Department of Mycology, Pasteur Institute of Iran, 1316943551 Tehran, Iran.
Department of Oral Medicine, School of Dentistry, Tehran University of Medical Sciences, Cancer Institute of Tehran, Imam Khomeini Hospital Complex, Tehran, Iran.
J Mycol Med. 2019 Dec;29(4):310-316. doi: 10.1016/j.mycmed.2019.100896. Epub 2019 Sep 11.
Multilocus sequence typing is a powerful method for genotyping of clinical isolates of Candidaalbicans. Cross-contamination between the patients is an important reason for nosocomial infections. Oropharyngeal candidiasis (OPC) caused by C. albicans is an important problem in patients with head and neck cancer, in Cancer Institute of Tehran. Here we studied the endemic genotypes of C. albicans isolates and the relationship between geographic distributions, potential cross-contaminations and the expression of SAP2 gene, an important gene in oral candidiasis, with MLST groups.
A total of 32 clinical strains of C. albicans isolated from head and neck cancer patients with oropharyngeal candidiasis were subjected to MLST analysis and SAP2 gene expression was analyzed by Real-time PCR.
We identified 75 polymorphic sites in 7 loci of C. albicans isolates and 30 diploid sequence types which 27 of them were found as new. After eBURST analysis, our results determined that CC 124 was the most prevalent group among all CCs. SAP2 gene showed high expression in almost all OPC patients' isolates, compared to the control.
We found few genetically-related as well as identical isolates among the 32 Candida strains which indicated low cross-contaminations among the patients. There was no relationship between C. albicans MLST profiles and their geographic distribution, cancer type and SAP2 gene expression. This lack of correlation was possibly due to the small understudy population; hence, finding more relevance requires studies with a higher number of samples.
多位点序列分型是一种用于鉴定临床分离的白色念珠菌基因型的强大方法。患者之间的交叉污染是医院感染的一个重要原因。白色念珠菌引起的口腔念珠菌病(OPC)是德黑兰癌症研究所头颈癌患者的一个重要问题。在这里,我们研究了白色念珠菌分离株的地方性基因型,以及地理分布、潜在交叉污染与 SAP2 基因表达之间的关系,SAP2 基因是口腔念珠菌病的一个重要基因。
对 32 例头颈癌伴口腔念珠菌病患者的白色念珠菌临床株进行 MLST 分析,并通过实时 PCR 分析 SAP2 基因表达。
我们在白色念珠菌分离株的 7 个基因座中鉴定出 75 个多态性位点和 30 个二倍体序列类型,其中 27 个为新发现的类型。eBURST 分析后,我们的结果表明 CC124 是所有 CC 中最常见的群体。与对照组相比,SAP2 基因在几乎所有 OPC 患者的分离株中均表现出高表达。
我们发现 32 株白色念珠菌中遗传上相关的以及相同的分离株很少,这表明患者之间的交叉污染较低。白色念珠菌 MLST 图谱与地理分布、癌症类型和 SAP2 基因表达之间没有关系。这种缺乏相关性可能是由于研究人群较小;因此,需要更多样本的研究来发现更多的相关性。