目的观察抗凋亡蛋白HAX-1对MRL/lpr狼疮鼠狼疮活动性的影响。方法重组腺病毒AdHAX-1经腹腔注射MRL/lpr小鼠,每周2次,连续注射4周。分别在注射前、注射2周后及4周后检测小鼠血清中抗核抗体(ANA)、循环免疫复合物(CIC)、抗双链DNA抗体(抗dsDNA抗体)、抗组蛋白抗体和干扰素γ(IFN-γ)水平,并检测注射前及注射后外周血的白细胞计数及尿蛋白水平;经RNAi使HAX-1表达下调后,观察脾脏淋巴细胞的增殖以及IFN-γ的分泌水平。结果HAX-1可使MRL/lpr小鼠的尿蛋白以及抗dsDNA抗体、ANA、抗组蛋白抗体、CIC明显升高,且产生IFN-γ水平升高,除抗组蛋白抗体及CIC外,其余指标与磷酸盐缓冲液对照组(PBS组)及对照腺病毒组(AdEGFP组)相比较,差异均有统计学意义(均P〈0.05)。重组腺病毒组(AdHax-1组)小鼠肾小球内免疫复合物沉积强度明显较强且阳性肾小球数目较多,与对照组比较差异均有统计学意义(均P〈0.05)。AdHax-1组肾小球的平均病变积分达1.50±0.34,与对照组(PBS组:0.67±0.14;AdEGFP组:0.81±0.26)比较差异均有统计学意义(均P〈0.01)。pGenesil-HAX-1可使淋巴细胞的增殖率明显降低(P〈0.05),IFN-γ分泌水平明显下降(P〈0.01)。结论HAX-1是调节系统性红斑狼疮淋巴细胞凋亡的一个重要因素,重组AdHAX-1可使MRL/lpr小鼠狼疮样症状加重,下调HAX-1表达可使病情减轻。
Objective To investigate the effects of HS1-associated protein X-1 (HAX-1) on the lupus activity of MRL/lpr lupus-like mice. Methods Fifteen MRL/lpr mice were divided into 3 equal groups: Group A, injected with phosphate-buffered saline, Group B, injected intraperitoneally with control virus AdEGFP and Group C, injected intraperitoneally with recombinant AdHAX-1 twice a week for 4 weeks. Peripheral blood samples were collected before the injection, and 2 and 4 weeks after the injection to be detected the white blood cell count, antinuclear antibody ( ANA), anti-double strand-DNA antibodies, circulating immune complex (CIC) , anti-histone antibodies, and interferon (IFN) -γ. The level of urine protein was measured, too. Then the mice were killed, a kidney underwent direct immunofluorescence (DIF) to observe the deposition of Immune complexes, and the other kidney underwent periodic acid-Schiff (PAS) staining and pathological examination. MTT method was used to detect the proliferation of the lymphocytes in the spleen. Splenocytes were isolated from the other 15 MRL/lpr mice and then divided into 4 groups: Group, transfected with DMRIE-C without plasmid; Group E, as negative control group; Group F, transfected with blank plasmid pGenesil-1 ; and Group G, transfected with pGenesil-HAX-1. Forty-eight hours later MTT method was used to detect the proliferation rateof the spleen lymphocytes. Results The urine protein level of Group C was significantly higher than those of Groups A and B ( both P 〈0.01 ). Four weeks later the levels of ANA, anti-double strand DNA antibodies, and IFN-γ were all significantly higher than those of Groups A and B (all P 〈0.01). Hypercellularity and increased deposition of IgG in glomeruli were also observed in Group C. The score of glomeruli lesion of Group C (1.50 ± 0. 34) was significantly higher than those of Groups A (0.67±0.14) and Groups B (0.81±0.26) (both P〈0.01). MTT method showed that the growth curve of the spleen lym