共查询到20条相似文献,搜索用时 31 毫秒
1.
The Notochord, Notochordal cell and CTGF/CCN-2: ongoing activity from development through maturation
W. Mark Erwin 《Journal of cell communication and signaling》2008,2(3-4):59-65
The growth regulating factor CTGF/CCN-2 is an integral factor in growth and development, connective tissue maintenance, wound repair and cell cycle regulation. It has recently been reported that CTGF/CCN-2 is involved in very early development having been detected in early notochord formation in zebrafish using CTGF/CCN-2 promoter-driven green fluorescent protein (GFP) plasmids. In these studies fluorescence was detected early in the developing embryos, a finding of considerable significance in that CTGF/CCN-2 deficient mutant mice die early after birth due to severe cartilage and skeletal dysplasia and respiratory failure. Such findings confirm the importance of CTGF/CCN-2 in development and of the necessary and sufficient role of this molecule in formation of the skeleton, extracellular matrix and chondrogenesis. Of particular relevance to the relationship between the notochordal cell and CTGF/CCN-2 there is a remarkable sub-species of canine, the ‘non-chondrodystrophic’ canine that is protected from developing degenerative disc disease (DDD). These animals are unique in that they preserve the population of notochordal cells within their disc nucleus (NP) and these cells secrete CTGF/CCN-2. We have detected CTGF/CCN-2 within conditioned medium developed from the notochordal cells of these animals (NCCM) and used this conditioned medium to demonstrate robustly increased proteoglycan production. The addition of recombinant human CTGF/CCN-2 to totally serum-free media containing cultures of bovine NP cells replicated the robustly increased aggrecan gene expression found with NCCM alone strongly suggesting the importance of the effect of CTGF/CCN-2 in notochordal cell biology within the disc nucleus of non-chondrodystrophic canines. The chondrodystrophic canine, another sub-species on the other hand are almost totally devoid of notochordal cells and they develop DDD profoundly and early. These two sub-species of canine reflect a naturally occurring animal model that is an excellent example of differential notochordal cell survival and possible associated developmental differences in extracellular maintenance. 相似文献
2.
Michaela Leyh Andreas Seitz Lutz Dürselen Jens Schaumburger Anita Ignatius Joachim Grifka Susanne Gr?ssel 《Arthritis research & therapy》2014,16(5)
Introduction
Osteoarthritis (OA) is characterized by an imbalance in cartilage and underlying subchondral bone homeostasis. We hypothesized that signals from the subchondral bone may modulate production of matrix components, alter chondrogenic differentiation potential of cocultured bone marrow-derived mesenchymal stem cells (BMSC) and induce a phenotypic shift in differentiated OA chondrocytes.Methods
We established a novel coculture model between BMSC, mixed cultures (BMSC and chondrocytes) and chondrocytes embedded in fibrin gel with OA and normal subchondral bone explants (OAB and NB). Tissues and cells were either derived from OA or trauma patients. In addition, we used adipose-derived stem cells (ASC) from liposuction. With gene expression analysis, biochemical assays, immunofluorescence and biomechanical tests we characterized the properties of newly generated extracellular matrix (ECM) from chondrocytes and chondrogenically differentiating BMSC cocultured with OAB or NB in comparison with monocultures (cultures without bone explants).Results
Overall, gene expression of collagens of OAB and NB cocultured cells was reduced compared to monocultures. Concomitantly, we observed significantly lower collagen I, II and III and glycosaminoglycan (GAG) production in OAB cocultured cell lysates. In parallel, we detected increased concentrations of soluble GAGs and basic fibroblast growth factor (bFGF), interleukin (IL)-6 and IL-8 in supernatants of OAB and NB cocultures mainly at early time points. IL-1ß concentration was increased in supernatants of OAB cocultures, but not in NB cocultures. Cell-free NB or OAB explants released different amounts of IL-1ß, bFGF and soluble GAG into cell culture supernatants. In comparison to cocultures, monocultures exhibited higher Young’s modulus and equilibrium modulus. Stimulation of monocultures with IL-1ß led to a downregulation of aggrecan (ACAN) gene expression and in general to induced matrix metalloprotease (MMP)2, MMP3 and MMP-13 gene expression while IL-6 and IL-8 stimulation partly reduced ACAN, MMP3 and MMP-13 gene expression.Conclusions
Our results suggest an alteration of molecular composition and mechanical properties of the newly formed ECM in subchondral bone cocultures. We suggest that soluble factors, that is interleukins and bFGF, released in cocultures exert inhibitory effects on collagen and temporary effects on proteoglycan production, which finally results in a reduction of mechanical strength of newly formed fibrillar networks.Electronic supplementary material
The online version of this article (doi:10.1186/s13075-014-0453-9) contains supplementary material, which is available to authorized users. 相似文献3.
