Centre for Geographic Medicine Research - Coast, Kenya Medical Research Institute (KEMRI), P.O. Box 230-80108, Kilifi, Kenya.
Laboratory Bacteriology Research, Faculty of Medicine and Health Sciences, Ghent University, De Pintelaan, 185 9000, Ghent, Belgium.
Parasit Vectors. 2017 Oct 30;10(1):537. doi: 10.1186/s13071-017-2496-7.
The protozoan parasite Trichomonas vaginalis is the most common non-viral, sexually transmitted pathogen. Although T. vaginalis is highly prevalent among women in Kenya, there is lack of data regarding genetic diversity of isolates currently in circulation in Kenya.
Typing was performed on 22 clinical isolates of T. vaginalis collected from women attending the antenatal care clinic at Kilifi County Hospital, Kenya, in 2015. Genotyping followed a previously proposed restriction fragment length polymorphism (RFLP) scheme, which involved in silico cleavage of the amplified actin gene by HindII, MseI and RsaI restriction enzymes. Phylogenetic analysis of all the sequences was performed to confirm the results obtained by RFLP-analysis and to assess the diversity within the RFLP genotypes. Additionally, we determined carriage of the four different types of Trichomonas vaginalis viruses (TVVs) by polymerase chain reaction.
In silico RFLP-analysis revealed five actin genotypes; 50.0% of the isolates were of actin genotype E, 27.3% of actin genotype N, 13.6% of actin genotype G and 4.5% of actin genotypes I and P. Phylogenetic analysis was in agreement with the RFLP-analysis, with the different actin genotypes clustering together. Prevalence of TVVs was 43.5% (95% confidence interval, CI: 23.2-65.5). TVV1 was the most prevalent, present in 39.1% of the strains and 90% of the T. vaginalis isolates which harbored TVVs had more than one type of TVV. None of the isolates of actin genotype E harbored any TVV.
The presence of five actin genotypes in our study suggests notable diversity among T. vaginalis isolates occurring among pregnant women in Kilifi, Kenya. Isolates of the most prevalent actin genotype E lacked TVVs. We found no association between T. vaginalis genotype, carriage of TVVs and symptoms. Further studies with higher number of strains should be conducted in order to corroborate these results.
原生动物寄生虫阴道毛滴虫是最常见的非病毒性性传播病原体。尽管阴道毛滴虫在肯尼亚的女性中非常普遍，但目前肯尼亚流行的分离株的遗传多样性数据缺乏。
对 2015 年在肯尼亚基利菲县医院产前保健诊所就诊的 22 例阴道毛滴虫临床分离株进行了分型。基因分型采用先前提出的限制片段长度多态性（RFLP）方案，该方案涉及通过 HindII、MseI 和 RsaI 内切酶对扩增的肌动蛋白基因进行计算机切割。对所有序列进行系统发育分析，以确认 RFLP 分析的结果，并评估 RFLP 基因型内的多样性。此外，我们还通过聚合酶链反应确定了四种不同类型的阴道毛滴虫病毒（TVV）的携带情况。
计算机 RFLP 分析显示有 5 种肌动蛋白基因型；50.0%的分离株为肌动蛋白基因型 E，27.3%为肌动蛋白基因型 N，13.6%为肌动蛋白基因型 G，4.5%为肌动蛋白基因型 I 和 P。系统发育分析与 RFLP 分析一致，不同的肌动蛋白基因型聚集在一起。TVV 的流行率为 43.5%（95%置信区间，CI：23.2-65.5）。TVV1 最为流行，存在于 39.1%的菌株中，90%携带 TVV 的阴道毛滴虫分离株携带一种以上类型的 TVV。没有一个肌动蛋白基因型 E 的分离株携带任何 TVV。
本研究中发现的 5 种肌动蛋白基因型表明，肯尼亚基利菲孕妇中阴道毛滴虫分离株存在显著的多样性。最常见的肌动蛋白基因型 E 的分离株缺乏 TVV。我们没有发现阴道毛滴虫基因型、TVV 携带情况和症状之间存在任何关联。应该进行更多菌株的进一步研究来证实这些结果。
