Bakri Hassan A, Rönnelid J, Gunnarsson I, Karlsson G, Berg L, Lundberg I
Department of Rheumatology, Karolinska Institute, Stockholm, S-171 76, Sweden.
J Autoimmun. 1998 Oct;11(5):503-8. doi: 10.1006/jaut.1998.0236.
It is controversial whether mixed connective tissue disease (MCTD) should be regarded as a distinct disease entity. In the present study, we investigated immunological parameters in patients with MCTD by studying serum levels of immunoglobulins, C-reactive protein (CRP) and cytokines and compared the results to the corresponding values in systemic lupus erythematosus (SLE), in rheumatoid arthritis (RA) patients and in healthy controls. Using the ELISA technique, serum levels of the cytokines interferon-gamma (IFN-gamma), interleukin-10 (IL-10) and tumour necrosis factor-alpha (TNF-alpha) were investigated. Cytokine levels in SLE and MCTD were correlated to disease activity as assessed by systemic lupus activity measure (SLAM). They were also correlated to serum levels of CRP, IgG, IgA and IgM in the three patient groups. The MCTD patients had the highest levels of immunoglobulins, followed by the SLE patients. In contrast, the highest CRP levels were observed in RA patients, followed by the MCTD patients. The MCTD patients had the highest serum levels of IL-10, but also had elevated IFN-gamma and TNF-alpha levels similar to the RA patients. There was no correlation between the investigated cytokine levels and disease activity, as assessed by SLAM. We conclude that MCTD patients have high immunoglobulin levels as well as high CRP levels and that this situation is compatible with the observed increase in both type 1 and type 2 cytokine levels. The findings imply that MCTD shares some distinct immunological properties with both RA and SLE and that MCTD may also be considered as a separate disease entity according to these properties.
混合性结缔组织病（MCTD）是否应被视为一种独特的疾病实体存在争议。在本研究中，我们通过研究免疫球蛋白、C反应蛋白（CRP）和细胞因子的血清水平，调查了MCTD患者的免疫学参数，并将结果与系统性红斑狼疮（SLE）、类风湿关节炎（RA）患者及健康对照者的相应值进行比较。采用酶联免疫吸附测定（ELISA）技术，研究了细胞因子γ干扰素（IFN-γ）、白细胞介素-10（IL-10）和肿瘤坏死因子-α（TNF-α）的血清水平。SLE和MCTD患者的细胞因子水平与通过系统性红斑狼疮活动度测量（SLAM）评估的疾病活动度相关。它们还与三组患者的CRP、IgG、IgA和IgM血清水平相关。MCTD患者的免疫球蛋白水平最高，其次是SLE患者。相比之下，RA患者的CRP水平最高，其次是MCTD患者。MCTD患者的IL-10血清水平最高，但IFN-γ和TNF-α水平也升高，与RA患者相似。通过SLAM评估，所研究的细胞因子水平与疾病活动度之间无相关性。我们得出结论，MCTD患者的免疫球蛋白水平和CRP水平都很高，这种情况与观察到的1型和2型细胞因子水平升高相符。这些发现表明，MCTD与RA和SLE都具有一些独特的免疫学特性，并且根据这些特性，MCTD也可被视为一种独立的疾病实体。