Zhuochao Liu Zhiyong Zheng Jin Qi Jun Wang Qi Zhou Fangqiong Hu Jing Liang Changwei Li Weibin Zhang Xingkai Zhang 《Journal of biological engineering》2018,12(1):35
Background
Cell-based therapy by transplantation of nucleus pulposus (NP) progenitor/notochordal cells has been proposed as a promising way to halt and reverse the progression of disc degeneration. Although some studies have provided a broad panel of potential markers associated with the phenotype of notochordal cells, suitability of these markers for isolation of notochordal cells for the treatment of disc degeneration is unclear.Results
Here, we found that the number of CD24-positive NP cells significantly decreased with increasing severity of disc degeneration. In addition, CD24-positive NP cells were shown to maintain their multipotent differentiation and self-renewal potential in vitro and to abundantly express brachyury, SHH, and GLUT-1, suggesting that CD24-positive NP cells are the progenitor/notochordal cells in the NP. Moreover, our in vivo experiments revealed that transplantation of CD24-positive NP cells enables the recovery of degenerate discs, as evidenced by increased disc height, restored magnetic resonance imaging T2-weighted signal intensity, and NP structure. In terms of the mechanism, HIF-1α–Notch1 pathway activation was essential for the maintenance of CD24-positive NP cells.Conclusion
Our studies identify that CD24-positive NP cells are the resident progenitor/notochordal cells in disc regeneration and elucidate a crucial role of HIF-1α–Notch1 pathway in the phenotypic maintenance of CD24-positive NP cells.4.
Glycogen synthase kinase 3beta contributes to proliferation of arterial smooth muscle cells in pulmonary hypertension 总被引:1,自引:0,他引:1
Sklepkiewicz P Schermuly RT Tian X Ghofrani HA Weissmann N Sedding D Kashour T Seeger W Grimminger F Pullamsetti SS 《PloS one》2011,6(4):e18883
Rationale
Pulmonary arterial hypertension (PAH) is a rare progressive pulmonary vascular disorder associated with vascular remodeling and right heart failure. Vascular remodeling involves numerous signaling cascades governing pulmonary arterial smooth muscle cell (PASMC) proliferation, migration and differentiation. Glycogen synthase kinase 3beta (GSK3ß) is a serine/threonine kinase and can act as a downstream regulatory switch for numerous signaling pathways. Hence, we hypothesized that GSK3ß plays a crucial role in pulmonary vascular remodeling.Methods
All experiments were done with lung tissue or isolated PASMCs in a well-established monocrotaline (MCT)-induced PAH rat model. The mRNA expression of Wnt ligands (Wnt1, Wnt3a, Wnt5a), upstream Wnt signaling regulator genes (Frizzled Receptors 1, 2 and secreted Frizzled related protein sFRP-1) and canonical Wnt intracellular effectors (GSK3ß, Axin1) were assessed by real-time polymerase chain reaction and protein levels of GSK3ß, phospho-GSK3ß (ser 9) by western blotting and localization by immunohistochemistry. The role of GSK3ß in PASMCs proliferation was assessed by overexpression of wild-type GSK3ß (WT) and constitutively active GSK3ß S9A by [3H]-thymidine incorporation assay.Results
Increased levels of total and phosphorylated GSK3ß (inhibitory phosphorylation) were observed in lungs and PASMCs isolated from MCT-induced PAH rats compared to controls. Further, stimulation of MCT-PASMCs with growth factors induced GSK3ß inactivation. Most importantly, treatment with the PDGFR inhibitor, Imatinib, attenuated PDGF-BB and FCS induced GSK3ß phosphorylation. Increased expression of GSK3ß observed in lungs and PASMC isolated from MCT-induced PAH rats was confirmed to be clinically relevant as the same observation was identified in human iPAH lung explants. Overexpression of GSK3ß significantly increased MCT-PASMCs proliferation by regulating ERK phosphorylation. Constitutive activation of GSK3ß (GSK3ß S9A, 9th serine replaced to alanine) inhibited MCT-PASMCs proliferation by decreasing ERK phosphorylation.Conclusion
This study supports a central role for GSK3ß in vascular remodeling processes and suggests a novel therapeutic opportunity for the treatment of PAH. 相似文献5.
