Displaying publications 1 - 20 of 21 in total

Abstract:
Sort:
  1. Too CL, Murad S, Hansson M, Alm LM, Dhaliwal JS, Holmdahl R, et al.
    Arthritis Rheumatol, 2017 01;69(1):58-69.
    PMID: 27483449 DOI: 10.1002/art.39827
    OBJECTIVE: Antibodies to the citrullinated protein antigens (ACPAs) are important in the diagnosis and pathogenesis of rheumatoid arthritis (RA). However, the prevalence of ACPAs with different fine specificities in different populations is unclear. This study sought to examine the fine specificity of the antibody responses toward citrullinated proteins in RA patients from Malaysia, an area where genetic and environmental determinants of RA are different from those in more frequently studied cohorts of Caucasian subjects.

    METHODS: A multiplex analytic microarray system was used to analyze the occurrence of antibodies to 10 different citrullinated peptides (filaggrin [fil307-324], vimentin [Vim2-17, Vim60-75], fibrinogen [Fibα563-583, Fibα580-600, Fibβ36-52, Fibβ62-81a, Fibβ62-81b], enolase [Eno5-21], and type II collagen [CitCII355-378]) in serum samples from 4,089 RA patients (1,231 Malaysian and 2,858 Swedish) and 827 healthy control subjects (249 Malaysian and 578 Swedish). The positive reaction threshold for each peptide was set separately for each population based on a specificity of 98%.

    RESULTS: Distinct differences in the frequencies of 5 ACPA fine specificities (Vim60-75, Vim2-17, Fibβ62-81b, Eno5-21, and CitCII355-378) were found between the Malaysian and Swedish RA populations, despite a nearly identical percentage of patients in each population who were positive for anti-cyclic citrullinated peptide 2 antibodies. In Malaysian RA patients compared with Swedish RA patients, the frequencies of antibodies to Vim60-75 (54% versus 44%, corrected P [Pcorr ] = 1.06 × 10-8 ) and CitCII355-378 (17% versus 13%, Pcorr  = 0.02) were significantly higher, while the frequencies of antibodies to Vim2-17 (25% versus 32%, Pcorr  = 1.91 × 10-4 ), Fibβ62-81b (15% versus 30%, Pcorr  = 2.47 × 10-22 ), and Eno5-21 (23% versus 50%, Pcorr  = 3.64 × 10-57 ) were significantly lower.

    CONCLUSION: Serum ACPA fine specificities differ between RA patients in different populations, although the total proportions of individuals positive for ACPAs are similar. Differing patterns of ACPA fine specificity could be attributed to variations in genetic and/or environmental factors.

    Matched MeSH terms: Arthritis, Rheumatoid/immunology*
  2. Othman MA, Ghazali WSW, Hamid WZWA, Wong KK, Yahya NK
    Saudi Med J, 2017 Sep;38(9):934-941.
    PMID: 28889152 DOI: 10.15537/smj.2017.9.20841
    OBJECTIVES: To evaluate levels of anti-carbamylated protein (anti-CarP) antibodies in rheumatoid arthritis (RA) patients and to determine their association with serological parameters and disease activity. Methods: A cross-sectional study involving 105 multiethnic RA patients (48 rheumatoid factor [RF]-positive and 57 RF-negative patients) was conducted at Hospital Universiti Sains Malaysia, Kelantan, Malaysia, from January 2015 to February 2016. Fifty healthy controls (HCs) were included. C-reactive protein (CRP), RF, anti-cyclic citrullinated peptide (anti-CCP) and anti-CarP antibodies were measured. A health assessment questionnaire (HAQ) was administered to the study participants and 28-joint Disease Activity Score (DAS28) were obtained. Results: The level of anti-CarP antibodies was significantly increased in the RA patients compared with HCs (p=0.042). The presence of anti-CarP antibodies was significantly associated with RF (p=0.019) and the HAQ (p=0.010). A significant association between the presence of anti-CarP antibodies and the DAS28 was not found (p=0.632). Conclusion: Our study provides further evidence that the level of anti-CarP antibodies is significantly elevated in RA patients.

    Study site: Rheumatology clinic, Hospital Universiti Sains Malaysia
    Matched MeSH terms: Arthritis, Rheumatoid/immunology*
  3. Yahya A, Bengtsson C, Larsson P, Too CL, Mustafa AN, Abdullah NA, et al.
    Mod Rheumatol, 2014 Mar;24(2):271-4.
