Tissue patch

Abstract

Tissue patches and associated systems and methods are described. Certain embodiments are related to inventive systems and methods in which tissue patches can be made quickly and robustly without the use of complicated fabrication or sterilization equipment. For example, in some embodiments, tissue patches are made by applying a compressive force to a liquid medium comprising fibrinogen (and/or fibrin) between two surfaces (e.g., within a syringe or other chamber). A filter can be placed within or near the volume in which the compressive force is applied to the liquid medium such that unwanted material (e.g., water, blood cells, and the like) is passed through the filter while desirable components (e.g., fibrin, fibrinogen, and/or other desirable components) are retained by the filter to form the patch. In this way, the concentration of fibrin (and/or fibrinogen) within the liquid medium can be increased, potentially dramatically, as the compressive force is applied to the liquid-containing composition. In addition, in some embodiments, at least a portion of the fibrinogen and/or fibrin can chemically react (e.g., the fibrinogen can polymerize to form fibrin and/or the fibrin can cross-link) during application of the compressive force. Reaction and concentration can lead to the formation of a highly-concentrated, mechanically robust patch that can be handled relatively easily and provide good structural reinforcement at a wet site, such as a bleeding wound.

What is claimed is: 
     
         1 . (canceled) 
     
     
         2 . A patch, comprising:
 a primer region comprising a water-activated polymeric adhesive; and   a solid matrix positioned over at least a portion of the primer region,   wherein:
 the water-activated polymeric adhesive comprises one or more polymers of acrylic acid cross-linked with a polyalkenyl ether and/or a divinyl alcohol; and 
 the patch is configured for application to a tissue surface. 
   
     
     
         3 . The patch of  claim 2 , wherein the solid matrix comprises fibrin. 
     
     
         4 . The patch of  claim 2 , wherein the solid matrix is an unsupported solid matrix. 
     
     
         5 . The patch of  claim 2 , wherein the solid matrix comprises a cross-linked network of fibrin. 
     
     
         6 . The patch of  claim 2 , wherein the water-activated polymeric adhesive is present within the primer region in an amount of from about 5 wt % to about 50 wt %. 
     
     
         7 . The patch of  claim 2 , wherein the patch optionally further comprises fibrinogen, and the sum of a concentration of the fibrin in the matrix and a concentration of the optional fibrinogen within the matrix is at least about 10 grams per liter of the matrix. 
     
     
         8 . A method of treatment of an animal or human subject, comprising:
 applying the patch of  claim 2  to tissue of the subject to inhibit bleeding, reinforce the tissue, at least partially fill a void within the tissue, and/or to at least partially seal a leak within the tissue.   
     
     
         9 . The method of  claim 8 , wherein the tissue is spleen tissue. 
     
     
         10 . The method of  claim 8 , wherein the tissue is lung tissue. 
     
     
         11 . A method, comprising:
 applying a compressive force to a composition comprising water and fibrin and/or fibrinogen such that at least a portion of the water is passed through a filter to create a matrix retained by the filter that is concentrated in fibrin and/or fibrinogen relative to the composition; and   forming a cross-linked fibrin matrix by:
 cross-linking at least a portion of the fibrin from the composition, and/or 
 cross-linking fibrin formed from polymerization of at least a portion of the fibrinogen from the composition, 
   wherein the cross-linked fibrin matrix has at least one cross-sectional dimension of at least about 1 cm.   
     
     
         12 . The method of  claim 11 , wherein the cross-linked fibrin matrix has a thickness of between about 500 microns and about 1 cm. 
     
     
         13 . The method of  claim 12 , wherein the cross-linked fibrin matrix has a maximum cross-sectional diameter orthogonal to the thickness that is at least about 1 cm. 
     
     
         14 . The method of  claim 11 , wherein the composition comprises whole blood. 
     
     
         15 . The method of  claim 11 , wherein the composition comprises a plasma component of whole blood. 
     
     
         16 . The method of  claim 11 , wherein the applying comprises applying the compressive force to a chamber containing the composition. 
     
     
         17 . The method of  claim 16 , wherein the chamber comprises at least one wall that is moveable to reduce the volume of the chamber. 
     
     
         18 . The method of  claim 17 , wherein the chamber comprises a stop configured to prevent the moveable wall from reducing the volume of the chamber below a threshold value. 
     
     
         19 . The method of  claim 16 , wherein the chamber is part of a syringe. 
     
     
         20 . A kit, comprising:
 a syringe configured to receive a quantity of a composition comprising water and fibrin and/or fibrinogen;   a filter configured to separate at least a portion of the fibrin and/or the fibrinogen within the composition from at least a portion of the water within the composition; and   a curing agent capable of activating the cross-linking of fibrin.