6.
Background/Objectives
Ambient air pollution can alter cytokine concentrations as shown in vitro and following short-term exposure to high air pollution levels in vivo. Exposure to pollution during late pregnancy has been shown to affect fetal lymphocytic immunophenotypes. However, effects of prenatal exposure to moderate levels of air pollutants on cytokine regulation in cord blood of healthy infants are unknown.Methods
In a birth cohort of 265 healthy term-born neonates, we assessed maternal exposure to particles with an aerodynamic diameter of 10 µm or less (PM10), as well as to indoor air pollution during the last trimester, specifically the last 21, 14, 7, 3 and 1 days of pregnancy. As a proxy for traffic-related air pollution, we determined the distance of mothers'' homes to major roads. We measured cytokine and chemokine levels (MCP-1, IL-6, IL-10, IL-1ß, TNF-α and GM-CSF) in cord blood serum using LUMINEX technology. Their association with pollution levels was assessed using regression analysis, adjusted for possible confounders.Results
Mean (95%-CI) PM10 exposure for the last 7 days of pregnancy was 18.3 (10.3–38.4 µg/m3). PM10 exposure during the last 3 days of pregnancy was significantly associated with reduced IL-10 and during the last 3 months of pregnancy with increased IL-1ß levels in cord blood after adjustment for relevant confounders. Maternal smoking was associated with reduced IL-6 levels. For the other cytokines no association was found.Conclusions
Our results suggest that even naturally occurring prenatal exposure to moderate amounts of indoor and outdoor air pollution may lead to changes in cord blood cytokine levels in a population based cohort. 相似文献7.
Lambert JC Dallongeville J Ellis KA Schraen-Maschke S Lui J Laws S Dumont J Richard F Cottel D Berr C Ames D Masters CL Rowe CC Szoeke C Tzourio C Dartigues JF Buée L Martins R Amouyel P 《PloS one》2011,6(4):e18536
Background
Aß peptides are often considered as catabolic by-products of the amyloid ß protein precursor (APP), with unknown physiological functions. However, several biological properties have been tentatively attributed to these peptides, including a role in vasomotion.We assess whether plasma Aß peptide levels might be associated with systolic and diastolic blood pressure values (SBP and DBP, respectively).Methodology/Principal Findings
Plasma Aß1-40 and Aß1-42 levels were measured using an xMAP-based assay in 1,972 individuals (none of whom were taking antihypertensive drugs) from 3 independent studies: the French population-based 3C and MONA-LISA (Lille) studies (n = 627 and n = 769, respectively) and the Australian, longitudinal AIBL study (n = 576). In the combined sample, the Aß1-42/ Aß1-40 ratio was significantly and inversely associated with SBP (p = 0.03) and a similar trend was observed for DBP (p = 0.06). Using the median age (69) as a cut-off, the Aß1-42/Aß1-40 ratio was strongly associated with both SBP and DBP in elderly individuals (p = 0.002 and p = 0.03, respectively). Consistently, a high Aß1-42/ Aß1-40 ratio was associated with a lower risk of hypertension in both the combined whole sample (odds ratio [OR], 0.71; 95% confidence interval [CI], 0.56-0.90) and (to an even greater extent) in the elderly subjects (OR, 0.53; 95% CI, 0.37–0.75). Lastly, all these associations appeared to be primarily driven by the level of plasma Aß1-40.Conclusion
The plasma Aß1-42/Aß1-40 ratio is inversely associated with SBP, DBP and the risk of hypertension in elderly subjects, suggesting that Aß peptides affect blood pressure in vivo. These results may be particularly relevant in Alzheimer''s disease, in which a high Aß1-42/Aß1-40 plasma ratio is reportedly associated with a decreased risk of incident disease. 相似文献8.
