A polymorphism in the promoter region of the CD86 (B7.2) gene is associated with systemic sclerosis

Impact of Single-Nucleotide Polymorphisms of CTLA-4, CD80 and CD86 on the Effectiveness of Abatacept in Patients with Rheumatoid Arthritis

Abatacept (ABA) is used as a first-line treatment in patients diagnosed with moderate and severe rheumatoid arthritis (RA). The interindividual response to ABA therapy is very variable in these patients. The objective of our study was therefore to investigate the role of polymorphisms of the CTLA-4, CD80 and CD86 genes, as well as that of clinical factors of the disease, in the response to ABA in patients with RA. A retrospective cohort study was carried out in 109 patients receiving treatment with ABA and diagnosed with RA. The genetic variables were analyzed using real-time PCR with TaqMan^® probes. The patients were classified according to the European League Against Rheumatism (EULAR) criteria at 6 and 12 months from start of treatment. The independent variables associated with higher EULAR response were lower duration of previous biologic disease-modifying anti-rheumatic drugs and lower baseline values of the disease activity score 28 after 6 months of ABA treatment; and lower baseline patient’s visual analogue scale (PVAS) after 12 months. In addition, a significant association was found between duration of ABA treatment, non-administration of concomitant glucocorticoids and lower baseline values of the number of inflamed joints and erythrocyte sedimentation rate clinical variables, with remission of the disease after 6 months’ treatment with ABA. Finally, remission of the disease after 12 months’ treatment with ABA was associated with earlier age at start of ABA therapy and lower number of previous biologic therapies (BTs). The CTLA-4rs5742909-T allele and the CTLA-4rs231775-G allele were found to be associated with satisfactory EULAR response and low disease activity (LDA) after 12 months’ treatment with ABA (CTLA-4rs5742909 T vs. CC; OR = 5.88; CI_95% = 1.48–23.29 and OR = 4.75; CI_95% = 1.35–17.94, respectively, and CTLA-4rs231775 G vs. AA, OR = 3.48; CI_95% = 1.20–10.09 and OR = 4.68; CI_95% = 1.49–17.94, respectively). In conclusion, patients with RA treated with ABA showed better EULAR response and LDA rate when they had the CTLA-4 rs5742909-T or CTLA-4 rs231775-G polymorphisms; furthermore, this remission rate increased in patients that began ABA treatment earlier, those with a lower number of previous BTs and those with a lower PVAS value.

Genetic association between cluster of differentiation 86 variations and sepsis risk: A case-control study

The aim of this study was to investigate the correlation between cluster of differentiation 86 (CD86) gene rs1129055 and rs2715267 single nucleotide polymorphisms and sepsis susceptibility.One hundred twenty-five sepsis patients and 120 healthy controls were enrolled in this case-control study. CD86 polymorphisms rs1129055 and rs2715267 were genotyped through polymerase chain reaction-restriction fragment length polymorphism approach. Chi-square test was used to analyze differences in genotype and allele frequencies of the 2 polymorphisms between case and control groups. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to present the association strength of the polymorphisms with sepsis susceptibility.AA genotype and A allele frequencies of CD86 rs1129055 were significantly lower in sepsis patients than in healthy controls (P < .05), revealing their significant associations with decreased disease susceptibility (OR = 0.351, 95% CI = 0.169-0.728; OR = 0.593, 95% CI = 0.415-0.847). Nevertheless, rs2715267 had no significant association with sepsis susceptibility (P > .05).AA genotype and A allele of CD86 polymorphism rs1129055 might be correlated with decreased sepsis susceptibility in Chinese Han population, but not rs2715267. Further study should be performed to verify our findings.

The Influence of Genetic Variations in the CD86 Gene on the Outcome after Allogeneic Hematopoietic Stem Cell Transplantation

CD86 molecule is the ligand for both costimulatory (CD28) and coinhibitory (CTLA-4) molecules, and it regulates immune response after allogeneic hematopoietic stem cell transplantation (alloHSCT). Therefore, we postulate that CD86 gene variations might influence the outcome after alloHSCT. Altogether, 295 adult patients (pts) undergoing related (105 pts) and unrelated (190 pts) donor-matched HSCT were genotyped for the following CD86 gene polymorphisms: rs1129055, rs9831894, and rs2715267. Moreover, the donors' rs1129055 polymorphism was determined. None of the investigated SNPs alone were associated with aGvHD and rate of relapse. However, we showed that rs2715267 SNP influenced overall survival (OS) after alloHSCT. The 24-month OS for the rs271526GG recipients was worse than that for the recipients possessing T allelle (TT or GT genotypes) (p = 0.009). Moreover, analysis of gene-gene interaction between CD86 and CTLA-4 showed that having both the A allele for CD86 rs1129055 and the CTLA-4 CT60GG genotype in recipients increased the risk of aGvHD about 3.5 times. Interestingly, the donors' rs1129055GG genotype and the recipients' CT60GG genotype also increased the risk of aGvHD about 2.7-fold. We postulate that recipients' CD86 gene polymorphisms influence the overall survival after alloHSCT and, together with CTLA-4 polymorphisms, might be considered a risk factor for aGvHD.

