Large intra-individual variability of plasma cytokines in healthy young men: a two 24-h study over a month

Cytokine levels in blood are not yet fully considered as biomarkers for disease even if some significant progresses have been made in linking certain cytokines to some diseases. The aim of this study was to look for the stability of some cytokines in blood collected in two different days separated by one month. Fifteen healthy young men aged 20–30 years were selected for this study. Each subject participated in two 24-h sessions spaced a month apart. Blood sample was taken at 11:00, 17:00, 22:00, 01:00, 04:00, 06:00, and 08:00. Concentrations of interleukin-6, interleukin-1-receptor antagonist, soluble IL-2 receptor, interleukin-1 beta, and interleukin-2 were measured in serum. The circadian pattern of each variable was compared between the two days. The results show that there is no reliability for the measured cytokines. This study shows that cytokine levels measured in blood are neither reliable variables nor considered as stable markers in healthy subjects.     

Association between interleukin 4 gene intron 3 VNTR polymorphism and recurrent aphthous stomatitis in a cohort of Turkish patients

Objective

Recurrent aphthous stomatitis (RAS) is one of the most common oral mucosal diseases, with a multifactorial etiopathogenesis, an interaction between predisposing factors and/or systemic conditions and immunological components in genetically predisposed subjects. Although there is no clear genetic mode of inheritance, there is evidence that inheritance of specific gene polymorphisms may predispose individuals to RAS. The purpose of the present study was to investigate a possible association between the functional interleukin 4 (IL4) VNTR genetic polymorphism and RAS in a sample of Turkish patients.

Methods

The study included 145 unrelated patients with a clinical diagnosis of RAS and 150 unrelated healthy controls. Genomic DNA was isolated and IL4 gene 70 bp VNTR polymorphism determined by using polymerase chain reaction (PCR) with specific primers.

Results

The distribution of genotype and allele frequencies of IL4 gene intron 3 VNTR polymorphism was statistically different between RAS patients and control group (p < 0.0001 and p < 0.0001, respectively) P2P2 genotype and P2 allele were also found to be protective with a lower risk for susceptibility to RAS (p < 0.0001).

Conclusion

The results of this study suggest that intron 3 VNTR polymorphism in the IL4 gene is associated with RAS susceptibility in Turkish population.     

Association of BANK1 and cytokine gene polymorphisms with type 1 diabetes in Tunisia

Type 1 diabetes (T1D) is an autoimmune disease (AID) with both genetic and environmental components. We aimed to investigate the genetic association of polymorphisms in genes previously linked with other AIDs, namely BANK1, IL15 and IL2/IL21 region.     

Sphingolipids in apoptosis, survival and regeneration in the nervous system

Simple sphingolipids such as ceramide, sphingosine and sphingosine 1-phosphate are key regulators of diverse cellular functions. Their roles in the nervous system are supported by extensive evidence derived primarily from studies in cultured cells. More recently animal studies and studies with human samples have revealed the importance of ceramide and its metabolites in the development and progression of neurodegenerative disorders. The roles of sphingolipids in neurons and glial cells are complex, cell dependent, and many times contradictory. In this review I will summarize the effects elicited by ceramide and ceramide metabolites in cells of the nervous system, in particular those effects related to cell survival and death, emphasizing the molecular mechanisms involved. I also discuss recent evidence for the implication of sphingolipids in the development and progression of certain dementias.     

Lineage tree analysis of immunoglobulin variable-region gene mutations in autoimmune diseases: chronic activation, normal selection

Autoimmune diseases show high diversity in the affected organs, clinical manifestations and disease dynamics. Yet they all share common features, such as the ectopic germinal centers found in many affected tissues. Lineage trees depict the diversification, via somatic hypermutation (SHM), of immunoglobulin variable-region (IGV) genes. We previously developed an algorithm for quantifying the graphical properties of IGV gene lineage trees, allowing evaluation of the dynamical interplay between SHM and antigen-driven selection in different lymphoid tissues, species, and disease situations. Here, we apply this method to ectopic GC B cell clones from patients with Myasthenia Gravis, Rheumatoid Arthritis, and Sj?gren's Syndrome, using data scaling to minimize the effects of the large variability due to methodological differences between groups. Autoimmune trees were found to be significantly larger relative to normal controls. In contrast, comparison of the measurements for tree branching indicated that similar selection pressure operates on autoimmune and normal control clones.     

脉冲磁场对白血病细胞HL60/ADR多药耐药的逆转效果及分子机制研究

目的:探讨脉冲磁场(pulsedmagnetic fields,PMF)对白血病细胞HL60/ADR多药耐药的逆转效果及其可能的分子机制.方法:生长曲线法检测PMF的细胞毒性;MTT法测定HL60、HL60/ADR的IC50及经不同参数PMF作用后HL60/ADR的IC50,计算耐药倍数和逆转倍数;流式细胞术检测PMF作用前后HL60/ADR细胞内药物蓄积变化及多药耐药相关蛋白(Multidrug Rcsistance Related Protcinl MRPI)阳性表达率的变化;RT-PCR法检测MRPI基因表达的变化.结果:单独PMF对HL60/ADR细胞的生长没有明显抑制作用,不同参数(频率为150Hz和250Hz,场强均为40mT,照射时间30min和1 h)的PMF均能有效逆转HL60/ADR的多药耐药,150 Hz/1 h作用最为明显,逆转倍数为5.891倍.PMF作用后Rh123在HL60/ADR细胞内的蓄积增加了近8.0%,而MRPl基因表达下调了68.3%,蛋白阳性表达率下调23.6%.结论:PMF能够通过下调MRPl基因和蛋白的表达.进而增加Rh123在细胞内的蓄积,功能性部分逆转白血病细胞的多药耐药.     

Vitronectin promotes oligodendrocyte differentiation during neurogenesis of human embryonic stem cells

We demonstrate enhanced differentiation of oligodendrocytes during neurogenesis of human embryonic stem cells (hESCs) using an extracellular matrix protein, vitronectin (VN). We show that VN is expressed in the ventral part of the developing human spinal cord. Combined treatment of retinoic acid, sonic hedgehog, and noggin in the presence of VN allows hESCs to differentiate into O4-positive oligodendrocytes. Particularly, VN profoundly promotes the derivation of oligodendrocyte progenitors that proliferate and differentiate into oligodendrocytes in response to mitogenic and survival factors. These results support the beneficial effect of VN on oligodendrocytic differentiation of hESCs.     

FGF signaling via MAPK is required early and improves Activin A-induced definitive endoderm formation from human embryonic stem cells

Considering their unlimited proliferation and pluripotency properties, human embryonic stem cells (hESCs) constitute a promising resource applicable for cell replacement therapy. To facilitate this clinical translation, it is critical to study and understand the early stage of hESCs differentiation wherein germ layers are defined. In this study, we examined the role of FGF signaling in Activin A-induced definitive endoderm (DE) differentiation in the absence of supplemented animal serum. We found that activated FGF/MAPK signaling is required at the early time point of Activin A-induced DE formation. In addition, FGF activation increased the number of DE cells compared to Activin A alone. These DE cells could further differentiate into PDX1 and NKX6.1 positive pancreatic progenitors in vitro. We conclude that Activin A combined with FGF/MAPK signaling efficiently induce DE cells in the absence of serum. These findings improve our understanding of human endoderm formation, and constitute a step forward in the generation of clinical grade hESCs progenies for cell therapy.