Bissonnette R, Zeng H, McLean D I, Schreiber W E, Roscoe D L, Lui H
Division of Dermatology, University of British Columbia and Vancouver Hospital and Health Sciences Centre, Canada.
J Invest Dermatol. 1998 Oct;111(4):586-91. doi: 10.1046/j.1523-1747.1998.00345.x.
In evaluating the autofluorescence properties of normal and diseased skin we discovered that psoriatic plaques can emit a distinct red fluorescence when illuminated with UVA or blue light. Using a macrospectrofluorometer equipped with a 442 nm excitation laser, a sharp in vivo fluorescence emission peak around 635 nm could be demonstrated within the plaques of 34 of 75 (45%) patients with psoriasis. This peak was absent from normal appearing skin of psoriatic patients and also from the skin of 66 patients with other dermatologic diseases. A microspectrofluorometer coupled with the same excitation laser was used to obtain emission spectra of separated epidermal sheets and dermis from plaques demonstrating macroscopic red autofluorescence. An emission peak around 635 nm was observed in all three patients thus studied, but only on spectra obtained from the epidermis. Additional spectra of vertical microscopic sections of intact psoriatic skin from five other patients revealed that the peak originated from the stratum corneum. Emission spectra from other microlocations including the mid-epidermis and dermis of psoriatic and normal skin, as well as the stratum corneum of normal skin, failed to demonstrate a 635 nm peak. The excitation and emission fluorescence spectra of acid extracts of psoriatic scale from five patients were all similar to those of protoporphyrin IX in acid solution. High performance liquid chromatography identified the presence of protoporphyrin IX in the acid extracts from psoriatic scale of the same patients. We conclude that native psoriatic plaques can exhibit red autofluorescence that is due to elevated levels of protoporphyrin IX within scales.
在评估正常皮肤和患病皮肤的自体荧光特性时，我们发现银屑病斑块在用紫外线A（UVA）或蓝光照射时会发出独特的红色荧光。使用配备442nm激发激光的宏观光谱荧光计，在75例银屑病患者中的34例（45%）的斑块内可证实在体内有一个尖锐的荧光发射峰，波长约为635nm。银屑病患者外观正常的皮肤以及66例患有其他皮肤病的患者的皮肤中均未出现此峰。使用与相同激发激光耦合的微观光谱荧光计来获取显示宏观红色自体荧光的斑块中分离的表皮片和真皮的发射光谱。在所研究的所有3例患者中均观察到约635nm处的发射峰，但仅在从表皮获得的光谱上。另外5例患者完整银屑病皮肤垂直显微镜切片的光谱显示该峰起源于角质层。包括银屑病皮肤和正常皮肤的表皮中层和真皮以及正常皮肤角质层在内的其他微区的发射光谱均未显示出635nm的峰。5例患者银屑病鳞屑酸提取物的激发和发射荧光光谱均与酸性溶液中原卟啉IX的光谱相似。高效液相色谱法鉴定出同一患者银屑病鳞屑酸提取物中存在原卟啉IX。我们得出结论，天然银屑病斑块可呈现红色自体荧光，这是由于鳞屑中原卟啉IX水平升高所致。
