Protective effect of allicin on ischemia-reperfusion injury caused by testicular torsion-detorsion in rats.

OBJECTIVE: Testicular ischemia-reperfusion induced by testicular torsion-detorsion increases the level of reactive oxygen species, leading to testicular damage. Allicin, one of the most active ingredients in garlic, is a significant exogenous antioxidant. In the research, the efficacy of allicin in treating testicular ischemia-reperfusion injury was assessed. MATERIALS AND METHODS: The study included sixty Sprague-Dawley male rats. Three groups with 20 rats per group were created as follows: control group, testicular ischemia/reperfusion-induced group, and testicular ischemia-reperfusion plus treatment with allicin group. The control group underwent a sham operation of the left testis without other interventions. In the testicular ischemia/reperfusion-induced group, rat left testis was subjected to 720° torsion for two hours and then detorsion. In the allicin-treated group, in addition to testicular ischemia-reperfusion, 50 mg/kg of allicin was injected intraperitoneally, starting immediately following detorsion. Testicular tissue samples were obtained to measure the protein expression of xanthine oxidase, which is a major source of reactive oxygen species formation, malondialdehyde level (a reliable marker of reactive oxygen species), and testicular spermatogenic function. RESULTS: Testicular ischemia-reperfusion significantly increased the expression of xanthine oxidase and malondialdehyde levels in ipsilateral testes while reducing testicular spermatogenic function. The expression of xanthine oxidase and malondialdehyde levels were significantly lower in ipsilateral testes, whereas testicular spermatogenic function in the allicin-treated group was significantly higher compared with those in the testicular ischemia-reperfusion group. CONCLUSIONS: Our findings indicate that allicin administration improves ischemia/reperfusion-induced testicular damage by limiting reactive oxygen species generation via inhibition of xanthine oxidase expression.

Relationships of Hypnotics with Incident Dementia and Alzheimer's Disease: A Longitudinal Study and Meta-Analysis.

BACKGROUND: Evidence describing the association between hypnotics use and dementia risk is conflicting. It is unknown if the controversy is related to the type or dose of hypnotics or if hypnotics affect different populations. OBJECTIVES: We sought to derive lessons learned and future projections based on evidence from longitudinal studies. MEASUREMENTS: In the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort, 1,543 older adults without dementia (mean age = 73.3 years, female = 45%) were followed for four years. The association between hypnotics and the risk of Alzheimer's disease (AD) was investigated using Cox proportional hazards regressions. Next, electronic databases were searched until March 2022 to conduct the evidence synthesis of the associations of hypnotics with incident risk of dementia. RESULTS: In the ADNI cohort, ever use of hypnotics was associated with an increased risk of AD (hazard ratio = 1.96, 95% confidence intervals = 1.23-3.11, p < 0.01). This association was significant for benzodiazepines and Z-drugs but not for melatonin. The association was stronger in long-term (more than one year) users and those with high cumulative doses. A meta-analysis of 26 longitudinal studies with 3,942,018 participants revealed a correlation between the use of hypnotics and the risk of dementia (relative risk = 1.23, 95% confidence intervals = 1.13-1.33, p < 0.001, median risk difference = 4%). It is a linear dose-response relationship, if a person takes the daily recommended dose for 100 days, their risk of developing dementia increases by 5% relative to non-users. According to subgroup analyses, neither association was significant among patients with a history of insomnia. CONCLUSIONS: Individuals who use hypnotics, especially high-dose or long-term users, are at a higher risk of dementia and AD. The main issue with conclusion credibility is heterogeneity.

Clinicopathologic features and outcome of cervical cancer: implications for treatment.

OBJECTIVE: We used a regression analysis of the SEER database to establish a new Nomogram for predicting prognosis of cervical cancer patients and guiding the treatment. PATIENTS AND METHODS: We divided the data into the training cohort and the verification cohort. Univariate and multivariate Cox risk regression analysis was used to identify independent prognostic factors and establish a Nomogram model. The verification cohort was used for external verification, and the accuracy was evaluated with C-index and AUC. Finally, Nomogram was used to establish 1-year, 3-year and 5-year survival curves of cervical cancer patients. RESULTS: In this study, 5691 patients with cervical squamous cell carcinoma were included. Data obtained from the training cohort were independent risk factors of cervical cancer AJCC stage (p = 0.039), RX Summ - Surgery Primary Site (p = 0.012), radiation (p = 0.031), chemotherapy (p = 0.013), tumor size (p = 0.009), race (p = 0.039). The 1-year, 3-year, and 5-year overall survival rates for cervical cancer patients were 77.2%, 47.8%, and 35.2%, respectively. CONCLUSIONS: The Nomogram model can better screen out more reasonable comprehensive treatments for patients at different stages. And it is of great help to improve the survival rate and reduce the recurrence rate of cervical cancer patients.

