Staining of nasal mucosa to examine remodelling.

BACKGROUND AND OBJECTIVE: The process of embedding tissue in paraffin degrades many important molecules involved in respiratory epithelial remodelling. We therefore examined alternative methods. METHODS: Inferior turbinate and nasal polyp biopsies were either placed in formalin or immediately snap-frozen in the operating theatre. Novel protocols for staining remodelling markers were compared with current methods. RESULTS: Our method, using a mixture of three lectins, stained a significantly greater proportion of samples, compared with using Ulex europeaus lectin alone (84 vs 62 per cent; p <0.005). Comparison of different proliferation markers showed that Ki67 was more suitable than proliferating cell nuclear antigen for frozen sections. CONCLUSIONS: This study indicates that our robust, repeatable methods for examining whole mounts and for staining capillaries, cell proliferation and nuclei on the same section of nasal mucosa are superior to current methods. The use of fresh tissue that has not been paraffin-embedded would allow a greater suite of epitopes to be examined in the future.