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1.
Methods and Results
The cardiac stem/progenitor cells from adult mice were seeded at low density in serum-free medium. The colonies thus obtained were expanded separately and assessed for expression of stem cell antigen-1 (Sca-1). Two colonies each with high Sca-1 (CSH1; 95.9%; CSH2; 90.6%) and low Sca-1 (CSL1; 37.1%; CSL2; 17.4%) expressing cells were selected for further studies. Sca-1+ cells (98.4%) isolated using Magnetic Cell Sorting System (MACS) from the hearts were used as a control. Although the selected populations were similar in surface marker expression (low in c-kit, CD45, CD34, CD31 and high in CD29), these cells exhibited diverse differentiation potential. Unlike CSH1, CSH2 expressed Nanog, TERT, Bcrp1, Nestin, Musashi1 and Isl-1, and also showed differentiation into osteogenic, chondrogenic, smooth muscle, endothelial and cardiac lineages. MACS sorted cells exhibited similar tendency albeit with relatively weaker differentiation potential. Transplantation of CSH2 cells into infarcted heart showed attenuated infarction size, significantly preserved left ventricular function and anterior wall thickness, and increased capillary density. We also observed direct differentiation of transplanted cells into endothelium and cardiomyocytes.Conclusions
The cardiac stem/progenitor cells isolated by a combined clonal selection and surface marker approach possessed multiple stem cell features important for cardiac regeneration. 相似文献2.
Yang J Ii M Kamei N Alev C Kwon SM Kawamoto A Akimaru H Masuda H Sawa Y Asahara T 《PloS one》2011,6(5):e20219
Background
Endothelial progenitor cells (EPCs) were shown to have angiogenic potential contributing to neovascularization. However, a clear definition of mouse EPCs by cell surface markers still remains elusive. We hypothesized that CD34 could be used for identification and isolation of functional EPCs from mouse bone marrow.Methodology/Principal Findings
CD34+ cells, c-Kit+/Sca-1+/Lin− (KSL) cells, c-Kit+/Lin− (KL) cells and Sca-1+/Lin− (SL) cells were isolated from mouse bone marrow mononuclear cells (BMMNCs) using fluorescent activated cell sorting. EPC colony forming capacity and differentiation capacity into endothelial lineage were examined in the cells. Although CD34+ cells showed the lowest EPC colony forming activity, CD34+ cells exhibited under endothelial culture conditions a more adherent phenotype compared with the others, demonstrating the highest mRNA expression levels of endothelial markers vWF, VE-cadherin, and Flk-1. Furthermore, a dramatic increase in immediate recruitment of cells to the myocardium following myocardial infarction and systemic cell injection was observed for CD34+ cells comparing with others, which could be explained by the highest mRNA expression levels of key homing-related molecules Integrin β2 and CXCR4 in CD34+ cells. Cell retention and incorporation into the vasculature of the ischemic myocardium was also markedly increased in the CD34+ cell-injected group, giving a possible explanation for significant reduction in fibrosis area, significant increase in neovascularization and the best cardiac functional recovery in this group in comparison with the others.Conclusion
These findings suggest that mouse CD34+ cells may represent a functional EPC population in bone marrow, which could benefit the investigation of therapeutic EPC biology. 相似文献3.
Settles M Etzrodt M Kosanke K Schiemann M Zimmermann A Meier R Braren R Huber A Rummeny EJ Weissleder R Swirski FK Wildgruber M 《PloS one》2011,6(10):e25197
Objective
To explore the capacity of human CD14+CD16++ and CD14++CD16- monocytes to phagocyte iron-oxide nanoparticles in vitro.Methods
Human monocytes were labeled with four different magnetic nanoparticle preparations (Ferumoxides, SHU 555C, CLIO-680, MION-48) exhibiting distinct properties and cellular uptake was quantitatively assessed by flow cytometry, fluorescence microscopy, atomic absorption spectrometry and Magnetic Resonance Imaging (MRI). Additionally we determined whether cellular uptake of the nanoparticles resulted in phenotypic changes of cell surface markers.Results
Cellular uptake differed between the four nanoparticle preparations. However for each nanoparticle tested, CD14++CD16- monocytes displayed a significantly higher uptake compared to CD14+CD16++ monocytes, this resulted in significantly lower T1 and T2 relaxation times of these cells. The uptake of iron-oxide nanoparticles further resulted in a remarkable shift of expression of cell surface proteins indicating that the labeling procedure affects the phenotype of CD14+CD16++ and CD14++CD16- monocytes differently.Conclusion
Human monocyte subsets internalize different magnetic nanoparticle preparations differently, resulting in variable loading capacities, imaging phenotypes and likely biological properties. 相似文献4.