LncRNA FOXC2-AS1 stimulates proliferation of melanoma via silencing p15 by recruiting EZH2.

OBJECTIVE: The aim of this study was to elucidate the role of FOXC2-AS1 in promoting the proliferative ability and inhibiting apoptosis of melanoma by silencing p15, thereafter regulating the progression of melanoma. PATIENTS AND METHODS: FOXC2-AS1 levels in melanoma patients with or without metastasis and those with the tumor in different stages were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Regulatory effects of FOXC2-AS1 on viability and apoptosis in melanoma cells were assessed, and subcellular distribution of FOXC2-AS1 was analyzed. Subsequently, the interactions of FOXC2-AS1 with EZH2 and SUZ12 were explored by RNA-Binding Protein Immunoprecipitation (RNA-RIP) assay. Through chromatin immunoprecipitation (ChIP) assay, the role of FOXC2-AS1 to regulate p15 transcription by recruiting EZH2 was verified. At last, regulatory effects of FOXC2-AS1/p15 axis on viability and apoptosis in melanoma cells were investigated. RESULTS: It was found that FOXC2-AS1 was upregulated in melanoma tissues, especially those with metastasis or stage II-IV. Melanoma patients expressing high level of FOXC2-AS1 showed worse survival than those with low level. Knockdown of FOXC2-AS1 inhibited viability, and stimulated apoptosis in A375 and sk-mel-110 cells. Besides, P15 level was upregulated in melanoma cells transfected with si-FOXC2-AS1, and FOXC2-AS1 was mainly distributed in cytoplasm. RNA-RIP assay confirmed that FOXC2-AS1 was mainly enriched in anti-EZH2 and aniti-SUZ12. Knockdown of EZH2 could markedly upregulate protein level of p15 in melanoma cells. Furthermore, it was verified that FOXC2-AS1 inhibited p15 transcription via recruiting EZH2, and the knockdown of p15 could partially reverse the regulatory effects of FOXC2-AS1 on viability and apoptosis in melanoma. CONCLUSIONS: FOXC2-AS1 stimulates proliferative ability in melanoma via silencing p15.

Gemcitabine combined with cisplatin vs. taxane, cisplatin, and fluorouracil in the treatment of locally advanced nasopharyngeal carcinoma: a retrospective case-control study.

OBJECTIVE: Reports of the efficacy of induction chemotherapy (IC) combined with concurrent chemoradiotherapy (CCRT) on locoregionally advanced nasopharyngeal carcinoma (NPC) are scarce. This study aimed to compare the clinical outcomes of the GP (gemcitabine plus cisplatin) regimen and the TPF (taxane, cisplatin and 5-FU) regimen combined with CCRT in patients with NPC. PATIENTS AND METHODS: This study retrospectively analyzed 827 patients with advanced NPC who received IC combined with CCRT in People's Hospital of Rizhao, China from January 2006 to June 2012. The propensity score method was used to reduce the effects of the observed confounding between the GP and TPF groups. Study end points were disease-free survival (DFS) and overall survival (OS). In total, 694 patients received GP or TPF as the IC treatment program. Propensity score matching identified 166 patients in each cohort. RESULTS: The 5-year OS and DFS rates of the entire cohort were 83.5% and 80.9%, respectively. GP was associated with a significantly improved 5 year OS (87.4% vs. 79.2%, p< 0.001), and DFS (86.2% vs. 78.5%, p< 0.001) rates compared with the TPF group. In the PSM (propensity score-matching) cohort, the GP group showed a significantly better OS (HR, 1.842, 95% CI:1.627-2.588; p= 0.011), and DFS (HR, 1.904, 95% CI: 1.742-2.737; p= 0.004) compared with the TPF group in multivariable analyses. The prevalence of acute adverse events of neutropenia and leukopenia were higher in severe (grade 3-4) adverse blood events in the TPF group (p<0.05). Thrombocytopenia had more adverse reactions in the GP group (p<0.05). The main non-hemotoxicities were nausea and vomiting, while the TPF group was slightly higher (p=0.031). CONCLUSIONS: The clinical efficacy of the GP regimen combined with CCRT for the treatment of locoregionally advanced NPC may be better than that of the TPF regimen.

