Immunoglobulin G subclasses and clinical significance of patients with primary Sj(o)gren's syndrome / 中华风湿病学杂志

ABSTRACT

Objective To investigate the clinical significance of IgG subclasses in patients with primary Sj(o)gren's syndrome (pSS) patients.Methods The serum was collected from 101 pSS patients and 40 healthy subjects.The content of IgG subclasses was determined by immuno-scatter turbidmetry.The difference of IgG subclasses distribution between pSS patients and healthy subjects was analyzed.Com-bined with the clinical information of the SS patients,the difference of IgG subclasses distribution in SS patients with different characteristics was analyzed.For group comparisons,measurement data were compared using unpaired Student's t test.Results The average levels of serum IgG1-4 in 40 healthy controls were (8085±1566) mg/L,(5406±2151) mg/L,(395±233) mg/L and (566±420) mg/L.The percentage of IgG1-4 were (56.8±8.2)％,(36.6±7.8)％,(2.7±1.5)％ and (3.9±2.8)％.The average levels of serum IgG1-4 in 101 pSS patients were (14 094±5534) mg/L,(3912±1750) mg/L,(565±565) mg/L and (404±504) mg/L,The percentage of IgG1-4 were(73.0±10.9)％,(21.7±9.8)％,(3.1±2.0)％ and (2.2±2.4)％.In pSS patients,the levels of IgG1,IgG3 and IgG1/IgG were significantly higher,while the IgG2,IgG2/IgG and IgG4/IgG levels were significantly lower,compared with those of the healthy subjects (P＜0.05).There was no significant difference in the IgG subclasses distribution between the pSS patients whose had systemic involvement and the pSS patients who did not have systemic involvement(P＞0.05).The IgG subclasses distribution was abnormal in SS patients who IgG was normal,compared with the healthy subjects.Conclusion A characteristic IgG subclasses distribution abnormality exists in pSS patients,and the production of anti-SSA (Sj(o)gren's syndrome A) antibody is associated with the increase of IgG1.However,no relationship has been found between the systemic involvement of pSS patients and the abnormal distribution of IgG subclasses.