Dimethyl itaconate alleviates the pyroptosis of macrophages through oxidative stress.

Macrophages are involved in the pathophysiology of many diseases as critical cells of the innate immune system. Pyroptosis is a form of macrophage death that induces cytokinesis of phagocytic substances in the macrophages, thereby defending against infection. Dimethyl itaconate (DI) is an analog of itaconic acid with anti-inflammatory effects. However, the effect of dimethyl itaconate on macrophage pyroptosis has not been elucidated clearly. Thus, the present study aimed to analyze the effect of DI treatment on a macrophage pyroptosis model (Lipopolysaccharide, LPS + Adenosine Triphosphate, ATP). The results showed that 0.25 mM DI ameliorated macrophage pyroptosis and downregulated interleukin (IL)-1ß expression. Then, real-time quantitative polymerase chain reaction (RT-qPCR) was used to confirm the result of RNA-sequencing of the upregulated oxidative stress-related genes (Gclc and Gss) and downregulated inflammation-related genes (IL-12ß and IL-1ß). In addition, Gene Ontology (GO) enrichment analysis showed that differential genes were associated with transcript levels and DNA replication. Kyoto encyclopedia of genes and genomes (KEGG) enrichment showed that signaling pathways, such as tumor necrosis factor (TNF), Jak, Toll-like receptor and IL-17, were altered after DI treatment. N-acetyl-L-cysteine (NAC) reversed the DI effect on the LPS + ATP-induced macrophage pyroptosis and upregulated the IL-1ß expression. Oxidative stress-related protein Nrf2 is involved in the DI regulation of macrophage pyroptosis. Taken together, these findings suggested that DI alleviates the pyroptosis of macrophages through oxidative stress.

Health Effect of Forest Bathing Trip on Elderly Patients with Chronic Obstructive Pulmonary Disease.

Forest bathing trip is a short, leisurely visit to forest. In this study we determined the health effects of forest bathing trip on elderly patients with chronic obstructive pulmonary disease (COPD). The patients were randomly divided into two groups. One group was sent to forest, and the other was sent to an urban area as control. Flow cytometry, ELISA, and profile of mood states (POMS) evaluation were performed. In the forest group, we found a significant decrease of perforin and granzyme B expressions, accompanied by decreased levels of pro-inflammatory cytokines and stress hormones. Meanwhile, the scores in the negative subscales of POMS decreased after forest bathing trip. These results indicate that forest bathing trip has health effect on elderly COPD patients by reducing inflammation and stress level.

Bilirubin influences the predictive effect of body mass index on hospital mortality in critically ill patients.

Introduction: Body mass index (BMI) can predict mortality in critically ill patients. Moreover, mortality is related to increased bilirubin levels. Thus, herein, we aimed to investigate the effect of bilirubin levels on the usefulness of BMI in predicting mortality in critically ill patients. Methods: Data were extracted from the Medical Information Mart for Intensive Care (MIMIC IV) database. Patients were divided into two groups according to their total bilirubin levels within 24 h. Cox proportional hazard regression models were applied to obtain adjusted hazard ratios and 95 % confidence intervals for the correlation between BMI categories and hospital mortality. The dose-response relationship was flexibly modeled using a restricted cubic spline (RCS) with three knots. Results: Of the 14376 patients included, 3.4 % were underweight, 29.3 % were of normal body weight, 32.2 % were overweight, and 35.1 % were obese. For patients with total bilirubin levels <2 mg/dL, hospital mortality was significantly lower in patients with obesity than in normal body weight patients (p < 0.05). However, the opposite results were observed for patients with total bilirubin levels ≥2 mg/dL. The Cox proportional hazard regression models suggested that the risk of death was lower in patients with overweightness and obesity than in normal body weight patients when the total bilirubin levels were <2 mg/dL, but not in the other case (total bilirubin levels ≥2 mg/dL). RCS analyses showed that, for patients with total bilirubin levels <2 mg/dL, the risk of death gradually decreased with increasing BMI. Conversely, for patients with total bilirubin levels ≥2 mg/dL, this risk did not decrease with increasing BMI until reaching obesity, after which it increased rapidly. Conclusion: BMI predicted the risk of death differently in critically ill patients with different bilirubin levels.

