 cells,we identified 13 subpopulations,including a novel subpopulation with inflammation-modulating potential annotated as inflammatory chondrocytes.Fibrocartilage chondrocytes exhibited extensive alteration of gene expression patterns in osteoarthritic cartilage compared with nonosteoarthritic cartilage.Both inflammatory chondrocytes and fibrocartilage chondrocytes showed a trend toward increased numbers in osteoarthritic cartilage.In these two subpopulations from osteoarthritic cartilage,the ferroptosis pathway was enriched,and expression of iron overload-related genes,e.g.,FTH1,was elevated.To verify these findings,we conducted a Mendelian randomization study using UK Biobank and a population-based cross-sectional study using data collected from Xiangya Osteoarthritis Study.Genetic predisposition toward higher expression of FTH1 mRNA significantly increased the risk of hand osteoarthritis(odds ratio=1.07,95%confidence interval:1.02–1.11)among participants(n=332668)in UK Biobank.High levels of serum ferritin(encoded by FTH1),a biomarker of body iron overload,were significantly associated with a high prevalence of hand osteoarthritis among participants(n=1241)of Xiangya Osteoarthritis Study(P-for-trend=0.037).In conclusion,our findings indicate that inflammatory and fibrocartilage chondrocytes are key subpopulations and that ferroptosis may be a key pathway in hand osteoarthritis,providing new insights into the pathophysiology and potential therapeutic targets of hand osteoarthritis.

Peripheral T-lymphocyte subpopulations in different clinical stages of chronic HBV infection correlate with HBV load

AIM： To characterize the peripheral T-cell subpopulation profiles and their correlation with hepatitis B virus （HBV） replication in different dinical stages of chronic HBV infection. METHODS： A total of 422 patients with chronic HBV infection were enrolled in this study. The patients were divided into three stages： immune-tolerant stage, immune active stage, and immune-inactive carrier stage. Composition of peripheral T-cell subpopulations was determined by flow cytometry. HBV markers were detected by enzyme-linked immunosorbent assay. Serum HBV DNA load was assessed by quantitative real-time poiymerase chain reaction.RESULTS： CD8^＋ T-cells were significantly higher in patients at the immune-tolerant stage than in patients at the immune-active and -inactive carrier stages （36.87 ± 7.58 vs 34.37 ± 9.07, 36.87 ± 7.58 vs 28.09 ± 5.64, P 〈 0.001）. The peripheral blood in patients at the immune-tolerant and immune active stages contained more CD8^＋ T-cells than CD4^＋ T-cells （36.87 ± 7.58 vs 30.23 ± 6.35, 34.37 ± 9.07 vs 30.92 ± 7.40, P 〈 0.01）, whereas the peripheral blood in patients at the immune- inactive carrier stage and in normal controls contained less CD8^＋ T-cells than CD4^＋ T-cells （28.09 ± 5.64 vs 36.85 ±6.06, 24.02 ± 4.35 vs 38.94 ± 3.39, P 〈 0.01）. ANOVA linear trend test showed that CD8^＋ T-cells were significantly increased in patients with a high viral load （39.41 ± 7.36, 33.83 ± 7.50, 31.81 ± 5.95 and 26.89 ± 5.71, P 〈 0.001）, while CD4^＋ T-cells were significantly increased in patients with a low HBV DNA load （37.45 ± 6.24, 33.33 ± 5.61, 31.58 ± 6.99 and 27.56 ± 5.49, P 〈 0.001）. Nultiple regression analysis displayed that log copies of HBV DNA still maintained its highly significant coefficients for T-cell subpopulations, and was the strongest predictors for variations in CD3^＋, CD4^＋ and CD8^＋ cells and CD4^＋/CD8^＋ ratio after adjustment for age at HBV-infection, maternal HBV-infection status, presence of hepatitis B e antigen and HBV mutation.CONCLUSION： Differences in peripheral T-cell subpopulation profiles can be found in different clinical stages of chronic HBV infection. T-cell impairment is significantly associated with HBV load.