Background
The ectoenzymes CD39 and CD73 are expressed by a broad range of immune cells and promote the extracellular degradation of nucleotides to anti-inflammatory adenosine. This study explored the abundance of CD73 and CD39 on circulating and resident cardiac leukocytes and coronary endothelial cells under control conditions and in response to inflammation following myocardial ischemia and reperfusion (I/R).Methods and Results
A method was elaborated to permit FACS analysis of non-myocardial cells (resident leukocytes, coronary endothelium and CD31− CD45− cells) of the unstressed heart. Under control conditions the murine heart contained 2.3×103 resident leukocytes/mg tissue, the most prominent fraction being antigen-presenting mononuclear cells (CD11b+ CD11c+ F4/80+ MHCII+) followed by B-cells, monocytes and T-cells. CD73 was highly expressed on circulating and resident cardiac lymphoid cells with little expression on myeloid cells, while the opposite was true for CD39. Cardiomyocytes and erythrocytes do not measurably express CD39/CD73 and CD39 dominates on coronary endothelium. Three days after I/R, CD73 was significantly upregulated on invading granulocytes (2.8-fold) and T-cells (1.5-fold). Compared with coronary endothelial cells, CD73 associated with leukocytes comprised 2/3 of the total cardiac CD73.Conclusion
Our study suggests that extracellular ATP formed during I/R is preferentially degraded by CD39 present on myeloid cells, while the formation of immunosuppressive adenosine is mainly catalysed by CD73 present on granulocytes and lymphoid cells. Upregulated CD73 on granulocytes and T-cells infiltrating the injured heart is consistent with the existence of an autocrine adenosinergic loop which may promote the healing process. 相似文献5.
Jana S Campbell H Woodliff J Waukau J Jailwala P Ghorai J Ghosh S Glisic S 《PloS one》2010,5(12):e15154
Background
In type 1 diabetes (T1D), a prototypic autoimmune disease, effector T cells destroy beta cells. Normally, CD4+CD25+high, or natural regulatory T cells (Tregs), counter this assault. In autoimmunity, the failure to suppress CD4+CD25low T cells is important for disease development. However, both Treg dysfunction and hyperactive responder T-cell proliferation contribute to disease.Methods/Principal Findings
We investigated human CD4+CD25low T cells and compared them to CD4+CD25- T cells in otherwise equivalent in vitro proliferative conditions. We then asked whether these differences in suppression are exacerbated in T1D. In both single and co-culture with Tregs, the CD4+CD25low T cells divided more rapidly than CD4+CD25- T cells, which manifests as increased proliferation/reduced suppression. Time-course experiments showed that this difference could be explained by higher IL-2 production from CD4+CD25low compared to CD4+CD25- T cells. There was also a significant increase in CD4+CD25low T-cell proliferation compared to CD4+CD25- T cells during suppression assays from RO T1D and at-risk subjects (n = 28, p = 0.015 and p = 0.024 respectively).Conclusions/Significance
The in vitro dual suppression assays proposed here could highlight the impaired sensitivity of certain responder T cells to the suppressive effect of Tregs in human autoimmune diseases. 相似文献6.