    PMID: 24593203 DOI: 10.3109/14397595.2013.854076
    OBJECTIVES: Silica exposure has been associated with an increased risk of developing rheumatoid arthritis (RA), especially among smokers. In this study, we aimed at examining the association between silica exposure (and its interaction with smoking) and the risk of RA in the Malaysian population.
    METHODS: In total, 149 cases and 213 matched controls, all men, were included between August 2005 and December 2009. A case was defined as a person with early diagnosed RA using the 1987 American College of Rheumatology criteria for RA. Controls were randomly selected matched on sex, age and residential area. Silica exposure was defined as exposure to stone dust, rock drilling or stone crushing, and smoking status was categorized as ever/never cigarette smoking.
    RESULTS: An increased risk of anti-citrullinated protein antibody (ACPA)-positive RA (OR = 2.4, 95 % CI 1.0-5.6) was observed among those exposed to silica. Ever-smokers exposed to silica had a particularly high risk of developing ACPA-positive RA (OR = 7.5, 95 % CI 2.3-24.2), compared with never-smokers not exposed to silica. No association was found regarding ACPA-negative RA.
    CONCLUSION: Our data demonstrate that exposure to both silica and cigarette smoke comprise risks for developing RA in the Malaysian genetic context. The findings expand a link between environmental lung exposures and ACPA-positive RA to Asian populations.
    Matched MeSH terms: Arthritis, Rheumatoid/immunology
  4. Tsuru T, Terao K, Murakami M, Matsutani T, Suzaki M, Amamoto T, et al.
    Mod Rheumatol, 2014 May;24(3):511-6.
    PMID: 24252023 DOI: 10.3109/14397595.2013.843743
    To evaluate humoral immune response to influenza vaccine and polysaccharide pneumococcal vaccine in patients with rheumatoid arthritis (RA) or Castleman's disease (CD) during tocilizumab therapy.
    Matched MeSH terms: Arthritis, Rheumatoid/immunology
  5. Gomez EL, Gun SC, Somanath SD, Chinna K, Radhakrishnan AK
    Mod Rheumatol, 2013 Jul;23(4):716-21.
    PMID: 22854883 DOI: 10.1007/s10165-012-0718-6
    OBJECTIVES: The prognostic significance of rheumatoid factor (RF) and anticyclic citrullinated peptide antibody (anti-CCP) in rheumatoid arthritis (RA) remains contentious due to the conflicting lines of evidence. This study aims to determine the association between RF isotypes and anti-CCP with disease severity in RA patients from three ethnic groups.
    METHODS: A total of 147 RA patients from three different ethnic groups (Malays, Chinese, and Indians) who fulfilled the 1987 American College of Rheumatology (ACR) revised criteria for RA were recruited into this study. The seroprevalence of RF isotypes immunoglobulin (Ig)A, IgG, and IgM, as well as anti-CCP was determined using commercial enzyme-linked immunosorbent assay (ELISA) kits. Multinomial regression analysis was performed to assess the independent effects of autoantibody status on the development of deforming and erosive RA and the presence of extra-articular manifestations (EAM).
    RESULTS: In Chinese patients, we found a significant association (p < 0.05) between IgG RF and anti-CCP and the presence of erosive disease, as well as IgM RF and IgG RF with the presence of joint deformities. In Indian patients, IgM RF was associated with deforming disease, whereas none of the antibodies were associated with disease severity in Malay patients. Multinomial regression analysis revealed that IgG RF was the most important predictor variable for erosive disease in Chinese patients, and IgM RF the only predictor variable associated with deforming disease in both Chinese and Indian RA patients.
    CONCLUSIONS: There is variability in the phenotypic association of RF isotypes and anti-CCP in relation to disease severity of RA in the three ethnic groups. RF, in particular, IgG and IgM, may be better prognosticators of severe disease in Chinese and Indian patients.
    Matched MeSH terms: Arthritis, Rheumatoid/immunology*
  6. Yahya A, Bengtsson C, Lai TC, Larsson PT, Mustafa AN, Abdullah NA, et al.
    Mod Rheumatol, 2012 Aug;22(4):524-31.
