A single-nucleotide polymorphism marker within theFCRL5gene andHLA-B27positive Han Chinese ankylosing spondylitis patients

The rs6427384 and rs6692977 Single Nucleotide Polymorphisms of the Fc Receptor-Like 5 (FCRL5) Gene and the Risk of Ankylosing Spondylitis: A Case Control Study in a Single Center in China

BACKGROUND The study aimed to explore the genetic association of Fc receptor-like 5 (FCRL5) gene variants (rs6427384 and rs6692977) with ankylosing spondylitis risk in Chinese Han population. MATERIAL AND METHODS Genotyping for FCRL5 gene variations rs6427384 and rs6692977 was implemented among 130 ankylosing spondylitis cases and 135 healthy persons, through polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method. Frequency dissimilarity for 2 polymorphisms was compared between 2 groups using chi-square test. The association strength of FCRL5 gene polymorphism with ankylosing spondylitis risk was estimated by odds ratios with 95% confidence intervals. RESULTS The frequencies of rs6427384 CC genotype and C allele were significantly lower in the case group than that in the control group (P<0.05), which suggested that C allele of rs6427384 polymorphism might offer protection against ankylosing spondylitis onset. Whereas only 2 genotypes of rs6692977 were detected in the control group, and no significant association was found with ankylosing spondylitis susceptibility. CONCLUSIONS FCRL5 gene polymorphism rs6427384 was correlated to ankylosing spondylitis occurrence among Chinese Han population, while rs6692977 was not.

Genetic risk of FCRL3 and FCRL5 polymorphisms in children with asthma and allergic rhinitis in a Chinese Han population

OBJECTIVES

Asthma and allergic rhinitis (AR) frequently occur as comorbid diseases of the upper airways. Single-nucleotide polymorphisms (SNPs) in the FCRL3 and FCRL5 genes have recently been shown to be associated with various immune-related disorders. This study evaluated the association of FCRL3 and FCRL5 polymorphisms with asthma and allergic rhinitis (AR) in a Han Chinese population.

METHODS

Seven single nucleotide polymorphisms (SNPs) of the FCRL3 and FCRL5 were genotyped in 300 asthmatic children, and 206 healthy unrelated individuals using PCR-restriction fragment length polymorphism (PCR-RFLP) assay. Genotyping was validated by direct sequencing.

RESULTS

Our results showed that the frequencies of the rs6692977 CT genotype and T allele within FCRL5 were significantly higher in asthma with comorbid AR compared to healthy controls (Bonferroni-corrected p (Pc) = 3.75 × 10^-6; Pc = 0.006, respectively), whereas these of the CC genotype and C allele were significantly lower (Pc = 4.15 × 10^-5; Pc = 0.006, respectively). The frequencies of the rs7528684 A allele (Pc = 1.80 × 10^-3) and the rs10489678 G allele (Pc = 0.04) within FCRL3 were higher in asthma with comorbid AR than in controls. However, no differences in the tested genetic polymorphisms were detected between asthma and healthy individuals.

CONCLUSION

This study identified novel SNPs in FCRL3 and FCRL5 significantly associated with the risk for asthma with comorbid AR in the Chinese population. The genetic variants may play role in the development of the asthma phenotype in children with asthma.

Human FcR polymorphism and disease

Fc receptors play a central role in maintaining the homeostatic balance in the immune system. Our knowledge of the structure and function of these receptors and their naturally occurring polymorphisms, including single nucleotide polymorphisms and/or copy number variations, continues to expand. Through studies of their impact on human biology and clinical phenotype, the contributions of these variants to the pathogenesis, progression, and/or treatment outcome of many diseases that involve immunoglobulin have become evident. They affect susceptibility to bacterial and viral pathogens, constitute as risk factors for IgG or IgE mediated inflammatory diseases, and impact the development of many autoimmune conditions. In this chapter, we will provide an overview of these genetic variations in classical FcγRs, FcRLs, and other Fc receptors, as well as challenges in achieving an accurate and comprehensive understanding of the FcR polymorphisms and genomic architecture.

