Memory B cells from a subset of treatment‐naïve relapsing‐remitting multiple sclerosis patients elicit CD4+ T‐cell proliferation and IFN‐γ production in response to myelin basic protein and myelin oligodendrocyte glycoprotein

Recent evidence suggests that B‐ and T‐cell interactions may be paramount in relapsing‐remitting MS (RRMS) disease pathogenesis. We hypothesized that memory B‐cell pools from RRMS patients may specifically harbor a subset of potent neuro‐APC that support neuro‐Ag reactive T‐cell proliferation and cytokine secretion. To test this hypothesis, we compared CD80 and HLA‐DR expression, IL‐10 and lymphotoxin‐α secretion, neuro‐Ag binding capacity, and neuro‐Ag presentation by memory B cells from RRMS patients to naïve B cells from RRMS patients and to memory and naïve B cells from healthy donors (HD). We identified memory B cells from some RRMS patients that elicited CD4⁺ T‐cell proliferation and IFN‐γ secretion in response to myelin basic protein and myelin oligodendrocyte glycoprotein. Notwithstanding the fact that the phenotypic parameters that promote efficient Ag presentation were observed to be similar between RRMS and HD memory B cells, a corresponding capability to elicit CD4⁺ T‐cell proliferation in response to myelin basic protein and myelin oligodendrocyte glycoprotein was not observed in HD memory B cells. Our results demonstrate for the first time that the memory B‐cell pool in RRMS harbors neuro‐Ag specific B cells that can activate T cells.     

Circulating CD3+ CD4+ CD+ T lymphocytes in multiple sclerosis

Triple-antibody flow cytometry was used to search for distinctive populations of peripheral blood lymphocyte immunophenotypes in multiple sclerosis (MS). Using monoclonal antibodies to the cell surface markers CD3, CD4, and CD8, T cell subsets were quantified on a cohort of 31 MS patients (not treated with corticosteroids for at least 6 months), 30 healthy donors, and 14 patients with other autoimmune diseases (also corticosteroid treatment-free for at least 6 months). Untreated MS patients displayed a significantly greater population of CD3+CD4+CD8+ circulating T cells than healthy donors (P = 0.023). Patients with other autoimmune diseases displayed mean populations of CD3+CD4+CD8+ cells greater than normal donors and less than MS, but not significantly different from either. An additional 45 MS patients who had received corticosteroid therapy within the previous 6 months were phenotyped. Treatment of symptomatic MS with corticosteroids was associated with a smaller population of circulating CD3+CD4+CD8+ cells. Some MS patients have significantly greater numbers of peripheral blood T lymphocytes simultaneously expressing CD3, CD4, and CD8 surface markers than healthy donors and this population of cells may be reduced by corticosteroids treatment. This triple positive phenotype may be a manifestation of a systemic immune abnormality in MS.     

T‐cell responses after haematopoietic stem cell transplantation for aggressive relapsing–remitting multiple sclerosis

Autologous haematopoietic stem cell transplantation (HSCT) for relapsing–remitting multiple sclerosis is a potentially curative treatment, which can give rise to long‐term disease remission. However, the mode of action is not yet fully understood. The aim of the study was to evaluate similarities and differences of the CD4⁺ T‐cell populations between HSCT‐treated patients (n = 12) and healthy controls (n = 9). Phenotyping of memory T cells, regulatory T (Treg) cells and T helper type 1 (Th1) and type 17 (Th17) cells was performed. Further, T‐cell reactivity to a tentative antigen, myelin oligodendrocyte glycoprotein, was investigated in these patient populations. Patients treated with natalizumab (n = 15) were included as a comparative group. White blood cells were analysed with flow cytometry and T‐cell culture supernatants were analysed with magnetic bead panel immunoassays. HSCT‐treated patients had similar levels of Treg cells and of Th1 and Th17 cells as healthy subjects, whereas natalizumab‐treated patients had lower frequencies of Treg cells, and higher frequencies of Th1 and Th17 cells. Cells from HSCT‐treated patients cultured with overlapping peptides from myelin oligodendrocyte glycoprotein produced more transforming growth factor‐β₁ than natalizumab‐treated patients, which suggests a suppressive response. Conversely, T cells from natalizumab‐treated patients cultured with those peptides produced more interleukin‐17 (IL‐17), IL‐1 and IL‐10, indicating a Th17 response. In conclusion, we demonstrate circumstantial evidence for the removal of autoreactive T‐cell clones as well as development of tolerance after HSCT. These results parallel the long‐term disease remission seen after HSCT.     