    PMID: 22006120 DOI: 10.1007/s10165-011-0544-2
    We investigated the association between cigarette smoking and the risk of developing rheumatoid arthritis (RA) in the Malaysian population. A total of 1,056 RA patients and 1,416 matched controls aged 18-70 years within a defined area of Peninsular Malaysia were evaluated in a case-control study between August 2005 and December 2009. A case was defined as a person with early diagnosed RA using the 1987 American College of Rheumatology criteria for RA. Controls were randomly selected matched for sex, age, and residential area. Cases and controls answered a questionnaire on a broad range of issues, including lifestyle factors and smoking habits wherein current and former smoking was classified as ever-smoking. The presence of anti-citrullinated peptide antibodies (ACPA) was determined for cases and controls. We found that ever-smokers had an increased risk of developing ACPA-positive RA [odds ratio (OR) = 4.1, 95% confidence interval (CI) 1.9-9.2] but not ACPA-negative RA (OR = 0.7, 95% CI 0.3-2.0), compared with never-smokers. A significant dose-response relationship between cumulative dose of smoking and risk of ACPA-positive RA was observed (<20 pack-years OR = 3.3, 95% CI 1.1-9.8; at least 20 pack-years OR = 5.2, 95% CI 1.6-17.6). Hence, smoking is associated with an increased risk of ACPA-positive RA in the Malaysian population, in which the genetic context is similar to several other Asian countries.
    Matched MeSH terms: Arthritis, Rheumatoid/immunology
  7. Pavai S, Sargunan S, Zain AA, Chow SK
    Malays J Pathol, 2011 Dec;33(2):101-6.
    PMID: 22299210 MyJurnal
    Aim: Autoantibodies against cyclic citrullinated peptide (anti-CCP) are considered to be a sensitive and specific marker for rheumatoid arthritis (RA). This study evaluated the diagnostic and analytical performances of the automated anti-CCP assay.
    Materials and Method: Sera from 80 patients with established RA, 65 from other rheumatic diseases (non-RA) and 55 from healthy controls were studied using second generation anti-CCP. Rheumatoid factor (RF) was also assayed in each sample, and the results were compared to the anti-CCP fi ndings. Serum pools were used to determine the precision and linearity.
    Results: At a cut-off of 7.4 U/ml for anti-CCP, the sensitivity and specificity for RA were 65% and 98% respectively. RF had a sensitivity of 58% and a lower specifi city of 93 % than anti-CCP. Conclusion: The high specificity of the assay suggests that anti-CCP is useful in the diagnosis of rheumatoid arthritis and in our cohort of study population anti-CCP exhibits a better diagnostic value than RF. A considerable proportion (28%) of RF-negative RA patients were anti-CCP positive. Based on analytical performance of the assay, we conclude that full automation and high throughput features of AxSYM makes it an ideal platform for routine testing of anti-CCP.
    Study site: Rheumatology clinic, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia
    Matched MeSH terms: Arthritis, Rheumatoid/immunology
  8. Yusof Z, Porter SR, Greenman J, Scully C
    J Nihon Univ Sch Dent, 1995 Dec;37(4):197-200.
    PMID: 8820338
    Levels of serum IgG against Porphyromonas gingivalis cell sonicate were determined in patients with rheumatoid arthritis (RA) (n = 25), rapidly progressive periodontitis (RPP)(n = 25) and adult periodontitis (AP)(n = 15) and controls (HP)(n = 10) utilizing the ELISA technique. Comparison between groups showed no significant differences between the HP and RA groups and also between the RPP and AP groups. The increased levels of IgG in the RPP and AP groups were comparable. Significant differences in IgG levels were noted between HP and RPP (p<0.05) and between HP and AP (p<0.01). The differences between RA and RPP and between RA and AP were highly significant (p<0.0001). Thus it was revealed that the serum levels of IgG against P. gingivalis in RPP and AP patients were elevated, whereas the levels in RA patients were comparable to those in controls.
    Matched MeSH terms: Arthritis, Rheumatoid/immunology
  9. Sulaiman FN, Wong KK, Ahmad WAW, Ghazali WSW
    Medicine (Baltimore), 2019 Mar;98(12):e14945.