4-Octyl itaconate inhibits poly(I:C)-induced interferon-ß secretion in mouse bone marrow-derived macrophages partially by activating Nrf2.

Viruses have become a major threat to human health. Interferon-ß (IFN-ß) has a key role in the antivirus process, as it can increase the expression of antivirus-associated genes. Itaconate and its derivatives can regulate the immune response, secretion of inflammatory factors, and pyroptosis of macrophages. The effect of itaconate on IFN-ß secretion of double-stranded RNA-induced macrophages are not well known. A derivative of itaconate, 4-octoyl itaconate (4-OI), was used to treat mouse bone marrow-derived macrophages (BMDM) induced with 100 µg/mL poly(I:C). The IFN-ß concentration was detected through ELISA, and IFN-ß mRNA expression was detected through quantitative PCR. High-throughput transcriptome sequencing was used to analyze changes in the BMDM transcriptome after 4-OI treatment. The Nrf2 expression was knocked down with siRNA.4-OI inhibited poly(I:C)-induced IFN-ß secretion and mRNA expression in BMDM. Results of transcriptome sequencing revealed that 4-OI downregulated 1047 genes and upregulated 822 genes. GO and KEGG enrichment of differently expressed genes revealed that many downregulated genes were related to the anti-virus process, whereas many upregulated genes were related to metabolism. The Nrf2 inhibitor ML385 and Nrf2 siRNA could partially reverse the inhibitory effect of 4-OI. In conclusion, 4-octyl itaconate could inhibit the poly(I:C)-induced interferon-ß secretion in BMDM partially by regulating Nrf2.

Mesenchymal stem cells support proliferation and terminal differentiation of B cells.

BACKGROUND: Mesenchymal stem cells (MSC) play important roles in modulating the activities of T lymphocytes, dendritic cells and natural killer cells. These immunoregulatory properties of MSC suggest their therapeutic potential in autoimmune diseases. However, the effects of MSC on B cells are still poorly understood. The present study was designed to investigate the interaction between MSC and B cells both in vitro and in vivo, and to determine the possible mechanism of action. DESIGN AND METHOD: The effect of human umbilical cord mesenchymal stem cells (UC-MSC) on proliferation and differentiation of B-cells were characterized in vitro, and we also tested the immunoregulatory properties of mouse bone marrow MSC (BM-MSC) on T cell dependent and independent antibody production in vivo in mice. RESULTS: Treatment with human UC-MSC resulted in an increase of proliferation, differentiation of B cells into plasma cells and production of antibodies in vitro. Mouse BM-MSC significantly enhanced T cell dependent and independent antibodies production in vivo in mice. PGE2 partially mediated the immunosuppressive activity of human UC-MSC but IL-6 did not regulate this activity. CONCLUSION: MSC promote proliferation and differentiation of B cells in vitro and in vivo partially through PGE2 but not IL-6.

IL-6 production stimulated by CD14(+) monocytes-paracrined IL-1ß does not contribute to the immunosuppressive activity of human umbilical cord mesenchymal stem cells.

BACKGROUND/AIMS: Human umbilical cord mesenchymal stem cells (hUC-MSCs) possess immunosuppressive activities but the mechanisms of such activities are not fully understood. Here, we investigated the role of IL-6, one of the characteristic factors of MSCs, in the immunoregulating effect of hUC-MSCs on CD4(+) T lymphocytes. METHODS: The condition media from human peripheral blood mononuclear cells (hPBMCs) or CD14+/- cell were tested if stimulating IL-6 production by hUC-MSCs. The related signaling pathway of IL-6, and the immunosuppressive activity of IL-6 on CD4(+) T lymphocytes were studied. RESULT: IL-6 production was dramatically increased by hUC-MSCs when co-culturing with resting or activated hPBMCs. CD14(+) monocytes-paracrined IL-1ß promoted the secretion of IL-6 by hUC-MSCs via JNK and NF-κB signaling pathway. Blocking of PGE2 synthesis did not affect the secretion of IL-6, anti-IL-6 antibody was not able to reverse hUC-MSCs-mediated inhibition on CD4(+) T lymphocytes. IL-6 did not mediate the suppressive activity of IL-1ß-hUC-MSCs- PGE2 on CD4(+) T cell. CONCLUSION: CD14(+) monocytes-paracrined IL-1ß promotes IL-6 secretion by hUC-MSCs through activating JNK and NF-κB signaling pathway. However, increased IL-6 production does not contribute to immunosuppressive activity of IL-1ß-hUC-MSCs- PGE2 on CD4(+) T cells.

