Jichao Ye

Reduced immunomodulation potential of bone marrow-derived mesenchymal stem cells induced CCR4+CCR6+ Th/Treg cell subset imbalance in ankylosing spondylitis.

IntroductionAnkylosing spondylitis (AS) is a chronic autoimmune disease, and the precise pathogenesis is largely unknown at present. Bone marrow-derived mesenchymal stem cells (BMSCs) with immunosuppressive and anti-inflammatory potential and Th17/Treg cells with a reciprocal relationship regulated by BMSCs have been reported to be involved in some autoimmune disorders. Here we studied the biological and immunological characteristics of BMSCs, the frequency and phenotype of CCR4+CCR6+ Th/Treg cells and their interaction in vitro in AS.MethodsThe biological and immunomodulation characteristics of BMSCs were examined by induced multiple-differentiation and two-way mixed peripheral blood mononuclear cell (PBMC) reactions or after stimulation with phytohemagglutinin, respectively. The interactions of BMSCs and PBMCs were detected with a direct-contact co-culturing system. CCR4+CCR6+ Th/Treg cells and surface markers of BMSCs were assayed using flow cytometry.ResultsThe AS-BMSCs at active stage showed normal proliferation, cell viability, surface markers and multiple differentiation characteristics, but significantly reduced immunomodulation potential (decreased 68 ± 14%); the frequencies of Treg and Fox-P3+ cells in AS-PBMCs decreased, while CCR4+CCR6+ Th cells increased, compared with healthy donors. Moreover, the AS-BMSCs induced imbalance in the ratio of CCR4+CCR6+ Th/Treg cells by reducing Treg/PBMCs and increasing CCR4+CCR6+ Th/PBMCs, and also reduced Fox-P3+ cells when co-cultured with PBMCs. Correlation analysis showed that the immunomodulation potential of BMSCs has significant negative correlations with the ratio of CCR4+CCR6+ Th to Treg cells in peripheral blood.ConclusionsThe immunomodulation potential of BMSCs is reduced and the ratio of CCR4+CCR6+ Th/Treg cells is imbalanced in AS. The BMSCs with reduced immunomodulation potential may play a novel role in AS pathogenesis by inducing CCR4+CCR6+ Th/Treg cell imbalance.

Effects and Safety of Allogenic Mesenchymal Stem Cell Intravenous Infusion in Active Ankylosing Spondylitis Patients who Failed NSAIDs: A 20-Week Clinical Trial

Our objective was to evaluate the feasibility, safety, and efficacy of intravenous (IV) infusion of allogenic mesenchymal stem cells (MSCs) in ankylosing spondylitis (AS) patients who are refractory to or cannot tolerate the side effects of nonsteroidal anti-inflammatory drugs (NSAIDs). AS patients enrolled in this study received four IV infusions of MSCs on days 0, 7, 14, and 21. The percentage of ASAS20 responders (the primary endpoint) at the fourth week and the mean ASAS20 response duration (the secondary endpoint) were used to assess treatment response to MSC infusion and duration of the therapeutic effects. Ankylosing Spondylitis Disease Activity Score Containing C-reactive Protein (ASDAS-CRP) and other preestablished evaluation indices were also adopted to evaluate the clinical effects. Magnetic resonance imaging (MRI) was performed to detect changes of bone marrow edema in the spine. The safety of this treatment was also evaluated. Thirty-one patients were included, and the percentage of ASAS20 responders reached 77.4% at the fourth week, and the mean ASAS20 response duration was 7.1 weeks. The mean ASDAS-CRP score decreased from 3.6 ± 0.6 to 2.4 ± 0.5 at the fourth week and then increased to 3.2 ± 0.8 at the 20th week. The average total inflammation extent (TIE) detected by MRI decreased from 533,482.5 at baseline to 480,692.3 at the fourth week (p > 0.05) and 400,547.2 at the 20th week (p < 0.05). No adverse effects were noted. IV infusion of MSCs is a feasible, safe, and promising treatment for patients with AS.