Detection of gene expression signatures related to underlying disease and treatment in rheumatoid arthritis patients

OBJECTIVES

Gene expression signatures can provide an unbiased view into the molecular changes underlying biologically and medically interesting phenotypes. We therefore initiated this study to identify signatures that would be of utility in studying rheumatoid arthritis (RA).

METHODS

We used microarray profiling of peripheral blood mononuclear cells (PBMCs) in 30 RA patients to assess the effect of different biologic agent (biologics) treatments and to quantify the degree of a type-I interferon (IFN) signature in these patients. A numeric score was derived for the quantification step and applied to patients with RA. To further characterize the IFN response in our cohort, we employed type-I IFN treatment of PBMCs in vitro and in reporter assays.

RESULTS

Profiling identified a subset of RA patients with upregulation of type-I IFN-regulated transcripts, thereby corroborating previous reports showing RA to be heterogeneous for an IFN component. A comparison of individuals currently untreated with a biologic with those treated with infliximab, tocilizumab, or abatacept suggested that each biologic induces a specific gene signature in PBMCs.

CONCLUSIONS

It is possible to observe signs of type-I IFN pathway activation in a subset of clinically active RA patients without C-reactive protein elevation. Furthermore, biologics-specific gene signatures in patients with RA indicate that looking for a biologic-specific response pattern may be a potential future tool for predicting individual patient response.

TH17, TH22 and Treg cells are enriched in the healthy human cecum

There is increasing evidence that dysregulation of CD4(+) T cell populations leads to intestinal inflammation, but the regional distribution of these populations throughout the intestinal tract in healthy individuals remains unclear. Here, we show that T(H)17, T(H)22 and T(Reg) cells are enriched in the healthy human cecum compared to the terminal ileum and sigmoid colon, whereas T(H)1 and T(H)2 cells do not significantly vary by location. Transcriptional profiling analysis of paired pinch biopsies from different regions of the intestine identified significant differences in the metabolic state of the terminal ileum, cecum, and sigmoid colon. An increased proportion of T(H)17 cells was positively associated with expression of resistin (RETN) and negatively associated with expression of trefoil factor 1 (TFF1). These results suggest that CD4(+) T helper cells that are important in maintaining mucosal barrier function may be enriched in the cecum as a result of metabolic differences of the surrounding microenvironment.

Association of FCRL4 polymorphisms on disease susceptibility and severity of ankylosing spondylitis in Chinese Han population

Previous studies have found that the Fc receptor-like (FCRL) molecule, involved in controlling B cell signaling, may contribute to the autoimmune disease process. Many studies have reported the relation of FCRL gene family with SLE and RA. We hypothesized that FCRL4 may be a key gene for ankylosing spondylitis (AS) development. To test this hypothesis, we screened FCRL4 polymorphisms in the Chinese Han population. Five tag single nucleotide polymorphisms (SNPs), including rs14335, rs849826, rs10489674, rs2778003, and rs2777963, were selected. Using a case-control study, five tag SNPs, which captured the majority of known common variation within FCRL4 gene, were selected and genotyped by Multiplex Snapshot technique. We analyzed 299 patients and 300 controls from China. The genotype analysis demonstrated that one of the FCRL4 tag SNPs rs2777963 TT genotype may be a risk factor of AS (χ(2) = 7.374, p = 0.024). The haplotype analysis indicated that there were no significant differences between AS cases and controls. Patients with AS who had rs14335 AA genotype had a significantly declined visual analogue scale patient's global assessment scores compared to those with the GG genotype (31.21 ± 26.25 vs 40.54 ± 25.40, p = 0.035) and GA genotype (38.29 ± 24.94 vs 40.54 ± 25.40, p = 0.044), and in locus rs10489674, TT genotype had significantly increased Bath Ankylosing Spondylitis Disease Activity Index scores compared to those with the CC genotype (4.73 ± 2.43 vs 3.15 ± 1.61, p = 0.003) and CT genotype (4.73 ± 2.43 vs 2.97 ± 1.71, p = 0.001). The FCRL4 polymorphisms may play an important role in the susceptibility and severity of AS in the Chinese Han population.