I have successfully cultured nasal polyps epithelial culture cells using BEGM medium with streptomycin and fungizone, in T25 flasks but i have problems while growing from brushes and i also have some contamination problems.
Is your contamination bacterial? It may be worth trying to use antibiotics from a few different classes. More frequent media changes once cells have adhered will also help curb existing bacterial contamination.
Thank you for your suggestion. They are fungal contamination, white colour grainy mold. I have tried to use cell culture inserts for brushes and the success rate is higher.