Paediatric onset of multiple sclerosis: Analysis of chemokine and cytokine levels in the context of the early clinical course.

BACKGROUND: Inflammatory activity in children with paediatric onset multiple sclerosis (POMS) is higher than that in adults with MS. Chemokine/cytokine profiling in children may provide new insights into the disease pathogenesis and clinical course. The levels of chemokines/cytokines and their roles in POMS remain largely unknown. OBJECTIVE: To identify the possible utility of chemokines/cytokines in children with POMS, we analysed their levels at the time of disease diagnosis and in the context of subsequent clinical relapse. METHODS: CC and CXC motif ligand chemokines (CCL2, CXCL8, CXCL10, and CXCL13), interleukin (IL)-4, IL-17A, interferon gamma and B cell-activating factor in the blood and cerebrospinal fluid (CSF) of 34 POMS patients and 20 age-related controls were measured using Luminex multiplex bead and enzyme-linked immunosorbent assay techniques. Nonparametric tests were used for statistical analyses. RESULTS: The CSF levels of CXCL8 (p = 0.002), CXCL10 (p = 0.001), and CXCL13 (p<0.0001) were higher in POMS than in controls; CXCL10 and CXCL13 correlated with pleocytosis and oligoclonal bands. A subsequent clinical relapse occurred in 17/34 of the children; the median time from the diagnosis of POMS was 6 months (range, 2-64 months). The follow-up period of patients who did not experience a clinical relapse was significantly longer than the time to first relapse (p = 0.003). The initial CCL2 level was lower in relapsing than in non-relapsing patients (p = 0.063) and correlated negatively with the CSF/serum albumin ratio and positively with the time to relapse (p<0.04). CONCLUSIONS: Elevated CSF levels of CXL10 and CXCL13 in children with POMS at the time of disease diagnosis reflect inflammatory activity and suggest the involvement of adaptive immunity; elevated CXCL8 levels further indicate the involvement of innate immunity. An initial low CSF level of CCL2 may be associated with an unfavourable early MS course.

Enhanced STAT3 phosphorylation and PD-L1 expression in myeloid dendritic cells indicate impaired IL-27Ralpha signaling in type 1 diabetes.

Interleukin 27 (IL-27), a member of the IL-12 family, is important for T cell differentiation; however, little is known about its effect on dendritic cells (DCs). IL-27 can activate multiple signaling cascades, including the JAK/STAT pathway, and depending on the setting it can both promote and antagonize inflammatory responses. An anti-inflammatory function of IL-27 has been reported in several autoimmune diseases; however, in type 1 diabetes (T1D), an autoimmune disease where autoreactive cytotoxic T cells attack insulin-producing beta cells, IL-27 has been shown to have a dual role and contradictory effects. Here, we show impaired IL-27 signaling in a large cohort of T1D patients (n = 51) compared to age- and gender-matched healthy donors. Increased expression of the IL-27 receptor subunit IL-27Ralpha mRNA in purified myeloid DCs (mDCs), detected by gene expression microarrays was mirrored by enhanced signal transduction in T1D mDCs in response to IL-27 stimulation. Higher STAT phosphorylation in T1D patients was also accompanied by elevated expression of the inhibitory molecules PD-L1, PD-L2 and PD-1, which may suggest not only immunomodulatory mechanisms of IL-27 in T1D but also a compensatory effort of T1D dendritic cells against the ongoing inflammation.

A prospective study in children with a severe form of atopic dermatitis: clinical outcome in relation to cytokine gene polymorphisms.

BACKGROUND AND OBJECTIVE: The course of atopic dermatitis (AD) in childhood is characterized by typical changes in phenotype, including a shift from skin involvement to respiratory allergy usually around the third year of age. We thus designed a prospective study to monitor the outcome of severe AD and to investigate the association between cytokine gene polymorphisms and clinical manifestations. METHODS: Clinical and laboratory follow-up of 94 patients with severe AD and 103 healthy controls was performed using routine methodology. Allele, genotype, and haplotype frequencies of single nucleotide polymorphisms of 13 selected cytokine/receptor genes were analyzed using PCR with sequence-specific primers. RESULTS: In our study, genotypes of 7 polymorphisms--LL-4 -1098G/T and -590C/T, IL-6 -174C/G and nt565A/G, and IL-10 -1082A/G, -819C/T, and -592A/C were significantly associated with atopic AD (P < .05). A significant association was also found for TNF-alpha AA and IL-4 GC haplotypes and AD. We confirm the progressive clinical improvement of AD together with a decrease in the severity index SCORAD (SCORing atopic dermatitis) during childhood (P < .05). We found significant differences between IL-4Ralpha +1902 A/G and positivity of tree pollen-specific IgE (P < .05) in the AD group. Moreover, a weak association was also found between IL-10 -819C/T and IL-10 -590A/C and the appearance of allergic rhinitis (P < 0.1). CONCLUSIONS: We confirmed a clinical shift in allergic phenotype in the first 3 years of life, and showed an association between IL-4, IL-6, and IL-10 polymorphisms and AD. Our data indicate that IL-4alpha and IL-10 polymorphisms may be considered predictive factors of respiratory allergy in children with AD.

Selective increase in blood dendritic cell antigen-3-positive dendritic cells in bronchoalveolar lavage fluid in allergic patients.

Dendritic cells (DCs) are specific antigen-presenting cells that play critical roles in the initiation and polarization of immune responses. DCs residing in the lungs might be detected in the bronchoalveolar lavage fluid (BALF). We analysed DC compartment in the peripheral blood and BALF of patients with allergy and in controls. Plasmacytoid and four distinct subsets of myeloid DCs [characterized by the expression of blood dendritic cell antigen (BDCA)-1+ and -3+ and CD16 positivity or negativity] were detected in both tested compartments. We further evaluated the expression of C-type lectins [mannose receptor (MR), dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) and dendritic and epithelial cells (DEC)-205] relevant to the pathogenesis of asthma. Interestingly, we found a selective increase in the frequency of myeloid DC-expressing BDCA-3 and MR particularly in BALF from allergic patients. Specific and highly statistically significant increase in BDCA-3+ and/or MR+ DCs brings a novel characteristic to BAL analysis in allergic patients.

Serum immunoglobulin free light chains in severe forms of atopic dermatitis.

An increase in immunoglobulin free light chains (FLC) was recently described in several pathological conditions, including asthma. FLC pathology is classically associated with monoclonal gammopathies. Its association with allergic disorders is surprising and unexplained. We therefore tested a cohort of children with severe atopic dermatitis (SCORAD 50-80) to determine the serum levels of free kappa and lambda chains, and correlated the results with clinical status and relevant laboratory markers. Seventy-three patients with severe forms of AD, all children from 3 months to 3 years of age and ninety healthy age-matched controls were included in the study. Light chains in sera were tested using the Freelite assay (Binding Site, Birmingham, UK). There were highly significant differences in both kappa (mean: 7.05 and 3.22 mg/l) and lambda (mean: 10.99 and 9.8 mg/l) serum levels between patients and controls, respectively (P < 0.0001). The kappa/lambda ratio in patients with allergy (mean: 0.64) was significantly higher than in controls (0.33) (P < 0.0001). We further observed significantly increased levels of FLC and their ratio in the group of patients with severe forms of AD in comparison to the group of patients with a resting stage of the disease or healthy controls (P < 0.05 and P < 0.0001, respectively). On the other hand, we could not confirm any association of FLC levels with age or total IgE levels. In conclusion, an increase in FLC reflects disease activity in children with severe atopic dermatitis. FLC might thus represent an additional diagnostic marker independent of total IgE levels.