Lin Zhenhua, Yemelyanova Anna V, Gambhira Ratish, Jagu Subhashini, Meyers Craig, Kirnbauer Reinhard, Ronnett Brigitte M, Gravitt Patti E, Roden Richard B S
Department of Pathology, Johns Hopkins University Medical Institutions, Baltimore, Maryland, USA.
Am J Pathol. 2009 Jan;174(1):136-43. doi: 10.2353/ajpath.2009.080588. Epub 2008 Dec 18.
The expression pattern of human papillomavirus (HPV) capsid antigen L2 is poorly described, and the significance of its localization with both promyelocytic leukemia protein (PML) and Daxx in a subnuclear domain, nuclear domain 10 (ND-10), when ectopically expressed in tissue culture cells is controversial. To address whether ND-10 localization of L2 occurs in natural cervical lesions, we used a HPV16 and HPV18 L2-specific monoclonal antibody (RG-1), in addition to rabbit antiserum to HPV6 L2, to localize L2. Immunohistochemical staining with RG-1 produced diffuse staining in the nuclei of some cells located within the superficial epithelial layers in eight of nine cases of HPV16/18(+) cervical intraepithelial neoplasia grade 1 (CIN1); however, no staining was observed in HPV16/18(+) high-grade CIN (0 of 8 cases), normal cervical epithelium (0 of 20 cases), cervical squamous cell carcinoma (0 of 102 cases), adenocarcinoma (0 of 51 cases), or adenosquamous carcinoma (0 of 6 cases). HPV16/18(+) cervical lesions that express L2 exhibit higher HPV16/18 genome copies per cell compared with those that do not positively stain with RG-1 (P = 0.04). RG-1 staining of HeLa cells transfected with L2 expression constructs was frequently concentrated in the ND-10, particularly in cells expressing high levels of L2, and co-localized with the cellular markers of ND-10, PML, and Daxx. In contrast, L2 was primarily diffuse within the nucleus and distinct from ND-10 as defined by PML immunofluorescent staining in CIN lesions, condylomata, and HPV16-transduced organotypic cultures.
人乳头瘤病毒（HPV）衣壳抗原L2的表达模式鲜有描述，当在组织培养细胞中异位表达时，其在核仁结构域10（ND - 10）中与早幼粒细胞白血病蛋白（PML）和Daxx共定位的意义存在争议。为了探究L2在天然宫颈病变中是否会定位于ND - 10，我们使用了HPV16和HPV18 L2特异性单克隆抗体（RG - 1），以及针对HPV6 L2的兔抗血清来定位L2。在9例HPV16/18（+）的宫颈上皮内瘤变1级（CIN1）病例中，8例的浅表上皮层内部分细胞的细胞核经RG - 1免疫组化染色后呈弥漫性染色；然而，在HPV16/18（+）的高级别CIN（8例均无染色）、正常宫颈上皮（20例均无染色）、宫颈鳞状细胞癌（102例均无染色）、腺癌（51例均无染色）或腺鳞癌（6例均无染色）中均未观察到染色。与未被RG - 1阳性染色的HPV16/18（+）宫颈病变相比，表达L2的HPV16/18（+）宫颈病变每个细胞的HPV16/18基因组拷贝数更高（P = 0.04）。用L2表达构建体转染的HeLa细胞经RG - 1染色后，荧光信号常集中在ND - 10，尤其是在高表达L2的细胞中，并且与ND - 10的细胞标志物PML和Daxx共定位。相比之下，在CIN病变、尖锐湿疣和HPV16转导的器官型培养物中，根据PML免疫荧光染色定义，L2主要在细胞核内呈弥漫性分布，与ND - 10不同。
