In vivo, ex vivo and in vitro regenerated cartilage

Abstract

A method for in vivo, ex vivo and in vitro regeneration of cartilage and collagen. In vivo, ex vivo and in vitro regeneration and de novo formation of articular cartilage and collagen by intermittently applied hydrostatic pressure. The application of external interval loading consisting of repeated periods of applied hydrostatic pressure followed and interrupted by periods of recovery. The application of the intermittent hydrostatic pressure at physiological levels 5-10 MPA for an interval of 4 hours followed by a recovery period up to about 20 hours, said pressure applied to the cartilage cells in vitro, explants of cartilage ex vivo and in vivo to cartilage that remains intact within te joint space of diarthrotic joints. The interval loading results in the selective inhibition of matrix degrading enzymes, pro-inflammatory cytokines and chemokines that attract inflammatory cells into the joint cavity and in selective decrease of gene expression of growth factors that are inhibitory to type II collagen expression.

What is claimed  
     
         1 . A method for repair and regeneration of degenerated, diseased or injured articular cartilage or for de novo production of cartilage, collagen, ligaments or tendons, said method comprising a step of subjecting the degenerated, diseased or injured cartilage, a cartilage graft or healthy chondrocytes or other mesenchymally-derived cells to intermittently applied hydrostatic pressure between about 0.5 and about 30 MPA for about 2 to about 8 hours daily followed by about 16 to 22 hours recovery period for period of about 4 to about 100 days or as needed.  
     
     
         2 . The method of  claim 1  wherein the pressure is applied at frequency of about 0.1-10 Hz.  
     
     
         3 . The method of  claim 2  wherein the de novo method comprises loading a matrix with a suspension of mesenchymal or mesenchymally-derived cells.  
     
     
         4 . The method of  claim 2  wherein the pressure is between about 1 MPA and about 10 MPA pressure is applied intermittently for about 4 hours and the recovery period is about 20 hours.  
     
     
         5 . The method of  claim 4  wherein the pressure is about 5 MPa-10 MPA.  
     
     
         6 . The method of  claim 5  wherein the cartilage is subjected to the intermittent hydrostatic pressure (IHP) in situ using an external device to apply such pressure.  
     
     
         7 . The method of  claim 5  wherein the cartilage is subjected to the IHP ex Vivo and following the regeneration is returned to a treated joint.  
     
     
         8 . The method of  claim 5  wherein the cartilage is regenerated in vitro by submitting a cartilage chondrocyte to IHP.  
     
     
         9 . A method for restoration of function of degenerated, diseased or injured joint, said method comprising step of subjecting the degenerated, diseased or injured cartilage or a cartilage graft removed from the joint or a healthy chondrocytes to intermittently applied hydrostatic pressure between about 0.5 and about 30 MPA for about 1 to about 8 hours daily followed by about 16 to 22 hours recovery period for period of about 4 to about 100 days or as needed.  
     
     
         10 . The method of  claim 9  wherein the pressure is applied at frequency of about 0.1-10 Hz.  
     
     
         11 . The method of  claim 10  wherein the restoration of the joint is implanting a matrix comprising healthy chondrocytes.  
     
     
         12 . The method of  claim 11  wherein the pressure is between about 1 and about 10 MPA and the pressure is applied intermittently for about 4 hours and the recovery period is about 20 hours.  
     
     
         13 . The method of  claim 12  wherein the pressure is about 5 MPA-10 MPA.  
     
     
         14 . The method of  claim 13  wherein the cartilage is subjected to the intermittent hydrostatic pressure (IHP) in situ using an external device to apply such pressure.  
     
     
         15 . The method of  claim 14  wherein the cartilage is subjected to the IHP ex vivo and following the regeneration is returned to a treated joint.  
     
     
         16 . The method of  claim 15  wherein the cartilage is regenerated in vitro by submitting a cartilage chondrocyte to IHP.  
     
     
         17 . The method of  claim 1  wherein the disease is osteoarthritis and osteoarthrosis.  
     
     
         18 . The method of  claim 1  wherein the degeneration is degenerative joint disease.  
     
     
         19 . The method of  claim 1  wherein the disease is a collagen deficiency.  
     
     
         20 . The method of  claim 1  wherein the joint injury is loaded or damaged cartilage.  
     
     
         21 . A cartilage regenerated to its mechanical and biochemical functionality by submitting a degenerated or diseased or injured cartilage or cartilage graft to intermittently applied hydrostatic pressure between about 0.5 and about, 30 MPA for about 1 to about 8 hours daily followed by about 16 to 22 hours recovery period for period of about 4 to about 100 days.  
     
     
         22 . The method of  claim 1  wherein the pressure is applied at frequency of about 1 Hz.  
     
     
         23 . The cartilage of  claim 2  wherein the pressure is applied intermittently for about 4 hours and the recovery period is about 20 hours.  
     
     
         24 . The method of  claim 3  wherein the pressure is between about 0.1 and about 10 MPA.  
     
     
         25 . The method of  claim 4  wherein the pressure is about 5 MPA-10 MPA.  
     
     
         26 . The method of  claim 5  wherein the cartilage is subjected to the intermittent hydrostatic pressure (IHP) in situ using an external device to apply such pressure.  
     
     
         27 . The method of  claim 5  wherein the cartilage is subjected to the IHP ex vivo and following the regeneration is returned to a treated joint.  
     
     
         28 . The method of  claim 5  wherein the cartilage is regenerated in vitro by submitting a cartilage chondrocyte to IHP.  
     
     
         29 . A method for determination of functionality or extent of injury of cartilage following IHP treatment or collagen by determining a level of expression of mRNA of collagen, mRNA aggrecan, TGF, MMP-1, MMP-2 or IL-6.