Protocol B was an adaptation of protocol A and involved the same steps however specimens were submersed in 0.25% trypsin(Sigma-Aldrich, USA) for three hours after being subject to treatment with 2% DNAse (Sigma-Aldrich, USA). This was followed by an overnight wash in deionized water as before. Trypsin was used only for 7 cycles so as to avoid damaging the ECM.