Mueller H Faé KC Magdorf K Ganoza CA Wahn U Guhlich U Feiterna-Sperling C Kaufmann SH 《PloS one》2011,6(12):e29367
Background
Granulysin produced by cytolytic T cells directly contributes to immune defense against tuberculosis (TB). We investigated granulysin as a candidate immune marker for childhood and adolescent TB.Methods
Peripheral blood mononuclear cells (PBMC) from children and adolescents (1–17 years) with active TB, latent TB infection (LTBI), nontuberculous mycobacteria (NTM) infection and from uninfected controls were isolated and restimulated in a 7-day restimulation assay. Intracellular staining was then performed to analyze antigen-specific induction of activation markers and cytotoxic proteins, notably, granulysin in CD4+ CD45RO+ memory T cells.Results
CD4+ CD45RO+ T cells co-expressing granulysin with specificity for Mycobacterium tuberculosis (Mtb) were present in high frequency in TB-experienced children and adolescents. Proliferating memory T cells (CFSElowCD4+CD45RO+) were identified as main source of granulysin and these cells expressed both central and effector memory phenotype. PBMC from study participants after TB drug therapy revealed that granulysin-expressing CD4+ T cells are long-lived, and express several activation and cytotoxicity markers with a proportion of cells being interferon-gamma-positive. In addition, granulysin-expressing T cell lines showed cytolytic activity against Mtb-infected target cells.Conclusions
Our data suggest granulysin expression by CD4+ memory T cells as candidate immune marker for TB infection, notably, in childhood and adolescence. 相似文献7.
Lang KS Hegazy AN Lang PA Eschli B Löhning M Hengartner H Zinkernagel RM Recher M 《PloS one》2007,2(11):e1162
Background
Cooperation of CD4+ T helper cells with specific B cells is crucial for protective vaccination against pathogens by inducing long-lived neutralizing antibody responses. During infection with persistence-prone viruses, prolonged virus replication correlates with low neutralizing antibody responses. We recently described that a viral mutant of lymphocytic choriomeningitis virus (LCMV), which lacks a T helper epitope, counterintuitively induced an enhanced protective antibody response. Likewise, partial depletion of the CD4+ T cell compartment by using anti-CD4 antibodies enhanced protective antibodies.Principal Findings
Here we have developed a protocol to selectively reduce the CD4+ T cell response against viral CD4+ T cell epitopes. We demonstrate that in vivo treatment with LCMV-derived MHC-II peptides induced non-responsiveness of specific CD4+ T cells without affecting CD4+ T cell reactivity towards other antigens. This was associated with accelerated virus-specific neutralizing IgG-antibody responses. In contrast to a complete absence of CD4+ T cell help, tolerisation did not impair CD8+ T cell responses.Conclusions
This result reveals a novel “negative vaccination” strategy where specific CD4+ T cell unresponsiveness may be used to enhance the delayed protective antibody responses in chronic virus infections. 相似文献8.
Tang TT Zhu ZF Wang J Zhang WC Tu X Xiao H Du XL Xia JH Dong NG Su W Xia N Yan XX Nie SF Liu J Zhou SF Yao R Xie JJ Jevallee H Wang X Liao MY Shi GP Fu M Liao YH Cheng X 《PloS one》2011,6(9):e24272
Objective
Animal studies suggest that regulatory T (Treg) cells play a beneficial role in ventricular remodeling and our previous data have demonstrated defects of Treg cells in patients with chronic heart failure (CHF). However, the mechanisms behind Treg-cell defects remained unknown. We here sought to elucidate the mechanism of Treg-cell defects in CHF patients.Methods and Results
We performed flow cytometry analysis and demonstrated reduced numbers of peripheral blood CD4+CD25+FOXP3+CD45RO−CD45RA+ naïve Treg (nTreg) cells and CD4+CD25+FOXP3+CD45RO+CD45RA− memory Treg (mTreg) cells in CHF patients as compared with non-CHF controls. Moreover, the nTreg/mTreg ratio (p<0.01), CD4+CD25+FOXP3+CD45RO− CD45RA+CD31+ recent thymic emigrant Treg cell (RTE-Treg) frequency (p<0.01), and T-cell receptor excision circle levels in Treg cells (p<0.01) were lower in CHF patients than in non-CHF controls. Combined annexin-V and 7-AAD staining showed that peripheral Treg cells from CHF patients exhibited increased spontaneous apoptosis and were more prone to interleukin (IL)-2 deprivation- and CD95 ligand-mediated apoptosis than those from non-CHF individuals. Furthermore, analyses by both flow cytometry and real-time polymerase chain reaction showed that Treg-cell frequency in the mediastinal lymph nodes or Foxp3 expression in hearts of CHF patients was no higher than that of the non-CHF controls.Conclusion
Our data suggested that the Treg-cell defects of CHF patients were likely caused by decreased thymic output of nascent Treg cells and increased susceptibility to apoptosis in the periphery. 相似文献9.
