Koch H T, Ocama J G, Munatswa F C, Byrom B, Norval R A, Spooner P R, Conrad P A, Irvin A D
Veterinary Research Laboratory, Causeway, Zimbabwe.
Vet Parasitol. 1988 Apr;28(1-2):19-32. doi: 10.1016/0304-4017(88)90015-5.
Theilerial parasites of cattle were isolated by a variety of methods from the Harare area of Zimbabwe. Parasite stocks were established in lymphoid cell cultures and as cryopreserved sporozoite stabilates in the laboratory. Fourteen stocks in culture were characterized by testing them with monoclonal antibodies (MAb) raised against T. parva parva and T. parva lawrencei antigen. Two of these stocks had profiles similar to T. taurotragi isolates from East Africa, the other stocks had profiles similar to T. parva parva, however, many of them failed to bind MAb No. 7, and this may be a distinctive feature for T. parva bovis. Three T. p. bovis stocks were titrated by injecting different doses of the respective stabilates into pairs of cattle. Reactions ranged from severe to inapparent according to the stocks and dose used, but no fatal reactions were recorded, even at the highest dose rate. On recovery, all cattle were given homologous and then heterologous challenge. The results of the latter challenge showed that the Boleni stock gave good cross-protection against challenge with two other Zimbabwean stocks. This stock may therefore be a candidate for immunizing cattle, under field conditions, to protect them against T. p. bovis in Zimbabwe. Non-pathogenic strains of T. p. bovis may be difficult to distinguish from T. taurotragi unless cross-challenge experiments can be conducted and/or MAb profiles have been made. An improved serological test is needed to differentiate antibodies to these parasites in the sera of recovered cattle.
通过多种方法从津巴布韦哈拉雷地区分离出牛泰勒虫寄生虫。在实验室的淋巴细胞培养物中建立了寄生虫株，并将其作为冷冻保存的子孢子稳定株。通过用针对小泰勒虫和劳伦斯泰勒虫抗原产生的单克隆抗体（MAb）对培养的14个株系进行检测来进行特征鉴定。其中两个株系的图谱与来自东非的转角泰勒虫分离株相似，其他株系的图谱与小泰勒虫相似，然而，它们中的许多未能与7号单克隆抗体结合，这可能是牛泰勒虫的一个独特特征。通过向成对的牛注射不同剂量的各自稳定株对三个牛泰勒虫株系进行滴定。根据所用的株系和剂量，反应范围从严重到不明显，但即使在最高剂量率下也没有记录到致命反应。恢复后，所有牛都接受了同源然后异源攻击。后者攻击的结果表明，博莱尼株系对用其他两个津巴布韦株系进行的攻击提供了良好的交叉保护。因此，该株系可能是在野外条件下免疫牛以保护它们免受津巴布韦牛泰勒虫感染的候选株系。除非能够进行交叉攻击实验和/或制作单克隆抗体图谱，否则牛泰勒虫的非致病株系可能很难与转角泰勒虫区分开来。需要一种改进的血清学检测方法来区分康复牛血清中针对这些寄生虫的抗体。
