The PathClear designation in HC20+ basement membrane extract indicates that in addition to standard sterility, endotoxin and MAP testing, the BME is tested by PCR and is clear of a battery of 31 pathogens and viruses, including LDEV, which makes it useful for in vivo applications. Each lot is qualified in biological performance assays. PathClear HC20+ was developed for use in in vivo applications where higher protein concentrations facilitate faster gelling times, increased gel strength, and successful establishment and growth of tumor cells in nude mice. It offers lot-to-lot consistency and controlled protein concentrations to support in vivo angiogenesis assays and tumorigenicity assays.