Epidermal nuclear IgG deposition in normal skin: characterization by anti-ribonucleoprotein IgG-Fab fragments.
Epidermal nuclear IgG deposition in clinically normal skin may occur in patients with scleroderma or scleroderma-like features. In order to evaluate the mechanisms of the fixation, Fab fragments of anti-RNP IgG antibodies, obtained after papain digestion, were incubated for increasing times with various substrates: human skin, human mononuclear cells, cultured human fibroblasts and rabbit lip. Our results showed that anit-RNP IgG-Fab fragments could penetrate most of the living cells of human skin and rabbit lip and, to a lesser degree, mononuclear cells and poorly cultured fibroblasts. No ability to fix was found either with anti-RNP IgG-Fe fragments or with anti-nDNA/DNP IgG-Fab. It was concluded that anti-RNP IgG could penetrate viable epidermal and non-epidermal cells and that surface Fe receptors must play a minor role in the cellular penetration of antibodies.
D000818:Animals; D002467:Cell Nucleus / Q000276:immunology; D000078404:Epidermal Cells; D004817:Epidermis / Q000276:immunology*; D005455:Fluorescent Antibody Technique; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000032:analysis*; D007141:Immunoglobulin Fc Fragments / Q000032:analysis; D007074:Immunoglobulin G / Q000302:isolation & purification*; D009698:Nucleoproteins / Q000276:immunology*; D011817:Rabbits; D012261:Ribonucleoproteins / Q000276:immunology*
D007140:Immunoglobulin Fab Fragments; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D009698:Nucleoproteins; D012261:Ribonucleoproteins