Tsutsumi Akito, Takahashi Reiko, Sumida Takayuki
Division of Clinical Immunology, Graduate School of Comprehensive Human Sciences, University of Tsukuba 1-1-1, Tennodai, Tsukuba 305-8575, Ibaraki, Japan.
Autoimmun Rev. 2005 Jul;4(6):364-72. doi: 10.1016/j.autrev.2005.02.004. Epub 2005 Apr 13.
Mannose binding lectin (MBL) is a serum protein with structure and functions similar to those of complement factor C1q, and is a key molecule in innate immunity. Interestingly, absence or extremely low concentration of serum MBL (MBL deficiency) seems to be a risk factor for occurrence of autoimmune diseases, in particular systemic lupus erythematosus. In addition, individuals with MBL deficiency are at risk of infection when in immunocompromised conditions. The concentration of serum MBL is greatly influenced by relatively common single nucleotide polymorphisms of the MBL gene. Therefore, typing of the MBL gene, or measurement of serum MBL may be valuable for determining the risk of infections in patients with systemic autoimmune diseases, who frequently undergo immunosuppressive therapies. MBL deficiency may also be a risk factor for atherosclerosis and arterial thrombosis, both being common complications of autoimmune diseases. On the other hand, MBL may be pathological in tissue injuries, and the precise roles of MBL in autoimmune diseases, and the value of MBL gene typing or serum MBL measurement in a clinical setting are yet to be clarified. Recently, presence of anti-MBL autoantibodies in sera of SLE patients has been reported. The significance of this autoantibody remains to be elucidated.
甘露糖结合凝集素（MBL）是一种血清蛋白，其结构和功能与补体因子C1q相似，是固有免疫中的关键分子。有趣的是，血清MBL缺失或浓度极低（MBL缺陷）似乎是自身免疫性疾病，尤其是系统性红斑狼疮发生的危险因素。此外，MBL缺陷个体在免疫功能低下时存在感染风险。血清MBL浓度受MBL基因相对常见的单核苷酸多态性的极大影响。因此，MBL基因分型或血清MBL检测对于确定经常接受免疫抑制治疗的系统性自身免疫性疾病患者的感染风险可能具有重要价值。MBL缺陷也可能是动脉粥样硬化和动脉血栓形成的危险因素，这两者都是自身免疫性疾病的常见并发症。另一方面，MBL在组织损伤中可能具有病理性，MBL在自身免疫性疾病中的精确作用以及MBL基因分型或血清MBL检测在临床环境中的价值尚待阐明。最近，有报道称系统性红斑狼疮患者血清中存在抗MBL自身抗体。这种自身抗体的意义仍有待阐明。
