Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, Prédio 43421, Campus do Vale, Caixa Postal 15005, Porto Alegre, RS 91501-970, Brazil.
Vaccine. 2012 Nov 6;30(48):6912-7. doi: 10.1016/j.vaccine.2012.08.078. Epub 2012 Sep 13.
The tick Rhipicephalus (Boophilus) microplus is a blood-sucking ectoparasite of cattle that severely impairs livestock production. Studies on tick immunological control address mostly single-antigen vaccines. However, from the commercial standpoint, so far no single-antigen vaccine has afforded appropriate protection against all R. microplus populations. In this context, multi-antigen cocktails have emerged as a way to enhance vaccine efficacy. In this work, a multi-antigenic vaccine against R. microplus was analyzed under field conditions in naturally infested cattle. The vaccine was composed by three tick recombinant proteins from two tick species that in previous single-vaccination reports provided partial protection of confined cattle against R. microplus infestations: vitellin-degrading cysteine endopeptidase (VTDCE) and boophilus yolk pro-cathepsin (BYC) from R. microplus, and glutathione S-transferase from Haemaphysalis longicornis (GST-Hl). Increased antibody levels against three proteins were recorded after immunizations, with a distinct humoral immune response dynamics for each protein. Compared to the control group, a statistically significant lower number of semi-engorged female ticks were observed in vaccinated cattle after two inoculations. This reduction persisted for 3 months, ranging from 35.3 to 61.6%. Furthermore, cattle body weight gain was significantly higher in vaccinated animals when compared to control cattle. Compared to the single-antigen vaccines composed by VTDCE, BYC or GST-Hl, this three-antigen vaccine afforded higher protection levels against R. microplus infestations.
微小牛蜱（Boophilus）是一种吸血的体外寄生虫，严重损害了家畜的生产。关于蜱免疫控制的研究主要针对单抗原疫苗。然而，从商业角度来看，到目前为止，还没有一种单抗原疫苗能为所有微小牛蜱种群提供适当的保护。在这种情况下，多抗原鸡尾酒已成为提高疫苗效力的一种方法。在这项工作中，对一种针对微小牛蜱的多抗原疫苗在自然感染的牛中进行了田间条件下的分析。该疫苗由来自两种蜱的三种蜱重组蛋白组成，在之前的单一疫苗接种报告中，这三种蛋白为圈养牛提供了对微小牛蜱感染的部分保护：微小牛蜱的卵黄降解半胱氨酸内肽酶（VTDCE）和 Boophilus 卵黄前半胱氨酸酶（BYC），以及长角血蜱的谷胱甘肽 S-转移酶（GST-Hl）。免疫接种后，记录到针对三种蛋白的抗体水平升高，每种蛋白的体液免疫反应动态明显不同。与对照组相比，在两次接种后，接种疫苗的牛中观察到的半饱雌性蜱数量明显减少。这种减少持续了 3 个月，范围从 35.3%到 61.6%。此外，与对照组相比，接种疫苗的动物的体重增加明显更高。与由 VTDCE、BYC 或 GST-Hl 组成的单抗原疫苗相比，这种三抗原疫苗对微小牛蜱感染提供了更高的保护水平。
