Related Experiment Videos
Cyclooxygenase-2 expression in experimental post-transplant obliterative bronchiolitis
Outi E Päiväniemi1, Paula K Maasilta, Hanni S Alho
1Department of Surgery, Helsinki University Hospital, Finland.
The Journal of Pathology
|October 12, 2004
Summary
Cyclooxygenase (COX)-2 is involved in early post-transplant obliterative bronchiolitis (OB) development, appearing in airway epithelial cells before injury. Its expression in macrophages and fibroblasts also correlates with inflammation and fibrosis in OB.
Area of Science:
- Transplantation immunology
- Inflammatory pathways
- Graft rejection mechanisms
Background:
- Post-transplant obliterative bronchiolitis (OB) is a major cause of graft failure.
- Cyclooxygenase (COX)-2 is implicated in inflammatory processes.
- The specific role of COX-2 in OB pathogenesis remains unclear.
Purpose of the Study:
- To investigate the role of COX-2 in the development of post-transplant OB.
- To analyze COX-2 expression in a heterotopic bronchial allograft model in pigs.
Main Methods:
- A heterotopic bronchial porcine model was used, with allografts transplanted subcutaneously.
- Groups received no treatment, or immunosuppressants (cyclosporine A, methylprednisolone, azathioprine, everolimus).
- Histology and immunohistochemistry for COX-2 were performed on harvested grafts.
Main Results:
- COX-2 expression was observed in epithelial cells early after transplantation, preceding injury and obliteration.
- In non-treated allografts, epithelial loss led to obliteration.
- Immunosuppressive treatment, especially with everolimus, delayed or prevented OB.
- COX-2 was also expressed in macrophages and fibroblasts during inflammation and fibrosis.
Conclusions:
- COX-2 is induced in airway epithelial cells in the early stages of OB development.
- COX-2 expression in inflammatory cells suggests a role in OB pathogenesis.
- Further studies are needed to confirm the causal relationship between COX-2 and OB development.