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Pig Islets (PI) are clearly the xenogeneic donor islet of choice for human islet transplant. Pig insulin is known to work well in the human without antibody problems. Furthermore, newer short-term immunosuppression can markedly reduce early graft loss with PI and tolerance induction can even be demonstrated in some discordant xenografts. Isolation of PI remains a major problem with islet fragmentation and islet loss during digestion. In addition, PI undergo a high rate of apoptosis following Isolation in culture which can result in 50.95% loss of PI in 24-48 hours. We initially observed that PI embedded in extracellular adherent matrix exhibited an Anchorage- Dependent cell growth and survival with viability of >80% (Ethidium Bromide/ Acridine Orange Assay - EB/AO) at 20 days (p<0.01 with controls). We tested the so-called "Tensegrity concept" that cell viability and growth in culture depends on adhesion and extracellular integrin structuring and "scaffolding". Tensegrity is optimal when the cell cytoskeleton and the extracellular matrix integrate to achieve a physiological balance of intra and extracellular mechanical tension. By shortening collagenase digestion to yield PI attached to acinar matrix cell remnants, we sought to provide a potential extracellular structure to develop tensegrity Control PI digestions showed 95% purity with pure islets tree of attached acinar and extracellular matrix elements, but a loss of EB/AO viability to 40% and 10% in 24 and 48 hours. In contrast. the matrix-embedded PI had a purity of only 52% but an EB/AO viability of 93% and 86% at 24 and 48 hours and 65% at 30.35 days(p<0.05) At 1 month, the acinar tissue had largely died but fibrous stands remained attached to the cells. Islet function in static incubation was excellent with a insulin rise of 420% in response to a increased glucose incubation solution (normal for fresh islets=320%, p=>0.10) Thus, incomplete digestion of PI with retention of attached elements of the acinar and extracellular matrices apparently supplies a tensegrity (extracellular matrix scaffolding) which promotes long term growth and viability of PI in culture. We conclude that incomplete digestion of islets and/or imbedding islets in extracellular maw, markedly enhances the viability and long term yield of PI and maybe the technique of choice for PI digestion and preparation of PI for culture and/or transplantation.