Wang CQ Cruz-Inigo AE Fuentes-Duculan J Moussai D Gulati N Sullivan-Whalen M Gilleaudeau P Cohen JA Krueger JG 《PloS one》2011,6(4):e18907
Background
Vitiligo is a common skin disorder, characterized by progressive skin de-pigmentation due to the loss of cutaneous melanocytes. The exact cause of melanocyte loss remains unclear, but a large number of observations have pointed to the important role of cellular immunity in vitiligo pathogenesis.Methodology/Principal Findings
In this study, we characterized T cell and inflammation-related dermal dendritic cell (DC) subsets in pigmented non-lesional, leading edge and depigmented lesional vitiligo skin. By immunohistochemistry staining, we observed enhanced populations of CD11c+ myeloid dermal DCs and CD207+ Langerhans cells in leading edge vitiligo biopsies. DC-LAMP+ and CD1c+ sub-populations of dermal DCs expanded significantly in leading edge and lesional vitiligo skin. We also detected elevated tissue mRNA levels of IL-17A in leading edge skin biopsies of vitiligo patients, as well as IL-17A positive T cells by immunohistochemistry and immunofluorescence. Langerhans cells with activated inflammasomes were also noted in lesional vitiligo skin, along with increased IL-1ß mRNA, which suggest the potential of Langerhans cells to drive Th17 activation in vitiligo.Conclusions/Significance
These studies provided direct tissue evidence that implicates active Th17 cells in vitiligo skin lesions. We characterized new cellular immune elements, in the active margins of vitiligo lesions (e.g. populations of epidermal and dermal dendritic cells subsets), which could potentially drive the inflammatory responses. 相似文献9.
Benjamin Wilde Marielle Thewissen Jan Damoiseaux Marc Hilhorst Pieter van Paassen Oliver Witzke Jan Willem Cohen Tervaert 《Arthritis research & therapy》2012,14(5):R227
Introduction
In autoimmune diseases, IL-17 producing T-cells (Th17), a pro-inflammatory subset of T-cells, are pathophysiologically involved. There is little knowledge on the role of Th17 cells in granulomatosis with polyangiitis (GPA). In the present study, we investigated Th17 cells, Tregs and subsets of circulating Th17 cells in GPA and related results to disease activity.Methods
42 GPA patients in remission, 18 with active disease and 14 healthy controls (HC) were enrolled. Th17 cells, their subsets and regulatory T-cells were determined by intracellular fluorescence activated cell sorter (FACS). Data are given as mean percentage ±SD of total T-helper-cells.Results
Th17 cells are expanded in active and quiescent GPA as compared to HC (1.7±1.4% vs. 0.7 ±0.3%, P = 0.006 and 1.9 ±1.5% vs. 0.7 ±0.3%, P<0.0001). Th17 expansion is stable over time and does not decline when remission is achieved. However, a negative association of Th17 cells and steroid dosage is observed (r=-0.46, P = 0.002). The Th17 expansion was not balanced by Tregs as indicated by skewed Th17/Treg ratios in active and quiescent GPA. Th17 subsets co-producing IFNγ or IL-10 are significantly increased in GPA. GPA patients in remission not receiving maintenance therapy have significantly more IL-10/IL-17A double positive T-cells than HC (0.0501 ±0.031% vs. 0.0282 ±0.016%, P = 0.007).Conclusions
We provide evidence for a persistent, unbalanced expansion of Th17 cells and Th17 subsets which seems to be independent of disease activity. Maintenance therapy reduces -but does not normalize- Th17 expansion. 相似文献10.
Valva P Casciato P Diaz Carrasco JM Gadano A Galdame O Galoppo MC Mullen E De Matteo E Preciado MV 《PloS one》2011,6(8):e23218
Background/Aims
Liver biopsy represents the gold standard for damage evaluation, but noninvasive serum markers that mirror liver fibrosis progression are actual goals both in adults and especially in children. The aim was to determine specific serum markers that correlate with liver fibrosis progression during chronic HCV infection.Methods
Liver biopsies and concomitant serum samples from 22 pediatric and 22 adult HCV patients were analyzed. Histological parameters were evaluated. On serum TGF-ß1, tissue inhibitor of matrix metalloprotein inhibitor-1 (TIMP-1), hyaluronic acid (HA) and aminoterminal peptide of procollagen type III (PIIINP) were tested.Results
Significant fibrosis (F≥2) and advanced fibrosis (F≥3) represented 64% and 20%, respectively in children; while 54% F≥2 and 23% F≥3 in adults. Hyaluronic acid (p = 0.011) and PIIINP (p = 0.016) were related to worse fibrosis stages only in adults, along with TIMP-1 (p = 0.039) just in children; but TGF-ß1 was associated with mild fibrosis (p = 0.022) in adults. The AUROC of TIMP-1 in children to discriminate advanced fibrosis was 0.800 (95%IC 0.598–0.932). In adults, the best AUROCs were that of HA, PIIINP and TGF-ß1 [0.929 (IC95% 0.736–0.994), 0.894 (IC95% 0.689–0.984) and 0.835 (IC95% 0.617–0.957)], respectively. In children, according to the cut off (165.7 ng/mL) value for TIMP-1, biopsies could have been avoided in 72% (18/25). Considering the cut off for HA (109.7 ng/mL), PIIINP (9.1 µg/L), and TGF-ß1 (10,848.3 pg/mL), biopsies could have been avoided in 87% (19/22) of adult patients by using HA and 73% (16/22) using PIIINP or TGF-ß1.Conclusions
In adults given the diagnostic accuracy of HA, PIIINP, TGF-ß1, their combination may provide a potential useful tool to assess liver fibrosis. This first pediatric study suggests that TIMP-1 is clinically useful for predicting liver fibrosis in HCV patients. 相似文献11.