LncSNHG14 promotes ovarian cancer by targeting microRNA-125a-5p.

OBJECTIVE: This study aims to investigate whether small nucleolar RNA host gene 14 (SNHG14) is involved in the development of ovarian cancer through affecting cell proliferation and cell cycle progression by regulating microRNA-125a-5p. PATIENTS AND METHODS: We detected the mRNA expressions of SNHG14 and microRNA-125a-5p by quantitative Polymerase Chain Reaction (qPCR) in ovarian cancer tissues and normal ovarian tissues. Their expression levels in ovarian cancer cell lines were examined as well. Meanwhile, the regulatory effects of SNHG14 and microRNA-125a-5p on cell proliferation and cell cycle were detected by Cell Counting Kit-8 (CCK-8) and flow cytometry, respectively. The binding relationship between microRNA-125a-5p and SNHG14 was examined by the Luciferase reporter gene assay. It was further confirmed by recovery experiments whether SHHG14 can affect the proliferation and cycle of ovarian cancer cells by regulating microRNA-125a-5p. RESULTS: SNHG14 was highly expressed in ovarian cancer tissues and cell lines relative to controls. The survival curve analysis showed that the AUC was 0.8681 and Cutoff value was 2.33. The five-year survival rate of the high SNHG14 expression group was markedly lower than that of the low SNHG14 expression group. In addition, we found that SNHG14 could accelerate cell proliferation and cell cycle progression of ovarian cancer cells. Dual-Luciferase reporter gene experiments indicated that SNHG14 could bind to microRNA-125a-5p, which was lowly expressed in ovarian cancer patients. However, the overexpression of microRNA-125a-5p reversed the promotive effect of SNHG14 on the proliferation and cell cycle of ovarian cancer cells. Dual-Luciferase reporter gene assay also indicated that DHX33 was a target gene of microRNA-125a-5p. The overexpression of DHX33 could attenuate the inhibitory effect of microRNA-125a-5p on cell proliferation and cell cycle in SKOV3 and OVCAR3 cells. CONCLUSIONS: High expression of SNHG14 can promote the ovarian cancer cell proliferation and accelerate the cell cycle by sponging microRNA-125a-5p to regulate DHX33 expression.

FAMLF is a target of miR-181b in Burkitt lymphoma

Burkitt lymphoma (BL) is a highly malignant non-Hodgkin's lymphoma that is closely related to the abnormal expression of genes. Familial acute myelogenous leukemia related factor (FAMLF; GenBank accession No. EF413001.1) is a novel gene that was cloned by our research group, and miR-181b is located in the intron of the FAMLF gene. To verify the role of miR-181b and FAMLF in BL, RNAhybrid software was used to predict target site of miR-181b on FAMLF and real-time quantitative PCR (RQ-PCR) was used to detect expression of miR-181b and FAMLF in BL patients, Raji cells and unaffected individuals. miR-181b was then transfected into Raji and CA46 cell lines and FAMLF expression was examined by RQ-PCR and western blotting. Further, Raji cells viability and proliferation were detected by MTT and clone formation, and Raji cell cycle and apoptosis were detected by flow cytometry. The results showed that miR-181b can bind to bases 21–42 of the FAMLF 5′ untranslated region (UTR), FAMLF was highly expressed and miR-181b was lowly expressed in BL patients compared with unaffected individuals. FAMLF expression was significantly and inversely correlated to miR-181b expression, and miR-181b negatively regulated FAMLF at posttranscriptional and translational levels. A dual-luciferase reporter gene assay identified that the 5′ UTR of FAMLF mRNA contained putative binding sites for miR-181b. Down-regulation of FAMLF by miR-181b arrested cell cycle, inhibited cell viability and proliferation in a BL cell line model. Our findings explain a new mechanism of BL pathogenesis and may also have implications in the therapy of FAMLF-overexpressing BL.

Role of Ion Kinetic Physics in the Interaction of Magnetic Flux Ropes.