Burridge PW Thompson S Millrod MA Weinberg S Yuan X Peters A Mahairaki V Koliatsos VE Tung L Zambidis ET 《PloS one》2011,6(4):e18293
Background
The production of cardiomyocytes from human induced pluripotent stem cells (hiPSC) holds great promise for patient-specific cardiotoxicity drug testing, disease modeling, and cardiac regeneration. However, existing protocols for the differentiation of hiPSC to the cardiac lineage are inefficient and highly variable. We describe a highly efficient system for differentiation of human embryonic stem cells (hESC) and hiPSC to the cardiac lineage. This system eliminated the variability in cardiac differentiation capacity of a variety of human pluripotent stem cells (hPSC), including hiPSC generated from CD34+ cord blood using non-viral, non-integrating methods.Methodology/Principal Findings
We systematically and rigorously optimized >45 experimental variables to develop a universal cardiac differentiation system that produced contracting human embryoid bodies (hEB) with an improved efficiency of 94.7±2.4% in an accelerated nine days from four hESC and seven hiPSC lines tested, including hiPSC derived from neonatal CD34+ cord blood and adult fibroblasts using non-integrating episomal plasmids. This cost-effective differentiation method employed forced aggregation hEB formation in a chemically defined medium, along with staged exposure to physiological (5%) oxygen, and optimized concentrations of mesodermal morphogens BMP4 and FGF2, polyvinyl alcohol, serum, and insulin. The contracting hEB derived using these methods were composed of high percentages (64–89%) of cardiac troponin I+ cells that displayed ultrastructural properties of functional cardiomyocytes and uniform electrophysiological profiles responsive to cardioactive drugs.Conclusion/Significance
This efficient and cost-effective universal system for cardiac differentiation of hiPSC allows a potentially unlimited production of functional cardiomyocytes suitable for application to hPSC-based drug development, cardiac disease modeling, and the future generation of clinically-safe nonviral human cardiac cells for regenerative medicine. 相似文献10.