Serum Total Bilirubin Level Is Associated With Hospital Mortality Rate in Adult Critically Ill Patients: A Retrospective Study.

Background: Serum bilirubin level has been suggested to be associated with mortality for patients with severe sepsis. This study aimed to investigate the association of serum total bilirubin level with hospital mortality rate in adult critically ill patients. Method: Data were extracted from the Medical Information Mart for Intensive Care-III (MIMIC-III) database. Patients with measured serum total bilirubin levels that recorded within 24 h after admission were involved in this study. Association of serum total bilirubin level and hospital mortality rate was assessed using logistic regression analysis. Propensity score-matching (PSM) was used to minimize differences between different groups. Results: A total of 12,035 critically ill patients were herein involved. In patients with serum total bilirubin level ≥ 2 mg/dL, the hospital mortality rate was 31.9% compared with 17.0% for patients with serum total bilirubin level < 2 mg/dL (546/1714 vs. 1750/10321, P < 0.001). The results of multivariable logistic regression analysis showed that the odds ratio of mortality in patients with serum total bilirubin level ≥ 2 mg/dL was 1.654 [95% confidence interval (CI): 1.307, 2.093, P < 0.001]. After propensity score matching, in patients with serum total bilirubin level ≥ 2 mg/dL, the weighted hospital mortality rate was 32.2% compared with 24.8% for patients with serum total bilirubin level < 2 mg/dL, P = 0.001). Conclusions: Serum total bilirubin concentration was found to be independently associated with hospital mortality rate in adult critically ill patients.

Macrophages enhance lipopolysaccharide induced apoptosis via Ang1 and NF-κB pathways in human umbilical vein endothelial cells.

Lipopolysaccharide (LPS) could induce apoptosis and dysfunction of endothelial cells. We aimed to reveal the effects of macrophages on cell proliferation and apoptosis in LPS induced human umbilical vein endothelial cells (HUVECs). THP-1 derived macrophages and HUVECs were co-cultured in the presence of LPS. Cell viability was measured by Cell Counting Kit-8 and apoptosis was analyzed by flow cytometry. Expression of Ang1, the NF-κB component p65 was evaluated by western blot and quantitative PCR. Small interfering RNAs (siRNAs) were used to knockdown the expression of proinflammatory cytokines and p65 in HUVECs. Plasmid transfection-mediated overexpression of Ang1 was employed to see its effects on cell proliferation and apoptosis in HUVECs. Macrophages enhanced LPS-induced proliferation impairments and apoptosis in HUVECs, which could be attenuated by siRNA-mediated knockdown of cytokines TNF-α, IL-1ß, IL-6 and IL-12p70 in macrophages. The dysfunction of HUVECs was tightly associated with reduced Ang1 expression and increased phosphorylated p65 (p-65). Overexpression of Ang1 in HUVECs significantly decreased p-p65, suggesting negatively regulation of p-p65 by Ang1. Overexpression of Ang1, adding recombinant Ang1 or silencing of p65 substantially attenuated the dysfunction of HUVECs in terms of cell proliferation and apoptosis. In conclusions, THP-1-derived macrophages enhance LPS induced dysfunction of HUVECs via Ang1 and NF-κB pathways, suggesting new therapeutic targets for sepsis.

IFN-γ induces senescence-like characteristics in mouse bone marrow mesenchymal stem cells.

