Walter L. Binder

Immunopathology of psoriasis.

SummaryImmunofluorescence (IF) studies by the direct and indirect methods demonstrate immunoglobulins and complement bound in vivo in psoriatic scales. The IF pattern is comparable to that of stratum corneum antibodies (SCAb) bound in vitro on specific substrate, as visualized by the indirect IF method. Formation of immune complexes can be responsible for the “squirting papilla” phenomenon, and conversion of the stratum corneum — which is normally an inaccessible antigen — into its reactive form seems to be brought about by proteases of polymorphonuclear leukocytes. Stimulation of protease production by polymorphonuclears appears to be an important factor in the pathogenesis of psoriasis. The stratum corneum of the epidermis is probably the target, and becomes an antigen for SCAb present in the circulation.ZusammenfassungUntersuchungen der psoriatischen Hautveränderungen mittels der direkten und indirekten Immunofluorescenzmethode zeigen in der Hornschicht Immunoglobulin- und Komplementablagerungen auf. Das IF-Muster ist dasselbe wie bei der Bindung der im normalen Serum auftretenden anti-Stratum corneum-Antikörper an dem spezifischen Substrat, d.h. normaler Hornschicht. Die Bildung von Immunkomplexen zusammengesetzt von anti-Stratum corneum-Antikörpern scheint das Phänomen der «Squirting papilla» zu verursachen, wobei das normalerweise nicht zugängliche Stratum corneum unter der Einwirkung von Traumen oder Leukocyten-Proteinasen antigenisch wird. Die Proteinase-Produktion durch angeregte polymorphonukleare Leukocyten ist vermutlich ein wichtiger pathogenetischer Faktor in Psoriasis, wobei das Stratum corneum das Target ihrer Einwirkung ist und reaktiv (antigenisch) wird, was die in vivo-Fixation der Stratum corneum-Antikörper ermöglicht.

In vitro effects of pemphigus antibodies on skin

Acantholysis occurring in rhesus monkey skin explants cultured on sera of 9 pemphigus patients was found to be largely dependent on the titre of intercellular antibody, and not on the participation of complement. Skin explants cultured on normal human sera and pemphigoid sera failed to give rise to intercellular staining or to develop lesions.

Antinuclear Antibodies (ANA) and Complement Fixing ANA in Systemic Connective Tissue Diseases

Screening for antinuclear antibodies (ANA) with parallel tests for complement fixing ANA (C-ANA) reveal that C-ANA react either as strongly as or more strongly than ANA in most cases of systemic lupus erythematosus (SLE) and related disorders including CREST syndrome. But sera of drug induced LE and other ANA positive subjects have weak or no C-ANA. (P < 0.0005). Titrations with parallel C-ANA/ANA tests of two cases reveal primarily ANA and less C-ANA reactions in a case of drug induced LE but in CREST syndrome both ANA and C-ANA tests yield elevated titers with stronger C-ANA reactions. These findings point to distinct immunochemical mechanisms in C-ANA and ANA reactions.