Jacqueline Araújo Fiuza Ricardo Toshio Fujiwara Juliana Assis Silva Gomes Manoel Otávio das Costa Rocha Ana Thereza Chaves Fernanda Fortes de Araújo Rafaelle Christine Gomes Fares Andrea Teixeira-Carvalho Olindo de Assis Martins-Filho Guilherme Grossi Lopes Can?ado Rodrigo Correa-Oliveira 《PLoS neglected tropical diseases》2009,3(9)
Background
Chronic Chagas disease presents several different clinical manifestations ranging from asymptomatic to severe cardiac and/or digestive clinical forms. Several studies have demonstrated that immunoregulatory mechanisms are important processes for the control of the intense immune activity observed in the chronic phase. T cells play a critical role in parasite specific and non-specific immune response elicited by the host against Trypanosoma cruzi. Specifically, memory T cells, which are basically classified as central and effector memory cells, might have a distinct migratory activity, role and function during the human Chagas disease.Methodology/Principal Findings
Based on the hypothesis that the disease severity in humans is correlated to the quality of immune responses against T. cruzi, we evaluated the memory profile of peripheral CD4+ and CD8+ T lymphocytes as well as its cytokine secretion before and after in vitro antigenic stimulation. We evaluated cellular response from non-infected individuals (NI), patients with indeterminate (IND) or cardiac (CARD) clinical forms of Chagas disease. The expression of CD45RA, CD45RO and CCR7 surface molecules was determined on CD4+ and CD8+ T lymphocytes; the pattern of intracellular cytokines (IFN-γ, IL-10) synthesized by naive and memory cells was determined by flow cytometry. Our results revealed that IND and CARD patients have relatively lower percentages of naive (CD45RAhigh) CD4+ and CD8+ T cells. However, statistical analysis of ex-vivo profiles of CD4+ T cells showed that IND have lower percentage of CD45RAhigh in relation to non-infected individuals, but not in relation to CARD. Elevated percentages of memory (CD45ROhigh) CD4+ T cells were also demonstrated in infected individuals, although statistically significant differences were only observed between IND and NI groups. Furthermore, when we analyzed the profile of secreted cytokines, we observed that CARD patients presented a significantly higher percentage of CD8+CD45RAhigh IFN-γ-producing cells in control cultures and after antigen pulsing with soluble epimastigote antigens.Conclusions
Based on a correlation between the frequency of IFN-γ producing CD8+ T cells in the T cell memory compartment and the chronic chagasic myocarditis, we propose that memory T cells can be involved in the induction of the development of the severe clinical forms of the Chagas disease by mechanisms modulated by IFN-γ. Furthermore, we showed that individuals from IND group presented more TCM CD4+ T cells, which may induce a regulatory mechanism to protect the host against the exacerbated inflammatory response elicited by the infection. 相似文献11.
Limana F Esposito G D'Arcangelo D Di Carlo A Romani S Melillo G Mangoni A Bertolami C Pompilio G Germani A Capogrossi MC 《PloS one》2011,6(6):e19845
Aims
HMGB1 injection into the mouse heart, acutely after myocardial infarction (MI), improves left ventricular (LV) function and prevents remodeling. Here, we examined the effect of HMGB1 in chronically failing hearts.Methods and Results
Adult C57 BL16 female mice underwent coronary artery ligation; three weeks later 200 ng HMGB1 or denatured HMGB1 (control) were injected in the peri-infarcted region of mouse failing hearts. Four weeks after treatment, both echocardiography and hemodynamics demonstrated a significant improvement in LV function in HMGB1-treated mice. Further, HMGB1-treated mice exhibited a ∼23% reduction in LV volume, a ∼48% increase in infarcted wall thickness and a ∼14% reduction in collagen deposition. HMGB1 induced cardiac regeneration and, within the infarcted region, it was found a ∼2-fold increase in c-kit+ cell number, a ∼13-fold increase in newly formed myocytes and a ∼2-fold increase in arteriole length density. HMGB1 also enhanced MMP2 and MMP9 activity and decreased TIMP-3 levels. Importantly, miR-206 expression 3 days after HMGB1 treatment was 4-5-fold higher than in control hearts and 20–25 fold higher that in sham operated hearts. HMGB1 ability to increase miR-206 was confirmed in vitro, in cardiac fibroblasts. TIMP3 was identified as a potential miR-206 target by TargetScan prediction analysis; further, in cultured cardiac fibroblasts, miR-206 gain- and loss-of-function studies and luciferase reporter assays showed that TIMP3 is a direct target of miR-206.Conclusions
HMGB1 injected into chronically failing hearts enhanced LV function and attenuated LV remodelling; these effects were associated with cardiac regeneration, increased collagenolytic activity, miR-206 overexpression and miR-206 -mediated inhibition of TIMP-3. 相似文献12.
