EXPERIMENTAL-STUDY ON INTRAMUSCULAR INJECTION OF EUKARYOTIC EXPRESSION VECTOR PCDNA3-IL-6 ON BXSB MICE

Objective To study the role of IL-6 in systemic lupus erythematosus (S LE). Methods We constructed eukaryotic expression vector pcDNA3-IL-6 e ncoding for IL-6 and injected it intramuscularly into BXSB mice. 22 of the 3.5-month-old male BXSB mice were divided into two groups. One gr oup was injected with the pcDNA3-IL-6 100 mu g per mouse twice at the interval of 20 days. Another group was injected with plasmid pcDNA3 at the same time as control. The ANA and proteinuria were monitored ever y 10 days, and the IL-6 activity in serum, IgG, C3 deposition and IL-6 expression in kidney detected at the 40th day. Results IL-6 encoding plasmid had harmful effects on murine SLE with increased ANA level, pr oteinuria, IgG, C3 deposition and IL-6 expression in kidney, but there was no difference of serum GPT levels between the two groups. Conclus ion Excessive production of IL-6 could play an important pathogenic ro le in SLE. Blocking or reducing IL-6 secretion might be a new therapy for SLE.