Method and composition for hypothermic storage of placental tissue

Abstract

A tissue storage solution includes hypothermic storage compositions and methods. The hypothermic storage composition includes media containing Dulbecco's modified Eagle's medium (DMEM) and albumin. A method of hypothermically storing tissue includes storing such tissue in a storage medium including DMEM and albumin. A method for wound or defect treatment includes applying tissue, stored in a hypothermic storage medium containing DMEM and albumin, to the site of such wound or defect.

What is claimed is: 
     
         1 . A tissue storage method comprising hypothermically storing a placental membrane in a solution including Dulbecco's modified Eagle's medium (DMEM) and human plasma albumin. 
     
     
         2 . The method according to  claim 1 , wherein the human plasma albumin is recombinant human albumin (rhA). 
     
     
         3 . The method according to  claim 1 , wherein the placental membrane is hypothermically stored in the solution at a temperate ranging between more than 0° C. and less than about 10° C. 
     
     
         4 . The method according to  claim 1 , wherein the placental membrane and the solution are hypothermically stored in a sealed container. 
     
     
         5 . The method according to  claim 1 , comprising storing a placental membrane in a solution including DMEM and human plasma albumin for at least 14 days. 
     
     
         6 . The method according to  claim 1 , wherein the placental membrane exhibits a ratio of live cells to dead cells of greater than 1.5 following thirty-six hours of being hypothermically stored in the solution. 
     
     
         7 . The method according to  claim 1 , wherein the placental membrane exhibits a ratio of live cells to dead cells greater than 1.0 following one hundred twenty hours of being hypothermically stored in the solution. 
     
     
         8 . The method according to  claim 1 , wherein the placental membrane exhibits a ratio of live cells to dead cells greater than 2.0 following three hundred sixty hours of being hypothermically stored in the solution. 
     
     
         9 . The method according to  claim 1 , wherein the placental membrane exhibits a ratio of live cells to dead cells of greater than about 1.5 following seven hundred twenty hours of being hypothermically stored in the solution. 
     
     
         10 . The method according to  claim 1 , wherein the placental membrane exhibits a ratio of live cells to dead cells of about 1.0 or more following one thousand hours of being hypothermically stored in the solution. 
     
     
         11 . The method according to  1 , claim wherein the placental membrane exhibits a cell viability in a range between about 45% and 85% following one thousand hours of being hypothermically stored in the solution. 
     
     
         12 . The method according  claim 1 , further comprising promoting preservation of membrane integrity of the placental membrane by including an effective amount of the human plasma albumin in the solution. 
     
     
         13 . The method according to  claim 12 , wherein promoting preservation of membrane integrity of the placental membrane includes promoting preservation of a thickness of the placental membrane, reducing damage to an epithelial cell layer of the placental membrane and promoting cell retention within an extracellular matrix of the placental membrane. 
     
     
         14 . The method according to  claim 1 , further comprising promoting cell viability of the placental membrane by including an effective amount of the human plasma albumin in the solution. 
     
     
         15 . The method according to  claim 1 , further comprising promoting preservation of total protein content of the placental membrane by including an effective amount of the human plasma albumin in the solution. 
     
     
         16 . The method according to  claim 1 , wherein the placental membrane has a total protein content of more than about 450 ng of protein per mg of the placental membrane following twenty-four hours of being hypothermically stored in the solution. 
     
     
         17 . The method according to  claim 16 , wherein the placental membrane has a total protein content of more than about 300 ng of protein per mg of the placental membrane following one thousand hours of being hypothermically stored in the solution. 
     
     
         18 . The method according to  claim 1 , further comprising promoting preservation of extracellular matrix proteins of the placental membrane by including an effective amount of the human plasma albumin in the solution. 
     
     
         19 . The method according to  claim 1 , further comprising promoting a reduction of extracellular matrix metalloproteinases within the placental membrane by including an effective amount of the human plasma albumin in the solution. 
     
     
         20 . The method according to  claim 1 , further comprising promoting preservation of tissue inhibitor of matrix metalloproteinases 1, 2 and 4 within the placental membrane by including an effective amount of the human plasma albumin in the solution. 
     
     
         21 . The method according to  claim 1 , wherein the placental membrane has a tissue inhibitor of matrix metalloproteinases 1, 2 and 4 protein content of more than 400 ng of protein per mg of the placental membrane following twenty-four hours of being hypothermically stored in the solution. 
     
