克隆氏病Crohn(?)Disease是一种发病率日益增长而原因不明的炎症性肠道疾病。病变部位的单核细胞浸润提示该病可能涉及到免疫机制。然而在本病中曾被认为与损害机理和疾病活动直接有关的各种免疫学异常却未曾报告过。β_2-小球蛋白是一种与细胞膜上HLA抗原的重链非共价结合的低分子蛋白,其结构显示与免疫球蛋白十分相似。淋巴细胞激活可以增加β_2-小球蛋白自T和B细胞的释放,这种蛋白的血清水平增高见于淋巴增生性和自家免疫性疾病,如Sj(?)gren′s综合症和类风湿关节炎。作者研究了36名克隆氏病患者β_2-小球蛋白水平,其中男性19名,女性17名,年龄13～66岁(中位数——38岁)。克隆氏病的诊断是根据目前公认的临床、放射和病理学诊断标准。9名病人有回肠炎, Crohn’s disease Crohn’s disease is an inflammatory bowel disease with an increasing incidence and an unknown cause. Mononuclear cell infiltration at the lesion suggests that the disease may be involved in the immune mechanism. However, a variety of immunological abnormalities that were previously considered to be related to impairment mechanisms and disease activity have not been reported in this disease. β_2-microglobulin is a low-molecular-weight protein that binds non-covalently to the heavy chain of the HLA antigen on the cell membrane and shows a structure very similar to immunoglobulins. Lymphocyte activation increases the release of β_2-microglobulin from T and B cells. Elevated serum levels of this protein are found in lymphoproliferative and autoimmune diseases such as Sjögren’s syndrome and rheumatoid arthritis . The authors studied β2-microglobulin levels in 36 patients with Crohn’s disease, 19 of them male and 17 female, aged 13-66 years (median -38 years). The diagnosis of Crohn’s disease is based on currently accepted clinical, radiological and pathological diagnostic criteria. Nine patients had ileitis,