| 摘要: |
| ［摘要］ 目的 比较来自中国、日本和巴西的142株新型隐球菌格鲁比变种的多位点微卫星分型（MLMT）特征。方法 选择新型隐球菌格鲁比变种株142株，其中采集自中国40株，日本13株，巴西89株；有73株（中国30株，日本7株，巴西36株）从临床患者标本中分离获得，另69株（中国10株，日本6株，巴西53株）从环境物（鸽粪）标本中分离获得。所有研究菌株均由日本千叶大学医学真菌研究中心提供。提取菌株DNA，对微卫星位点CNG1（TA）、CNG2（GA）、CNG3（CAT）进行扩增和测序，通过Chromas软件计算基序重复数以确定基因型，并基于辛普森指数（D）评估基因型多样性。结果 142株菌株共有17种MLMT基因型（中国菌株检出6种，日本菌株检出2种，巴西菌株检出13种）。以MLMT-17型占比最高（38.03%，54/142），在三个国家的临床和环境标本中均有检出。MLMT-2型和MLMT-34型在三个国家均有检出。中国、日本和巴西三个国家菌株的辛普森指数（D）分别为0.32、0.15和0.82，巴西菌株的基因型多样性较中国（χ2=76.521，P<0.001）和日本（Fisher确切概率法，P<0.001）更高，而中国和日本菌株的基因型多样性比较差异无统计学意义（Fisher确切概率法，P=0.287）。按标本来源进行分层比较，环境菌株的基因型多样性显著高于临床菌株［辛普森指数（D）：0.68 vs 0.76； χ2=54.810，P<0.001］。结论 新型隐球菌格鲁比变种的基因型构成可能存在地域差异。中国和日本以MLMT-17型为主，巴西以MLMT-36型为主，且巴西基因型多样性更高。 |
| 关键词: 新型隐球菌格鲁比变种 多位点微卫星分型 基因型多样性 |
| DOI：10.3969/j.issn.1674-3806.2026.05.13 |
| 分类号:R 379 |
| 基金项目:贵州省卫生健康委员会科学技术基金项目（编号：gzwkj2013-1-055） |
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| Comparison of multilocus microsatellite typing of 142 Cryptococcus neoformans var. grubii strains from three countries |
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LU Qin1, ZHU Jian2, SHI Rongxing1, HE Tingting1, ZHANG Wei3
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1.Clinical Medical College, Guizhou Medical University, Guiyang 550004, China; 2.Department of Gastroenterology, Guiyang Second People′s Hospital & Jinyang Hospital Affiliated to Guizhou Medical University, Guiyang 550081, China; 3.Department of Gastroenterology, the Affiliated Hospital of Guizhou Medical University & the First Affiliated Hospital of Sun Yat-sen University, Guizhou Hospital, Guiyang 550004, China
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| Abstract: |
| ［Abstract］ Objective To compare multilocus microsatellite typing(MLMT) characteristics of 142 Cryptococcus neoformans var. grubii strains isolated from China, Japan, and Brazil. Methods A total of 142 isolated strains of Cryptococcus neoformans var. grubii were selected, including 40 strains from China, 13 strains from Japan, and 89 strains from Brazil. In the 142 isolated strains, 73 strains(30 strains from China, 7 strains from Japan and 36 strains from Brazil) were isolated from clinical patient specimens, and the other 69 strains(10 strains from China, 6 strains from Japan, 53 strains from Brazil) were isolated from environmental samples(pigeon droppings). All the strains were provided by Medical Mycology Research Center, Chiba University, Japan. Strain DNAs were extracted, and the microsatellite loci CNG1(TA), CNG2(GA), and CNG3(CAT) were amplified and sequenced. Genotypes were determined by counting motif repeats using Chromas software, and genotype diversity was assessed based on the Simpson′s index(D). Results In the 142 strains, 17 MLMT genotypes were identified. Six MLMT genotypes were identified in the strains from China, 2 MLMT genotypes in the strains from Japan, and 13 MLMT genotypes in the strains from Brazil. The MLMT-17 genotype was the most prevalent(38.03%, 54/142) and was identified in both clinical and environmental specimens in the three countries. In addition, the MLMT-2 genotype and the MLMT-34 genotype had been identified in the three countries. The Simpson′s index(D) of the strains was 0.32, 0.15, and 0.82 for China, Japan and Brazil, respectively, with the strains in Brazil exhibiting higher genotype diversity than those in China(χ2=76.521, P<0.001) and Japan(Fisher′s exact test, P<0.001). However, the comparison of the genetic diversity of the strains between China and Japan showed no statistically significant difference(Fisher′s exact test, P=0.287). Stratified comparison by sample origin revealed that the genotypic diversity in environmental isolates was significantly higher than that in clinical isolates［Simpson′s index(D): 0.68 vs 0.76; χ2=54.810, P<0.001］. Conclusion The genotype composition of Cryptococcus neoformans var. grubii strains varies by region. In China and Japan, the MLMT-17 genotype is predominant, while in Brazil, the MLMT-36 genotype is predominant, and the genotype diversity in Brazil is the highest. |
| Key words: Cryptococcus neoformans var. grubii Multilocus microsatellite typing(MLMT) Genotype diversity |
