title: Investigation of epidermotropism in canine mycosis fungoides: expression of intercellular adhesion molecule-1 (ICAM-1) and beta-2 integrins.
abstract: In human mycosis fungoides (MF), interactions between LFA-1 (CD11a/CD18) and ICAM-1 (CD54) are involved in lymphocyte adhesion to keratinocytes. The purpose of this study was to evaluate the expression of ICAM-1, beta-2 integrins and class II major histocompatibility complex molecules (MHC II) on keratinocytes and infiltrating lymphocytes in canine MF. Sections of frozen skin biopsy specimens from normal dogs (n = 3) and dogs with MF (n = 17) were evaluated by immunohistochemistry for expression of ICAM-1, beta-2 integrins, and class II MHC molecules. Our results demonstrated that in canine MF, ICAM-1 was expressed variably on epidermal and follicular keratinocytes. The extent of keratinocyte ICAM-1 expression did not correlate with the degree of lymphocyte epithelial infiltration, nor with lymphocyte LFA-1 expression. This was especially evident in cases of Pagetoid reticulosis-like disease in which prominent lymphocyte epidermotropism was not accompanied by keratinocyte ICAM-1 expression. Keratinocyte class II MHC molecule expression did not correlate with keratinocyte ICAM-1 expression. In conclusion, in canine MF, the lack of statistically significant correlations between epithelial lymphocyte infiltration and keratinocyte ICAM-1 expression, and between keratinocyte ICAM-1 and lymphocyte LFA-1 staining, suggests that the LFA-1/ICAM-1 pathway is not the major adhesion mechanism between lymphocytes and keratinocytes. It is suspected that different ligands of the LFA-1 integrin (e.g. ICAM-2) or other adhesion molecules (e.g. CD2/LFA-3, VLA-1) might be involved in the epitheliotropism phenomenon in canine MF. These hypothesis cannot be evaluated in the dog at this time owing to the lack of specific monoclonal antibodies.
authors.affiliation: Department of Pathology, School of Veterinary Medicine, University of California Davis 95616, USA.
authors.forename: T
authors.initials: T
authors.lastname: Olivry
authors.forename: P F
authors.initials: PF
authors.lastname: Moore
authors.forename: D K
authors.initials: DK
authors.lastname: Naydan
authors.forename: D M
authors.initials: DM
authors.lastname: Danilenko
authors.forename: V K
authors.initials: VK
authors.lastname: Affolter
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D001706:Biopsy; D018845:CD11 Antigens / Q000032:analysis; D018821:CD18 Antigens / Q000032:analysis; D004283:Dog Diseases; D004285:Dogs; D000939:Epitopes / Q000032:analysis; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D006801:Humans; D007124:Immunoenzyme Techniques; D016023:Integrins / Q000032:analysis / Q000096:biosynthesis*; D018799:Intercellular Adhesion Molecule-1 / Q000032:analysis / Q000096:biosynthesis*; D016169:Lymphocyte Function-Associated Antigen-1 / Q000032:analysis; D008214:Lymphocytes / Q000276:immunology* / Q000473:pathology; D009182:Mycosis Fungoides / Q000276:immunology / Q000473:pathology / Q000662:veterinary*; D012867:Skin / Q000276:immunology* / Q000473:pathology
chemical_list: D000911:Antibodies, Monoclonal; D018845:CD11 Antigens; D018821:CD18 Antigens; D000939:Epitopes; D000949:Histocompatibility Antigens Class II; D016023:Integrins; D016169:Lymphocyte Function-Associated Antigen-1; D018799:Intercellular Adhesion Molecule-1