Danger signal-dependent activation of human dendritic cells by plasma-derived factor VIII products

Treatment of haemophilia A by infusions of the clotting factor VIII (FVIII) results in the development of inhibitors/anti-drug antibodies in up to 25 % of patients. Mechanisms leading to immunogenicity of FVIII products are not yet fully understood. Amongst other factors, danger signals as elicited upon infection or surgery have been proposed to play a role. In the present study, we focused on effects of danger signals on maturation and activation of dendritic cells (DC) in the context of FVIII application. Human monocyte-derived DC were treated with FVIII alone, with a danger signal alone or a combination of both. By testing more than 60 different healthy donors, we show that FVIII and the bacterial danger signal lipopolysaccharide synergise in increasing DC activation, as characterised by increased expression of co-stimulatory molecules and secretion of pro-inflammatory cytokines. The degree and frequency of this synergistic activation correlate with CD86 expression levels on immature DC prior to stimulation. In our assay system, plasma-derived but not recombinant FVIII products activate human DC in a danger signal-dependent manner. Further tested danger signals, such as R848 also induced DC activation in combination with FVIII, albeit not in every tested donor. In our hands, human DC but not human B cells or macrophages could be activated by FVIII in a danger signal-dependent manner. Our results suggest that immunogenicity of FVIII is a result of multiple factors including the presence of danger, predisposition of the patient, and the choice of a FVIII product for treatment.

CTLA4 and CD86 gene polymorphisms and susceptibility to chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) may be related to chronic inflammation and immune-mediated conditions, and its pathogenesis involves T-cell activation and proliferation. Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and costimulatory molecules (CD80/CD86) genes are important mediators of T-cell activation in the immune response. The aim of this study was to investigate whether +2379G/C (rs17281995) and +1057G/A (rs1129055) in CD86 and -318C/T (rs5742909) and +49A/G (rs231775) in CTLA-4 genes single nucleotide polymorphisms (SNPs) are associated with COPD in a Chinese population. The four polymorphisms were identified in 396 COPD patients and 400 controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The frequency of the T allele of the -318C/T in CTLA-4 and the A allele of the +1057G/A in CD86 polymorphisms showed significant association with COPD when compared with controls (T allele: p < 0.0001; A allele: p = 0.009). Comparison of genotype frequencies showed that -318CT, +1057GA, and +1057AA genotype was overrepresented in the COPD group, respectively (-318CT: 50.8% vs 28.5%, p < 0.0001; +1057GA: 58.6% vs 54.2%, p = 0.002; +1057AA: 30.1% vs 25.8%, p = 0.002). However, we failed to find any association between the four SNPs and COPD when cases were classified by smoking status or clinical stages (p > 0.05). The results indicate that the polymorphisms of CTLA-4 (-318C/T) and CD86 (+1057G/A) may be important genetic factor associated with risk or protection for COPD in Chinese population.

Identification of a major susceptibility locus for lethal graft-versus-host disease in MHC-matched mice

Graft-vs-host disease (GVHD) is the major cause of morbidity and mortality after allogeneic hemopoietic cell transplantation. From a genetic perspective, GVHD is a complex phenotypic trait. Although it is understood that susceptibility results from interacting polymorphisms of genes encoding histocompatibility Ags and immune regulatory molecules, a detailed and integrative understanding of the genetic background underlying GVHD remains lacking. To gain insight regarding these issues, we performed a forward genetic study. A MHC-matched mouse model was used in which irradiated recipient BALB.K and B10.BR mice demonstrate differential susceptibility to lethal GHVD when transplanted using AKR/J donors. Assessment of GVHD in (B10.BR x BALB.K)F(1) mice revealed that susceptibility is a dominant trait and conferred by deleterious alleles from the BALB.K strain. To identify the alleles responsible for GVHD susceptibility, a genome-scanning approach was taken using (B10.BR x BALB.K)F(1) x B10.BR backcross mice as recipients. A major susceptibility locus, termed the Gvh1 locus, was identified on chromosome 16 using linkage analysis (logarithm of the odds, 9.1). A second locus was found on chromosome 13, named Gvh2, which had additive but protective effects. Further identification of Gvh genes by positional cloning may yield new insight into genetic control mechanisms regulating GVHD and potentially reveal novel approaches for effective GVHD therapy.

Genetics and genomic studies in scleroderma (systemic sclerosis)

It currently is believed that scleroderma is a complex polygenic disease that occurs in genetically predisposed individuals who have encountered specific environment exposures and/or other stochastic factors. The nature of these genetic determinants and how they interact with environmental factors are areas of active investigation. This article discusses the evidence that supports a strong genetic link to scleroderma. These studies implicate potential pathogenetic mechanisms involved in scleroderma, which, it is hoped, may translate into clinical utility, including determination of disease risk, diagnosis, prognosis, and novel therapeutics.

Genetic basis for systemic sclerosis

Among the connective tissue diseases, systemic sclerosis is an orphan disease in which diffuse connective tissue alterations lead to multi-organ involvement. Environmental factors implicated in triggering this multifactorial disease include crystalline silica, chlorine solvents, welding vapors, and various other solvents. Clustering within families indicates a role for genetic factors. Although concordance for the disease among identical twins is low, concordance for autoantibodies associated with systemic sclerosis and for fibroblast gene expression profiles is higher. Because multiplex families are rare, association and candidate gene strategies are the most appropriate methods for investigating the genetics of systemic sclerosis. The most consistent data relate to the involvement of fibrosis genes, most notably the TGF-beta regulation pathway, secreted protein acid and rich in cysteine (SPARC) genes, and the fibrillin-1 gene (FBN1). Several variants of genes for cytokines or their receptors may be involved. Data on the vasculopathy characteristic of systemic sclerosis are somewhat conflicting. Investigations into the genetics of systemic sclerosis may shed light on the complex pathophysiology of this disease, help to identify factors that predict organ involvement, and suggest new treatment strategies.