Abstract: Ding Yan*, He Xiaojie, Liao Wang, Yang Huilan, Xiang Wei, Dang Xiqiang, Yi Zhuwen. *Graduate School of Southern Medical University, Guangzhou 510015, China Corresponding authors: Yang Huilan, Email: huilany88@hotmail.com; Xiang Wei, Email: xiangwei8@163.com 【Abstract】 Objective To investigate the expression and significance of Epstein-Barr virus （EBV） genes in children with systemic lupus erythematosus （SLE）. Methods Peripheral blood mononuclear cells （PBMCs） were isolated from 20 children with SLE and 12 healthy human controls. Enzyme-linked immunosorbent assay （ELISA） was conducted to detect anti-EBV viral capsid antigen （VCA） IgG/IgM antibodies. The culture supernatants of cells from patients with anti-EBV VCA IgG/IgM antibodies were collected, and PBMCs from the patients and controls were co-cultured with the supernatants respectively for 12 days. RNA was extracted from PBMCs before and after the coculture, and reverse transcription-PCR was performed to detect the expression of EBV genes, including LMP1, LMP2, EBNA1, BCRF1, BLLF1 and BILF1 genes. Results LMP1 gene was detected in fresh PBMCs from 10 out of 20 patients and 1 out of 12 controls （P < 0.05）. No significant differences were observed between the patients and controls in the detection rate of LMP2 gene （4/20 vs. 1/12）, EBNA1 gene （13/20 vs. 3/12）, BCRF1 gene （3/20 vs. 1/12） or BLLF1 gene （5/20 vs. 2/12） in fresh PBMCs. After co-culture with the supernatants of cells from patients with anti-EBV VCA IgG/IgM antibodies, the expressions of EBV genes in these PBMCs were increased to different degrees, and there was a significant difference in the expressions of EBV latent genes LMP1, LMP2 and EBNA-1 as well as EBV replicative genes BCRF1 and BLLF1 between the patient-derived and control-derived PBMCs （all P < 0.05）. Conclusions There is an aberrant expression of EBV genes in children with SLE, and EBV genes may contribute to the development of SLE.

Key words: Lupus erythematosus, systemic, Epstein-Barr virus infections, Gene expression, Child