The Expression Of The Defensins In The Activity Of The Systemic Lupus Erythematosus And Their Relation With Lung Infection

Objective To observe the expression of defensins in the activeperiod of the systemic lupus erythematosus (SLE) and their relation withlung infection, detecting the level of TNF-αin plasma to discuss theinfection mechanism from the molecule level in order to search a newmethod to prevent the infection to the SLE sufferers and cure them.Methods Eighty persons were selected, including 20 with activeSLE ,20 with stable SLE, 20 SLE patients with lung infection, and therest were healthy. The expression ofα- defensin andβ- defensin mRNAin leucocytes of the lung infection group were detected by reversetranscription polymerase chain reaction (RT-PCR) ;the levels of TNF-αin serum were detected by enzyme-linked immunosorbent assay(ELISA).Result 1) There's a significant difference between the activeSLE group and the stable SLE group (P＜0.001). 2) The expression ofα-defensin in active SLE group was significantly lower than in the lunginfection group (P＜0.001). 3) The expression ofα-defensin in those withlung infection who received antibiotics treatment was downreglated (P＜0.001). 4)β-defensin wasn't detected in peripheral blood leucocytes inall volunteers. 5)The levels of TNF-αin the plasma of the SLE patientswere much higher than the healthy controls (P＜0.01). The levels of TNF-αwere much higher in active SLE group than in stable SLE group(P＜0.001). The levels of TNF-αwere lower in post-treatment group than inlung infection group(P＜0.001).6)The expression of theα-defensin-mRNAwas found positively correlated with TNF-α(P＜0.001, r=0.0.498),CRP (P＜0.001, r=0.922) and ESR level (P＜0.001, r=0.902), andnegatively correlated with C₃ level (P＜0.001, r=-0.82)Conclusionα-defensin may play an important role in systemiclupus erythematosus and secondary lung infection to SLE.The level ofα-defensin-mRNA closely associates with the lupus activety of SLEpatients.