Detection of anti-cytokeratin 8 antibody in the serum of patients with cryptogenic fibrosing alveolitis and pulmonary fibrosis associated with collagen vascular disorders
- Naomi Dobashia,
- Jiro Fujitaa,
- Yuji Ohtsukie,
- Ichiro Yamadorid,
- Takeo Yoshinouchib,
- Tadashi Kameic,
- Michiaki Tokudaa,
- Satoko Hojoa,
- Hiroki Okadaa,
- Jiro Takaharaa
- aFirst Department of Internal Medicine, Kagawa Medical University, 1750–1 Miki-cho, Kita-gun, Kagawa 761–0793, Japan, bDepartment of Respiratory Medicine, Gamagohri City Hospital, Aichi, Japan, cDepartment of Internal Medicine, Kagawa Prefectural Central Hospital, Kagawa, Japan, dDepartment of Pathology, Okayama University Medical School, Okayama, Japan, eDepartment of Pathology, Kochi Medical School, Kochi, Japan
- Dr J Fujita.
- Received 27 February 1998
- Revision requested 27 April 1998
- Revised 26 May 1998
- Accepted 15 June 1998
Abstract
BACKGROUND It has been suggested that the humoral immune system plays a role in the pathogenesis of cryptogenic fibrosing alveolitis (CFA). Although circulating autoantibodies to lung protein(s) have been suggested, none of the lung proteins have been characterised. The purpose of this study was to determine the antigen to which the serum from patients with pulmonary fibrosis reacted.
METHODS The anti-A549 cell antibody was characterised in a patient with CFA using Western immunoblotting and immunohistochemical staining of A549 cells. As we identified that one of the antibodies against A549 cells was anti-cytokeratin 8, the expression of mRNA of cytokeratin 8 in A549 cells was evaluated. In addition, we attempted to establish an enzyme linked immunosorbent assay to measure the levels of anti-cytokeratin 8 antibody in the serum of patients with CFA and pulmonary fibrosis associated with collagen vascular disorders (PF-CVD).
RESULTS Initially two anti-A549 cell antibodies were detected in the serum of patients with pulmonary fibrosis, one of which was characterised as anti-cytokeratin 8 antibody by Western immunoblotting. We were able to establish an ELISA to measure anti-cytokeratin 8 antibody and found significantly higher levels in patients with CFA and PF-CVD than in normal volunteers, patients with sarcoidosis, pneumonia, and pulmonary emphysema.
CONCLUSIONS One of the anti-A549 cell antibodies in the serum of patients with CFA was against cytokeratin 8. The serum levels of anti-cytokeratin 8 antibody were increased in patients with CFA and PF-CVD. These results suggest that anti-cytokeratin 8 antibody may be involved in the process of lung injury in pulmonary fibrosis.
