Molecular epidemiology of human herpes virus 8-relafed diseases in Japan and Asia

为了阐明日本和亚洲人类疱疹病毒8型(HHV8)相关疾病的分子流行病学，我们调查了Kaposi肉瘤(KS)、多中心Castleman病(MCTD)和淋巴瘤组织中HHV8及其亚型的频率。我们请求台湾、韩国和泰国的病理学系合作；2000年我们访问了台湾的国立台湾大学和国立成功大学，2001年访问了韩国的首尔国立大学、峨山医学中心和Keimyung大学，2002年分别访问了泰国的清迈大学和Mahidol大学。本研究用福尔马林固定石蜡包埋的组织切片，包括台湾的19例KS，韩国的10例KS，9例MCTD和淋巴瘤。对于日本的组织，我们检查了东京都Komagome医院的12例KS和140例淋巴瘤。对提取的DNA进行HHV8-ORF26套式、K-1VR1-PCR和ORF75-PCR扩增，对扩增产物进行测序分析，发现台湾地区19例KS中有18例(95%)、10例韩国KS中有6例(60%)、4例韩国MCTD中有4例(44%)阳性，而韩国淋巴瘤中无一例阳性。另一方面，21例日本KS中有21例(100%)和140例日本淋巴瘤中有14例(10%)检测到HHV8-ORF26在台湾和韩国以C型为主，在日本以A型为主，提示HHV8在日本的传播具有特殊性。ORF26和K1-VR1系统的HHV8亚型基本一致，但在每个样本中有几个病例显示不同的亚型。ORF75亚型与ORF26亚型的比较也证实了日本部分KS基因重组的证据。因此，频繁的重组表明HHV8在一个相对较小的群体中传播。

To clarify the molecular epidemiology of human herpes virus 8 (HHV8)-related diseases in Japan and Asia, we investigated the frequency of HHV8 and Its subtypes in the tissues of Kaposi sarcoma (KS), multicentric Castleman's disease (MCTD), and lymphomas. We asked cooperation to the Departments of Pathology, in Taiwan, Korea and Thailand; we visited National Taiwan University and National Cheng Kung University in Taiwan in 2000, Seoul National University, Asan Medical Center, and Keimyung University in Korea in 2001, and Chiang Mai University and Mahidol University in Thailand in 2002, respectively. The formalin-fixed and paraffin-embedded tissue sections, available for the study, were 19 cases of KS in Taiwan, and 10 cases of KS, 9 cases of MCTD, and 64 cases of lymphomas in Korea. For the tissues in Japan, we examined 12 cases of KS and 140 cases of lymphomasof Tokyo Metropolitan Komagome Hospital. The extracted DMA was subjected to the HHV8-ORF26 nested PCR, K-1VR1-PCR and ORF75-PCR, and then the amplicons were sequenced for the determination of subtypes.Positive PCR results were observed in 18 of 19 Taiwan KS (95%), 6 of 10 Korean KS (60%), 4 of Korean MCTD (44%) and none of 64 Korean lymphomas by HHV8-ORF26 nested PCR On the other hand, HHV8-ORF26 was observed in 21 of 21 Japanese KS (100%) and 14 of 140 Japanese lymphomas (10%).As for the subtypes of HHV8, according to the sequence polymorphism in ORF26 or K1-VR1, type C was predominant in Taiwan and Korea, whereas type A in Japan, suggesting the particular propagation of HHV8 in Japan.Sub-typing of HHV8 was nearly concordant between ORF26 and K1-VR1 systems, but there were several cases that showed different subtypes in each sample. The comparison of ORF75 subtype with ORF26 also demonstrated the evidence of recombination in some of Japanese KS. Thus frequent recombination suggests that HHV8 has propagated in a relatively small group.