Chick embryo chorioallantoic membrane model to study human recurrent respiratory papilloma growth and vascularity

Abstract

Introduction. The aim of this study was to develop chick embryo chorioallantoic membrane (CAM) model of recurrent respiratory papilloma (RPP). Material and methods. Fresh RRP tissue samples obtained from 13 patients were implanted in 174 chick embryo CAMs. Morphological, morphometric, and angiogenic changes in the CAM and chorionic epithelium were evaluated up until 7 days after the implantation. Immunohistochemical analysis was performed to detect cytokeratins and tumor endothelial cells and to evaluate proliferative capacity of the RRP before and after implantation on the CAM. Results. The implanted RRP tissue samples survived on CAM in 73% of cases retaining their essential morphologic characteristics and proliferative capacity of the original tumor. Implants induced thickening of both, the CAM (241-560%, p = 0.001) and the chorionic epithelium (107-151%, p = 0.001), and increasing of number of blood vessels (37-85%, p = 0.001). Conclusions. Results of the present study confirmed that chick embryo CAM is a relevant host medium for RRP fresh tissue implantation. This CAM assay demonstrated the specific RRP tumor growth pattern after implantation on the CAM and provided the first morphological and morphometric characterization of the RRP CAM model that opens new perspectives to study this disease.