Abstract: YANG Sheng-ju*, MENG Guo-liang, CHEN Xiao-dong. *Department of Dermatology and Venereology, Affiliated Hospital of Nantong University, Nantong 226001, Jiangsu, China Corresponding author: CHEN Xiao-dong, Email: dermatochen@163.com 【Abstract】 Objective To observe the expression and location of galactose β-1,4-glycosidic bonds （Gal β-1,4-GlcNAc） in keloid tissue, and to investigate the role of glycoprotein galactosylation in the formation of keloid. Methods This study included 10 keloid tissue specimens, 7 hyperplastic scar tissue specimens, and 6 normal skin specimens. Lectin blot analysis was performed to measure the glycosylation level of glycoproteins, saturated picric acid - Sirius red staining followed by polarization microscopy to observe the type, expression and distribution of collagens in these specimens. The type I/type III collagen ratio was calculated. Immunofluorescence-based histochemistry was carried out by using Ricinus communis agglutinin I to analyze the expression and location of Gal β-1,4-GlcNAc in these skin samples, and double immunofluorescent staining to observe the colocalization of Gal β-1,4-GlcNAc and type Ⅰprocollagen α1. Results Compared with the normal skin tissue, the keloid tissue showed a significant increase in the expression of Gal β-1,4-GlcNAc in glycoproteins with a relative molecular mass of 30 000 to 40 000. Polarization microscopy revealed that there was a considerable expression of typeⅠcollagen fibers, which amounted to （71.53 ± 4.03）% in all the collagen fibers. The type I/type III collagen ratio was significantly higher in keloid tissue specimens than in normal tissue specimens （2.56 ± 0.53 vs. 0.91 ± 0.11, P < 0.05）. Fluorescence microscopy showed that Gal β-1,4-GlcNAc was uniformly distributed in the membrane and cytoplasm of fibroblasts in keloid tissue, and the expression intensity of Gal β-1,4-GlcNAc in keloid tissue was notably stronger than that in normal skin tissue. There was a colocalization between Gal β-1,4-GlcNAc and typeⅠprocollagen α1 in keloid tissue. Conclusions The expression of Gal β-1,4-GlcNAc, which is mainly observed in fibroblasts, is upregulated in keloid tissue, suggesting that Gal β-1,4-GlcNAc may be involved in the modulation of factors responsible for excessive fibre formation during the repair process of keloid. 【Key words】 Keloid; Galβ-1,4GlcNAc; Collagen type Ⅰ; Ricin

Key words: Galβ-1,4GlcNAc