Devina Purmessur Clare C Guterl Samuel K Cho Marisa C Cornejo Ying W Lam Bryan A Ballif Damien M Laudier James C Iatridis 《Arthritis research & therapy》2013,15(5):R122
Introduction
Notochordal cells (NCs) pattern aneural and avascular intervertebral discs (IVDs), and their disappearance, is associated with onset of IVD degeneration. This study induced and characterized the maturation of nucleus pulposus (NP) tissue from a gelatinous NC-rich structure to a matrix-rich structure populated by small NP cells using dynamic pressurization in an ex vivo culture model, and also identified soluble factors from NCs with therapeutic potential.Methods
Porcine NC-rich NP tissue was cultured and loaded with hydrostatic pressure (0.5 to 2 MPa at 0.1 Hz for 2 hours) either Daily, for 1 Dose, or Control (no pressurization) groups for up to eight days. Cell phenotype and tissue maturation was characterized with measurements of cell viability, cytomorphology, nitric oxide, metabolic activity, matrix composition, gene expression, and proteomics.Results
Daily pressurization induced transition of NCs to small NP cells with 73.8%, 44%, and 28% NCs for Control, 1 Dose and Daily groups, respectively (P < 0.0002) and no relevant cell death. Dynamic loading matured NP tissue by significantly increasing metabolic activity and accumulating Safranin-O-stained matrix. Load-induced maturation was also apparent from the significantly decreased glycolytic, cytoskeletal (Vimentin) and stress-inducible (HSP70) proteins assessed with proteomics. Loading increased the production of bioactive proteins Sonic Hedgehog (SHH) and Noggin, and maintained Semaphorin3A (Sema3A).Discussion
NP tissue maturation was induced from dynamic hydrostatic pressurization in a controlled ex vivo environment without influence from systemic effects or surrounding structures. NCs transitioned into small nonvacuolated NP cells probably via differentiation as evidenced by high cell viability, lack of nitric oxide and downregulation of stress-inducible and cytoskeletal proteins. SHH, Sema3A, and Noggin, which have patterning and neurovascular-inhibiting properties, were produced in both notochordal and matured porcine NP. Results therefore provide an important piece of evidence suggesting the transition of NCs to small NP cells is a natural part of aging and not the initiation of degeneration. Bioactive candidates identified from young porcine IVDs may be isolated and harnessed for therapies to target discogenic back pain. 相似文献12.
Background
The role of IL-17 producing cells in tumors is controversial. In the present study, we investigated the prognostic value of measuring tumor-infiltrating IL-17 producing cell levels in human esophageal squamous cell carcinoma (ESCC).Methodology/Principal Findings
Immunohistochemical staining was performed to investigate the levels of IL-17+ tumor infiltrating lymphocytes (TILs), as well as CD8+ cytotoxic T lymphocytes (CTLs) and CD57+ natural killer (NK) cells from 181 ESCC patients. The prognostic value of measuring the densities of IL-17+TILs and the correlation with CTLs and NK was evaluated. IL-17 producing cells were detected in esophageal squamous cell carcinoma tissues. The IL-17 producing cells were major CD4 positive, but Foxp3 negative. The median level of IL-17+TILs was 3.90 cells/high power microscopic field (HPF). The density of IL-17 producing cells correlated negatively with T stage (P = 0.042). The higher densities of tumor infiltrating IL-17+ lymphocytes were associated with better overall survival (P = 0.031). Furthermore, we found that there were positive correlations between levels of IL-17 producing cells and the densities of CD8+cells, as well as CD57+cells (r = 0.198, P = 0.008 for CD8+ cells and r = 0.261, P<0.001 for CD57+ cells, respectively). The prognosis analysis also showed that the higher levels of CD8+ CTLs and CD57+ NK cells correlated with better overall survival of ESCC patients.Conclusions
Our study suggests that tumor infiltrating IL-17 producing cells in ESCC patients may have protective roles in the tumor microenvironment and may be treated as a prognostic marker for ESCC patients. 相似文献13.