    PMID: 30896663 DOI: 10.1097/MD.0000000000014945
    Rheumatoid arthritis (RA) is a chronic debilitating inflammatory disease affecting mainly the joint, surrounding tissue and other extra-articular structures in the body. RA can lead to destruction of bone and cartilage which may cause severe disability and it is characterized by the presence of serum rheumatoid factor (RF). The anti-cyclic citrullinate peptide (anti-CCP) antibody is another serum biomarker used in RA diagnosis with higher sensitivity and specificity.In this cross-sectional study with retrospective record review, 159 established RA patients from Hospital Universiti Sains Malaysia (HUSM) were recruited. Enzyme-linked immunosorbent assays (ELISAs) for serum RF and anti-CCP were performed. Our goal was to evaluate the significance of anti-CCP antibody in predicting the disease activity and progression in terms of radiological and extra-articular manifestations upon diagnosis.Of the 159 RA patients included in this study, mean age was 48.3 years old and majority (n = 134; 84.3%) were female. A total of 83 (52.2%) and 99 (62.3%) patients had anti-CCP antibody and RF, respectively. Mean Disease Activity Score-28 for Rheumatoid Arthritis with erythrocyte sedimentation rate (ESR) (DAS28-ESR) score for all patients was 4.74 (medium and high disease activity). Fifty-eight (36.5%) patients had radiological defects and 49 (30.8%) patients had extra-articular involvement manifested by rheumatoid nodule, pulmonary involvement, and anemia.In terms of anti-CCP antibody association with clinical and laboratory parameters, a significant co-occurrence of RF and anti-CCP antibody (P = .002) was observed. Anti-CCP antibody was significantly associated with radiological defects in which majority of patients with such defects (n = 40/58; 68.9%) were positive for anti-CCP antibody (P = .001). However, there was no significant difference between mean and classes of disease activity score and extra-articular manifestations between different anti-CCP antibody groups. In addition, extra-articular manifestations were not associated with high disease activity upon RA diagnosisThere was a significant association between anti-CCP antibody positivity and positive RF. Radiological defects were the sole clinical parameter significantly associated with anti-CCP antibody positivity, indicating that patients positive for anti-CCP antibody should be routinely monitored for radiological defects and their onset.
    Matched MeSH terms: Arthritis, Rheumatoid/immunology
  10. Too CL, Yahya A, Murad S, Dhaliwal JS, Larsson PT, Muhamad NA, et al.
    Arthritis Res Ther, 2012;14(2):R89.
    PMID: 22537824 DOI: 10.1186/ar3813
    INTRODUCTION:Rheumatoid arthritis (RA) is a multifactorial autoimmune disease in which genetic and environmental factors interact in the etiology. In this study, we investigated whether smoking and HLA-DRB1 shared-epitope (SE) alleles interact differently in the development of the two major subgroups of rheumatoid arthritis (RA), anti-citrullinated proteins antibody (ACPA)-positive and ACPA-negative disease, in a multiethnic population of Asian descent.
    METHODS: A case-control study comprising early diagnosed RA cases was carried out in Malaysia between 2005 and 2009. In total, 1,076 cases and 1,612 matched controls participated in the study. High-resolution HLA-DRB1 genotyping was performed for shared-epitope (SE) alleles. All participants answered a questionnaire on a broad range of issues, including smoking habits. The odds ratio (OR) of developing ACPA-positive and ACPA-negative disease was calculated for smoking and the presence of any SE alleles separately. Potential interaction between smoking history (defined as "ever" and "never" smoking) and HLA-DRB1 SE alleles also was calculated.
    RESULTS: In our multiethnic study, both the SE alleles and smoking were associated with an increased risk of developing ACPA-positive RA (OR SE alleles, 4.7; 95% confidence interval (CI), 3.6 to 6.2; OR smoking, 4.1; 95% CI, 1.9 to 9.2). SE-positive smokers had an odds ratio of ACPA-positive RA of 25.6 (95% CI, 10.4 to 63.4), compared with SE-negative never-smokers. The interaction between smoking and SE alleles was significant (attributable proportion due to interaction (AP) was 0.7 (95% CI, 0.5 to 1.0)). The HLA-DRB1*04:05 SE allele, which is common in Asian populations, but not among Caucasians, was associated with an increased risk of ACPA-positive RA, and this allele also showed signs of interaction with smoking (AP, 0.4; 95% CI, -0.1 to 0.9). Neither smoking nor SE alleles nor their combination was associated with an increased risk of ACPA-negative RA.
    CONCLUSIONS: The risk of developing ACPA-positive RA is associated with a strong gene-environment interaction between smoking and HLA-DRB1 SE alleles in a Malaysian multiethnic population of Asian descent. This interaction seems to apply also between smoking and the specific HLA-DRB1*04:05 SE allele, which is common in Asian populations but not in Caucasians.
