大鼠矽肺模型对绵羊红细胞抗原的免疫应答

Immune responses of silicotic rats to the antigen of sheep red blood cells

目的 探讨大鼠矽肺模型对绵羊红细胞 (SRBC)抗原的免疫应答。方法 矽肺模型大鼠分别通过气道、腹腔给予SRBC ,观察其血清溶血素、血清与肺泡灌洗液特异性IgG水平的动态变化、皮肤迟发型变态反应 (DTH)以及肺引流淋巴结、肺泡灌洗液细胞总数和分类计数。结果 (1 )第一次抗原免疫后第 7、1 2、2 0、2 5、32天 ,第二次抗原免疫后第 5、1 2、1 5天 ,矽肺气道免疫组大鼠血清溶血素半数溶血指数 (HC50 )分别为 47.4± 1 .0、52 .2± 4 .6、31 .1± 1 1 .9、43 .8± 3 .5、33 .6± 1 6 .8、49.0± 2 .3、92 .9± 2 0 .2、87.7± 5 .2 ,高于正常对照组 (分别为 40 .4± 1 0 .6、2 .8± 2 .5、0 .8± 0 .6、6 .6± 5 .8、1 .4±0 .1、36 .5± 1 6 .5、53 .0± 33 .2、2 .6± 2 .2 ) ,差异均有显著性 (P <0 .0 1 )。 (2 )第一次抗原免疫后第 1 2、2 0、2 5、32天 ,第二次抗原免疫后第 5、1 2、1 5、2 7天 ,矽肺气道免疫组大鼠血清特异性IgG(A4 90 nm值 )分别为 1 .67± 0 .1 9、1 .98± 0 .36、1 .1 2± 0 .50、1 .38± 0 .30、2 .75± 0 .1 5、2 .60± 0 .2 8、2 .86± 0 .1 0、2 .50±0 .2 0 ,高于正常对照组 (分别为 0 .59± 0 .30、0 .56± 0 .2 1、0 .2 1± 0 .1 6、0 .2 2± 0 .1 0、0 .81± 0 .2 5。

Objective To explore the immune response of silicotic rats to sheep red blood cells(SRBC). Methods Silicotic rats were immunized with SRBC by tracheal instillation(Group 1) or intraperitoneal injection(Group 2),and non silicotic rats were immunized by tracheal instillation as normal control(Group 3).The levels of serum hemolytic index(HC 50 ) were measured on 7,12,20,25,and 32 days after primary immunization and 5,12,15 days after the second immunization.Special anti SRBC IgG was measured with ELISA( A 490 nm ) on 12,20,25,32 days and 5,12,15,27 days respectively.Delayed type hypersensitivity(DTH) to SRBC was measured 20 days after second immunization and DTH reaction was determined at 24,48,72,and 96 h after administration.Total cell count and cell populations in the bronchoalveolar lavage fluid(BALF),lung associated lymph node(LALN) and spleen weight,special IgG secreted from spleen cells were measured at the end of the experiment. Results The HC 50 of Group 1(47.4± 1.0 ,52.2±4.6,31.1±11.9,43.8±3.5,33.6±16.8,49.0±2.3, 92.9 ±20.2,87.7± 5.2) were statistically higher than those of Group 3(40.4±10.6,2.8±2.5,0.8±0.6,6.6±5.8,1.4± 0.1 ,36.5± 16.5 ,53.0±33.2,2.6±2.2).The special anti SRBC IgG response in Group 1(1.67±0.19,1.98±0.36,1.12± 0.50 ,1.38±0.30,2.75±0.15,2.60±0.28,2.86±0.10,2.50±0.20) were much stronger than those in Group 3(0.59±0.30,0.56±0.21,0.21±0.16,0.22±0.01,0.81±0.25,0.74±0.25,0.69±0.26,1.38±0.41).Furthermore,the results of DTH showed positive response and the ratios for diameter of skin rash>5 mm at 24,48,72,96 h were 16/16,16/16,16/16,15/16 respectively in Group 1,while those in Group 3 were 8/15,1/15,1/15,1/15 respectively.Total cell count in the BALF,LALN and spleen weight,and special IgG secreted from spleen cells in Group 1 were higher too.Group 2 expressed almost of the same but with mild immunologic responses as Group 1. Conclusion Silicosis induced extremely strong DTH and over response of humoral immunity to some antigens may contribute to the likelihood of silicosis complicated with tuberculosis.