Araujo Galber R, Fonseca João E, Fujimura Patricia T, Cunha-Junior Jair P, Silva Carlos H M, Mourão Ana F, Canhão Helena, Goulart Luiz R, Gonçalves João, Ueira-Vieira Carlos
Laboratory of Nanobiotecnology, Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Uberlândia, Brazil; iMed - Instituto de Medicina, Faculdade de Farmácia da Universidade de Lisboa, Lisbon, Portugal.
Rheumatology Research Unit, Instituto de Medicina Molecular, Lisbon, Portugal; Rheumatology Department, Lisbon Academic Medical Center, Lisbon, Portugal.
Immunol Lett. 2015 May;165(1):20-5. doi: 10.1016/j.imlet.2015.03.006. Epub 2015 Mar 20.
Juvenile idiopathic arthritis (JIA) refers to a heterogeneous group of illnesses that have in common the occurrence of chronic joint inflammation in children younger than 16 years of age. The diagnosis is made only on clinical assessment. The identification of antibody markers could improve the early diagnosis, optimizing the clinical management of patients. Type II collagen is one potential autoantigen that has been implicated in the process of arthritis development. The aims of our study were to investigate the occurrence of anti-type II collagen antibodies and also to determine the avidity of the antibody-antigen binding. Ninety-six patients with oligoarticular or polyarticular JIA, 13 patients with ankylosing spondylitis (AS) and 61 healthy controls (HC) were tested for anti-type II collagen antibodies by ELISA and avidity ELISA. Sensitivity and specificity were determined by the receiver operating characteristic (ROC) curve analysis. Forty-two JIA patients (44%) were positive for antibodies against type II collagen. Its detection was significantly higher in JIA patients than in AS patients (p=0.006) and HCs (p<0.0001). Furthermore, anti-type II collagen antibody detection was significantly more frequent in patients with JIA of ≤6 months duration (p=0.0007). Antibodies displaying high avidity to type II collagen were associated with disease activity (p=0.004). This study demonstrates that antibodies against type II collagen are present in the serum of patients with oligoarticular and polyarticular JIA, being its presence more prevalent in patients with early disease. It also demonstrates that JIA patients with active disease present antibodies with high avidity against type II collagen.
青少年特发性关节炎（JIA）是一组异质性疾病，其共同特征是16岁以下儿童出现慢性关节炎症。仅通过临床评估进行诊断。抗体标志物的识别可以改善早期诊断，优化患者的临床管理。II型胶原蛋白是一种潜在的自身抗原，与关节炎的发展过程有关。我们研究的目的是调查抗II型胶原蛋白抗体的发生率，并确定抗体-抗原结合的亲和力。通过酶联免疫吸附测定（ELISA）和亲和力ELISA对96例少关节型或多关节型JIA患者、13例强直性脊柱炎（AS）患者和61例健康对照（HC）进行抗II型胶原蛋白抗体检测。通过受试者操作特征（ROC）曲线分析确定敏感性和特异性。42例JIA患者（44%）抗II型胶原蛋白抗体呈阳性。其在JIA患者中的检测率显著高于AS患者（p=0.006）和健康对照（p<0.0001）。此外，病程≤6个月的JIA患者抗II型胶原蛋白抗体检测更为频繁（p=0.0007）。对II型胶原蛋白显示高亲和力的抗体与疾病活动相关（p=0.004）。本研究表明，少关节型和多关节型JIA患者血清中存在抗II型胶原蛋白抗体，其在疾病早期患者中更为普遍。它还表明，患有活动性疾病的JIA患者存在对II型胶原蛋白具有高亲和力的抗体。