Simvastatin inhibits secretion of Th17‐polarizing cytokines and antigen presentation by DCs in patients with relapsing remitting multiple sclerosis

Statins, widely used cholesterol‐lowering agents, have also been demonstrated to have antiinflammatory effects. Here, we characterize the capacity of simvastatin to target DCs and modulate T‐cell priming and Th17‐cell differentiation, in a cohort of patients with relapsing remitting multiple sclerosis (RRMS). We report that simvastatin inhibits IL‐1β, IL‐23, TGF‐β, IL‐21, IL‐12p70, and induces IL‐27 secretion from DCs in RRMS patients, providing an inhibitory cytokine milieu for Th17 and Th1‐cell differentiation. The effect on DCs is mediated via induction of SOCS1, SOCS3, and SOCS7 gene expression, which are associated with the inhibition of STAT1, STAT3, and ERK1/2 phosphorylation. A geranylgeranyl transferase inhibitor replicated simvastatin's effects on DC cytokine secretion, implicating that simvastatin‐induced depletion of isoprenoids mediates this effect. Simvastatin inhibited antigen presentation by DCs via suppression of the MHC class I expression, costimulatory molecules CD80 and CD40, and by inducing a dramatic loss of dendritic processes. The changes in DC morphology were also mediated via inhibition of geranylgeranylation. The therapeutic use of geranylgeranylation inhibitors may provide selective inhibition of key pathogenic cytokines that drive the autoimmune response in MS; their use represents a promising therapeutic approach that requires further clinical testing.     

Glucocorticoid treatment restores the impaired suppressive function of regulatory T cells in patients with relapsing–remitting multiple sclerosis

Patients relapsing from multiple sclerosis (MS) are treated with high‐dose, short‐term intravenous injection of glucocorticoid (GC), although its mechanism of action remains only partly understood. We evaluated the ex vivo and in vitro effects of GC on regulatory T cell (T_reg) function in 14 relapsing–remitting MS (RR‐MS) patients in acute phase and 20 healthy controls (HC). T_reg function was enhanced significantly after 5 days of GC treatment. Furthermore, there was a trend towards increasing proportions of CD4⁺CD25⁺forkhead box P3⁺ T cells and interleukin‐10 secretion with GC treatment when compared with HC. In conclusion, GC treatment restores the impaired T_reg function in patients with RR‐MS in its acute phase.     

Ex vivo expanded regulatory T cells CD4+CD25+FoxP3+CD127Low develop strong immunosuppressive activity in patients with remitting-relapsing multiple sclerosis

Multiple sclerosis (MS) is an autoimmune disease characterized by defect in regulatory function of CD4⁺CD25⁺ T cells. We demonstrated difference in proportion of regulatory T cells CD4⁺CD25⁺FoxP3⁺CD127^low (Tregs) within the same patients’ relapse and remission. Proportion of peripheral Tregs (pTregs) dropped almost two times in the relapse compare to remission. Levels of pTregs in patients’ remission were lower than in healthy donors. Suppressive ability of pTregs was decreased in MS patients compared to healthy donors. Injections of expanded ex vivo autologous Tregs (eTregs) could be helpful in bringing up the level of Tregs in patients’ blood. We developed a simple method for ex vivo expansion of autologous Tregs within a short period of time. The final pool of cells consisted of 90-95% eTregs. When we started the culture with 10-20?×?10⁶ CD4⁺ T cells, we yield 300-400?×?10⁶ eTregs in a week. Expression of FoxP3 and Helios was calculated by two methods. Expanded ex vivo patients’ and donors’ Tregs were characterized by increased from three to five times expression of FoxP3, as well as almost doubled Helios expression. Peripheral Tregs in MS patients have decreased demethylation of FoxP3 gene promoter in comparison with donors. On the contrary, eTregs showed stable up-regulated demethylation without difference between MS patients and donors. MS patients’ and donors’ eTregs have much more suppressive ability than pTregs. Our data showed that eTregs can be applied as immunotherapy for MS patients and other autoimmune diseases if further investigated.     

Regulatory CD4+CD25+ T lymphocytes in peripheral blood from patients with atopic asthma

The aim of this study was to analyze whether regulatory CD4+CD25+ T lymphocytes exist and function normally in patients with atopic asthma. Our data showed that a significant increase in CD4+CD25+ cell numbers was seen in atopic asthmatics during acute exacerbation, but not in those stable asthmatics, atopic nonasthmatics, and normal subjects. The mean inhibition values of the proliferation response of CD4+CD25- cells by CD4+CD25+ cells from normal controls and asthmatics were almost the same. There was no difference in inhibitory effects on both Th1 and Th2 cytokine production of CD4+CD25- cells by CD4+CD25+ cells in the two groups. These data demonstrated that although CD4+CD25+ cells increase in atopic asthma during exacerbation, these regulatory T cells appear to function normally with regard to suppression of T-cell proliferation as well as Th1-Th2 cytokine production.     

