Multiple-layer, formed-in-place immunoisolation membrane structures for implantation of cells in host tissue

A permeable structure forming a chamber to hold living cells, the permeable structure comprising a first permeable region surrounding at least a portion of the chamber having a conformation that, when implanted in host tissue, substantially blocks penetration of host cells into the chamber while permitting solute transport between the host and cells, a second permeable region overlying the first permeable region having a conformation that, when implanted in host tissue, forms a permeable interface with host tissue that promotes the growth of vascular structures near the permeable interface while permitting solute transport between the host and cells, and a third permeable region between the first and second permeable regions comprising a polymer material layer formed in place between the first and second permeable regions, the third permeable region bonding the first and second permeable regions together and having a conformation that, when implanted in host tissue permits solute transport between the first and second permeable regions.

A permeable structure forming a chamber to hold living cells, the permeable structure comprising a first permeable region surrounding at least a portion of the chamber having a conformation that, when implanted in host tissue, substantially blocks penetration of host cells into the chamber while permitting solute transport between the host and cells, a second permeable region overlying the first permeable region having a conformation that, when implanted in host tissue, forms a permeable interface with host tissue that permits solute transport between the host and cells, the first permeable region comprising an array of three dimensional strands having a first dimension larger than a second and third dimensions and, for the majority of strands, neither of the second and third dimensions exceeds about 5 .mu.m, and a third permeable region between the first and second permeable regions comprising a polymer material layer formed in place between the first and second permeable regions, the third permeable region bonding the first and second permeable regions together and having a conformation that, when implanted in host tissue, permits solute transport between the first and second permeable regions.

A permeable structure forming a chamber to hold living cells, the structure comprising a permeable layer surrounding the chamber that, when implanted in host tissue, blocks contact between cells in the chamber and host cells while permitting transport of solutes between the host and cells, the permeable layer comprising a first immunoisolation region having a conformation that, when implanted in host tissue, substantially blocks penetration of host inflammatory cells, and a second immunoisolation region distinct from the first region, the second region having a conformation that, when implanted in host tissue, also substantially blocks penetration of host inflammatory cells, the first and second regions being mutually arranged in the permeable layer to together provide a redundant immunoisolation barrier.

A permeable structure forming a chamber to hold living cells, the structure comprising a permeable membrane surrounding the chamber having a conformation that, when implanted in host tissue, substantially blocks penetration of at least host inflammatory cells into the chamber while permitting solute transport between the host and cells, the permeable membrane having a surface, and an auxiliary permeable layer bonded in substantially continuous contact with the permeable membrane surface to substantially block infiltration of host cells between the auxiliary permeable layer and the permeable surface, the auxiliary permeable layer having a conformation that, when implanted in host tissue, substantially blocks penetration of at least host inflammatory cells while permitting solute transport through the permeable membrane.

A permeable structure forming a chamber to hold living cells, the structure comprising a permeable membrane surrounding the chamber having a conformation that, when implanted in host tissue, substantially blocks penetration of at least host inflammatory cells into the chamber while permitting solute transport between the host and cells, the permeable membrane having a surface, and an auxiliary permeable layer comprising a solution of polymer material brought into contact with the permeable membrane surface and formed in place on the permeable membrane surface, the auxiliary permeable layer having a conformation that, when implanted in host tissue, substantially blocks penetration of at least host inflammatory cells while permitting solute transport through the permeable membrane.