     
         22 . The method according to  claim 1 , wherein the placental membrane has a tissue inhibitor of matrix metalloproteinases 1, 2 and 4 protein content of more than 250 ng of protein per mg of the placental membrane following one-thousand hours of being hypothermically stored in the solution. 
     
     
         23 . The method according to  claim 1 , wherein the placental membrane is hypothermically stored between nested trays. 
     
     
         24 . The method according to  claim 1 , comprising morselizing the placental membrane prior to hypothermically storing the placental membrane in the solution. 
     
     
         25 . The method according to  claim 24 , comprising adsorbing the morselized placental membrane to a mammalian collagen matrix prior to hypothermically storing the placental membrane in the solution. 
     
     
         26 . The method according to  claim 1 , comprising adding minced cartilage to the solution. 
     
     
         27 . The method according to  claim 1 , wherein the placental membrane is not frozen prior to, during or after being hypothermically stored in the solution. 
     
     
         28 . A method for treating wounds, comprising the application of tissue stored by the method according to  claim 1  and applying the tissue to the wound. 
     
     
         29 . The method according to  claim 28 , wherein the tissue is amniotic membrane. 
     
     
         30 . The method according to  claim 28 , wherein the tissue is cartilage. 
     
     
         31 . The method of according to  claim 28 , wherein the stromal surface of the tissue is applied to the wound. 
     
     
         32 . A tissue storage system comprising a placental membrane hypothermically stored within a container including a solution of DMEM and human plasma albumin. 
     
     
         33 . The system according to  claim 32 , wherein the placental membrane exhibits a ratio of live cells to dead cells greater than 1.5 following thirty-six hours of being hypothermically stored in the solution, a ratio of live cells to dead cells greater than 1.0 following one hundred twenty hours of being hypothermically stored in the solution, a ratio of live cells to dead cells greater than 2.0 following three hundred sixty hours of being hypothermically stored in the solution, a ratio of live cells to dead cells greater than about 1.5 following seven hundred twenty hours of being hypothermically stored in the solution and a ratio of live cells to dead cells of about 1.0 or more following one thousand hours of being hypothermically stored in the solution. 
     
     
         34 . The system according to  claim 32 , wherein the placental membrane has a total protein content of more than about 450 ng of protein per mg of the placental membrane following twenty-four hours of being hypothermically stored in the solution and a total protein content of more than about 300 ng of protein per mg of the placental membrane following one thousand hours of being hypothermically stored in the solution. 
     
     
         35 . The system according to  claim 32 , wherein the placental membrane has a tissue inhibiting matrix metalloproteinases 1, 2 and 4 protein content of more than 400 ng of protein per mg of the placental membrane following twenty-four hours of being hypothermically stored in the solution and a tissue inhibiting matrix metalloproteinases 1, 2 and 4 protein content of more than 250 ng of protein per mg of the placental membrane following one thousand hours of being hypothermically stored in the solution. 
     
     
         36 . The system according to  claim 35 , wherein the container includes a pair of sealed trays within which the placental membrane is situated. 
     
     
         37 . The system according to  claim 35 , wherein the placental membrane is arranged into pieces having an average particle size of less than about 1.5 mm that are adsorbed to a porous collagen matrix. 
     
     
         38 . The system according to  claim 37 , wherein the placental membrane is a meshed placental membrane. 
     
     
         39 . The system according to  claim 32 , wherein the placental membrane includes an amnion layer and a chorion layer. 
     
     
         40 . The system according to  claim 32 , wherein the placental membrane includes a spongy layer. 
     
     
         41 . The system according to  claim 32 , wherein the solution contains HEPES buffer. 
     
     
         42 . A tissue comprising:
 a placental membrane exhibiting a ratio of live cells to dead cells greater than about 1.5 following two hundred forty hours of being hypothermically stored in a solution.   
     
     
         43 . The tissue according to  claim 42  comprising a ratio of live cells to dead cells greater than about 1.5 following seven hundred twenty hours of being hypothermically stored in the solution. 
     
     
         44 . The tissue according to  claim 42 , wherein the tissue is at least partially submerged in a storage solution including DMEM and at least about 0.025% w/v human plasma albumin.