BACKGROUND: Mesenchymal stem cells (MSC) are considered promising in tissue repair and regeneration medicine due to their proliferation and differentiation ability. Many properties of MSC are affected by cytokines, and IFN-γ has been shown to regulate MSC in many aspects. Senescence affects the proliferation, differentiation and cytokine secretion of MSC. OBJECTIVES: To investigate the effects of IFN-γ on the senescence-associated properties of MSC. MATERIAL AND METHODS: The MSC used in our study were isolated from the bone marrow (BM) of mice. Cell vitalities were measured by CCK8. The phenotypes and ROS of mBM-MSC were analyzed by flow cytometry. Cellular senescence was detected using SA-ß-gal stains. IL-6 and CXCL1 secretions were measured by ELISA. RESULTS: mBM-MSC can differentiated into osteocytes and adipocytes. They expressed CD29, CD106, and Sca-1, and did not express CD31, CD45 or FLK1. Our study showed that the cell vitalities of mBM-MSC were significantly reduced after IFN-γ treatment for 5 days, and the cell numbers were obviously lower after IFN-γ treatment for 5, 10 or 15 days. The IFN-γ group increased SA-ß-gal-positive cells and reactive oxygen species (ROS) significantly after 15 days of IFN-γ treatment. Moreover, IL-6 and CXCL1 secretions were upregulated by IFN-γ. CONCLUSIONS: Our study shows IFN-γ can induce senescence-like characteristics in mBM-MSC, suggesting a novel target for anti-aging therapy.

Human umbilical cord mesenchymal stem cells increase interleukin-9 production of CD4+ T cells.

Mesenchymal stem cells (MSC) are able to differentiate into cells of multiple lineage, and additionally act to modulate the immune response. Interleukin (IL)-9 is primarily produced by cluster of differentiation (CD)4+ T cells to regulate the immune response. The present study aimed to investigate the effect of human umbilical cord derived-MSC (UC-MSC) on IL-9 production of human CD4+ T cells. It was demonstrated that the addition of UC-MSC to the culture of CD4+ T cells significantly enhanced IL-9 production by CD4+ T cells. Transwell experiments suggested that UC-MSC promotion of IL-9 production by CD4+ T cells was dependent on cell-cell contact. Upregulated expression of CD106 was observed in UC-MSC co-cultured with CD4+ T cells, and the addition of a blocking antibody of CD106 significantly impaired the ability of UC-MSC to promote IL-9 production by CD4+ T cells. Therefore, the results of the present study demonstrated that UC-MSC promoted the generation of IL-9 producing cells, which may be mediated, in part by CD106. The findings may act to expand understanding and knowledge of the immune modulatory role of UC-MSC.

Downregulation of miR-146a, cyclooxygenase-2 and advanced glycation end-products in simvastatin-treated older patients with hyperlipidemia.

AIM: Hyperlipidemia is a disease with abnormally elevated levels of lipids/lipoproteins in the blood, and it is regarded as an important risk factor for cardiovascular and cerebrovascular diseases. Statins have been found to prevent vascular diseases by reducing low-density lipoprotein cholesterol and regulation of immune responses. Here, we aim to study the expression change of immune-related microRNA and genes in older patients with hyperlipidemia after treatment with simvastatin. METHODS: A total of 25 older male patients with hyperlipidemia were included in the study and received simvastatin treatment (20 mg/day). Clinical characteristics of these patients were examined, including lipoprotein cholesterol, high-sensitivity C-reactive protein, blood routine and biochemical characters. We tested miR-146a, interleukin-1-receptor-associated kinase 1, tumor necrosis factor-receptor-associated factor 6 and cyclooxygenase-2 level by real-time polymerase chain reaction, and expressions of advanced glycation end-products, p53 and p21 were analyzed by enzyme-linked immunosorbent assay. RESULTS: Simvastatin treatment effectively reduced total cholesterol and low-density lipoprotein cholesterol, but had little effect on high-density lipoprotein cholesterol. High-sensitivity C-reactive protein was slightly reduced. Expression of cyclooxygenase-2 and advanced glycation end-products were significantly reduced. Furthermore, simvastatin effectively reduced the expression of p53 and p21. Significantly downregulated miR-146a, and an obvious reduction of interleukin-1-receptor-associated kinase 1 were also detected, whereas tumor necrosis factor-receptor-associated factor 6 remained unchanged. Besides, there was a significant reduction of alanine transaminase, aspertate aminotransferase, alkaline phosphatase and lactate dehydrogenase. CONCLUSION: Simvastatin treatment could inhibit inflammation and senescence-associated genes in older patients with hyperlipidemia, suggesting its application in inflammatory and age-related diseases.