Sbiera S Dexneit T Reichardt SD Michel KD van den Brandt J Schmull S Kraus L Beyer M Mlynski R Wortmann S Allolio B Reichardt HM Fassnacht M 《PloS one》2011,6(9):e24345
Background
Pre- and early clinical studies on patients with autoimmune diseases suggested that induction of regulatory T(Treg) cells may contribute to the immunosuppressive effects of glucocorticoids(GCs).Objective
We readdressed the influence of GC therapy on Treg cells in immunocompetent human subjects and naïve mice.Methods
Mice were treated with increasing doses of intravenous dexamethasone followed by oral taper, and Treg cells in spleen and blood were analyzed by FACS. Sixteen patients with sudden hearing loss but without an inflammatory disease received high-dose intravenous prednisolone followed by stepwise dose reduction to low oral prednisolone. Peripheral blood Treg cells were analyzed prior and after a 14 day GC therapy based on different markers.Results
Repeated GC administration to mice for three days dose-dependently decreased the absolute numbers of Treg cells in blood (100 mg dexamethasone/kg body weight: 2.8±1.8×104 cells/ml vs. 33±11×104 in control mice) and spleen (dexamethasone: 2.8±1.9×105/spleen vs. 95±22×105/spleen in control mice), which slowly recovered after 14 days taper in spleen but not in blood. The relative frequency of FOXP3+ Treg cells amongst the CD4+ T cells also decreased in a dose dependent manner with the effect being more pronounced in blood than in spleen. The suppressive capacity of Treg cells was unaltered by GC treatment in vitro. In immunocompetent humans, GCs induced mild T cell lymphocytosis. However, it did not change the relative frequency of circulating Treg cells in a relevant manner, although there was some variation depending on the definition of the Treg cells (FOXP3+: 4.0±1.5% vs 3.4±1.5%*; AITR+: 0.6±0.4 vs 0.5±0.3%, CD127low: 4.0±1.3 vs 5.0±3.0%* and CTLA4+: 13.8±11.5 vs 15.6±12.5%; * p<0.05).Conclusion
Short-term GC therapy does not induce the hitherto supposed increase in circulating Treg cell frequency, neither in immunocompetent humans nor in mice. Thus, it is questionable that the clinical efficacy of GCs is achieved by modulating Treg cell numbers. 相似文献14.
Background
Aberrant CD40 ligand (CD154) expression occurs on both T cells and B cells in human lupus patients, which is suggested to enhance B cell CD40 signaling and play a role in disease pathogenesis. Transgenic mice expressing CD154 by their B cells (CD154TG) have an expanded spleen B cell pool and produce autoantibodies (autoAbs). CD22 deficient (CD22−/−) mice also produce autoAbs, and importantly, their B cells are hyper-proliferative following CD40 stimulation ex vivo. Combining these 2 genetic alterations in CD154TGCD22−/− mice was thereby predicted to intensify CD40 signaling and autoimmune disease due to autoreactive B cell expansion and/or activation.Methodology/Principal Findings
CD154TGCD22−/− mice were assessed for their humoral immune responses and for changes in their endogenous lymphocyte subsets. Remarkably, CD154TGCD22−/− mice were not autoimmune, but instead generated minimal IgG responses against both self and foreign antigens. This paucity in IgG isotype switching occurred despite an expanded spleen B cell pool, higher serum IgM levels, and augmented ex vivo B cell proliferation. Impaired IgG responses in CD154TGCD22−/− mice were explained by a 16-fold expansion of functional, mature IL-10-competent regulatory spleen B cells (B10 cells: 26.7×106±6 in CD154TGCD22−/− mice; 1.7×106±0.4 in wild type mice, p<0.01), and an 11-fold expansion of B10 cells combined with their ex vivo-matured progenitors (B10+B10pro cells: 66×106±3 in CD154TGCD22−/− mice; 6.1×106±2 in wild type mice, p<0.01) that represented 39% of all spleen B cells.Conclusions/Significance
These results demonstrate for the first time that the IL-10-producing B10 B cell subset has the capacity to suppress IgG humoral immune responses against both foreign and self antigens. Thereby, therapeutic agents that drive regulatory B10 cell expansion in vivo may inhibit pathogenic IgG autoAb production in humans. 相似文献15.
