Nishio H, Matsui K, Tsuji H, Tamura A, Suzuki K
Osaka Medical College, Department of Legal Medicine, Takatsuki, Japan.
J Anat. 2001 May;198(Pt 5):581-9. doi: 10.1046/j.1469-7580.2001.19850581.x.
The janus kinases (JAK) and signal transducers and activators of the transcription (STAT) pathway have been shown to be activated by a number of cytokines or growth factors and to play significant roles in the differentiation of various cell types. In the present study, we investigated the distribution of the JAK-STAT pathway using immunohistochemistry in the human epidermis. Each element of the pathway showed abundant and differential expression in the epidermis. The differential distribution of the elements was most strikingly observed in the horny keratinised cell and granular layers of the epidermis. JAK2, JAK3, STAT1 and STAT5 were expressed in high amounts, and JAK1, TYK2, STAT2, STAT3, STAT4 and STAT6 to a much lesser extent in the horny cell layer. JAK3, TYK2, STAT2, STAT3, STAT4 and STAT6 were more abundantly expressed in the granular layer than the lower layers of the epidermis. JAK1, STAT1 and STAT5 were expressed at almost the same levels in the various layers of the epidermis. These results show that elements of the JAK-STAT pathway are abundantly and differentially expressed in the epidermis. It is suggested that each element of the pathway may play a role at a distinct stage of keratinocyte differentiation.
研究表明， Janus激酶（JAK）和信号转导及转录激活因子（STAT）通路可被多种细胞因子或生长因子激活，并在多种细胞类型的分化中发挥重要作用。在本研究中，我们采用免疫组织化学方法研究了JAK-STAT通路在人表皮中的分布情况。该通路的各个成分在表皮中均有丰富且差异表达。在角质化细胞和表皮颗粒层中，各成分的差异分布最为明显。JAK2、JAK3、STAT1和STAT5在角质化细胞层中大量表达，而JAK1、TYK2、STAT2、STAT3、STAT4和STAT6的表达量则少得多。JAK3、TYK2、STAT2、STAT3、STAT4和STAT6在颗粒层中的表达比表皮下层更为丰富。JAK1、STAT1和STAT5在表皮各层中的表达水平几乎相同。这些结果表明，JAK-STAT通路的成分在表皮中大量且差异表达。提示该通路的每个成分可能在角质形成细胞分化的不同阶段发挥作用。