Heterogeneity of proangiogenic features in mesenchymal stem cells derived from bone marrow, adipose tissue, umbilical cord, and placenta.

BACKGROUND: Mesenchymal stem cells (MSCs) have been widely proven effective for therapeutic angiogenesis in ischemia animal models as well as clinical vascular diseases. Because of the invasive method, limited resources, and aging problems of adult tissue-derived MSCs, more perinatal tissue-derived MSCs have been isolated and studied as promising substitutable MSCs for cell transplantation. However, fewer studies have comparatively studied the angiogenic efficacy of MSCs derived from different tissues sources. Here, we evaluated whether the in-situ environment would affect the angiogenic potential of MSCs. METHODS: We harvested MSCs from adult bone marrow (BMSCs), adipose tissue (AMSCs), perinatal umbilical cord (UMSCs), and placental chorionic villi (PMSCs), and studied their "MSC identity" by flow cytometry and in-vitro trilineage differentiation assay. Then we comparatively studied their endothelial differentiation capabilities and paracrine actions side by side in vitro. RESULTS: Our data showed that UMSCs and PMSCs fitted well with the minimum standard of MSCs as well as BMSCs and AMSCs. Interestingly, we found that MSCs regardless of their tissue origins could develop similar endothelial-relevant functions in vitro, including producing eNOS and uptaking ac-LDL during endothelial differentiation in spite of their feeble expression of endothelial-related genes and proteins. Additionally, we surprisingly found that BMSCs and PMSCs could directly form tubular structures in vitro on Matrigel and their conditioned medium showed significant proangiogenic bioactivities on endothelial cells in vitro compared with those of AMSCs and UMSCs. Besides, several angiogenic genes were upregulated in BMSCs and PMSCs in comparison with AMSCs and UMSCs. Moreover, enzyme-linked immunosorbent assay further confirmed that BMSCs secreted much more VEGF, and PMSCs secreted much more HGF and PGE2. CONCLUSIONS: Our study demonstrated the heterogeneous proangiogenic properties of MSCs derived from different tissue origins, and the in vivo isolated environment might contribute to these differences. Our study suggested that MSCs derived from bone marrow and placental chorionic villi might be preferred in clinical application for therapeutic angiogenesis.

[IL-1ß promotes the hematopoietic support of human umbilical cord mesenchymal stem cells].

This study was aimed to investigate the effect of IL-1ß on hematopoietic support of human umbilical cord mesenchymal stem cells (hUC-MSC). 2×10(6) hUC-MSC were seeded in 75 cm(2) flasks, after adherence to wall for 2 h, 10 ng/ml IL-1ß was added in hUC-MSC supernatant and cultured for 36 h, then the culture supernatants and cells were harvested. The effect of conditioned medium with/without IL-1ß on CD34(+) cell hematopoietic support was observed, mRNA expression changes of hUC-MSC cultured in medium with/without IL-1ß were monitored by real time PCR, the differences in hematopoiesis-related factors were detected by ELISA. The results showed that the conditioned culture medium of hUC-MSC with IL-1ß enhanced the ability to form colony of CD34(+) cells, especially CFU-G and CFU-GM in vitro; IL-1ß promoted the mRNA expression of GM-CSF, G-CSF, IL-6 on MSC; IL-1ß also promoted the secretion of GM-CSF, G-CSF, and IL-6 protein from hUC-MSC. It is concluded that IL-1ß enhances hematopoietic support capacity especially, capability of MSC to myeloid differentiation.