Sharp ER Willberg CB Kuebler PJ Abadi J Fennelly GJ Dobroszycki J Wiznia AA Rosenberg MG Nixon DF 《PloS one》2012,7(1):e29154
Background
In the USA, most HIV-1 infected children are on antiretroviral drug regimens, with many individuals surviving through adolescence and into adulthood. The course of HIV-1 infection in these children is variable, and understudied.Methodology/Principal Findings
We determined whether qualitative differences in immune cell subsets could explain a slower disease course in long term survivors with no evidence of immune suppression (LTS-NS; CD4%≥25%) compared to those with severe immune suppression (LTS-SS; CD4%≤15%). Subjects in the LTS-NS group had significantly higher frequencies of naïve (CCR7+CD45RA+) and central memory (CCR7+CD45RA−) CD4+ T cells compared to LTS-SS subjects (p = 0.0005 and <0.0001, respectively). Subjects in the rapid progressing group had significantly higher levels of CD4+ TEMRA (CCR7−CD45RA+) cells compared to slow progressing subjects (p<0.0001).Conclusions/Significance
Rapid disease progression in vertical infection is associated with significantly higher levels of CD4+ TEMRA (CCR7−CD45RA+) cells. 相似文献13.
Nemeth J Winkler HM Zwick RH Müller C Rumetshofer R Boeck L Burghuber OC Winkler S 《PloS one》2012,7(4):e35290
Background
A test for diagnosis of active Tuberculosis (TB) from peripheral blood could tremendously improve clinical management of patients.Methods
Of 178 prospectively enrolled patients with possible TB, 60 patients were diagnosed with pulmonary and 27 patients with extrapulmonary TB. The frequencies of Mycobacterium tuberculosis (MTB) specific CD4+ T cells and CD8+ T cells producing cytokines were assessed using overnight stimulation with purified protein derivate (PPD) or early secretory antigenic target (ESAT)-6, respectively.Results
Among patients with active TB, an increased type 1 cytokine profile consisting of mainly CD4+ T cell derived interferon (IFN)-γ was detectable. Despite contributing to the cytokine profile as a whole, the independent diagnostic performance of one cytokine producing T cells as well as polyfunctional T cells was poor. IFN-γ/Interleukin(IL)-2 cytokine ratios discriminated best between active TB and other diseases.Conclusion
T cells producing one cytokine and polyfunctional T cells have a limited role in diagnosis of active TB. The significant shift from a “memory type” to an “effector type” cytokine profile may be useful for further development of a rapid immune-diagnostic tool for active TB. 相似文献14.
Schmidt-Lucke C Fichtlscherer S Aicher A Tschöpe C Schultheiss HP Zeiher AM Dimmeler S 《PloS one》2010,5(11):e13790
Aims
Circulating endothelial progenitor cells (EPC), involved in endothelial regeneration, neovascularisation, and determination of prognosis in cardiovascular disease can be characterised with functional assays or using immunofluorescence and flow cytometry. Combinations of markers, including CD34+KDR+ or CD133+KDR+, are used. This approach, however may not consider all characteristics of EPC. The lack of a standardised protocol with regards to reagents and gating strategies may account for the widespread inter-laboratory variations in quantification of EPC. We, therefore developed a novel protocol adapted from the standardised so-called ISHAGE protocol for enumeration of haematopoietic stem cells to enable comparison of clinical and laboratory data.Methods and Results
In 25 control subjects, 65 patients with coronary artery disease (CAD; 40 stable CAD, 25 acute coronary syndrome/acute myocardial infarction (ACS)), EPC were quantified using the following approach: Whole blood was incubated with CD45, KDR, and CD34. The ISHAGE sequential strategy was used, and finally, CD45dimCD34+ cells were quantified for KDR. A minimum of 100 CD34+ events were collected. For comparison, CD45+CD34+ and CD45−CD34+ were analysed simultaneously. The number of CD45dimCD34+KDR+ cells only were significantly higher in healthy controls compared to patients with CAD or ACS (p = 0.005 each, p<0.001 for trend). An inverse correlation of CD45dimCD34+KDR+ with disease activity (r = −0.475, p<0.001) was confirmed. Only CD45dimCD34+KDR+ correlated inversely with the number of diseased coronaries (r = −0.344; p<0.005). In a second study, a 4-week de-novo treatment of atorvastatin in stable CAD evoked an increase only of CD45dimCD34+KDR+ EPC (p<0.05). CD45+CD34+KDR+ and CD45−CD34+KDR+ were indifferent between the three groups.Conclusion
Our newly established protocol adopted from the standardised ISHAGE protocol achieved higher accuracy in EPC enumeration confirming previous findings with respect to the correlation of EPC with disease activity and the increase of EPC during statin therapy. The data of this study show the CD45dim fraction to harbour EPC. 相似文献15.
