Significance of DC-LAMP and DC-SIGN expression in psoriasis vulgaris lesions

To detect and compare the expression levels of two dendritic cell proteins, namely Dendritic Cell Lysosome-Associated Membrane Protein (DC-LAMP) and Dendritic Cell-Specific ICAM-3 Grabbing Non-integrin (DC-SIGN) in psoriasis vulgaris lesions and normal skin tissues.We used Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and immunohistochemical analysis to detect the expression of DC-LAMP and DC-SIGN in 33 samples representing plaque lesions of psoriasis vulgaris and 11 normal skin samples from healthy volunteers.RT-PCR The expression levels of DC-LAMP and DC-SIGN were higher in samples of psoriasis vulgaris lesions than in that of normal skin, based on RT-PCR results.Whereas DC-LAMP staining was mostly cytoplasmic in keratinocytes of basal and spinous epidermis and dermal dendritic cells, DC-SIGN staining was both cytoplasmic and nuclear in keratinocytes of spinous epidermis and dermal dendritic cells. The expression levels of DC-LAMP and DC-SIGN proteins were significantly higher in psoriasis vulgaris lesions when compared with normal skin tissues (P0.01). Furthermore, we found a positive correlation between high DC-LAMP and high DC-SIGN expression levels in psoriasis vulgaris lesions (P0.05, r=0.368).Compared with normal tissues, the levels of DC-LAMP and DC-SIGN were higher in psoriasis vulgaris lesions. Both DC-LAMP and DC-SIGN proteins may be involved in the pathogenesis of psoriasis vulgaris. The high expression of DC-LAMP may be associated with the altered differentiation of keratynocytes in psoriasis.