To explain many natural magnetized plasma phenomena, it is crucial to understand how rates of collisionless magnetic reconnection scale in large magnetohydrodynamic (MHD) scale systems. Simulations of isolated current sheets conclude such rates are independent of system size and can be reproduced by the Hall-MHD model, but neglect sheet formation and coupling to MHD scales. Here, it is shown for the problem of flux-rope merging, which includes this formation and coupling, that the Hall-MHD model fails to reproduce the kinetic results. The minimum sufficient model must retain ion kinetic effects, which set the ion diffusion region geometry and give time-averaged rates that reduce significantly with system size, leading to different global evolution in large systems.

Tissue-direct PCR, a rapid and extraction-free method for barcoding of ferns.

Fern gametophytes and young sporophytes often provide too little material for DNA extraction and are particularly difficult to identify to genus. Here we developed an efficient procedure called 'Tissue-direct PCR', in which a slice of fern tissue is mixed with PCR reagents and primers, allowing certain genomic regions to be amplified directly in the thermal cycler. For these diminutive and featureless stages of ferns, Tissue-direct PCR combined with amplifying plant barcodes promises to make the identification of immature ferns easy and rapid. Tissue-direct PCR would also be very helpful for large-scale ecological studies surveying distribution and population structure.

Association of TNF-alpha gene polymorphisms with systemic lupus erythematosus in Taiwanese patients.

Tumour necrosis factor-alpha (TNF-alpha), an important proinflammatory cytokine, exerts a variety of physiological and pathogenic effects that lead to tissue destruction. Studies on the association of TNF-alpha genetic polymorphisms with systemic lupus erythematosus (SLE) have yielded inconclusive results. We investigated the association of TNF-alpha genetic polymorphisms (-1031T/C, -863C/A, -857T/C, -308A/G and +489A/G) with SLE in Taiwanese patients and controls. Our results indicate that 1) the frequency of the A-allele at -863 position was significantly higher in SLE patients (odds ratio = 1.46; 95% CI = 1.02-2.08); 2) the frequency of the A-allele at +489 position was significantly higher in SLE patients (odds ratio = 1.79; 95% CI = 1.21-2.65); 3) the AA or GA genotype frequencies at +489 position were significantly increased in SLE patients (AA genotype: odds ratio = 11.20; 95% CI = 1.36-92.55; GA genotype: odds ratio = 1.63; 95% CI = 1.03-2.58); 4) no significant association of TNF-alpha haplotypic distributions was observed, except for the haplotypes TCCGA, CACGA and CCCGG; and 5) the genotype frequency of the polymorphisms at -1031 was significantly different in patients with antinuclear antibodies (P = 0.022). The allele and genotype frequencies of the polymorphisms at -863 were not significantly different. The genotype frequency of the polymorphisms at -857 was significantly different in patients with haematological disorder (P = 0.025). The frequency of A allele of the polymorphisms at -308 was significantly increased in patients with malar rash (P = 0.033), discoid rash (P = 0.023), photosensitivity (P = 0.037), oral ulcers (P = 0.002) and serositis (P = 0.029). The genotype frequency of the polymorphisms at +489 was significantly different in patients with discoid rash and photosensitivity (data not shown; discoid rash, P = 0.031; photosensitivity, P = 0.044). These results suggest that TNF-alpha genetic polymorphisms contribute to SLE susceptibility in the Taiwanese population.

HLA-E gene polymorphism associated with susceptibility to Kawasaki disease and formation of coronary artery aneurysms.

OBJECTIVE: Kawasaki disease (KD) is a pediatric systemic vasculitis of unknown cause for which a genetic influence is supposed. The purpose of this study was to identify possible genetic variants in the major histocompatibility complex (MHC) region that are associated with KD and the development of coronary artery aneurysms (CAAs) in a Taiwanese population. METHODS: The 168 genetic variants covering the MHC locus were analyzed in an association study of a Taiwanese cohort of 93 KD patients and 680 unrelated healthy children matched for sex and age with the study patients. RESULTS: Eleven single-nucleotide polymorphisms (SNPs) were associated with the occurrence of KD. The SNP located at the 3'-untranslated region of HLA-E (rs2844724) was highly associated (P < 1 x 10(-7)). In addition, the frequency of the C allele was higher in KD patients without CAAs than in controls (P < 0.001) due to a significantly increased frequency of the CC and CT genotypes. Plasma levels of soluble HLA-E were significantly higher in KD patients than in controls regardless of the presence of CAAs. Furthermore, there was a trend toward higher plasma levels of soluble HLA-E in KD patients with the CT and TT genotypes of the HLA-E gene polymorphism. CONCLUSION: Our results suggest that the HLA-E gene polymorphism may play a role in the pathogenesis of KD.