[Isolation and biological characteristics of mesenchymal stem cells derived from human placenta decidua basalis].

Comparing to bone marrow mesenchymal stem cells (MSCs), placenta-derived MSCs have the advantages of adequate sources, low immunogenicity, little risk of viral contamination, and no ethical controversy, and thus possess a better prospect for clinical application. Placental tissue not only includes chorionic and amniotic, but also contains decidua basalis which locate in the maternal placenta surface. The biological characteristics of MSCs isolated from decidua basalis have not been well studied. This study was aimed to investigate the biologic characteristics of placenta decidua basalis-derived MSC from placenta decidua basalis (DB) by enzymatic digestion. Short tandem repeats (STR) test was used to identify the cells derived from the maternal placenta surface. Growth rate of decidua basalis mesenchymal stem cells (DB-MSC) was measured by MTT. Cell cycle and cell phenotype were detected by flow cytometry. Inducing differentiation was used to evaluate multipotency of DB-MSC. For testing the immunosuppression of DB-MSC, they were co-cultured with peripheral blood mononuclear cells (PBMNC) stimulated by phytohemagglutinin (PHA) and then IFN-γ in the co-cultured media was quantified by ELISA. The results showed that the cells were derived from the maternal placenta by STR analysis. DB-MSC showed typical fibroblast morphology in the culture and were positive for the MSC surface markers: CD90, CD73, CD105, CD44 and negative for CD45, CD11b, and CD34. DB-MSC underwent osteogenic, adipogenic and chondrogenic differentiation in inducing medium. DB-MSC could inhibit the secretion of IFN-γ by PBMNC. It is concluded that the cells are isolated from placenta decidua basalis and possess the basic characteristics of MSC. DB-MSC can be an important maternal autologous MSC and may be a safe and effective treatment for immune system diseases, which makes the DB-MSC as an important source of autologous MSC from mother. DB-MSC can be safely for the treatment of the mother's immune system diseases.

[Long term in-vitro expansion reduces immune modulation function of placental chorionic villi mesenchymal stem cells].

The main aim of this study was to investigate the biological activities and immune modulation changes of chorionic villi mesenchymal stem cells (CV-MSC) after long term culture. The morphology of the CV-MSC of passage 3 and passage 9 were observed by microscopy, and their phenotypes were detected by flow cytometry. CV-MSC of passage 3 and 9 were co-cultured with PHA-stimulated PBMNC, and IFN-γ concentration in culture medium was detected by ELISA. The mRNA expression of COX-2, HGF and HLA-G in CV-MSC were detected by real-time PCR. The results showed that after long term culture, the CV-MSC kept the MSC morphology and most of the phenotypes including CD31, CD34, CD44, CD45, CD62L, CD73, CD90, CD105, CD117, CD151, CD235a, CD271 and HLA-DR, while the CD49d was significantly up-regulated. Immune modulation ability of CV-MSC was reduced and the mRNA expression of COX-2 and HGF was down regulated after long term culture, but the expression of HLA-G did not found to be obvious change. It is concluded that the long term in vitro expansion changes the expression of CD49d and reduces immune modulation of CV-MSC.

CD106 identifies a subpopulation of mesenchymal stem cells with unique immunomodulatory properties.

Mesenchymal stem cells (MSCs) reside in almost all of the body tissues, where they undergo self-renewal and multi-lineage differentiation. MSCs derived from different tissues share many similarities but also show some differences in term of biological properties. We aim to search for significant differences among various sources of MSCs and to explore their implications in physiopathology and clinical translation. We compared the phenotype and biological properties among different MSCs isolated from human term placental chorionic villi (CV), umbilical cord (UC), adult bone marrow (BM) and adipose (AD). We found that CD106 (VCAM-1) was expressed highest on the CV-MSCs, moderately on BM-MSCs, lightly on UC-MSCs and absent on AD-MSCs. CV-MSCs also showed unique immune-associated gene expression and immunomodulation. We thus separated CD106(+)cells and CD106(-)cells from CV-MSCs and compared their biological activities. Both two subpopulations were capable of osteogenic and adipogenic differentiation while CD106(+)CV-MSCs were more effective to modulate T helper subsets but possessed decreased colony formation capacity. In addition, CD106(+)CV-MSCs expressed more cytokines than CD106(-)CV-MSCs. These data demonstrate that CD106 identifies a subpopulation of CV-MSCs with unique immunoregulatory activity and reveal a previously unrecognized mechanism underlying immunomodulation of MSCs.