    Matched MeSH terms: Arthritis, Rheumatoid/immunology
  11. Farah Izati A, Wong KK, Che Maraina CH
    Malays J Pathol, 2020 Dec;42(3):333-347.
    PMID: 33361714
    Interleukin-23 (IL-23) and IL-17 are the gatekeepers of CD4+ T helper 17 (Th17) cells where IL-23 is required for the development and expansion of Th17 cells that subsequently produce IL-17 to promote inflammation. Owing to such pro-inflammatory properties, the IL-23/IL-17 axis has emerged as an important mechanism in the pathogenesis of autoimmune diseases including systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). In recent years, therapeutic antibodies targeting IL-23 (e.g. ustekinumab, tildrakizumab, guselkumab) or IL-17 (e.g. brodalumab, secukinumab, ixekizumab) have been approved for the treatment of various autoimmune diseases. In this review, we describe the pathogenic mechanisms of IL-23/IL-17 axis in SLE and RA, as well as summarising the findings from phase II and III clinical trials of anti-IL-23/IL-17 therapeutic antibodies in SLE and RA patients. In particular, phase II study has demonstrated that the anti-IL-23 antibody (ustekinumab) confers enhanced treatment outcomes in SLE patients, while anti-IL-17 antibodies (secukinumab and ixekizumab) have shown improved clinical benefits for RA patients in phase II/III studies. Our review highlights the emerging importance of targeting the IL-23/IL-17 axis in SLE and RA patients.
    Matched MeSH terms: Arthritis, Rheumatoid/immunology*
  12. Lau CS, Chia F, Dans L, Harrison A, Hsieh TY, Jain R, et al.
    Int J Rheum Dis, 2019 Mar;22(3):357-375.
    PMID: 30809944 DOI: 10.1111/1756-185X.13513
    AIM: To update recommendations based on current best evidence concerning the treatment of rheumatoid arthritis (RA), focusing particularly on the role of targeted therapies, to inform clinicians on new developments that will impact their current practice.

    MATERIALS AND METHODS: A search of relevant literature from 2014 to 2016 concerning targeted therapies in RA was conducted. The RA Update Working Group evaluated the evidence and proposed updated recommendations using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach, to describe the quality of evidence and strength of recommendations. Recommendations were finalized through consensus using the Delphi technique.

    RESULTS: This update provides 16 RA treatment recommendations based on current best evidence and expert clinical opinion. Recommendations 1-3 deal with the use of conventional synthetic disease-modifying antirheumatic drugs. The next three recommendations (4-6) cover the need for screening and management of infections and comorbid conditions prior to starting targeted therapy, while the following seven recommendations focus on use of these agents. We address choice of targeted therapy, switch, tapering and discontinuation. The last three recommendations elaborate on targeted therapy for RA in special situations such as pregnancy, cancer, and major surgery.

    CONCLUSION: Rheumatoid arthritis remains a significant health problem in the Asia-Pacific region. Patients with RA can benefit from the availability of effective targeted therapies, and these updated recommendations provide clinicians with guidance on their use.

    Matched MeSH terms: Arthritis, Rheumatoid/immunology
  13. Sockalingam S, Chow SK, Sthaneshwar P
    Int J Rheum Dis, 2009 Sep;12(3):211-5.
    PMID: 20374348 DOI: 10.1111/j.1756-185X.2009.01412.x
    AIM: The objectives of this study are to provide data regarding the prevalence of anti-cyclic citrullinated peptide (CCP) antibodies in Malaysian rheumatoid arthritis (RA) patients and to correlate the levels of anti-CCP antibody with the Disease Activity Score (DAS).
    METHOD: We studied the prevalence of anti-CCP antibodies in 51 RA patients attending our clinic and 29 controls. We also looked for correlation between anti-CCP antibody levels with the DAS and parameters such as duration of disease, rheumatoid factor (RF) and disease-modifying anti rheumatic drug (DMARD) usage.
    RESULTS: None of the controls demonstrated anti-CCP antibodies. Forty-one out of 51 patients (80.4%) were positive for anti-CCP antibodies. Sensitivity and specificity were 80.4% and 100% respectively in this study. Anti-CCP levels correlated significantly with rheumatoid factor, but no correlation was observed with the other parameters.