Factors predicting mortality in victims of blunt trauma brain injury in emergency department settings.

OBJECTIVE: The aim of the study was to identify risk factors for mortality in patients brought to the emergency department (ED) after blunt traumatic brain injury (TBI). METHODS: The medical records of such patients who visited the ED from June 2004 to May 2005 were retrospectively reviewed. Data (age, gender, initial Glasgow coma scale (GCS) scores, initial vital signs, brain computed tomography scan findings and cause of trauma) were collected from the records of 204 TBI patients, who were treated at the ED and needed intensive care. Among these patients, 48 died in the intensive care unit (ICU) of the hospital. Logistic regression was used to assess factors affecting mortality after trauma. RESULTS: Age (odds ratio (OR) 1.04; 95% CI 1.01 to approximately 1.07), GCS score less than 9 (OR 19.29; 95% CI 5.04 to approximately 73.82) and skull bone fracture (OR 10.44; 95% CI 3.59 to approximately 30.38) were identified as possible risk factors of mortality in TBI patients. CONCLUSION: These predictors appear to be clinically relevant and may help improve ED triage of TBI patients in need of ICU care.

Glycosyl bis-porphyrin conjugates: synthesis and potential application in PDT.

Syntheses of new glycosylated neutral and cationic porphyrin dimers linked at the meso-position via a flexible hydrocarbon chain are described. A detailed 1H and 13C NMR study allows their complete structural elucidation. The UV-visible, fluorescence and MALDI mass spectra are also presented. Photocytotoxicities of these compounds against K562 leukaemia cell line are compared to those of Photofrin II.

Glatiramer acetate reduces lymphocyte proliferation and enhances IL-5 and IL-13 production through modulation of monocyte-derived dendritic cells in multiple sclerosis.

Dendritic cells (DC), as the most effective antigen presenting cells, are protagonists of the complex immune network involved in multiple sclerosis (MS) lesion formation. Glatiramer acetate (GA), a synthetic random copolymer, is thought to exert its therapeutical effect in MS by favouring both Th2 cell development and IL-10 production from peripheral lymphocytes as well as by systemically affecting the antigen presenting cells. In the present study we further analysed the mechanisms of action of GA by using an autologous DC-lymphocytes (Ly) coculture system from 11 MS patients and 12 matched healthy controls (HC). We found that, in MS patients, pretreatment with GA significantly decreases the in vitro proliferative effect of DC on lymphocytes as compared to HC and to unpulsed or myelin basic protein (MBP)-pulsed DC from MS patients (P < 0.05). In addition, GA-treated DC from both MS patients and HC significantly increase the lymphocyte production of IL-5 and IL-13 as compared to MBP-treated DC (P < 0.05). In conclusion our in vitro study may provide new therapeutical mechanisms of GA on lymphocytes, antiproliferative and Th2-favouring effects, which are mediated by monocyte-derived DC.

Dendritic cells in the cerebrospinal fluid and peripheral nerves in Guillain-Barré syndrome and chronic inflammatory demyelinating polyradiculoneuropathy.

The role of antigen-presenting cells (APC) involved in induction of T and B cell mediated autoaggressive immunity in Guillain-Barre syndrome (GBS) and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is poorly understood. We studied the numbers and phenotype of dendritic cells (DC) in blood and cerebrospinal fluid (CSF) over the course of GBS and CIDP before and after immunomodulatory treatment. Four out of seven GBS patients examined prior to treatment with high-dose intravenous immunoglobulins (IvIg) had elevated numbers of CD123(+) plasmacytoid DC in the CSF, while both GBS and CIDP patients examined prior to treatment had elevated numbers of CD11c(+) myeloid DC in the CSF, as compared to patients with noninflammatory neurological diseases (OND). The percentages of blood DC expressing the cell surface marker CD1a, co-stimulatory molecules CD80 and CD86, adhesion molecule CD54, and chemokine receptors CCR1, CCR2, CCR5, and CXCR4 were not affected in GBS or CIDP. The immunohistochemistry of sural nerve biopsies revealed CD11c(+)CD83(-)CD14(-)CD16(-) immature myeloid DC at low numbers, mostly in the perineurium, without difference between CIDP patients and controls. In contrast, the numbers of CD11c(+)CD14(+)/CD16(+) macrophages were higher within the endoneurium in CIDP patients compared with the controls. The recruitment of DC to CSF in GBS and CIDP may be important in capturing antigens released from inflamed spinal nerve roots into CSF and in transferring these antigens from CSF to local lymph nodes, where naive T and B cells may be activated.