Hepatitis B virus DNA is more powerful than HBeAg in predicting peripheral T-lymphocyte subpopulations in chronic HBV-infected individuals with normal liver function tests

AIM:To investigate the peripheral T-lymphocyte subpopulation profile,and its correlations with hepatitis B virus(HBV) replication level in chronic HBV-infected(CHI) individuals with normal liver function tests(LFTs) . METHODS:Frequencies of T-lymphocyte subpopu-lations in peripheral blood were measured by flow cytometry in 216 CHI individuals. HBV markers were detected with ELISA. Serum HBV DNA load was assessed with quantitative real-time PCR. Information of age at HBV infection,and maternal HBV infection status was collected. ANOVA linear trend test and linear regression were used in statistical analysis. RESULTS:CHI individuals had significantly decreased relative frequencies of CD3+,CD4+ subpopulationsand CD4+/CD8+ ratio,and increased CD8+ subset percentage compared with uninfected individuals(all P < 0.001) . There was a significant linear relationship between the load of HBV DNA and the parameters of T-lymphocyte subpopulations(ANOVA linear trend test P < 0.01) . The parameters were also significantly worse among individuals whose mothers were known to be HBV carriers,and those having gained infection before the age of 8 years. In multiple regressions,after adjustment for age at HBV infection and status of maternal HBV infection,log copies of HBV DNA maintained its highly significant predictive coefficient on T-lymphocyte subpopulations,whereas the effect of HBeAg was not significant. CONCLUSION:HBV DNA correlates with modification in the relative T-lymphocyte subpopulation frequencies. High viral load is more powerful than HBeAg in predicting the impaired balance of T-cell subsets.

Hypertonic saline resuscitation maintains a more balanced profile of T-lymphocyte subpopulations in a rat model of hemorrhagic shock

Objective: To investigate the potential and early effect of hypertonic saline resuscitation on T-lymphocyte sub- populations in rats with hemorrhagic shock. Methods: A model of rat with severe hemorrhagic shock was established in 18 Sprague-Dawley (SD) rats. The rats were randomly divided into Sham group, HTS group (hypertonic saline resuscitation group) and NS group (normal saline resuscitation group). Each group contained 6 rats. The CD4+ and CD8+ subpopulations of T-lymphocytes in peripheral blood were detected respectively before shock and after resuscitation by double antibody labelling and flow cytometry. Results: In the early stage after hemorrhagic shock, fluid resuscitation and emergency treatment, the CD4+ lymphocytes of peripheral blood in HTS and NS groups markedly increased. Small volume resuscitation with HTS also induced peripheral CD8+ lymphocytes to a certain extent, whereas NS resuscitation showed no effect in this respect. Consequently, compared with Sham and HTS groups, CD4+/CD8+ ratio of peripheral blood in NS group was obviously increased, and showed statistically differences. Conclusion: In this model of rat with severe hemorrhagic shock, small volume resuscitation with HTS is more effective than NS in reducing immunologic disorders and promoting a more balanced profile of T-lymphocyte subpopula- tions regulating network.

Flow cytometric characterizations of leukocyte subpopulations in the peripheral blood of northern pig-tailed macaques （Macaca leonina）