    CONCLUSIONS: Anti-CCP antibody is prevalent in Malaysian RA patients at 80.4% and more sensitive than RF in our cohort of established RA patients. Even though the anti-CCP levels correlated with RF, it did not show correlation with DAS.
    Matched MeSH terms: Arthritis, Rheumatoid/immunology*
  14. Maraina CH, Nurdayana AK, Rusni D, Azwany Y
    Int J Rheum Dis, 2010 Oct;13(4):335-9.
    PMID: 21199468 DOI: 10.1111/j.1756-185X.2010.01552.x
    BACKGROUND: Rheumatoid factors (RF) are currently used in the diagnosis of rheumatoid arthritis (RA). Several other autoantibodies found in RA are directed to epitopes in citrullinated proteins such as anti-cyclic citrullinated and recently anti-modified citrullinated vimentin (MCV).
    OBJECTIVE: In this study we determined the sensitivity and specificity of anti-MCV in comparison with anti-cyclic citrullinated peptide (CCP) antibodies and RF in RA patients and in a control group using the American College of Rheumatology (ACR) criteria as the gold standard.
    MATERIALS AND METHODS: A cross sectional study was conducted from January to December 2008 on 100 patients with RA and 153 patients with arthritis or arthralgia but not fulfilling ACR criteria for RA. Serum from each subject was tested for anti-MCV, anti-CCP antibodies and immunoglobulin G (IgG) RF by enzyme-linked immunosorbent assay. Sensitivity and specificity of the tests were evaluated using the ACR criteria as the gold standard.
    RESULTS: The sensitivity of RF was 85% with 74.5% specificity. For anti-CCP antibodies the sensitivity was 71% and the specificity was 94.8%. The sensitivity of anti-MCV antibodies was 80% with 59.5% specificity. The area under the curve for RF was 0.759, for anti-CCP antibodies was 0.866 and for anti-MCV antibodies was 0.681, while for at least one positive test it was 0.691.
    CONCLUSION: Anti-CCP antibodies have higher diagnostic specificity and positive predictive value than RF and anti-MCV antibodies. RF has the highest sensitivity when compared to anti-CCP and anti-MCV antibodies. Thus anti-MCV antibody is not a better marker when compared to RF or anti-MCV antibody in the diagnosis of RA patients.

    Study site: family medicine clinic, rheumatology clinic and immunology laboratory of Hospital Universiti Sains Malaysia (HUSM), Kubang Kerian, Kelantan, Malaysia
    Matched MeSH terms: Arthritis, Rheumatoid/immunology
  15. Gomez EL, Gun SC, Somnath SD, D'Souza B, Lim AL, Chinna K, et al.
    Int J Rheum Dis, 2011 Feb;14(1):12-7.
    PMID: 21303477 DOI: 10.1111/j.1756-185X.2010.01573.x
    AIM: The purpose of this study is to compare the prevalence of rheumatoid factor (RF) isotypes and second generation anti-cyclic citrullinated peptides (anti-CCP) in Malaysian rheumatoid arthritis (RA) patients.
    METHODS: In this cross-sectional study, 147 established RA patients from three ethnic groups were recruited from a major rheumatology clinic in Malaysia. Enzyme-linked immunosorbent assays (ELISA) for serum RF isotypes IgA, IgG and IgM as well as second-generation anti-CCP were performed and the prevalence of each auto-antibody was compared in the three ethnic groups.
    RESULTS: The anti-CCP was the most prevalent auto-antibody in each of the ethnic groups, followed closely by RF IgM and RF IgG. Rheumatoid factor IgA was the least prevalent across all three ethnic groups. The anti-CCP-RF IgM combination provided the best test sensitivity. Seroprevalence of anti-CCP was strongly associated with the presence of each of the RF isotypes. The seroprevalence of RF and anti-CCP did not increase or decrease with advancing age, age at onset and disease duration.
    CONCLUSION: When used alone, anti-CCP provides a diagnostic advantage over RF IgM on the basis of test sensitivity. Considering the high cost of the anti-CCP assay, step-wise serum testing with IgM RF followed by anti-CCP may provide a more economically sensible option to optimize test sensitivity for RA.
    Study site: Rheumatology clinic, Hospital Tuanku Jaafar, Seremban, Negeri Sembilan, Malaysia
    Matched MeSH terms: Arthritis, Rheumatoid/immunology*
  16. Srinivasan V, Spence DW, Trakht I, Pandi-Perumal SR, Cardinali DP, Maestroni GJ
    Neuroimmunomodulation, 2008;15(2):93-101.