Epidemiology of spinal cord injuries and risk factors for complete injuries in Guangdong, China: A retrospective study

Background Spinal cord injuries are highly disabling and deadly injuries. Currently, few studies focus on non-traumatic spinal cord injuries, and there is little information regarding the risk factors for complete injuries. This study aims to describe the demographics and the injury characteristics for both traumatic and non-traumatic spinal cord injuries and to explore the risk factors for complete spinal cord injuries. Methods A retrospective study was performed by reviewing the medical records of 3,832 patients with spinal cord injuries who were first admitted to the sampled hospitals in Guangdong, China. The demographics and injury characteristics of the patients were described and compared between the different groups using the chi-square test. Logistic regression was conducted to analyze the risk factors for complete spinal cord injuries. Results The proportion of patients increased from 7.0% to 14.0% from 2003 to 2011. The male-to-female ratio was 3.0∶1. The major cause of spinal cord injuries was traffic accidents (21.7%). Many of the injured were workers (36.2%), peasants (22.8%), and unemployed people (13.9%); these occupations accounted for 72.9% of the total sample. A multivariate logistic regression model revealed that the OR (95% CI) for male gender compared to female gender was 1.25 (1.07–1.89), the OR (95%CI) for having a spinal fracture was 1.56 (1.35–2.60), the OR (95%CI) for having a thoracic injury was 1.23 (1.10–2.00), and the OR (95%CI) for having complications was 2.47 (1.96–3.13). Conclusion The proportion of males was higher than the proportion of females. Workers, peasants and the unemployed comprised the high-risk occupational categories. Male gender, having a spinal fracture, having a thoracic injury, and having complications were the major risk factors for a complete injury. We recommend that preventive measures should focus on high-risk populations, such as young males.

Sensitivity and specificity of in vivo diffusion-weighted MRI in acute spinal cord injury

The aim of this study was to test the sensitivity and specificity of diffusion-weighted MRI for the detection of acute spinal cord injury. Forty female New Zealand white rabbits were randomly divided into four groups: the mild, moderate and severe injury groups, and the control (sham operation) group. Contusion of the spinal cord was induced using a weight-drop impactor. All animals were imaged using T1-weighted, T2-weighted, and diffusion-weighted imaging (DWI) sequences at 30 minutes, 6 hours, and 24 hours after injury. One animal from each group was killed at each time point for histologic examination of the spinal cord. DWI had a sensitivity of 100% at all time points, whereas T2-weighted MRI had a sensitivity of 43.33% at 30 minutes after injury, 81.48% at 6 hours after injury, and 95.83% at 24 hours after injury. Conversely, the specificity of DWI was lower than that of T2-weighted MRI at all time points. One animal in the control group had a non-specific high signal on DWI. Significant systematic differences were seen between DWI and T2-weighted MRI at both 30 minutes and 6 hours after injury. The apparent diffusion coefficient values of the lesion were lower than those of adjacent unaffected regions in the mild and moderate injury groups, but higher than adjacent unaffected regions in the severe injury group. The histological findings were reliably correlated with the magnetic resonance findings. We found that DWI has a higher sensitivity, but a lower specificity, than conventional MRI for the detection of early pathological changes after contusive injury.

The vascular supply to the spinal cord and its relationship to anterior spine surgical approaches

BACKGROUND CONTEXT The understanding of vascular supply to the spinal cord is important given that the evolution of surgical approaches to the spine may bring along the potential for more frequent complications, especially a rare but devastating complication: that of spinal cord ischemia or infarction. To maximally avoid this complication, the relationship between the spinal cord vascularity and the anterior spine surgical approach needs further study. PURPOSE To provide a theoretical basis that will allow the spinal surgeon to take appropriate steps to avoid spinal cord ischemia during anterior spinal surgery through anatomic means. STUDY DESIGN Spinal cord vascular casting assessment with cadaveric specimen. METHODS Twenty adult cadaveric specimens (11 men and 9 women) were obtained for the latex perfusion and vessel dissection. In addition, nine patients (seven men and two women) underwent superselective angiography of the spinal cord. The segmental arterial anastomosis and radiculomedullary vessels in the thoracolumbar region were shown and reviewed. RESULTS There were approximately 21 pairs of segmental arteries in the thoracolumbar region. Adjacent segmental arteries were networked with each other. The latex infusion specimens demonstrated 72 anterior radiculomedullary arteries and 177 posterior radiculomedullary arteries in all 20 samples. The anterior and posterior spinal arteries were also networked with each other at several levels. Superselective spinal angiography was consistent with the latex infusion specimens showing. CONCLUSIONS The variety of anatomy of spinal cord arterial networks is shown, and the relation between the blood supply of certain spinal levels and the potential ischemic complications during the anterior surgical approach is discussed. It is hopefully of benefit to surgeons, after fully understanding the anatomy of these spinal vascular supply structures, that there may be even greater avoidance of vascular compromise in these challenging operations.

