Autofluorescence of eccrine sweat glands

Background/Purpose The monitoring of autofluorescence in skin tissue samples can have diagnostic and therapy significance. In this study, we are the first to describe autofluorescence of eccrine sweat glands, which is important and helpful for the diagnosis and therapy of diseases that involve the eccrine sweat glands. Methods Eccrine sweat gland autofluorescence in haematoxylin‐eosin ( HE ) stained skin tissue sections was observed under a fluorescence microscope, which was compared to the immunofluorescence of keratin 19 and 15 in the skin tissue sections. The single eccrine sweat glands from five volunteers including three males and two females were isolated and also observed under a fluorescence microscope. The autofluorescence intensity of the single eccrine sweat gland was measured using a laser confocal scanning microscope system. Results Eccrine sweat gland autofluorescence in HE stained skin tissue sections appears green under GFP fliter system (470/40 nm) and red under N2.1 fliter system (515–560 nm). Furthermore, the single eccrine sweat gland showed various autofluorescence colours, including green under wide blue and red under wide green. The autofluorescence intensity of the single eccrine sweat gland was measured. The spectrum excited at 488 nm exhibited two peaks located at approximately 530 nm (11.54 ± 4.66) and 590 nm (10.38 ± 4.33). The results suggest flavin and lipopigment as the endogenous fluorophores. Conclusion The autofluorescence of the HE stained eccrine sweat gland sections is simple and helpful for easily determining the structure of eccrine sweat glands. The autofluorescence of the single eccrine sweat gland may be due to the existence of flavin and lipopigment.