Open AccessRelevance of lymphoproliferative disorders and of anti‐C1 inhibitor autoantibodies in acquired angio‐oedema
Author(s) -
CICARDI M.,
BERETTA A.,
COLOMBO M.,
GIOFFRÉ D.,
CUGNO M.,
AGOSTONI A.
Publication year - 1996
Publication title -
clinical & experimental immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.329
H-Index - 135
eISSN - 1365-2249
pISSN - 0009-9104
DOI - 10.1046/j.1365-2249.1996.d01-866.x
Subject(s) - autoantibody , paraproteins , medicine , lymphoproliferative disorders , antibody , immunology , pathology , lymphoma , monoclonal , monoclonal antibody
We looked for autoantibodies to C1 inhibitor (C1‐INH) and evaluated the relationship of their presence to the associated lymphoproliferative diseases and to the cleaved form of C1‐INH in 13 patients with acquired C1‐INH deficiency (acquired angio‐oedema (AAE)). At the time of manifestation of angio‐oedema symptoms or within a few years the following diseases were diagnosed: liver angioma ( n = 1), M‐components ( n = 7, one of whom also had echinococcal liver cysts), breast cancer ( n = 1), chronic lymphocytic leukaemia (CLL; n = 1); three patients had no associated disease. Anti‐C1‐INH autoantibodies, measured both as immunoglobulin binding to C1‐INH immobilized onto microtitre plates (ELISA) and as plasma inhibitory activity of C1‐INH function, were found in 12 patients. Binding of C1‐INH to paraproteins, transferred to Immobilon after agarose gel electrophoresis, was detectable in five of seven M‐components associated with AAE. Immunoblotting analysis of SDS–PAGE‐separated plasma demonstrated that C1‐INH circulated in the cleaved 96‐kD form in the 12 patients with autoantibodies, but not in the one without. In conclusion, the large majority of our patients have autoantibodies to C1‐INH. Circulating autoantibodies are necessary for the generation of cleaved C1‐INH. The paraproteins associated with AAE are frequently autoantibodies to C1‐INH and thus account for its consumption.