Epidemiological Characteristics of Traumatic Spinal Cord Injury in Guangdong, China.

Study Design. A hospital-based retrospective epidemiological study. Objective. The aim of this study was to examine the demographic and epidemiological characteristics of patients with traumatic spinal cord injury (TSCI) in Guangdong to help health-related institutions develop measures to determine the best allocation of medical resources. Summary of Background Data. TSCI is a highly disabling and deadly injury. Currently, there is little information regarding the epidemiological characteristics for TSCI in Guangdong. Methods. We retrospectively reviewed the medical records of partial second-grade class-A hospitals (mainly capturing general city and county hospitals and some large-scale affiliated hospitals) in Guangdong province according to the International Classification of Disease Version 10 (ICD-10) and diagnostic code of TSCI. Results. The study included the medical records of 1340 patients with TSCI, and the annual number of TSCI admissions increased during the 2003 to 2011 period. The male-to-female ratio was approximately 3.5:1. The major causes of spinal cord injuries were high falls (41.0%) and traffic accidents (37.8%). The most common injury among patients with TSCI was cervical injury (818 cases). In addition, 62.9% of the patients had spinal fractures, 24.0% had other fractures, and 13.7% had brain injuries. Furthermore, 25.1% (337/1340) of the patients experienced clinical complications. The differences in the number of patients with and without complete injury who accepted surgery and hyperbaric oxygen therapy were statistically significant (P < 0.05), and the difference in total medical cost was significant (P < 0.05). Conclusion. There are specific epidemiological characteristics of TSCI patients in Guangdong, and preventive measures are suggested to focus on high-risk populations, such as adult men. Level of Evidence: 3

Whole Genome Expression Profiling and Signal Pathway Screening of MSCs in Ankylosing Spondylitis

The pathogenesis of dysfunctional immunoregulation of mesenchymal stem cells (MSCs) in ankylosing spondylitis (AS) is thought to be a complex process that involves multiple genetic alterations. In this study, MSCs derived from both healthy donors and AS patients were cultured in normal media or media mimicking an inflammatory environment. Whole genome expression profiling analysis of 33,351 genes was performed and differentially expressed genes related to AS were analyzed by GO term analysis and KEGG pathway analysis. Our results showed that in normal media 676 genes were differentially expressed in AS, 354 upregulated and 322 downregulated, while in an inflammatory environment 1767 genes were differentially expressed in AS, 1230 upregulated and 537 downregulated. GO analysis showed that these genes were mainly related to cellular processes, physiological processes, biological regulation, regulation of biological processes, and binding. In addition, by KEGG pathway analysis, 14 key genes from the MAPK signaling and 8 key genes from the TLR signaling pathway were identified as differentially regulated. The results of qRT-PCR verified the expression variation of the 9 genes mentioned above. Our study found that in an inflammatory environment ankylosing spondylitis pathogenesis may be related to activation of the MAPK and TLR signaling pathways.

Quantitative assessment of spinal cord perfusion by using contrast-enhanced ultrasound in a porcine model with acute spinal cord contusion