Pig-tailed macaques(Macaca nemistrina group) have been extensively used as non-human primate animal models for various human diseases in recent years, notably for AIDS research due to their sensitivity to HIV-1. Northern pig-tailed macaques(M. leonina) are distributed in China and other surrounding Southeast Asia countries. Although northern pig-tailed macaques have been bred on a large scale as experimental animals since 2012, the reference value of normal levels of leukocytes is not available. To obtain such information, 62 blood samples from male and female healthy northern pig-tailed macaques at different ages were collected. The normal range of major leukocyte subpopulations, such as T lymphocytes, B lymphocytes, natural killer(NK) cells, monocytes, and the expression levels of activation or differentiation related molecules(CD38, HLA-DR, CCR5, CD21, IgD, CD80 and CD86) on lymphocytes were analyzed by flow cytometry. The counts of B cells decreased with age, but those of CD8+ T cells and NK cells and the frequency of CD38+HLA-DR+CD4+ T cells were positively correlated with age. The counts of leukocyte subpopulations were higher in males than those in females except for CD4+ T cells. Males also showed higher expression levels of Ig D and CD21 within B cells. This study provides basic data about the leukocyte subpopulations of northern pig-tailed macaques and compares this species with commonly used Chinese rhesus macaques(M. mulatta), which is meaningful for the biomedical application of northern pig-tailed macaques.

Early Changes of Peripheral Blood Lymphocyte Subpopulations in Patients with Occupational 2,4-dinitrophenol Poisoning

2,4-dinitrophenol （DNP）, an organic compound which frequently used in industry, is considered to have high toxicity. This study aimed to investigate the early changes of lymphocyte subpopulations in patients with occupational 2,4-DNP poisoning. Totally 9 patients with acute occupational 2,4-DNP poisoning and 30 healthy volunteers as control were enrolled. The patients received immediately comprehensive supportive treatments, including large-dose glucocorticoid and repeated hemoperfusion （HP）. The ratio of CD4＋/CD8＋ T cells were significantly higher in patients upon admission compared to healthy controls （P 〈 0.01）; however, counts of total lymphocytes, CD3＋, CD3＋CD4＋, CD3＋CD8＋, B （CD19＋）, and natural killer （NK） cells （CD16＋CD56＋） were significantly reduced （all P 〈 0.001）. The NK cell count was negatively correlated with initial plasma 2,4-DNP concentration （r = -0.750, P = 0.026）. Thus, acute occupational 2,4-DNP poisoning was accompanied by immediate complex immune cell reactions, especially NK cells might play important role in severe 2,4-DNP poisoning.

Olfactory ensheathing cells for spinal cord repair: crucial differences between subpopulations of the glia

OECs for spinal cord repair： Is repairing the iniured spinal cord by olfactory ensheathing cell （OEC） transplantation pos- sible？ A recent human trial in which a paralysed man regained some function after transplantation of partially purified OECs suggests that this therapy may be a successful approach （Ta- bakow et al., 2014）. In another human trial in which olfactory mucosa lamina propria was transplanted, patients recovered some motor and sensory function （Wang et al., 2015）. While these results show promise, it is clear that improvements are needed to provide patients with increased functional output. Strategies to improve the therapeutic use of OECs may include improving the purification of the OECs used for transplantation, using them in combination with growth factors to combat the inhibitory environment and improve anon growth, the use of nerve bridges, advanced physiotherapy and the use of exo- skeleton robotics to reinforce functional connections. Of all these approaches, it is probably is primarily addressed to ensure crucial that the purity of OECs consistency in outcomes.

Aldehyde dehydrogenase activity helps identify a subpopulation of murine adipose-derived stem cells with enhanced adipogenic and osteogenic differentiation potential

AIMTo identify and characterize functionally distinct subpopulation of adipose-derived stem cells (ADSCs). METHODSADSCs cultured from mouse subcutaneous adipose tissue were sorted fluorescence-activated cell sorter based on aldehyde dehydrogenase (ALDH) activity, a widely used stem cell marker. Differentiation potentials were analyzed by utilizing immunocytofluorescece and its quantitative analysis. RESULTSApproximately 15% of bulk ADSCs showed high ALDH activity in flow cytometric analysis. Although significant difference was not seen in proliferation capacity, the adipogenic and osteogenic differentiation capacity was higher in ALDHHi subpopulations than in ALDHLo. Gene set enrichment analysis revealed that ribosome-related gene sets were enriched in the ALDHHi subpopulation. CONCLUSIONHigh ALDH activity is a useful marker for identifying functionally different subpopulations in murine ADSCs. Additionally, we suggested the importance of ribosome for differentiation of ADSCs by gene set enrichment analysis.

