Biomarker Commons

HLA polymorphism among Chinese patients with chronic plaque psoriasis: subgroup analysis.

Br J Dermatol. 2012 Feb;166(2):288-97

Authors: Chiu HY, Huang PY, Jee SH, Hu CY, Chou CT, Chang YT, Hwang CY, Tsai TF

Abstract
BACKGROUND: HLA-Cw*06 has a strong influence on the clinical features and the susceptibility to psoriasis in different ethnicities. It is also used as a biomarker to predict the therapeutic efficacy of biologics, with inconsistent results. Additionally, most Asian patients with psoriasis do not carry HLA-Cw*06.
OBJECTIVES: To determine additional HLA alleles which confer susceptibility or affect the severity of psoriasis in Chinese Han individuals. In addition, the potential of using HLA to predict treatment outcomes was also investigated.
METHODS: We conducted a case-control association study in 199 Chinese patients with psoriasis and 200 unrelated healthy controls. HLA-B and HLA-C genotyping was performed and correlated with the therapeutic efficacy of the biologics, including alefacept, efalizumab, etanercept and ustekinumab. Patients with psoriasis were divided into group A (high-need patients with moderate to severe psoriasis) and B (general patients with psoriasis).
RESULTS: The frequencies of HLA-B*60, HLA-B*75, HLA-Cw*06 and HLA-Cw*10 were significantly increased in patients with psoriasis compared with the healthy controls. However, the prevalence of HLA-Cw*06 was lower in group A compared with group B (6% vs. 17%, Pc=0·04). HLA-B*46 was found to be strongly associated with group A but not with group B patients with psoriasis. HLA-Cw*01/HLA-B*46 was also identified as a risk haplotype for Chinese patients with psoriasis, compatible with the results in Thais. Significant differences in response to biologics were observed between HLA-Cw*01+ and HLA-Cw*01- individuals in the alefacept treatment group, and between HLA-B*37+ and HLA-B*37-, and HLA-B*58+ and HLA-B*58- individuals in the efalizumab treatment group.
CONCLUSIONS: In addition to HLA-Cw*06, the HLA-Cw*01/HLA-B*46 haplotype was also increased in Chinese patients with psoriasis. High-need patients with psoriasis had a lower frequency of HLA-Cw*06 but a higher prevalence of HLA-B*46 compared with general patients with psoriasis in our population.

PMID: 21985130 [PubMed - indexed for MEDLINE]

Novel multiplex technology for diagnostic characterization of rheumatoid arthritis.

Arthritis Res Ther. 2011;13(3):R102

Authors: Chandra PE, Sokolove J, Hipp BG, Lindstrom TM, Elder JT, Reveille JD, Eberl H, Klause U, Robinson WH

Abstract
INTRODUCTION: The aim of this study was to develop a clinical-grade, automated, multiplex system for the differential diagnosis and molecular stratification of rheumatoid arthritis (RA).
METHODS: We profiled autoantibodies, cytokines, and bone-turnover products in sera from 120 patients with a diagnosis of RA of < 6 months' duration, as well as in sera from 27 patients with ankylosing spondylitis, 28 patients with psoriatic arthritis, and 25 healthy individuals. We used a commercial bead assay to measure cytokine levels and developed an array assay based on novel multiplex technology (Immunological Multi-Parameter Chip Technology) to evaluate autoantibody reactivities and bone-turnover markers. Data were analyzed by Significance Analysis of Microarrays and hierarchical clustering software.
RESULTS: We developed a highly reproducible, automated, multiplex biomarker assay that can reliably distinguish between RA patients and healthy individuals or patients with other inflammatory arthritides. Identification of distinct biomarker signatures enabled molecular stratification of early-stage RA into clinically relevant subtypes. In this initial study, multiplex measurement of a subset of the differentiating biomarkers provided high sensitivity and specificity in the diagnostic discrimination of RA: Use of 3 biomarkers yielded a sensitivity of 84.2% and a specificity of 93.8%, and use of 4 biomarkers a sensitivity of 59.2% and a specificity of 96.3%.
CONCLUSIONS: The multiplex biomarker assay described herein has the potential to diagnose RA with greater sensitivity and specificity than do current clinical tests. Its ability to stratify RA patients in an automated and reproducible manner paves the way for the development of assays that can guide RA therapy.

PMID: 21702928 [PubMed - indexed for MEDLINE]

Change in CD3 positive T-cell expression in psoriatic arthritis synovium correlates with change in DAS28 and magnetic resonance imaging synovitis scores following initiation of biologic therapy--a single centre, open-label study.

