Abstract
It has been confirmed that neuroendocrine regulation involves in the pathogenesis of psoriasis, but the association between neuroendocrine and skin immune is still unknown. The present study aimed to explore the relationship of Merkel cells in the skin lesions and the pathogenesis of psoriasis. The ultrastructure of Merkel cells was observed under an electron microscope and immunohistochemistry was performed to detect the expressions of CK20, CK19, CK18, S100A7, SP and CD13 in the skin lesions of psoriasis patients and normal controls. Our results showed the neuroendocrine granules in the Merkel cells increased significantly at the progressive stage of psoriasis; the expressions of CK20, CK19 and CK18 in the skin lesions were markedly higher than those in normal controls, the CK20 expression at the progressive stage was significantly higher than that at the initial stage and recovery stage; the expressions of S100A7, SP and CD13 in the skin lesions at the progressive stage were higher than those in the initial stage and recovery stage and positively related to the CK20 expression. Merkel cells may play an important neuroendocrine regulatory role in the pathogenesis of psoriasis. Key words: Merkel cell, psoriasis neuroendocrine, pathogenesis.
Highlights
Shepherd proposed that immune function without nervous regulation may be sufficient for local responsiveness to subsequent challenge (Shepherd et al, 2005) and the nervous regulation played an important role in the homeostasis of immune function including skin immune
Merkel cells localized in the basal layer of the epidermis were closely connected to the nerve endings with clear cytoplasm and irregular nucleus and were distributed between epidermal cells with digitations
Merkel cells had the features of epidermal cells while, under an electron microscope, neuroendocrine granules of 50 ~ 100 nm were seen
Summary
Shepherd proposed that immune function without nervous regulation may be sufficient for local responsiveness to subsequent challenge (Shepherd et al, 2005) and the nervous regulation played an important role in the homeostasis of immune function including skin immune. Since Misery put forward the concept of neuroimmuno-cutaneous system (NICS) in 1996 (Misery, 1996) and O’Sullivan (1998) concept of neruo-immunocutaneous-endocrine network (NICE) in 1998, increasing attention has been paid to the nervous regulation of skin immune which is a focus in the studies of skin immune. Research has demonstrated that the serum levels of neuropeptides in the psoriasis patients including substances P (SP), vasoactive intestinal peptide (VIP) and calcitonin gene-related peptide (CGRP) are markedly higher than those in healthy controls (Reich et al, 2007), the nerve fibers in the skin lesions of patients with psoriasis vulgaris are dramatically longer than those in healthy subjects (Wang et al, 2004) and the nerve growth factor (NGF) expression in the skin lesions is significantly increased when compared with that in controls (Ye et al, 2005). It was believed that Merkel cells were the skin receptive cells of mechanical stimulation signal
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have