自身免疫性甲状腺疾病患者外周血淋巴细胞端粒长度的研究

目的：研究自身免疫性甲状腺疾病（ATD）患者外周血淋巴细胞端粒长度的变化。方法：用流式原位杂交法检测38例ATD患者和48例健康对照者外周血淋巴细胞的端粒长度。结果：患者组外周血淋巴细胞端粒长度明显短于健康对照组（P＜0．001）,端粒长度与病程、发病时间、甲状腺激素水平不相关。健康对照组端粒长度随年龄增加而变短,病人组端粒长度与年龄不相关。结论：ATD病人的外周血淋巴细胞端粒长度比正常人短,且与年龄不相关,提示其外周血淋巴细胞复制、分裂增多及凋亡异常。     

CD127 immunophenotyping suggests altered CD4+ T cell regulation in primary progressive multiple sclerosis

Aberrant regulatory T cell populations, characterised by a wide array of CD markers, have been identified in many autoimmune diseases. CD127 has recently been identified as a specific marker for the CD4(+)CD25(Hi) (Tregs) subset. CD127 is the first non-HLA gene to have its association with multiple sclerosis widely replicated. We demonstrate that the regulatory or suppressor T cells CD4(+)CD25(Hi) (Tregs), CD8(+)CD28(-), and CD3(+)CD56(+) (NKT) all produce low levels of CD127, and so could be at a disadvantage in survival and/or proliferation where IL7 is limiting. The remissions seen in relapsing remitting multiple sclerosis (RRMS) could be driven by regulatory T cells, and the absence of remissions seen in primary progressive MS (PPMS) may point to a particularly reduced function of this cell subset. We found that the proportions of CD4(+)FoxP3(+)CD25(Hi) regulatory T cells were not aberrant in PPMS. There was, however, a trend towards reduced FoxP3 expression per cell in this fraction (p<0.083), which has been highly correlated with suppressor function. Notably, we found that the target of regulatory T cells, the CD4(+)CD25(-) cells, was in excess (p<0.009); and in PPMS a protective CD127 haplotype is correlated with higher CD127 expression (p<0.01). These data support further investigations into the regulatory T cell immunophenotype in MS.     

5′‐Ectonucleotidase/CD73 expression on lymph‐circulating lymphocytes and lymphatic endothelial cells offers new paths to explore barrier function

5′‐Nucleotidase/CD73 is a key enzyme in the regulation of purinergic signaling, hydrolyzing extracellular AMP to produce adenosine, which is critical in the blood vascular system and in immunosuppression. CD73 is expressed by both blood endothelial cells and lymphatic endothelial cells. Although the role of CD73 on blood endothelial cells in controlling vascular permeability and leukocyte trafficking has been studied, the role of lymphatic CD73 has thus far remained unknown. In this issue of European Journal of Immunology, Yegutkin et al. [Eur. J. Immunol. 2015. 45: 562–573] compare CD73 activity in the endothelia of lymphatics and blood vessels and investigate the CD73⁺ lymphocyte subpopulations possibly involved in immunoregulation. This Commentary will discuss how the authors′ work sheds light on the differential use of CD73 by these two cell populations to control endothelial permeability and sprouting.     

The identification of up‐regulated ebv‐miR‐BHRF1‐2‐5p targeting MALT1 and ebv‐miR‐BHRF1‐3 in the circulation of patients with multiple sclerosis

Epstein–Barr virus (EBV) is a well‐documented aetiological factor for multiple sclerosis (MS). EBV encodes at least 44 microRNAs (miRNAs) that are readily detectable in the circulation of human. Previous studies have demonstrated that EBV‐encoded miRNAs regulate host immune response and may serve as biomarkers for EBV‐associated diseases. However, the roles of EBV miRNAs in MS are still unknown. To fill the gap, we conducted a comprehensive profiling of 44 mature EBV miRNAs in 30 relapsing–remitting MS (RRMS) patients at relapse and 30 matched healthy controls. Expression levels of ebv‐miR‐BHRF1‐2‐5p and ebv‐miR‐BHRF1‐3 were elevated significantly in the circulation and correlated positively with the expanded disability status scale (EDSS) scores of MS patients. Receiver operating characteristic (ROC) analyses confirmed that the expression of these two miRNAs distinguished MS patients clearly from healthy controls. Luciferase assays revealed that ebv‐miR‐BHRF1‐2‐5p may directly target MALT1 (mucosa‐associated lymphoid tissue lymphoma transport protein 1), a key regulator of immune homeostasis. In conclusion, we described the expression of EBV miRNAs in MS and preliminarily validated the potential target genes of significantly altered EBV miRNAs. The findings may pave the way for prospective study about the pathogenesis of MS.     