16.
Anupam Mitra Smriti K Raychaudhuri Siba P Raychaudhuri 《Arthritis research & therapy》2012,14(2):R65-10
Introduction
Interleukin-22 (IL-22) is a cytokine of IL-10 family with significant proliferative effect on different cell lines. Immunopathological role of IL-22 has been studied in rheumatoid arthritis (RA) and psoriasis. Here we are reporting the functional role of IL-22 in the inflammatory and proliferative cascades of psoriatic arthritis (PsA).Method
From peripheral blood and synovial fluid (SF) of PsA (n = 15), RA (n = 15) and osteoarthritis (OA, n = 15) patients, mononuclear cells were obtained and magnetically sorted for CD3+ T cells. Fibroblast like synoviocytes (FLS) were isolated from the synovial tissue of PsA (n = 5), RA (n = 5) and OA (n = 5) patients. IL-22 levels in SF and serum were measured by enzyme linked immunosorbent assay (ELISA). Proliferative effect of human recombinant IL-22 (rIL-22) on FLS was assessed by MTT (3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide, a yellow tetrazole) and CFSE dilution (Carboxyfluorescein succinimidyl ester) assays. Expression of IL-22Rα1 in FLS was determined by western blot.Results
IL-22 levels were significantly elevated in SF of PsA patients (17.75 ± 3.46 pg/ml) compared to SF of OA (5.03 ± 0.39 pg/ml), p < 0.001. In MTT and CFSE dilution assays, rIL-22 (MTT, OD: 1.27 ± 0.06) induced significant proliferation of FLS derived from PsA patients compared to media (OD: 0.53 ± 0.02), p < 0.001. In addition, rIL-22 induced significantly more proliferation of FLS in presence of TNF-α. IL-22Rα1 was expressed in FLS of PsA, RA and OA patients. Anti IL-22R antibody significantly inhibited the proliferative effect of rIL-22. Further we demonstrated that activated synovial T cells of PsA and RA patients produced significantly more IL-22 than those of OA patients.Conclusion
SF of PsA patients have higher concentration of IL-22 and rIL-22 induced marked proliferation of PsA derived FLS. Moreover combination of rIL-22 and TNF-α showed significantly more proliferative effect on FLS. IL-22Rα1 was expressed in FLS. Successful inhibition of IL-22 induced FLS proliferation by anti IL-22R antibody suggests that blocking of IL-22/IL-22R interaction may be considered as a novel therapeutic target for PsA. 相似文献17.
Background
Synovial explants furnish an in-situ population of mesenchymal stem cells for the repair of articular cartilage. Although bone morphogenetic protein 2 (BMP-2) induces the chondrogenesis of bovine synovial explants, the cartilage formed is neither homogeneously distributed nor of an exclusively hyaline type. Furthermore, the downstream differentiation of chondrocytes proceeds to the stage of terminal hypertrophy, which is inextricably coupled with undesired matrix mineralization. With a view to optimizing BMP-2-induced chondrogenesis, the modulating influences of fibroblast growth factor 2 (FGF-2) and transforming growth factor beta 1 (TGF-ß1) were investigated.Methodology/Principal Findings
Explants of bovine calf metacarpal synovium were exposed to BMP-2 (200 ng/ml) for 4 (or 6) weeks. FGF-2 (10 ng/ml) or TGF-ß1 (10 ng/ml) was introduced at the onset of incubation and was present either during the first week of culturing alone or throughout its entire course. FGF-2 enhanced the BMP-2-induced increase in metachromatic staining for glycosaminoglycans (GAGs) only when it was present during the first week of culturing alone. TGF-ß1 enhanced not only the BMP-2-induced increase in metachromasia (to a greater degree than FGF-2), but also the biochemically-assayed accumulation of GAGs, when it was present throughout the entire culturing period; in addition, it arrested the downstream differentiation of cells at an early stage of hypertrophy. These findings were corroborated by an analysis of the gene- and protein-expression levels of key cartilaginous markers and by an estimation of individual cell volume.Conclusions/Significance
TGF-ß1 enhances the BMP-2-induced chondrogenesis of bovine synovial explants, improves the hyaline-like properties of the neocartilage, and arrests the downstream differentiation of cells at an early stage of hypertrophy. With the prospect of engineering a mature, truly articular type of cartilage in the context of clinical repair, our findings will be of importance in fine-tuning the stimulation protocol for the optimal chondrogenic differentiation of synovial explants. 相似文献18.
