紫外线B照射对人表皮角质形成细胞内源性逆转录病毒序列的转录激活作用。

Transcriptional activation of endogenous retroviral sequences in human epidermal keratinocytes by UVB irradiation.

作者信息

Hohenadl C, Germaier H, Walchner M, Hagenhofer M, Herrmann M, Stürzl M, Kind P, Hehlmann R, Erfle V, Leib-Mösch C

机构信息

Medical Clinic III, Faculty of Clinical Medicine Mannheim, University of Heidelberg, Germany.

出版信息

J Invest Dermatol. 1999 Oct;113(4):587-94. doi: 10.1046/j.1523-1747.1999.00728.x.

DOI:10.1046/j.1523-1747.1999.00728.x

PMID:10504445

Abstract

Ultraviolet radiation is a pathogenic factor in various diseases, e. g., autoimmune disorders such as lupus erythematosus. On the other hand, endogenous retroviruses are discussed as etiologic agents in lupus erythematosus. Therefore, we investigated the influence of ultraviolet irradiation on expression of human endogenous retroviral sequences and human endogenous retroviral sequence promoter-driven transcription of cellular genes using human epidermal keratinocytes as a model system. First, conserved sequences of endogenous retroviral pol genes were amplified from cellular mRNA by reverse transcriptase polymerase chain reaction with degenerate oligonucleotide primers. Polymerase chain reaction products were hybridized in a reverse dot blot hybridization assay to a representative number of distinct cloned human endogenous retroviral pol fragments. Using this method, we could show that irradiation with 30 mJ per cm2 ultraviolet B activates transcription of various endogenous retroviral pol sequences in primary epidermal keratinocytes as well as in a spontaneously immortalized keratinocyte cell line (HaCaT). Interestingly, some of these sequences were found to be closely related to pol sequences of human endogenous retroviral sequences which have been shown to be expressed in autoimmune patients. Analysis of human endogenous retroviral pol expression in vivo using skin biopsies of lupus erythematosus patients revealed similar activation patterns. In a second approach, ultraviolet B- induced chimeric transcripts were isolated which are initiated by human endogenous retroviral promoters and proceed into cellular sequences using a newly established modified differential display polymerase chain reaction technique. The activation of human endogenous retroviral sequence transcription by ultraviolet B may contribute to the pathogenesis of lupus erythematosus, where inappropriate antigenic presentation of ultraviolet B-induced viral and cellular proteins could stimulate autoantibody production.

摘要

紫外线辐射是多种疾病的致病因素，例如自身免疫性疾病，如红斑狼疮。另一方面，内源性逆转录病毒被认为是红斑狼疮的病因。因此，我们以人表皮角质形成细胞为模型系统，研究了紫外线照射对人内源性逆转录病毒序列表达以及人内源性逆转录病毒序列启动子驱动的细胞基因转录的影响。首先，使用简并寡核苷酸引物通过逆转录聚合酶链反应从细胞mRNA中扩增内源性逆转录病毒pol基因的保守序列。聚合酶链反应产物在反向点杂交试验中与大量不同的克隆人内源性逆转录病毒pol片段杂交。使用这种方法，我们可以证明，每平方厘米30毫焦的紫外线B照射可激活原代表皮角质形成细胞以及自发永生化角质形成细胞系（HaCaT）中各种内源性逆转录病毒pol序列的转录。有趣的是，发现其中一些序列与已证实在自身免疫患者中表达的人内源性逆转录病毒序列的pol序列密切相关。使用红斑狼疮患者的皮肤活检组织分析体内人内源性逆转录病毒pol的表达，发现了类似的激活模式。在第二种方法中，使用新建立的改良差异显示聚合酶链反应技术分离了由人内源性逆转录病毒启动子启动并进入细胞序列的紫外线B诱导的嵌合转录本。紫外线B对内源性逆转录病毒序列转录的激活可能有助于红斑狼疮的发病机制，其中紫外线B诱导的病毒和细胞蛋白的不适当抗原呈递可能刺激自身抗体的产生。