Analysis of Genetic Diversity of Four Subpopulations of Chimonobambusa rivularis Yi in Sichuan

A study of the genetic diversity within four subpopulations of Chimonobambusa rivularis Yi and adaptations to altitude, habitat and related factors in Qionglai City of Sichuan province in China, analyzed by random amplified polymorphic DNA technique. 22 random primers were selected in the amplification and 375 repetitive loci with 350 polymorphic loci were produced. The total average percentage of amplification loci was 93.3%. The genetic diversity of every subpopulation was medium on （the percentage of amplification loci was 49.33%-66.67%）. The genetic diversity of high altitude samples of Zhengtiantai was lower than that of low altitude Wutonggang＇s. There was no obvious differentiation between two subpopulations of Zhengtiantais. The correlation is very low between altitude and the amplification loci and the genetic distance, Pearson correlation coefficient was 0.431 and 0.488 （P 〈 0.01）. Through investigation, the primary cause of heredity multiplicity drops was that the habitat had been destroyed by tourism development and other human disturbance.

MINIMUM ATTRIBUTE CO-REDUCTION ALGORITHM BASED ON MULTILEVEL EVOLUTIONARY TREE WITH SELF-ADAPTIVE SUBPOPULATIONS

Attribute reduction is an important process in rough set theory.Finding minimum attribute reduction has been proven to help the user-oriented make better knowledge discovery in some cases.In this paper,an efficient minimum attribute reduction algorithm is proposed based on the multilevel evolutionary tree with self-adaptive subpopulations.A model of multilevel evolutionary tree with self-adaptive subpopulations is constructed,and interacting attribute sets are better decomposed into subsets by the self-adaptive mechanism of elitist populations.Moreover it can self-adapt the subpopulation sizes according to the historical performance record so that interacting attribute decision variables are captured into the same grouped subpopulation,which will be extended to better performance in both quality of solution and competitive computation complexity for minimum attribute reduction.The conducted experiments show the proposed algorithm is better on both efficiency and accuracy of minimum attribute reduction than some representative algorithms.Finally the proposed algorithm is applied to magnetic resonance image(MRI)segmentation,and its stronger applicability is further demonstrated by the effective and robust segmentation results.

Identification of Sperm Subpopulations in Water Buffalo Ejaculates： Changes in Cryopreservation Stages and Bull Variation

This study aimed to identify and characterize the sperm subpopulations existing in water buffalo semen using a computer assisted sperm analyzer （CASA）, as well as assess the effects of cryopreservation on the sperm subpopulation structure and evaluate bull variability. The semen of eight Bulgarian Murrah bulls was collected by four times in an interval of one week each. The semen was cryopreserved following a standard protocol and sperm kinematics was assessed. Clustering methods were applied to individual sperms, forming two significantly different （P 〈 0.05） subpopulations （P1 and P2）. Subpopulation P1 represents those spermatozoa that moved most rapidly and progressively （46.29%）, and subpopulation P2 includes spermatozoa with relatively low velocity or poorly motile but with high progressiveness （53.41%）. There was a decline on the population of P1 sperms from fresh （52.52%）, pre-freeze （45.73%） to post-thaw （35.17%） stages and significant difference on the sperm kinematics between P1 and P2. A significant decline in the values of distance, velocity and amplitude of lateral head （ALH） parameters were observed at post-thaw stage, while an increase was observed on trajectory and beat cross frequency （BCF） kinematics. Values of sperm kinematics were also significantly different （P 〈 0.05） among all bulls. The frequency distribution of spermatozoa on both subpopulations P1 and P2 was quite similar for all bulls in pre-freeze and post-thaw stages, but with significant （P 〈 0.05） variability on fresh stage. Bulls with the highest maintained frequency of P1 sperms are denoted as good freezer bulls. In sum, kinematic characterization of water buffalo sperm and clustering into subpopulation enable to identify bulls that are more resistant to cryopreservation and production of quality semen for genetic propagation.