IL-6 induced STAT3 signalling is associated with the proliferation of human muscle satellite cells following acute muscle damage 总被引:1,自引:0,他引:1
Background
Although the satellite cell (SC) is a key regulator of muscle growth during development and muscle adaptation following exercise, the regulation of human muscle SC function remains largely unexplored. STAT3 signalling mediated via interleukin-6 (IL-6) has recently come to the forefront as a potential regulator of SC proliferation. The early response of the SC population in human muscle to muscle-lengthening contractions (MLC) as mediated by STAT3 has not been studied.Methodology/Principal Findings
Twelve male subjects (21±2 y; 83±12 kg) performed 300 maximal MLC of the quadriceps femoris at 180°•s−1 over a 55° range of motion with muscle samples (vastus lateralis) and blood samples (antecubital vein) taken prior to exercise (PRE), 1 hour (T1), 3 hours (T3) and 24 hours (T24) post-exercise. Cytoplasmic and nuclear fractions of muscle biopsies were purified and analyzed for total and phosphorylated STAT3 (p-STAT3) by western blot. p-STAT3 was detected in cytoplasmic fractions across the time course peaking at T24 (p<0.01 vs. PRE). Nuclear total and p-STAT3 were not detected at appreciable levels. However, immunohistochemical analysis revealed a progressive increase in the proportion of SCs expressing p-STAT3 with ∼60% of all SCs positive for p-STAT3 at T24 (p<0.001 vs. PRE). Additionally, cMyc, a STAT3 downstream gene, was significantly up-regulated in SCs at T24 versus PRE (p<0.05). Whole muscle mRNA analysis revealed induction of the STAT3 target genes IL-6, SOCS3, cMyc (peaking at T3, p<0.05), IL-6Rα and GP130 (peaking at T24, p<0.05). In addition, Myf5 mRNA was up-regulated at T24 (p<0.05) with no appreciable change in MRF4 mRNA.Conclusions/Significant Findings
We demonstrate that IL-6 induction of STAT3 signaling occurred exclusively in the nuclei of SCs in response to MLC. An increase in the number of cMyc+ SCs indicated that human SCs were induced to proliferate under the control of STAT3 signaling. 相似文献19.
Background
Levodopa treatment in Parkinson''s disease (PD) increases in serum homocysteine levels due to its metabolism via catechol O-methyltransferase. Endothelial progenitor cells (EPCs) have the capacity to differentiate into mature endothelial cells and are markers for endothelial functions and cardiovascular risks. Along with traditional vascular risk factors, hyperhomocysteinemia is known to decrease the level of EPCs. In the present study, we hypothesized that that levodopa-induced hyperhomocysteinemia leads to a change in EPC levels.Methodology/Principal Findings
We prospectively enrolled PD patients who had been prescribed either levodopa/carbidopa (PD-L group, n = 28) or levodopa/carbidopa/COMT inhibitor (PD-LC group, n = 25) for more than 1 year. The number of circulating EPCs was measured by flow cytometry using dual staining of anti-CD34 and anti-KDR antibodies. The EPCs were divided into tertiles based on their distributions and a logistic regression analysis was used to estimate independent predictors of the highest tertile of EPCs. The number of endothelial progenitor cells was significantly decreased in PD-L patients (118±99/mL) compared with either PD-LC patients (269±258/mL, p = 0.007) or controls (206±204/mL, p = 0.012). The level of homocysteine was significantly increased in PD-L patients (14.9±5.3 µmol/L) compared with either PD-LC patients (11.9±3.0 µmol/L, p = 0.028) or controls (11.1±2.5 µmol/L, p = 0.012). The level of homocysteine was negatively correlated with endothelial progenitor cell levels (r = −0.252, p = 0.028) and was an independent predictor of the highest tertile of endothelial progenitor cell levels (OR; 0.749 [95% CI: 0.584–0.961]).Conclusions/Significance
These data indicate that a higher consumption of EPC for restoration of endothelial damage may be associated with chronic levodopa treatment in PD patients. 相似文献20.
Jie Tang Chieh Allen Lee Yunpeng Du Yan Sun Eric Pearlman Nader Sheibani Timothy S. Kern 《PloS one》2013,8(7)