Objectives:To quantify spinal cord perfusion by using contrast-enhanced ultrasound (CEUS) in a porcine model with acute spinal cord injury.Methods:Microcirculatory changes of acute spinal cord injury were shown by CEUS in a porcine model with spinal cord contusion at three selected time points, coupling with conventional ultrasound (US) and Color Doppler US (CDFI). Time-intensity curves and perfusion parameters were also obtained by autotracking contrast quantification (ACQ) software in the epicenter of contusion site, adjacent region and distant region, respectively. Neurologic and histologic examinations were used to confirm the severity of injury.Results:Conventional US revealed the spinal cord was hypoechoic and homogeneous, whereas the dura mater, pia mater and cerebral aqueduct were hyperechoic. On CDFI intramedullary blood vessels were displayed as segmental and columnar. It was homogeneous on CEUS. After spinal cord contusion, the injured region on gray scale US was hyperechoic. CDFI demonstrated intramedullary blood vessels of adjacent region had increased and dilated during the observation period. On CEUS the epicenter of contusion site was hypoperfusion, whereas its adjacent region was hyperperfusion compared with the distant region. Quantitative analysis showed that peak intensity decreased in epicenters of contusion but increased in adjacent regions significantly at all time points (P<0.05). Evaluation of neurological function for post-contusion demonstrated significantly deterioration in comparison before injury (P<0.05).Conclusions:CEUS is a practical technique that provides overall views for evaluating microcirculatory pattern in spinal cord injury. Quantitative analysis shows the efficacy in assessment of perfusion changes after spinal cord injury.

The Role of Increased Frequency of Treg Cells in Patients with Chronic Osteomyelitis

The aim of this study is to determine whether regulatory T cells (Treg cells) are increased in patients with chronic osteomyelitis and whether they suppress cellular immune responses to the bacteria. The frequency of circulating CD4(+)CD25(+) and CD4(+)CD25(+)FoxP3(+) T cells in 30 chronic osteomyelitis patients were compared with 30 healthy donors. Treg-depleted PBMCs from the patients were cultured together with autologous antigen, unfractioned PBMCs used as the control. The cell proliferation and production of IL-10 and IFN-γ were compared with those of the control. The results demonstrated that frequencies of CD4(+)CD25(+) (10.85±2.82% vs 6.08±1.62%, P<.001) and CD4(+)CD25(+)FoxP3(+) T cells (2.06±0.83% vs 1.43%±0.51%, P<.001) in blood from chronic osteomyelitis patients were significantly higher than in healthy donors. The level of IL-10 (117±91 pg/ml vs 323±189 pg/ml, P<.001) in supernatants of Treg-depleted PBMCs was decreased. Cell proliferation (4489±11876 cpm vs 3547±1517 cpm, P<.05) and IFN-γ (875±203 pg/ml vs 405±129 pg/ml, P<.001) production by CD4(+)CD25(+) T cell in response to antigen was significantly inhibited by CD4(+)CD25(+) T cells. These results indicate that specific Tregs can depress the T cell mediated immune responses to bacteria in chronic osteomyelitis, and may play an important role in the persistence of bacteria.

Using primate neural stem cells cultured in self-assembling peptide nanofiber scaffolds to repair injured spinal cords in rats

Study design:Transplanted primates’ neural stem cells (NSCs) tissue engineering complex into spinal cord injury (SCI) model rats, analyze and evaluate the long-term effects of repairing.Objectives:Primate NSCs were cultured in self-assembling peptide nanofiber scaffolds to repair SCI.Setting:Sun Yat-sen Memorial Hospital, Guangzhou, China.Methods:Primate NSCs were isolated and cultured in self-assembling peptide nanofiber scaffolds. T10 SCI model was established; the rats were randomly divided into four groups: NSC plus self-assembling peptide scaffold group; NSC group; self-assembling peptide scaffold group; and control group. Immunohistochemical staining and electronic microscope were used to investigate the growth and differentiation of transplanted NSCs. The motor function of the hind limbs of rats was evaluated (P<0.05 was considered as statistically significant).Results:NSCs and NSCs cultured in self-assembling peptide nanofiber scaffolds could be induced to differentiation into neurons, glial cells and oligodendrocytes in vitro. The primate NSC culture was established in self-assembling peptide scaffolds. No significant difference was seen in the differentiation rate between primate NSCs cultured in self-assembling peptide nanofiber scaffolds and primate NSCs cultured in regular medium. The motor function of the hind limbs in the NSC plus self-assembling peptide scaffold group was significantly better than that of the other three groups. In addition, the NSCs of the NSC group mainly differentiated into astrocytes.Conclusion:Transplantation of primate NSCs cultured in self-assembling peptide scaffolds is efficient for repairing the injured spinal cord and for improving the motor function of spinal cord in rats.Sponsorship:The National Natural Science Foundation of China; Science and Technology Office of Guangdong Province.