Analysis of Peripheral T-Lymphocyte Subpopulations in Patients with Early Syphilis by Flow Cytometry

Objective: To study the cellular immunity function of patientswith early syphilis and the effects on immune modifiersEsberitox N or IFN. Methods: T-lymphocyte subpopulations of the peripheralblood in 44 patients with syphilis and 40 healthy controls wereexamined by flow cytometry. Results: The number of CD_4+ cells and the CD_4+/CD_8+ ratioin patients with syphilis were found to be significantly lowerthan those in the control (P<0.0l), while the number of CD_8+cells was higher than that in the control (P<0.01). TheCD_4+/CD_8+ ratio in those with active disease was lower thanthat in those who had been cured (P<0.05). The CD_4+ countand the CD_4+/CD_8+ ratio in those treated with antibiotics alone(Penicillin G or Cephalosporins) were lower than those treatedwith both antibiotics and immunomodulators (P<0.05). Conclusions: Cellular immunity in the patients with earlysyphilis was prominently suppressed, and treatment withimmunomodulators may be helpful for the recovery of cellularimmunity of these patients.

Correlation of Quantitative Changes in Bone Marrow Lymphocyte Subpopulations with Some Rhabdomyosarcoma Prognosis Factors in Children

Rationale: The known prognosis factors for rhabdomyosarcoma (RMS) in children do not always explain the unsatisfactory outcome of treatment. Changes in the subpopulation composition of Bone Marrow (BM) effector cells during the development of RMS may indicate new directions for the search for prognostic factors and points for the impact of targeted therapy. Purpose: To identify correlations between quantitative changes in the levels of subpopulations of T, B and NK-lymphocytes of BM and known risk factors for RMS in children. Objects: The study included 31 patients. The main group included 16 patients with RMS, average age—6.8 ± 1.0 years, while children 1 - 10 years old—13 (81.3%), over 10 years old—3 (18.8%) people, girls and boys were 8 people each. The embryonic variant of RMS was established in 10 (62.5%) cases, the alveolar variant—in 4 (25%) cases, in two patients (12.5%), the histological variant was not established. In 12 (75%) patients, an unfavorable localization of the RMS (parameningeal, extremities, prostate, bladder) was revealed, in 4 patients (25%), the localization of the tumor was regarded as favorable. Patients with T2b—13 (81.2%) and T2a—2 (12.5%) stages prevailed. Regional and distant metastases were detected in 10 (52.6%) patients. The comparison group included 15 children in whom the presence of malignant neoplasia was excluded, the average age was 8.4 ± 1.5 years, 11 boys (73.7%) and 4 girls (26.3%). Methods: All patients underwent morphological (myelogram counting) and immunological (quantitative analysis of lymphocytic subpopulations) bone marrow studies. Immunophenotyping in all patients was carried out by direct immunofluorescence using a triple fluorescent label. Results: Significant differences in the levels of subpopulations of BM T-lymphocytes were found when comparing the values of the main group, distributed by localization and histological variant, with the data obtained in the control group of patients. For example, the percentage of CD3+ T cells with the co-stimulatory molecule CD28+ was significantly higher in patients with parameningeal RMS (p = 0.010). Conclusion: Each clinical group of patients has its own individual immunological characteristics. The results obtained by us can be considered indicative and regarded as starting points for further study of the peculiarities of the subpopulation composition of BM in patients with RMS.