Interferon-gamma-modified dendritic cells suppress B cell function and ameliorate the development of experimental autoimmune myasthenia gravis.

This study was designed to investigate the therapeutic effects of interferon (IFN)-gamma-modulated dendritic cells (DC) in experimental autoimmune myasthenia gravis (EAMG). We induced EAMG in Lewis rats by immunization with Torpedo nicotinic acetylcholine receptor (nAChR) and adjuvant. On day 33 post-immunization (p.i.), splenic DC were prepared, exposed to IFN-gamma alone (IFN-gamma-DC) or to IFN-gamma in combination with 1-methyl-DL-tryptophan (1-MT), the specific inhibitor of indoleamine 2,3-dioxygenase (IDO) (IFN-gamma + 1-MT-DC), and injected subcutaneously into rats with incipient EAMG on day 5 p.i. A control group of EAMG rats received naive DC on day 5 p.i., while another group received 1-MT every other day, intraperitoneally (p.i.), from days 5 to 41 p.i. The severity of clinical signs of EAMG was reduced dramatically in IFN-gamma-DC-treated rats compared to rats receiving naive DC, IFN-gamma + 1-MT-DC or 1-MT alone. The number of plasma cells secreting nAChR antibodies was reduced and the expression of B cell activation factor (BAFF) on splenic and lymph node mononuclear cells (MNC) was down-regulated in rats treated with IFN-gamma-DC. In vitro co-culture of MNC derived from EAMG rats with IFN-gamma-DC produced relatively few cells secreting nAChR antibodies. Addition of 1-MT to the co-culture significantly increased the number of cells secreting nAChR antibodies. We conclude that IFN-gamma-DC reduced the number of plasma cells secreting nAChR antibodies in an IDO-dependent manner and ameliorated the development of EAMG in Lewis rats.

CD8alpha dendritic cells and immune protection from experimental allergic encephalomyelitis.

Dendritic cells (DC) represent a phenotypically heterogeneous population endowed with two important biological functions, immunity and tolerance. Here we report that the injection of splenic CD8alpha(+) DC, derived from rats with experimental allergic encephalomyelitis (EAE), delayed the onset and suppressed the severity of EAE in Lewis rats. This was accompanied by the lack of magnetic resonance imaging (MRI) lesions in the brain and spinal cord and by reduced numbers of inflammatory cells within the central nervous system. Injection of CD8(alpha+) DC inhibited T cell proliferation that may relate to increased interferon (IFN)-gamma and nitric oxide production. Although CD8(+)CD28(-) suppressor T cells, apoptotic cells and co-stimulatory molecules were not altered, CD4(+) T cells expressing interleukin (IL)-10 were augmented in rats receiving CD8alpha(+) DC compared to rats receiving total DC or medium. These results demonstrate that rat splenic CD8alpha(+) DC could provide a cellular basis for a novel, individualized immunotherapy using autologous DC as a complement to conventional therapy in diseases with an autoimmune background such as multiple sclerosis.

Interleukin-10-modulated immature dendritic cells control the proinflammatory environment in multiple sclerosis.

Multiple sclerosis (MS) is a disabling, inflammatory, demyelinating disease of the central nervous system considered to be mediated by autoreactive T cells. Dendritic cells (DC), being professional antigen-presenting cells, play a pivotal role in the decision between T-cell activation and anergy. It has been suggested that mature DC (mDC) induce immunity, whereas immature DC (imDC) have the potential to induce tolerance. In this study, we investigated the effects of autologous imDC versus autologous mDC on lymphocytes with respect to the expression of functionally important cell-surface molecules and production of cytokines. Our aims were to investigate whether the maturation status of DC differs between MS and healthy controls (HC) and to explore whether the effects of DC on T-cell responses differ between MS and HC. DC were generated from adherent blood mononuclear cells from patients with MS and HC. imDC were obtained by culture with either granulocyte-macrophage colony-stimulating factor (GM-CSF) + interleukin-4 (IL-4) or GM-CSF + IL-4 + IL-10. mDC were obtained by adding lipopolysaccharide to DC cultures. Upon coculture with autologous lymphocytes, mDC activated the autologous T cells as reflected by increased CD25 and cytotoxic T-lymphocyte antigen-4 expression on CD4(+) T cells together with the increased production of both T helper 1 (Th1) (IL-2 and interferon-gamma) and Th2 (IL-10 and IL-4) cytokines. Unmodulated naïve imDC induced the production of only IL-4. An exposure of imDC to IL-10 induced the production of IL-4 as well as IL-10 by autologous lymphocytes. We hypothesize that such imDC are important in controlling the proinflammatory environment in vivo in patients with MS.