Carr CA Stuckey DJ Tan JJ Tan SC Gomes RS Camelliti P Messina E Giacomello A Ellison GM Clarke K 《PloS one》2011,6(10):e25669
Aims
Endogenous cardiac progenitor cells, expanded from explants via cardiosphere formation, present a promising cell source to prevent heart failure following myocardial infarction. Here we used cine-magnetic resonance imaging (MRI) to track administered cardiosphere-derived cells (CDCs) and to measure changes in cardiac function over four months in the infarcted rat heart.Methods and Results
CDCs, cultured from neonatal rat heart, comprised a heterogeneous population including cells expressing the mesenchymal markers CD90 and CD105, the stem cell marker c-kit and the pluripotency markers Sox2, Oct3/4 and Klf-4. CDCs (2×106) expressing green fluorescent protein (GFP+) were labelled with fluorescent micron-sized particles of iron oxide (MPIO). Labelled cells were administered to the infarcted rat hearts (n = 7) by intramyocardial injection immediately following reperfusion, then by systemic infusion (4×106) 2 days later. A control group (n = 7) was administered cell medium. MR hypointensities caused by the MPIOs were detected at all times and GFP+ cells containing MPIO particles were identified in tissue slices at 16 weeks. At two days after infarction, cardiac function was similar between groups. By 6 weeks, ejection fractions in control hearts had significantly decreased (47±2%), but this was not evident in CDC-treated hearts (56±3%). The significantly higher ejection fractions in the CDC-treated group were maintained for a further 10 weeks. In addition, CDC-treated rat hearts had significantly increased capillary density in the peri-infarct region and lower infarct sizes. MPIO-labelled cells also expressed cardiac troponin I, von Willebrand factor and smooth muscle actin, suggesting their differentiation along the cardiomyocyte lineage and the formation of new blood vessels.Conclusions
CDCs were retained in the infarcted rat heart for 16 weeks and improved cardiac function. 相似文献16.
Background
Although diseases associated with microvascular endothelial dysfunction are among the most prevalent illnesses to date, currently no method exists to isolate pure endothelial cells (EC) from skeletal muscle for in vivo or in vitro study.Methodology
By utilizing multicolor fluorescent-activated cell sorting (FACS), we have isolated a distinct population of Sca-1+, CD31+, CD34dim and CD45− cells from skeletal muscles of C57BL6 mice. Characterization of this population revealed these cells are functional EC that can be expanded several times in culture without losing their phenotype or capabilities to uptake acetylated low-density lipoprotein (ac-LDL), produce nitric oxide (NO) and form vascular tubes. When transplanted subcutaneously or intramuscularly into the tibialis anterior muscle, EC formed microvessels and integrated with existing vasculature.Conclusion
This method, which is highly reproducible, can be used to study the biology and role of EC in diseases such as peripheral vascular disease. In addition this method allows us to isolate large quantities of skeletal muscle derived EC with potential for therapeutic angiogenic applications. 相似文献17.
