三氮脒药物治疗对吉氏巴贝斯虫线粒体Cyt b基因的影响调查

Influence of diminazene aceturate treatment on the cytochrome b gene of canine Babesia gibsoni

旨在检测患病犬经三氮脒治疗后,吉氏巴贝斯虫线粒体细胞色素b(Cyt b)是否存在基因突变。调查了2010至2020年犬巴贝斯虫病的流行情况,收集了11份自然感染吉氏巴贝斯虫且接受三氮脒治疗的患犬血液样品,采用蛋白酶K消化,苯酚提取法提取血液中基因组DNA,设计引物,通过PCR扩增吉氏巴贝斯虫Cyt b基因片段并进行测序分析。调查发现,自2010年以来,通过三氮脒治疗的吉氏巴贝斯虫病的疗程逐渐延长,复发率也逐渐增加。在11份血样中,吉氏巴贝斯虫的Cyt b基因彼此之间相似性高达99.65%~100%,与日本分离株也有较高的同源性(99.18%~99.54%)。在Cyt b基因nt363基因位点上没有发现基因突变。这些结果说明虽然吉氏巴贝斯虫对三氮脒逐渐产生耐药,但三氮脒对吉氏巴贝斯虫Cyt b基因并不产生影响。

In order to detect mutation of the cytochrome b gene of B. gibsoni strains which had been treated with diminazene aceturate, this test investigated the cases of canine Babesia gibsoni infection in the period from 2010 to 2020. Eleven blood samples from dogs which had been infected with B. gibsoni naturally and treated with diminazene aceturate were collected. Genomic DNA was extracted from the blood samples using the proteinase K and phenol extraction technique. The results showed that the recuperation time in dogs infected with B. gibsoni and treated with diminazene aceturate had been gradually longer since 2010. And the rate of recurrence was also higher than before. The results of the experiment showed that the sequences of the B. gibsoni Cyt b gene were similar with each other(99.65%-100%) and were of high homology to the isolated Japanese strain of B. gibsoni(99.18%-99.54%). Besides, there was no substitution of methionine with isoleucine at the 363 genetic locus. Therefore, all these results indicated that although Babesia gibsoni had developed resistance to diminazene aceturate, since 2010, there was as yet no mutation of the Cyt b gene of B. gibsoni.