T Lymphocyte Subpopulations in Normal Pregnancies and Those Complicated by Eclampsia in Kaduna State, Nigeria

Background: Eclampsia, the occurrence of generalized convulsion(s) in association with signs of preeclampsia [PE] (hypertension and proteinuria) in pregnancy has remained a significant public threat in Nigeria, contributing to maternal and perinatal morbidity and mortality. This study was a comparative cross-sectional study conducted in some selected hospitals in Kaduna State, between April 2014 and November 2015. Subjects and Methods: Blood (3 mls) was collected into an ethylenediaminetetraaccetic acid (EDTA) vacutainer tube from third trimester women diagnosed with eclampsia (EC;n = 38) and healthy pregnant controls (PC;n = 38)—age and parity matched and healthy non-pregnant controls (NPC;n = 38)—age matched. T Cell subpopulations and Complete Blood Count levels were measured by Sysmex, Auto blood analyzer and flow cytometry respectively. Participants with smear positive malaria, seropositive for human immunodeficiency virus (HIV), any other clinical infection or refused consent were excluded from this study. Data obtained were analyzed using analysis of variance (ANOVA) and Post Hoc test. A p-value of less than 0.05 was considered to be significant. Result: Overall, results showed a depressed (mean ± Standard deviation (SD): CD3+ T cell (65.6 ± 15.5%;1225.5 ± 401.5 cell/μL), CD4+ T cell (36.1 ± 8.7%;657.1 ± 189.9 cell/μL), and a low CD4/CD8 value in women with EC (1.4 ± 0.5) and PC (1.5 ± 0.3) compared to NPC (1.9 ± 0.6) control (p < 05), while the total white blood cell count, and differential percentage neutrophils count were noted to be elevated among the eclamptic women (9.8 ± 4.9 × 109/L;70.3 ± 12.0%) compared to PC (6.9 ± 3.6 × 109/L;64.6 ± 8.1%) and NPC (5.6 ± 2.0 × 109/L;48.5 ± 10.7%), p < 0.05. Conclusion: Eclampsia was associated with significantly depressed CD3+ and CD4+ T lymphocyte, and increased percentage differential neutrophil counts.

Phenotype-Directed DNA Nanomachine for in Situ Analysis of Stem Cell-like Subpopulation in Breast Cancer

The cancer stem cell hypothesis provides a basis for prediction of the recurrence and risk of metastasis in breast cancer.However,the unique expression pattern of stemness markers and the presence of nonstem-like cancer cells with varied phenotypes have brought great challenges to the characterization of breast cancer stem cells.To address these challenges,a phenotype-directed DNA nanomachine has been designed for high-accuracy labeling and in situ analysis of the stem cell-like subpopulation in breast cancer.The key for the design is to use cell surfaceanchored inputs to activate the nanomachine,which undergoes different branch migration pathways such that the signal strand can only be brought onto the cancer cells having the stem cell-like phenotype.Highly sensitive determination and single-step isolation of the stem cell-like subpopulation were achieved by incorporating functional groups into the signal strand such that the nanomachine was successfully applied in a tumor-bearing mouse model.Overall,the approach provides for a substantial improvement in capability for the analysis of the breast cancer stem cell-like subpopulation,and it is expected that the new approach will advance the use of DNA nanomachines in cancer-related studies.

Defining two subpopulations of marginal zone B cells

Marginal zone(MZ)B cells,which are composed of heterogeneous subpopulations,are participate in the rapid response to antigens.Lee et al.showed that MZ B cells can be divided into two distinct subpopulations based on CD80 expression.These two subpopulations of MZ B cells exhibit differential autoreactivity,radiosensitivity,and functional capacities.

