83 - Antibodies to laminin

Abstract

Laminins are major components of the basement membrane, forming essential contacts with cells and other components of the basal lamina, thereby inducing dynamic interactions in the tissue through intracellular signaling promoting and regulating cell adhesion, spreading, and differentiation. Autoantibodies to laminin have been found in autoimmune disorders such as anti-epiligrin cicatritial pemphigoid (AECP), rheumatic fever, and systemic lupus erythematosus (SLE) as well as in Chagas disease, and in women with recurrent miscarriages and infertility. The antibodies bind mainly the G domain of the αchain of laminin, and in some cases they seem to appear as a consequence of antigenic mimicry. Their pathogenic role and diagnostic value in most of these clinical conditions have not yet been clarified. In AECP, patients with circulating IgG antibodies to laminin show binding to the dermal side of salt split skin by Enzyme-linked immunosorbent assay (IIF). An anti-laminin 5 assay is performed only by specialized laboratories utilizing either the sensitive method of immunoprecipitation on biosynthetically radiolabled human keratinocyte extracts or culture media, or by the more practical method of immunoblotting on extracts of human keratinocytes or their ECM, or on purified laminin 5.