ABSTRACT

Background: Candida species have long been recognised as aetiological agents of opportunistic infections of the oral mucosa, and more recently, as players of polymicrobial interactions driving caries, periodontitis and oral carcinogenesis.

Methods: We studied the clonal structure of Candida spp. at oral niche resolution in patients (n = 20) with a range of oral health profiles over 22 months. Colonies from oral micro-environments were examined with multilocus sequencing typing.

Results: Candida spp. identified were C. albicans, C. glabrata and C. dubliniensis. Increased propensity for micro-variations giving rise to multiple diploid strain types (DST), as a result of loss of heterozygosity, was observed among C. albicans clade 1 isolates compared to other clades. Micro-variations among isolates were also observed in C. dubliniensis contra to expectations of stable population structures for this species. Multiple sequence types were retrieved from patients without clinical evidence of oral candidosis, while single sequence types were isolated from oral candidosis patients.

Conclusion: This is the first study to describe the clonal population structure, persistence and stability of Candida spp. at oral niche level. Future research investigating links between Candida spp. clonality and oral disease should recognise the propensity to micro-variations amongst oral niches in C. albicans and C. dubliniensis identified here.

摘要

背景：长期以来， 念珠菌一直被认为是口腔黏膜机会性感染的病原体，最近被认为是多种微生物相互作用驱动龋齿、牙周炎和口腔癌发生的因素。

方法：我们研究了念珠菌属的克隆结构。在 22 个月内具有一系列口腔健康状况的患者 (n = 20) 的口腔生态位消退。使用多位点测序分型检查来自口腔微环境的菌落。

结果： 念珠菌属。鉴定出白色念珠菌、光滑念珠菌和都柏林念珠菌。与其他进化枝相比，在白色念珠菌进化枝 1 分离株中观察到，由于杂合性丧失，导致产生多种二倍体菌株类型 (DST) 的微变异倾向增加。在C. dubliniensis中也观察到分离株之间的微变化，这与对该物种稳定种群结构的预期相反。从没有口腔念珠菌病临床证据的患者中检索到多个序列类型，而从口腔念珠菌病患者中分离出单一序列类型。

结论：这是第一项描述念珠菌属的克隆群体结构、持久性和稳定性的研究。在口头利基水平。未来研究调查念珠菌属之间的联系。克隆性和口腔疾病应认识到此处确定的白色念珠菌和都柏林念珠菌口腔生态位的微变异倾向。