Moreau E, Bonsergent C, Al Dybiat I, Gonzalez L M, Lobo C A, Montero E, Malandrin L
Oniris, Ecole nationale vétérinaire, agroalimentaire et de l'alimentation Nantes-Atlantique, UMR Biologie, Epidémiologie et Analyse de Risque en santé animale, LUNAM Université, CS 40706, Nantes F-44307, France; UMR 1300 BioEpAR, INRA, Nantes F-44307, France.
Oniris, Ecole nationale vétérinaire, agroalimentaire et de l'alimentation Nantes-Atlantique, UMR Biologie, Epidémiologie et Analyse de Risque en santé animale, LUNAM Université, CS 40706, Nantes F-44307, France; UMR 1300 BioEpAR, INRA, Nantes F-44307, France.
Exp Parasitol. 2015 Aug;155:40-5. doi: 10.1016/j.exppara.2015.04.024. Epub 2015 May 5.
Babesiosis is an important veterinary and zoonotic tick borne disease caused by the hemoprotozoan Babesia spp. which infects red blood cell of its vertebrate host. In order to control the infection, vaccination that targets molecules involved in the invasion process of red blood cells could provide a good alternative to chemotherapy. Among these molecules, Apical Membrane Antigen-1 (AMA-1) has been described as an excellent vaccine candidate in Plasmodium spp. In this paper, we have investigated AMA-1 of Babesia divergens (BdAMA-1) as vaccine candidate by evaluating its polymorphism and by studying the humoral response against BdAMA-1 of sheep experimentally infected with B. divergens. Polymorphism of BdAMA-1 was investigated by sequencing the corresponding gene of 9 B. divergens isolates from different geographical areas in France. Two Bdama-1 haplotypes (A and B) could be defined based on 2 non-synonymous point mutations. In silico prediction of linear epitopes revealed that the antigenicity of the 2 haplotypes is very similar. Antibody production against the extracellular domain of BdAMA-1 is weak and late, between 1 and 5 months after the inoculation of parasites. Both IgG1 and IgG2 are components of the anti-BdAMA-1 response. These results indicate that while BdAMA-1 may not be an immuno-dominant antigen, it could induce a mixed type 1 and type 2 immune response. In light of these results, the potential of BdAMA-1 as vaccine candidate is discussed.
巴贝斯虫病是一种重要的兽医疾病和人兽共患蜱传疾病，由血液原生动物巴贝斯虫属引起，该属会感染其脊椎动物宿主的红细胞。为了控制感染，针对参与红细胞入侵过程的分子进行疫苗接种可能是化疗的一个很好的替代方案。在这些分子中，顶端膜抗原-1（AMA-1）在疟原虫属中已被描述为一种优秀的疫苗候选物。在本文中，我们通过评估其多态性并研究实验感染分歧巴贝斯虫的绵羊对BdAMA-1的体液反应，来研究分歧巴贝斯虫的AMA-1（BdAMA-1）作为疫苗候选物的情况。通过对来自法国不同地理区域的9株分歧巴贝斯虫分离株的相应基因进行测序，研究了BdAMA-1的多态性。基于2个非同义点突变可定义出2种Bdama-1单倍型（A和B）。线性表位的计算机预测显示，这2种单倍型的抗原性非常相似。接种寄生虫后1至5个月之间，针对BdAMA-1细胞外结构域的抗体产生较弱且较晚。IgG1和IgG2都是抗BdAMA-1反应的组成部分。这些结果表明，虽然BdAMA-1可能不是免疫优势抗原，但它可以诱导1型和2型混合免疫反应。鉴于这些结果，讨论了BdAMA-1作为疫苗候选物的潜力。
