Model and Tissue Design
SynDaver™ and SynTissue™ brand products are designed to mimic specific human tissues or organs. The chemical, physical, and mechanical properties these tissues mimic are based on data derived from testing LIVING animal tissues. We do limited testing on live human tissues, but for the most part we employ a porcine model as the primary animal subject in our live tissue tests. This is justified by the similarity between human and porcine tissues on the most basic level. For example, heart valves, arteries, fascia, and brain matter are similar in structure and function whether they are sourced from a human or porcine model, and this similarity is underscored by the established practice of porcine tissue transplantation into humans.

The drawbacks to using live animal data in this application are limited. The alternative (using live human tissue on a large scale) is not feasible for a number of reasons. First of all, the logistical and regulatory issues associated with testing live human tissues make collecting that type of data extremely difficult. While living human tissues are difficult to obtain in small quantities, they are impossible to obtain in statistically useful quantities, and there are very high regulatory hurdles that must be overcome in order to gain access to even a single live human subject. In addition, since the properties of any living tissue generally begin to change immediately after death, any samples harvested would need to be tested at the sampling location to minimize the lapse between harvest and data collection. This would require tissue analogs to be tested at a hospital, which would be impractical and prohibitively expensive given the high volume of testing required.

Of course, a great deal of information on the physical properties of human cadaveric tissue is available in the literature, and this data is one potential source for the design of tissue analogs. However, we do not use this type of data as design criteria. First of all, the properties of living and dead tissues are different, with the discrepancy increasing with time elapsed after death and even more so after freezing or chemical preservation. In addition, employing data from literature would preclude control of tissue harvest, sample preparation, test design, and test method. This in turn would prevent validation of the resulting tissue analogs since this process involves be testing target tissues and tissue analogs under the same conditions. For this reason we do not consider synthetic tissue analogs based on cadaver data to be effective replacements for live tissue.