Single-Nucleus RNA Sequencing Reveals Cardiac Macrophage Landscape in Hypoplastic Left Heart Syndrome

Background:Hypoplastic left heart syndrome(HLHS)is one of the most challenging congenital heart diseases in clinical treatment.In cardiac tissues,resident macrophages fulfill critical functions in maintaining a stable cardiac state and have strong regenerative capacity and organ specificity.However,the molecular mechanisms of macro-phages in HLHS remained unclear.Methods:Single-nucleus RNA sequencing(snRNA-seq)data of HLHS and healthy control(donors)samples obtained from the Gene Expression Omnibus(GEO)database were normalized and clustered using the Seurat package.The“FindMarkers”function was used to screen differentially expressed genes(DEGs)between the HLHS and donor groups and to analyze the functional enrichment of the set of genes of interest.Finally,cell-cell communication,pseudotime,and single-cell regulatory network inference and cluster-ing(SCENIC)analyses were used to study the mechanisms of macrophages in HLHS.Results:Based on the snRNA-seq data of HLHS and donors,we identified a total of 9 cell clusters,among which the proportion of macrophages was significantly less in the HLHS group than in the control group.Subdivision of macrophage subpopulations(Macrophages 1,2,and 3)showed that Macrophages 1 was mainly involved in nervous system development,angiogenesis,and apoptotic processes.In addition,analysis of communication between Macro-phages 1 and cardiomyocytes revealed that ligand-acceptor pairs such as GAS6/AXL,IL6,IGF1,THY1,and L1CAM were present only in the donor group.Finally,pesudotime and SCENIC analyses demonstrated that FOXO3 and ELF2 played a critical role for Macrophages 1 to maintain cardiac function in patients with HLHS.Conclusion:Our study improved the current understanding of the molecular mechanisms of macrophage devel-opment in HLHS,showing that manipulating the regulatory role of macrophages in the heart can be a novel treat-ment for HLHS.

Single-cell sequencing technology in diabetic wound healing:New insights into the progenitors-based repair strategies

Diabetes mellitus(DM),an increasingly prevalent chronic metabolic disease,is characterised by prolonged hyperglycaemia,which leads to long-term health consequences.Although much effort has been put into understanding the pathogenesis of diabetic wounds,the underlying mechanisms remain unclear.The advent of single-cell RNA sequencing(scRNAseq)has revolutionised biological research by enabling the identification of novel cell types,the discovery of cellular markers,the analysis of gene expression patterns and the prediction of develop-mental trajectories.This powerful tool allows for an in-depth exploration of pathogenesis at the cellular and molecular levels.In this editorial,we focus on progenitor-based repair strategies for diabetic wound healing as revealed by scRNAseq and highlight the biological behaviour of various healing-related cells and the alteration of signalling pathways in the process of diabetic wound healing.ScRNAseq could not only deepen our understanding of the complex biology of diabetic wounds but also identify and validate new targets for inter-vention,offering hope for improved patient outcomes in the management of this challenging complication of DM.

Identification and characterization of two morphologically distinct stem cell subpopulations from human urine samples

Urine-derived stem cells(USCs)have shown potentials for the treatment of skeletal and urological disorders.Based on published literature and our own data,USCs consist of heterogeneous populations of cells.In this paper,we identify and characterize two morphologically distinct subpopulations of USCs from human urine samples,named as spindle-shaped USCs(SS-USCs)and rice-shaped USCs(RS-USCs)respectively.The two subpopulations showed similar clone-forming efficiency,while SS-USCs featured faster proliferation,higher motility,and greater potential for osteogenic and adipogenic differentiation,RS-USCs showed greater potential for chondrogenic differentiation.POU5F1 was strongly expressed in both subpopulations,but MYC was weakly expressed.Both subpopulations showed similar patterns of CD24,CD29,CD34,CD44,CD73,CD90 and CD105 expression,while a higher percentage of RS-USCs were positive for CD133.SS-USCs were positive for VIM,weakly positive for SLC12A1 and UMOD,and negative for KRT18,NPHS1,AQP1 and AQP2,indicating a renal mesenchyme origin;while RSUSCs are positive for VIM,partially positive for KRT18,NPHS1,AQP1,SLC12A1 and UMOD,and negative for AQP2,indicating a nephron tubule origin.The above results can facilitate understanding of the biological characteristics of subpopulations of USCs,and provide a basis for further research and applications of such cells.