School of Biochemistry, Genetics and Microbiology, University of KwaZulu-Natal (Pietermaritzburg campus), Private Bag X01, Scottsville, 3209, South Africa.
Vet Res. 2009 Nov-Dec;40(6):52. doi: 10.1051/vetres/2009036. Epub 2009 Jun 24.
The protozoan parasite Trypanosoma congolense is the main causative agent of livestock trypanosomosis. Congopain, the major lysosomal cysteine proteinase of T. congolense, contributes to disease pathogenesis, and antibody-mediated inhibition of this enzyme may contribute to mechanisms of trypanotolerance. The potential of different adjuvants to facilitate the production of antibodies that would inhibit congopain activity was evaluated in the present study. Rabbits were immunised with the recombinant catalytic domain of congopain (C2), either without adjuvant, with Freund's adjuvant or complexed with bovine or rabbit alpha(2)-macroglobulin (alpha(2)M). The antibodies were assessed for inhibition of congopain activity. Rabbits immunised with C2 alone produced barely detectable anti-C2 antibody levels and these antibodies had no effect on recombinant C2 or native congopain activity. Rabbits immunised with C2 and Freund's adjuvant produced the highest levels of anti-C2 antibodies. These antibodies either inhibited C2 and native congopain activity to a small degree, or enhanced their activity, depending on time of production after initial immunisation. Rabbits receiving C2-alpha(2)M complexes produced moderate levels of anti-C2 antibodies and these antibodies consistently showed the best inhibition of C2 and native congopain activity of all the antibodies, with maximum inhibition of 65%. Results of this study suggest that antibodies inhibiting congopain activity could be raised in livestock with a congopain catalytic domain-alpha(2)M complex. This approach improves the effectiveness of the antigen as an anti-disease vaccine candidate for African trypanosomosis.
原生动物寄生虫锥虫是造成牲畜锥虫病的主要病原体。锥虫蛋白酶，T. congolense 的主要溶酶体半胱氨酸蛋白酶，有助于疾病发病机制，并且这种酶的抗体介导的抑制作用可能有助于锥虫耐受的机制。本研究评估了不同佐剂促进产生抑制锥虫蛋白酶活性的抗体的潜力。用重组锥虫蛋白酶（C2）催化结构域免疫兔子，要么没有佐剂，要么用福氏佐剂或与牛或兔α（2）-巨球蛋白（α（2）M）复合。评估了这些抗体抑制锥虫蛋白酶活性的能力。单独用 C2 免疫的兔子产生几乎检测不到的抗 C2 抗体水平，这些抗体对重组 C2 或天然锥虫蛋白酶活性没有影响。用 C2 和福氏佐剂免疫的兔子产生最高水平的抗 C2 抗体。这些抗体要么在一定程度上抑制 C2 和天然锥虫蛋白酶的活性，要么根据初次免疫后的产生时间增强其活性。接受 C2-α（2）M 复合物的兔子产生中等水平的抗 C2 抗体，这些抗体始终显示出对所有抗体中最好的 C2 和天然锥虫蛋白酶活性的抑制作用，最大抑制率为 65%。这项研究的结果表明，可以用锥虫蛋白酶催化结构域-α（2）M 复合物在牲畜中产生抑制锥虫蛋白酶活性的抗体。这种方法提高了作为非洲锥虫病抗疾病疫苗候选物的抗原的有效性。
