Antibodies against microfibrils of developing connective tissue in patients with inflammatory conditions.

Sera from patients with chronic inflammatory disease were tested for the presence of connective tissue antibodies. Fetal human skin was used as a substrate in an indirect immunofluorescence assay. Histological staining for connective tissue fibres, antibodies to connective tissue components and immunoelectron microscopy were used to identify the antigenic structures. Some antigenic fibrils were associated with elastin. By immunoelectron microscopy antigenic extracellular microfibrillar structures were identified. Antibodies against these microfibrils were detected in higher titres only in chronic inflammation (14%). Our results suggest that antibodies against connective tissues microfibrils may occur in human sera.