Giuliani M Giron-Michel J Negrini S Vacca P Durali D Caignard A Le Bousse-Kerdiles C Chouaib S Devocelle A Bahri R Durrbach A Taoufik Y Ferrini S Croce M Mingari MC Moretta L Azzarone B 《PloS one》2008,3(5):e2241
Background
NK cells have been long time considered as cytotoxic lymphocytes competent in killing virus-infected cells and tumors. However, NK cells may also play essential immuno-regulatory functions. In this context, the real existence of a defined NK subset with negative regulatory properties has been hypothesized but never clearly demonstrated.Methodology/Principal Findings
Herein, we show the in vitro generation from human peripheral blood haematopoietic progenitors (PB-HP), of a novel subset of non-cytolytic NK cells displaying a mature phenotype and remarkable immuno-regulatory functions (NK-ireg). The main functional hallmark of these NK-ireg cells is represented by the surface expression/release of HLA-G, a major immunosuppressive molecule. In addition, NK-ireg cells secrete two powerful immuno-regulatory factors: IL-10 and IL-21. Through these factors, NK-ireg cells act as effectors of the down-regulation of the immune response: reconverting mature myeloid DC (mDC) into immature/tolerogenic DC, blocking cytolytic functions on conventional NK cells and inducing HLA-G membrane expression on PB-derived monocytes. The generation of “NK-ireg” cells is obtained, by default, in culture conditions favouring cell-to-cell contacts, and it is strictly dependent on reciprocal trans-presentation of membrane-bound IL-15 forms constitutively and selectively expressed by human CD34+ PB-HP. Finally, a small subset of NKp46+ HLA-G+ IL-10+ is detected within freshly isolated decidual NK cells, suggesting that these cells could represent an in vivo counterpart of the NK-ireg cells.Conclusions/Significance
In conclusion, NK-ireg cells represent a novel truly differentiated non-cytolytic NK subset with a self-sustainable phenotype (CD56+ CD16+ NKp30+ NKp44+ NKp46+ CD94+ CD69+ CCR7+) generated from specific pSTAT6+ GATA3+ precursors. NK-ireg cells could be employed to develop new immuno-suppressive strategies in autoimmune diseases, transplant rejection or graft versus host diseases. In addition, NK-ireg cells can be easily derived from peripheral blood of the patients and could constitute an autologous biotherapic tool to be used combined or in alternative to other immuno-regulatory cells. 相似文献18.
Munir S Larsen SK Iversen TZ Donia M Klausen TW Svane IM Straten PT Andersen MH 《PloS one》2012,7(4):e34568
Background
The enzyme indoleamine 2,3-dioxygenase (IDO) contributes to immune tolerance in a variety of settings. In cancer IDO is expressed within the tumor itself as well as in antigen-presenting cells in tumor-draining lymph nodes, where it endorses the establishment of peripheral immune tolerance to tumor antigens. Recently, we described cytotoxic CD8+ T-cell reactivity towards IDO-derived peptides.Methods and Findings
In the present study, we show that CD4+ helper T cells additionally spontaneously recognize IDO. Hence, we scrutinized the vicinity of the previously described HLA-A*0201-restricted IDO-epitope for CD4+ T-cell epitopes. We demonstrated the presence of naturally occurring IDO-specific CD4+ T cells in cancer patients and to a lesser extent in healthy donors by cytokine release ELISPOT. IDO-reactive CD4+ T cells released IFN-γ, TNF-α, as well as IL-17. We confirm HLA class II-restriction by the addition of HLA class II specific blocking antibodies. In addition, we detected a trend between class I- and class II-restricted IDO responses and detected an association between IDO-specific CD4+ T cells and CD8+ CMV-responses. Finally, we could detect IL-10 releasing IDO-reactive CD4+ T cells.Conclusion
IDO is spontaneously recognized by HLA class II-restricted, CD4+ T cells in cancer patients and in healthy individuals. IDO-specific T cells may participate in immune-regulatory networks where the activation of pro-inflammatory IDO-specific CD4+ responses may well overcome or delay the immune suppressive actions of the IDO-protein, which are otherwise a consequence of the early expression of IDO in maturing antigen presenting cells. In contrast, IDO-specific regulatory T cells may enhance IDO-mediated immune suppression. 相似文献19.
20.
Sasson SC Zaunders JJ Seddiki N Bailey M McBride K Koelsch KK Merlin KM Smith DE Cooper DA Kelleher AD 《PloS one》2012,7(2):e31148