Smidt I, Kiiker R, Oopkaup H, Lapp E, Rööp T, Truusalu K, Štšepetova J, Truu J, Mändar R
1 Department of Microbiology, Faculty of Medicine, University of Tartu, Ravila 19, Tartu 50411, Estonia.
2 Competence Centre on Health Technologies, Tiigi 61b, Tartu 50410, Estonia.
Benef Microbes. 2015;6(5):747-51. doi: 10.3920/BM2014.0154. Epub 2015 Apr 22.
Vaginal lactobacilli offer protection against microbiota imbalance and genitourinary tract infections. We compared vaginal lactobacilli in 50 Estonian women of child-bearing age applying culture-based methods, quantitative PCR and next-generation sequencing (NGS). The culture-based methods found three different lactobacilli: Lactobacillus crispatus, Lactobacillus jensenii and Lactobacillus gasseri. Using NGS revealed the presence of L. crispatus in 76%, Lactobacillus iners in 52%, L. jensenii in 47% and L. gasseri in 33% of the samples. According to qPCR, L. iners was present in 67% and L. crispatus in 64% of the samples. The proportions of L. crispatus revealed by qPCR and NGS were in good correlation (R=0.79, P<0.001), while that of L. iners correlated poorly (R=0.13, P>0.05). Good concordance for L. crispatus was also found between the results of the culture-based method and qPCR. Finally, good overlap between the results of the culture-based method and NGS was revealed: in case of a positive NGS result for L. crispatus, the same species was isolated in 95% of samples. The corresponding percentages were 82% for L. jensenii and 86% for L. gasseri. Our data indicate fairly general concordance of the three methods for detecting vaginal lactobacilli, except for L. iners. This points out the importance of standardisation of techniques, and the respective studies should involve cultures applying a medium suitable for the fastidious L. iners.
阴道乳酸杆菌可预防微生物群失衡和泌尿生殖道感染。我们运用基于培养的方法、定量PCR和下一代测序（NGS），对50名爱沙尼亚育龄妇女的阴道乳酸杆菌进行了比较。基于培养的方法发现了三种不同的乳酸杆菌：卷曲乳酸杆菌、詹氏乳酸杆菌和加氏乳酸杆菌。使用NGS检测发现，76%的样本中存在卷曲乳酸杆菌，52%存在惰性乳酸杆菌，47%存在詹氏乳酸杆菌，33%存在加氏乳酸杆菌。根据定量PCR检测，67%的样本中存在惰性乳酸杆菌，64%存在卷曲乳酸杆菌。定量PCR和NGS检测出的卷曲乳酸杆菌比例具有良好的相关性（R=0.79，P<0.001），而惰性乳酸杆菌的相关性较差（R=0.13，P>0.05）。基于培养的方法和定量PCR检测卷曲乳酸杆菌的结果也具有良好的一致性。最后，基于培养的方法和NGS的结果显示出良好的重叠性：在卷曲乳酸杆菌NGS检测结果为阳性的情况下，95%的样本中分离出了相同的菌种。詹氏乳酸杆菌和加氏乳酸杆菌的相应百分比分别为82%和86%。我们的数据表明，除了惰性乳酸杆菌外，三种检测阴道乳酸杆菌的方法具有相当普遍的一致性。这指出了技术标准化的重要性，并且相关研究应采用适合苛求的惰性乳酸杆菌生长的培养基进行培养。