Circulating CD4+CD25+ and CD4+CD25+ T cells in myasthenia gravis and in relation to thymectomy.

Studies in experimental animal models of human autoimmune diseases have revealed that CD4(+)CD25(+) T regulatory (Tr) cells are of thymic origin and have potentials in preventing auto-aggressive immunity. Myasthenia gravis (MG) is the best-characterized autoimmune disease. Changes in the thymus are found in a majority of patients with MG. Thymectomy has beneficial effects on the disease severity and course in a substantial proportion of MG patients. But the occurrence and characteristics of Tr cells have not yet been defined in MG. We determined the frequencies and properties of circulating CD4(+)CD25(+) versus CD4(+)CD25(-) cells in MG patients and healthy controls (HCs), with special focus on the effect of thymectomy on CD4(+)CD25(+) cells. CD4(+)CD25(high) cells comprise only about 2% of blood lymphocytes in both MG patients and HCs. Frequencies of CD4(+)CD25(high) cells were similar in MG patients irrespective of treatment with thymectomy. CD4(+)CD25(+) cells in both MG patients and HCs are mainly memory T cells and are activated to a greater extent than CD4(+)CD25(-) cells, as reflected by high levels of CD45RO and human leucocyte antigen (HLA)-DR-positive cells. In both MG patients and HCs, CD4(+)CD25(+) cells also contained a high proportion of CD95-expressing cells as possible evidence of apoptosis-proneness. Upon stimulation with anti-CD3/CD28 monoclonal antibodies, CD4(+)CD25(+) cells responded more vigorously than CD4(+)CD25(-) cells in MG, irrespective of treatment with thymectomy, as well as in HCs. Although CD4(+)CD25(-) cells are mainly naïve T cells, in non-thymectomized MG patients, they are activated to a greater extent as reflected by higher expression of HLA-DR and CD95 on the surface compared to HCs. The data thus show that there is no deficiency of CD4(+)CD25(+) cells in MG, nor is the proportion of CD4(+)CD25(+) cells influenced by thymectomy.

Multiple sclerosis: a study of chemokine receptors and regulatory T cells in relation to MRI variables.

Magnetic resonance imaging (MRI) remains the most valuable tool for monitoring disease activity and progression in patients with multiple sclerosis (MS), a chronic demyelinating disease of the central nervous system (CNS) with presumably autoimmune etiology. Chemokine receptors have been implicated in MS as key molecules directing inflammatory cells into the CNS. Regulatory (CD4+CD25+) T cells (Tr cells) are important in suppressing autoimmunity, and their absolute or functional deficit could be expected in MS. In the present study, venous blood was obtained from MS patients concurrent with MRI examination of the brain, and expression of chemokine receptors CCR1, CCR2, CCR5, CXCR3 and CXCR4 by CD4 T cells and monocytes, proportions of Tr cells, as well as expression of CD45RO, CD95, CTLA-4, HLA-DR and interleukin (IL)-10 by Tr cells and non-Tr (CD25-) CD4 T cells was analyzed by flow cytometry. Surface expression of CXCR3 by CD4 T cells was downregulated in the group of patients with high lesion load (LL) on T2-weighted images and gadolinium (Gd)-enhancing lesions on T1-weighted images, compared to the group with high LL and no Gd-enhancing lesions, and to the group with low LL, suggesting internalization of CXCR3 due to the release of its chemokine ligand (IP-10/CXCL10) from active MS lesions. Proportions of Tr cells amongst all CD4 T cells, and expression of IL-10 by Tr cells were increased in the patients with high LL and Gd-enhancing lesions. These results suggest that there is correlation between MRI parameters, chemokine receptor expression and the status of circulating Tr cells in MS, but further studies need to discriminate between pathogenetically relevant and bystander phenomena.