10/9/2018 Internal Memorandum - Confidential

10/9/2018 Internal Memorandum - Confidential Information. Do Not Distribute 1 … utilizes low concentration of anionic solution (SDS-0.01%) to remove donor cells and cellular debris … incorporates nuclease treatment resulting in up to 99% DNA removal … uses protease inhibitors to preserve tissue structure & biomechanical properties … is terminally irradiated, neutralizing & eliminating pathogens providing microbial sterility 1 2 3 4 Only DermaPure® with dCELL® Technology delivers on the
four key fundamentals of Tissue Processing Notes:
Hogg P, Rooney P, Ingham E, Kearney JN (2013) Development of a decellularised dermis. Cell Tissue Bank 14:465–474
Hogg P., Rooney P., Leow-Dyke S., Brown C., Ingham E., Kearney J.N. Development of a terminally sterilised decellularised dermis. Cell Tissue Bank. 2015;16:351–359.
Greaves NS, Morris J, Benatar B, Alonso-Rasgado T, Baguneid M, Bayat A (2015) Acute Cutaneous Wounds Treated with Human Decellularised Dermis Show Enhanced Angiogenesis during Healing. PLoS ONE 10(1): e0113209.
Greaves NS, Bayat A (2015). Skin Substitute-Assisted Repair Shows Reduced Dermal Fibrosis in Acute Human Wounds Validated Simultaneously by Histology and Optical Tomography. Wound Rep Reg (2015) 23 483–494
Greaves NS, Benatar B, Baguneid M, Bayat A. Single-stage application of a novel decellularized dermis for treatment-resistant lower limb ulcers: positive outcomes assessed by SIAscopy, laser perfusion, and 3D imaging, with sequential timed histological analysis. Wound Repair Regen. 2013 Nov-Dec;21(6):813-22. doi: 10.1111/wrr.12113. Epub 2013 Oct 17. 1-5<br>

Not all Tissue Processing is the Same… 10/9/2018 Internal Memorandum - Confidential Information. Do Not Distribute 2 DNA Removal
Nuclease Treatment? Remove Donor Cells & Cellular Debris
0.01% Anionic Detergent? 1 2 Tissue integrity can be affected by number of anionic detergents used, concentration, and duration used during processing4

Intact cells still present in donor tissue5,8 Lack of nuclease treatment results in incomplete DNA removal3,4

Residual DNA may trigger immunogenic response that could lead to failure or complications 1,9 99.8% DNA removal 1,2 Low concentration anionic detergent to
remove donor cells & cellular debris 1,2 Alternative Processes Note: See references above on next slide<br>

Not all Tissue Processing is the Same… 10/9/2018 Internal Memorandum - Confidential Information. Do Not Distribute 3 Microbial Sterility & Neutralize Pathogens
Terminally Irradiated? Preserve Tissue Structure
Protease Inhibitors? 3 4 Terminally Irradiated
Sterility Assurance Level (SAL) 10-6 1,2 Protease Inhibitors preserve native tissue structure & biomechanical properties1,2 Alternative Processes Tissue structure and biomechanical properties may be altered when protease inhibitors are not utilized 4

Limits potential to promote regeneration 5,7 Aseptically processed tissue yields an SAL of 10-3

May not eliminate the inherent microbial bioburden in tissue6,8 References:
Hogg P, Rooney P, Ingham E, Kearney JN (2013) Development of a decellularised dermis. Cell Tissue Bank 14:465–474
Hogg P., Rooney P., Leow-Dyke S., Brown C., Ingham E., Kearney J.N. Development of a terminally sterilised decellularised dermis. Cell Tissue Bank. 2015;16:351–359.
Moore MA, Samsell B, Wallis G, Triplett S, Chen S, Jones AL, Qin X. Decellularization of human dermis using non-denaturing anionic detergent and endonuclease: a review. Cell Tissue Bank. 2015;16:249–259.
Carruthers CA, Dearth CL, Reing JE, et al. Histologic characterization of acellular dermal matrices in a porcine model of tissue expander breast reconstruction. Tissue Engineering Part A. 2014;21(1-2):35-44.
Booth, C, et al. Tissue engineering of cardiac valve prostheses I: development and histological characterization of an acellular porcine scaffold. J Heart Valve Dis. 2002;11(4):457-462.
Singh R, Singh D, Singh A. Radiation sterilization of tissue allografts: a review. World J Radiol. 2016;8(4):355-369. doi:10.4329/wjr.v8.i4.355.
Agrawal H, Tholpady SS, Capito AE, Drake DB, Katz AJ (2012) Macrophage phenotypes correspond with remodeling outcomes of various acellular dermal matrices. Open J Regen Med 01:51–59
Hathaway, Jon K. et al. Intact Genetic Material is Present in Commercially Processed Cadaver Allografts Used for Pubovaginal Slings The Journal of Urology , Volume 168 , Issue 3 , 1040 – 1043
Londono, R., Dziki, JL, Haliasmaa, R., Turner, NJ, Leifer, CA, Badylak, SF The effect of cell debris within biologic scaffolds upon the macrophage response. J Biomed Mater Res A 2017 Aug;105(8):2109-2118.<br>