Increased expression of CD40 ligand in activated CD4+ T lymphocytes of systemic sclerosis patients

CD40-CD154 interactions play a key role in regulating immune response and are involved in the development of some autoimmune diseases. We analysed the expression of CD154 antigen in CD3-activated PBMC from 10 systemic sclerosis (SSc) patients and 10 control subjects by immunofluorescence. PBMC from SSc patients showed an increased expression of this molecule, since, 6 h following CD3 stimulation, the percentage of CD154(+)cells was of 17. 53+/-2.0 (mean+/-SE) in control and 25.33+/-2.93 in patient cells (P< 0.03). The higher expression of CD154 antigen was ascribible to CD4(+)cells. The enhanced induction of CD154 following CD3 stimulation depended on protein synthesis, since was abolished when the cells were stimulated via CD3 in the presence of cycloheximide. By analysing the expression of the CD40-induced antigen CD80, we verified that a blocking anti-CD40 antibody inhibited CD80 appearance in SSc activated monocytes, indicating that CD154 molecule was functional. These results show an enhanced expression of a functional CD154 molecule in SSc CD4(+)activated T lymphocytes.     

Interleukin‐17‐ and interleukin‐22‐secreting myelin‐specific CD4+ T cells resistant to corticoids are related with active brain lesions in multiple sclerosis patients

Multiple sclerosis (MS) is thought to be an autoimmune disorder. It is believed that immunological events in the early stages have great impact on the disease course. Therefore, we aimed to evaluate the cytokine profile of myelin basic protein (MBP)‐specific T cells from MS patients in the early phase of the disease and correlate it to clinical parameters, as well as to the effect of in vitro corticoid treatment. Peripheral T cells from MS patients were stimulated with MBP with our without hydrocortisone for 5 days. The cytokines level were determined by ELISA. The number of active brain lesions was determined by MRI scans, and the neurological disabilities were assessed by Expanded Disability Status Scale scores. Our results demonstrated that MS‐derived T cells responded to MBP by producing high levels of T helper type 1 (Th1) and Th17 cytokines. Although the production of interleukin‐6 (IL‐6), granulocyte–macrophage colony‐stimulating factor, IL‐17 and IL‐22 was less sensitive to hydrocortisone inhibition, only IL‐17 and IL‐22 levels correlated with active brain lesions. The ability of hydrocortisone to inhibit IL‐17 and IL‐22 production by MBP‐specific CD4⁺ T cells was inversely related to the number of active brain lesions. Finally, the production of both cytokines was significantly higher in cell cultures from Afrodescendant patients and it was less sensitive to hydrocortisone inhibition. In summary, our data suggest that IL‐17‐ and IL‐22‐secreting CD4⁺ T cells resistant to corticoids are associated with radiological activity of the MS in early stages of the disease, mainly among Afrodescendant patients who, normally, have worse prognosis.     

Histogram analysis of quantitative T1 and MT maps from ultrahigh field MRI in clinically isolated syndrome and relapsing–remitting multiple sclerosis

This study used quantitative MRI to study normal appearing white matter (NAWM) in patients with clinically isolated syndromes suggestive of multiple sclerosis and relapsing–remitting multiple sclerosis (RRMS). This was done at ultrahigh field (7 T) for greater spatial resolution and sensitivity. 17 CIS patients, 11 RRMS patients, and 20 age‐matched healthy controls were recruited. They were scanned using a 3D inversion recovery turbo field echo sequence to measure the longitudinal relaxation time (T₁). A 3D magnetization transfer prepared turbo field echo (MT‐TFE) sequence was also acquired, first without a presaturation pulse and then with the MT presaturation pulse applied at ?1.05 kHz and +1.05 kHz off resonance from water to produce two magnetization transfer ratio maps (MTR(?) and MTR(+)). Histogram analysis was performed on the signal from the voxels in the NAWM mask. The upper quartile cut‐off of the T₁ histogram was significantly higher in RRMS patients than in controls (p < 0.05), but there was no difference in CIS. In contrast, MTR was significantly different between CIS or RRMS patients and controls (p < 0.05) for most histogram measures considered. The difference between MTR(+) and MTR(?) signals showed that NOE contributions dominated the changes found. There was a weak negative correlation (r = ?0.46, p < 0.05) between the mode of T₁ distributions and healthy controls' age; this was not significant for MTR(+) (r = ?0.34, p > 0.05) or MTR(?) (r = 0.13, p > 0.05). There was no significant correlation between the median of T₁, MTR(?), or MTR(+) and the age of healthy controls. Furthermore, no significant correlation was observed between EDSS or disease duration and T₁, MTR(?), or MTR(+) for either CIS or RRMS patients. In conclusion, MTR was found to be more sensitive to early changes in MS disease than T₁. Copyright © 2015 John Wiley & Sons, Ltd.