The chick chorioallantoic membrane as test system for biocompatible materials

Area of Science:

• Biomaterials Science
• Histology
• Developmental Biology

Background:

• Biologic and non-biologic materials are used clinically as hemostyptica, vascular prostheses, and temporary skin substitutes.
• Evaluating the biocompatibility and tissue reaction of these materials is crucial for clinical application.

Purpose of the Study:

• To assess the biocompatibility and connective tissue reaction of various hemostatic, vascular, and skin substitute materials using the chick chorioallantoic membrane (CAM) model.
• To correlate in vivo CAM findings with clinical observations.

Main Methods:

• Biologic (cellulose gauze, fibrin adhesive, collagen sponge, gelatin sponge) and non-biologic (expanded polytetrafluoroethylene, Dacron, polyurethane foam) materials were implanted onto the CAM of chick embryos.
• Histological examination was performed to evaluate tissue response, including inflammation, cell infiltration, and tissue ingrowth.

Main Results:

• Cellulose gauze (Tabotamp) showed an intact CAM.
• Fibrin adhesive (Tissucol), collagen sponge (Tachotop), and gelatin sponge (Gelfoam) induced varying degrees of connective tissue ingrowth and cellular response (fibroblasts, neutrophils, giant cells).
• Non-biologic materials caused diverse reactions: polytetrafluoroethylene induced squamous metaplasia, Dacron caused ulceration and giant cell reaction, and polyurethane foam led to bleeding.

Conclusions:

• The chick chorioallantoic membrane (CAM) serves as a viable in vivo model for screening the biocompatibility and connective tissue response of clinical biomaterials.
• Observed histological reactions correlate with known clinical performance, supporting the CAM model's utility.