禽巴氏杆菌荚膜多糖-蛋白载体抗原的研究

STUDIES ON THE CARRIER ANTIGENS OF P.MULTOCIDA CAPSULAR POLYSACCHARIDE AND TATANUS TOXOID CONJUGATES

用EDC法和CNBr法分别交联禽巴氏杆菌荚膜多糖(CPS)与破伤风类毒素(TT),经Sephadex-G150柱层析和薄层层析鉴定表明;两种方法均获得一种大分子的CPS-TT结合物,该结合物免疫鸡的血清经二巯基乙醇(2-ME)处理后用间接血凝试验(IHA)检测出较高滴度的IgG抗体和一定量的IgM抗体,抗体消长情况监测结果;IgG抗体的峰值(4.88)在免疫后第21天,其后缓慢下降,持续至第24周左右。IgM抗体的峰值(4.26)在第14天,其后陡降,至第8周降至阴性血清水平,与对照组差异极显著(P<0.01)。第8周和第24周时测出较强的二次反应和回忆反应。重复试验测出的IgG、IgM抗体滴度与本试验结果相近,第4周时攻毒保护率分别为100％和75％,且IgG抗体滴度与攻毒保护率的相关性较好,1:16以上可获得全保护。试验结果表明交联方法稳定,重复性较好,制备的CPS-TT载体抗原实现了CPS由Ti抗原向Td抗原的转换。为研究一种新型的禽霍乱载体菌苗提供了理论依据和实验手段。

In the present study, N-ethyl-N'- ( 3-dimethylaminopropyl ) Carbo-diimide ( EDC ) and Cyanogen Bromide ( CNBr ) were used as the conjugates of P.multocida Capsular Polysaccharide ( CPS ) and Tatanus Tox-oid ( TT ) . The biochemical tests showed that CPS-TT was a new conjugate of high molecular weight. The serum of the chickens vaccinated with CPS-TT was treated with 2-ME. The indirect hemagglutina- tion test(IHA)detected that CPS-TTmainly induced IgG. However, there were some IgM in the initial period after inoculation. A pead titer of IgG appeared after 3 weeks, later the titer of IgG decreased slowly and sustained to about 24 week. A Peak titer of IgM appeared after 2 weeks, later the titer of IgM decreased rapidly and sustained only 8 weeks. The titers of IgG and IgM were different significantly compared with those of the control chickens ( P<0.01 ) . Vigorously immunologi-cal memory responses were detected in chickens inoculated with CPS-TT at the 24th week. The repeated experiments Showed that there were a higher titer of IgG and IgM in the serum at 4th week and protection rates were 100 and 75 percentage respectively. The results suggested that the coupling methods might be repeated. The carrier antigens of CPS-TT prepared realized the transformation of the CPS from Thymus-independent Antigens(Ti)to Thymus-dependent Antigens ( Td ) . The carrier of the Tatanus Totoxoid strengthened the ability of the immunological response of CPS and lengthened the immunization period of CPS.