[Supportive effects of conditioned culture media of human umbilical cord mesenchymal stem cells on hematopoiesis in vitro].

This study was aimed to explore whether the conditioned culture medium of human umbilical cord-derived mesenchymal stem cells (hUC-MSC) has supportive effects on hematopoiesis in vitro. hUC-MSC were cultured in 75 cm(2) culture flasks at a concentration of 2×10(6) cells per flask. After 48 h, the conditioned culture medium was harvested. CD34(+) cells were isolated with the human cord blood CD34 positive selection kit. The CD34(+) cells were plated in three different culture systems: the culture supernatant from hUC-MSC added into incomplete methylcellulose without recombinant human cytokines as conditioned culture medium; the complete methylcellulose medium with recombinant human cytokines as positive control medium; incomplete methylcellulose adding DMEM/F12 with 10% FBS instead of conditioned culture medium as the negative control medium. After 14 days of culture, colonies containing ≥ 50 cells were scored and types of colonies were classified under inverted microscope. The immunophenotypes of cells which were collected from the colonies were detected by flow cytometry. The results showed that conditioned culture medium of hUC-MSC supported the differentiation of CD34(+) cells into CFU-G (47.67 ± 0.58), CFU-GM (48.67 ± 4.73) and CFU-M (3.00 ± 2.00) in vitro, while the CFU-E, BFU-E or CFU-GEMM were absent. Comparatively, in the positive control medium all kinds of CFU were observed. Interestingly, the percentage of CD45(+)cells of CFU in conditioned culture medium (97.43 ± 2.15)% was more than CD45(+)cells in positive control medium (39.69 ± 0.96)% (P < 0.05). It is concluded that the conditioned culture medium of hUC-MSC has been confirmed to have ability to support hematopoiesis separately in vitro. Besides, it enhances the differentiation of CD34(+) cells into myeloid cells except cells of erythroid lineage.

[Comparative study of biological characteristics of human umbilical cord and placental chorionic villous mesenchymal stem cells].

Because advantage of tissue origin and proliferation potential, the umbilical cord-derived mesenchymal stem cells (UC-MSC) and placental chorionic villous-derived mesenchymal stem cells (CV-MSC) have clinical application potential, as compared with bone marrow MSC. But whether the differences of biological characteristics exist between UC-MSC and CV-MSC, which deserve to be further explored. This study was purposed to compare the biological characteristics of UC-MSC and CV-MSC. The placental and umbilical cord were cleaned by using the sterile physiological salt, the UC-MSC and CV-MSC were separated by enzyme digestion. Short tandem repeat (STR) analysis was used to detect whether the MSC obtained from fetal tissue. MTT method was used to detect proliferation of MSC. Flow cytometry was applied to analyze cell phenotype. The different differential medium was used to detect their multi-directional differentiation capacity. After the MSC and PHA-stimulated peripheral blood mononuclear cells were co-cultured, the γ-interferon (IFN-γ) levels of the co-culture supernatant were detected using the ELISA. The results showed that these MSC were derived from fetal tissue by STR analysis. They were adherent cells with typical fibroblast morphology. Cells expressed the MSC surface markers CD90, CD73 and CD105 and CD44, not expressed CD45 and of CD11b and CD34.These cells could differentiate into osteoblasts and adipoblasts under culture with different conditioned medium, but in the adipogenic differentiation of CV-MSC, the larger lipid droplets appeared. It is concluded that these cells are obtained MSC. These MSC can inhibit peripheral blood mononuclear cells stimulated by PHA to secrete IFN-γ, and the the CV-MSC have a stronger suppression capacity, which makes the CV-MSC to have a greater advantage in the treatment of autoimmune diseases.