Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
Med Mycol. 2013 Apr;51(3):252-60. doi: 10.3109/13693786.2012.708883. Epub 2012 Aug 17.
Cryptococcosis is primarily caused by two Cryptococcus species, i.e., Cryptococcus neoformans and C. gattii. Both include several genetically diverse subgroups that can be differentiated using various molecular strain typing methods. Since little is known about the molecular epidemiology of the C. neoformans/C. gattii species complex in Japan, we conducted a molecular epidemiological analysis of 35 C. neoformans isolates from non-HIV patients in Nagasaki, Japan and 10 environmental isolates from Thailand. All were analyzed using URA5-restriction fragment length polymorphism (RFLP) and multilocus sequence typing (MLST). Combined sequence data for all isolates were evaluated with the neighbor-joining method. All were found to be serotype A and mating type MATα. Thirty-two of the 35 clinical isolates molecular type VNI, while the three remaining isolates were VNII as determined through the URA5-RFLP method. Thirty-one of the VNI isolates were identified as MLST sequence type (ST) 5, the remaining one was ST 32 and the three VNII isolates were found to be ST 43. All the environmental isolates were identified as molecular type VNI (four MLST ST 5 and six ST 4). Our study shows that C. neoformans isolates in Nagasaki are genetically homogeneous, with most of the isolates being ST 5.
隐球菌病主要由两种隐球菌引起，即新型隐球菌和格特隐球菌。这两种隐球菌都包括几个遗传上不同的亚群，可以通过各种分子菌株分型方法来区分。由于对日本新型隐球菌/格特隐球菌种复合体的分子流行病学知之甚少，我们对来自日本长崎的 35 株非 HIV 患者的新型隐球菌分离株和来自泰国的 10 株环境分离株进行了分子流行病学分析。所有分离株均采用 URA5 限制片段长度多态性（RFLP）和多位点序列分型（MLST）进行分析。所有分离株的联合序列数据均采用邻接法进行评估。所有分离株均为血清型 A 和交配型 MATα。35 株临床分离株中有 32 株为分子型 VNI，其余 3 株通过 URA5-RFLP 方法确定为 VNII。31 株 VNI 分离株鉴定为 MLST 序列型（ST）5，其余 1 株为 ST32，3 株 VNII 分离株为 ST43。所有环境分离株均鉴定为分子型 VNI（4 株 MLST ST5 和 6 株 ST4）。我们的研究表明，长崎的新型隐球菌分离株具有遗传同源性，大多数分离株为 ST5。