    PMID: 18679047 DOI: 10.1159/000148191
    Melatonin is not only synthesized by the pineal gland but also in many other organs and tissues of the body, particularly by lymphoid organs such as the bone marrow, thymus and lymphocytes. Melatonin participates in various functions of the body, among which its immunomodulatory role has assumed considerable significance in recent years. Melatonin has been shown to be involved in the regulation of both cellular and humoral immunity. Melatonin not only stimulates the production of natural killer cells, monocytes and leukocytes, but also alters the balance of T helper (Th)-1 and Th-2 cells mainly towards Th-1 responses and increases the production of relevant cytokines such as interleukin (IL)-2, IL-6, IL-12 and interferon-gamma. The regulatory function of melatonin on immune mechanisms is seasonally dependent. This fact may in part account for the cyclic pattern of symptom expression shown by certain infectious diseases, which become more pronounced at particular times of the year. Moreover, melatonin-induced seasonal changes in immune function have also been implicated in the pathogenesis of seasonal affective disorder and rheumatoid arthritis. The clinical significance of the seasonally changing immunomodulatory role of melatonin is discussed in this review.
    Matched MeSH terms: Arthritis, Rheumatoid/immunology
  17. Too CL, Murad S, Dhaliwal JS, Larsson P, Jiang X, Ding B, et al.
    Arthritis Res Ther, 2012;14(6):R250.
    PMID: 23164236 DOI: 10.1186/ar4093
    INTRODUCTION: The majority of our knowledge regarding disease-related mechanisms of uncontrolled citrullination and anti-citrullinated protein antibody development in rheumatoid arthritis (RA) was investigated in Caucasian populations. However, peptidylarginine deiminase (PADI) type 4 gene polymorphisms are associated with RA in East Asian populations and weak or no association was found in Caucasian populations. This study explores the association between the PADI4 polymorphisms and RA risk in a multiethnic population residing in South East Asia with the goal of elucidating generalizability of association in non-Caucasian populations.
    METHODS: A total of 320 SNPs from the PADI locus (including PADI1, PADI2, PADI3, PADI4 and PADI6 genes) were genotyped in 1,238 RA cases and 1,571 control subjects from the Malaysian Epidemiological Investigation of Rheumatoid Arthritis (MyEIRA) case-control study. Additionally, we conducted meta-analysis of our data together with the previously published studies of RA from East Asian populations.
    RESULTS: The overall odds ratio (ORoverall) for the PADI4 (rs2240340) allelic model was 1.11 (95% confidence interval (CI) = 1.00 to 1.23, P = 0.04) and for the genotypic model was 1.20 (95% CI = 1.01 to 1.44, P = 0.04). Haplotype analysis for four selected PADI4 SNPs revealed a significant association of one with susceptibility (P = 0.001) and of another with a protective effect (P = 0.02). The RA susceptibility was further confirmed when combined meta-analysis was performed using these data together with data from five previously published studies from Asia comprising 5,192 RA cases and 4,317 control subjects (ORoverall = 1.23 (95% CI = 1.16 to 1.31, Pheterogeneity = 0.08) and 1.31 (95% CI = 1.20 to 1.44, Pheterogeneity = 0.32) in allele and genotype-based models, respectively). In addition, we also detected a novel association of PADI2 genetic variant rs1005753 with RA (ORoverall = 0.87 (95% CI = 0.77 to 0.99)).
    CONCLUSION: Our study demonstrates an association between PADI4 and RA in the multiethnic population from South East Asia and suggests additional association with a PADI2 gene. The study thus provides further support for the notion that polymorphisms in genes for enzymes responsible for citrullination contribute to RA development in multiple populations of Asian descent.
    Matched MeSH terms: Arthritis, Rheumatoid/immunology
  18. Meng W, Zhu Z, Jiang X, Too CL, Uebe S, Jagodic M, et al.
    Arthritis Res Ther, 2017 03 29;19(1):71.
    PMID: 28356135 DOI: 10.1186/s13075-017-1276-2
    BACKGROUND: Multiple factors, including interactions between genetic and environmental risks, are important in susceptibility to rheumatoid arthritis (RA). However, the underlying mechanism is not fully understood. This study was undertaken to evaluate whether DNA methylation can mediate the interaction between genotype and smoking in the development of anti-citrullinated peptide antibody (ACPA)-positive RA.