Arthritis Res Ther. 2011;13(1):R7

Authors: Pontifex EK, Gerlag DM, Gogarty M, Vinkenoog M, Gibbs A, Burgman I, Fearon U, Bresnihan B, Tak PP, Gibney RG, Veale DJ, FitzGerald O

Abstract
INTRODUCTION: With the development of increasing numbers of potential therapeutic agents in inflammatory disease comes the need for effective biomarkers to help screen for drug efficacy and optimal dosing regimens early in the clinical trial process. This need has been recognized by the Outcome Measures in Rheumatology Clinical Trials (OMERACT) group, which has established guidelines for biomarker validation. To seek a candidate synovial biomarker of treatment response in psoriatic arthritis (PsA), we determined whether changes in immunohistochemical markers of synovial inflammation correlate with changes in disease activity scores assessing 28 joints (ΔDAS28) or magnetic resonance imaging synovitis scores (ΔMRI) in patients with PsA treated with a biologic agent.
METHODS: Twenty-five consecutive patients with PsA underwent arthroscopic synovial biopsies and MRI scans of an inflamed knee joint at baseline and 12 weeks after starting treatment with either anakinra (first 10 patients) or etanercept (subsequent 15 patients) in two sequential studies of identical design. DAS28 scores were measured at both time points. Immunohistochemical staining for CD3, CD68 and Factor VIII (FVIII) was performed on synovial samples and scored by digital image analysis (DIA). MRI scans performed at baseline and at 12 weeks were scored for synovitis semi-quantitatively. The ΔDAS28 of the European League Against Rheumatism good response definition (>1.2) was chosen to divide patients into responder and non-responder groups. Differences between groups (Mann Whitney U test) and correlations between ΔDAS28 with change in immunohistochemical and MRI synovitis scores (Spearman's rho test) were calculated.
RESULTS: Paired synovial samples and MRI scans were available for 21 patients (8 anakinra, 13 etanercept) and 23 patients (8 anakinra, 15 etanercept) respectively. Change in CD3 (ΔCD3) and CD68 expression in the synovial sublining layer (ΔCD68sl) was significantly greater in the disease responders compared to non-responders following treatment (P = 0.005 and 0.013 respectively). ΔCD3, but not ΔCD68 or ΔFVIII, correlated with both ΔDAS28 (r = 0.49, P = 0.025) and ΔMRI (r = 0.58, P = 0.009).
CONCLUSIONS: The correlation of ΔCD3 with ΔDAS28 and ΔMRI following biologic treatment in this cohort contributes to the validation of ΔCD3 as a synovial biomarker of disease response in PsA, and supports the further evaluation of ΔCD3 for predictive properties of future clinical outcomes.

PMID: 21272347 [PubMed - indexed for MEDLINE]

Alcohol misuse in patients with psoriasis: identification and relationship to disease severity and psychological distress.

Br J Dermatol. 2011 Jun;164(6):1256-61

Authors: McAleer MA, Mason DL, Cunningham S, O'Shea SJ, McCormick PA, Stone C, Collins P, Rogers S, Kirby B

Abstract
BACKGROUND: Moderate to severe psoriasis is associated with increased alcohol intake and excessive mortality from alcohol-related causes. Alcohol biomarkers provide an objective measure of alcohol consumption. Carbohydrate-deficient transferrin (CDT) is the single most sensitive and specific alcohol biomarker.
OBJECTIVES: To assess alcohol consumption in a cohort of patients with moderate to severe psoriasis using standard alcohol screening questionnaires and biomarkers. We investigated whether there was an association between alcohol intake, anxiety, depression and disease severity.
METHODS: Consecutive patients with chronic plaque psoriasis were recruited and completed a range of anonymized assessments. Psoriasis severity, anxiety and depression, and the impact of psoriasis on quality of life were assessed. Alcohol screening questionnaires were administered. Blood specimens were taken and γ-glutamyltransferase (γGT) and CDT were measured.
RESULTS: A total of 135 patients completed the study. Using validated questionnaires, between 22% and 32% had difficulties with alcohol. Seven per cent had CDT > 1·6% indicating a heavy alcohol intake. The Alcohol Use Disorders Identification Test (AUDIT) questionnaire was superior to other validated questionnaires in detecting alcohol misuse. There were no significant associations between measures of excessive alcohol consumption and disease severity. Excessive alcohol intake as measured by the CAGE questionnaire was associated with increased depression (P = 0·001) but other measures of alcohol excess did not correlate with psychological distress. Men had significantly more difficulties with alcohol than women (P < 0·001).
CONCLUSION: Alcohol misuse is common in patients with moderate to severe psoriasis. Screening with the AUDIT questionnaire and CDT may allow the identification of patients who are misusing alcohol and allow appropriate intervention.

PMID: 21457207 [PubMed - indexed for MEDLINE]