A Comparative Immunohistochemical Analysis of Langerhans Cells in Oral Mucosa, Oral Lichen Planus and Oral Squamous Cell Carcinoma

Oral lichen planus - case report

This paper presents the case of a 58-year-old heavy smoker female who came to our clinic with acute pain, as well as mastication and feeding difficulties. The macroscopic examination revealed oral erosive lesions and ulcerations. The polymorphic aspect of the lesions required the differential diagnosis of oral erythroplakia or carcinoma, which were excluded by biopsy. At the same time, we assessed the expression of S100 protein, Ki67 and the cluster of differentiation (CD) 4, CD8 (T-cell) and CD20 (B-cell) immune cell markers by immunohistochemical analysis. As a result, after the clinical and pathological assessment, the diagnosis of oral lichen planus was established, and a therapy plan was conducted. We observed a favorable clinical evolution after the administration of corticosteroids and immunomodulatory agents.

Marking vertebrates langerhans cells, from fish to mammals

Langerhans cells (LCs) are specialized dendritic cells (DCs) that play a defense role in recognizing foreign antigens, in tissue where antigenic exposures occur, as in the skin and mucous membranes. LCs are able to continuously move within the tissues thanks to dendritic contraction and distension performing their surveillance and/or phagocytosis role. These cells are characterized by the presence of Birbeck granules in their cytoplasm, involved in endocytosis. LCs have been characterized in several classes of vertebrates, from fish to mammals using different histological and molecular techniques. The aim of the present review is to define the state of art and the need of information about immunohistochemical markers of LCs in different classes of vertebrates. The most used immunohistochemical (IHC) markers are Langerin/CD207, CD1a, S-100 and TLR. These IHC markers are described in relation to their finding in different vertebrate classes with phylogenetical considerations. Among the four markers, Langerin/CD207 and TLR have the widest spectrum of cross reactivity in LCs.