    METHODS: We investigated the gene-smoking interactions in DNA methylation using 393 individuals from the Epidemiological Investigation of Rheumatoid Arthritis (EIRA). The interaction between rs6933349 and smoking in the risk of developing ACPA-positive RA was further evaluated in a larger portion of the EIRA (1119 controls and 944 ACPA-positive patients with RA), and in the Malaysian Epidemiological Investigation of Rheumatoid Arthritis (MyEIRA) (1556 controls and 792 ACPA-positive patients with RA). Finally, mediation analysis was performed to investigate whether DNA methylation of cg21325723 mediates this gene-environment interaction on the risk of developing of ACPA-positive RA.

    RESULTS: We identified and replicated one significant gene-environment interaction between rs6933349 and smoking in DNA methylation of cg21325723. This gene-smoking interaction is a novel interaction in the risk of developing ACPA-positive in both Caucasian (multiplicative P value = 0.056; additive P value = 0.016) and Asian populations (multiplicative P value = 0.035; additive P value = 0.00027), and it is mediated through DNA methylation of cg21325723.

    CONCLUSIONS: We showed that DNA methylation of cg21325723 can mediate the gene-environment interaction between rs6933349 and smoking, impacting the risk of developing ACPA-positive RA, thus being a potential regulator that integrates both internal genetic and external environmental risk factors.
    Matched MeSH terms: Arthritis, Rheumatoid/immunology
  19. Toh BH, Sengupta S, Ang AH, White JC, Lau KS
    Ann Rheum Dis, 1973 Mar;32(2):151-6.
    PMID: 4120913 DOI: 10.1136/ard.32.2.151
    In West Malaysia RA appears to be less common than in temperate climates, but more common than in tropical Africa; furthermore, the incidence of gout and SLE is comparable. The clinical manifestations of RA are milder than those seen in more temperate climates. Subcutaneous rheumatoid nodules have not been observed. Positive serological tests for RF are significantly higher than in the general Malaysian population, but still lower than those reported for patients with RA in temperate climates. Of the three main ethnic groups, the highest incidence of positive results is found in the Chinese.
    Study site: Arthritis Clinic, University Hospital, Kuala Lumpur (University Malaya Medical Centre, UMMC, Kuala Lumpur, Malaysia)
    Matched MeSH terms: Arthritis, Rheumatoid/immunology
  20. Sakthiswary R, Shaharir SS, Mohd Said MS, Asrul AW, Shahril NS
    Int J Rheum Dis, 2014 Nov;17(8):872-7.
    PMID: 25292482 DOI: 10.1111/1756-185X.12443
    AIM: The main objective of this study is to elucidate the role of immunoglobulin A (IgA) rheumatoid factor (RF) in predicting the clinical response to tumour necrosis factor α inhibitors (TNFi) among patients with rheumatoid arthritis (RA).
    METHOD: We recruited all patients with RA who were ever on TNFi for a minimum duration of 3 months at our centre. Based on the European League Against Rheumatism response criteria, subjects were further divided into responders and non-responders. Age-matched RA patients who were on conventional disease-modifying anti-rheumatic drugs and in remission were enrolled as controls. Subjects were tested for quantitative values of IgA, IgM, IgG RF and anti-citrulinated cyclic peptides (CCP). Further, all subjects were assessed for the disease activity score that includes 28 joints (DAS28) and Stanford Health Assessment Questionnaire (HAQ) 8-item Disability Index (HAQ-DI).
    RESULTS: A total of 31 subjects with RA who had received TNFi and 15 controls were enrolled in this study. There was a trend for the non-responders (n = 10) to have higher levels of all isotypes of RF and anti-CCP. However, only the IgA RF and anti-CCP levels were significantly higher in the non-responder group compared to the responders and controls (P = 0.001, P = 0.034, respectively). On multivariate analysis, only the IgA RF remained significant (OR 0.989; 95% CI 0.980-0.999; P = 0.026).
    CONCLUSION: IgA RF is potentially a novel predictor of response to TNFi in RA patients. Testing for pretreatment IgA RF levels could be a reasonable consideration before commencement of TNFi.
    Study site: Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia
    Matched MeSH terms: Arthritis, Rheumatoid/immunology
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links