Abstract: KANG Er-xun*, LI Jie, SUN Li-wei, HAN Chun-yu, YAN Li-ping, YANG Jian. *Department of Dermatology, Affiliated Yantai Yuhuangding Hospital, Medical College of Qingdao University, Yantai 264000, Shandong, China Corresponding author: KANG Er-xun, Email: kangerxun2000@163.com 【Abstract】 Objective To explore if B lymphocyte stimulator （BlyS） stimulates B lymphocytes from patients with chronic idiopathic urticaria （CIU） to produce anti-high affinity IgE receptor （FcεRI） or anti-IgE antibodies. Methods Totally, 300 CIU patients and 300 health controls were enrolled in this study. Blood samples were obtained from these subjects. Peripheral blood B lymphocytes were isolated and cultured in vitro for 72 hours. Then, BlyS of various concentrations （2, 4, 8, 16 ng/ml） was added to the culture medium of B lymphocytes followed by another 72-hour culture. Enzyme-linked immunosorbent assay was performed to determine the serum levels of BlyS, anti-FcεRI and anti-IgE antibodies, as well as the supernatant levels of anti-FcεRI and anti-IgE antibodies. The relationship between BlyS and anti-FcεRI and anti-IgE antibody production was assessed. SPSS software version 16.0 was used for statistical analysis. Chi-square test was performed to compare the positivity rate of antibodies, and analysis of variance and least significance difference-t test to assess numerical data. Results The CIU patients showed higher levels of serum BlyS（t = 3.04, P < 0.01）, anti-FcεRI antibodies（t = 3.51, P < 0.01）, and anti-IgE antibodies （t = 3.29, P < 0.01） compared with the health controls. The serum level of BlyS was positively correlated with that of anti-FcεRI antibodies （r = 0.93, P < 0.01） and anti-IgE antibodies （r = 0.91, P < 0.01）. The levels of anti-FcεRI antibodies and anti-IgE antibodies were significantly increased in the culture supernatant of patient-derived B lymphocytes treated with BlyS compared with those remaining untreated （t = 3.67, 3.56, respectively, both P < 0.01）, and the concentration of BlyS was positively correlated with the levels of both anti-FcεRI antibodies and anti-IgE antibodies（r = 0.96, 0.91, respectively, both P < 0.01）. The coincidence rate between the serum and supernatant was 94.76% and 87.84% in the detection of anti-FcεRI antibodies and anti-IgE antibodies respectively. Conclusions BlyS level is upregulated in the serum of patients with CIU, which may play an important role in the pathogenesis of CIU by stimulating B lymphocytes to produce anti-FcεRI antibodies or anti-IgE antibodies. 【Key words】 Urticaria; B cell activating factor; Antibodies, FcεRI; Antibodies, IgE; B-lymphocytes

Key words: B lymphocyte stimulator