Chondrocyte cell-lines

Abstract

The invention relates to chondrocytes and chondrocyte cell-lines for use especially in studying arthritic conditions and also for developing skeletal tissue for use in repair and/or replacement surgery. The use of articular chondrocyte cell-lines which mineralise calcium to determine potentially beneficial therapeutic agents is disclosed. Further, the means for producing such cell-lines is also disclosed as well as the characteristics of such cell-lines. The use of hypertrophic chondrocyte cell-lines to produce matrix tissue is also disclosed. Further means of producing hypertrophic chondrocyte cell-lines is also disclosed as well as the charateristics of such cell-lines.

1 . An isolated articular chondrocyte which is characterized in that it mineralizes calcium.  
     
     
         2 . An articular chondrocyte of  claim 1  wherein a plurality of such chondrocytes are arranged in pellet form.  
     
     
         3 . An articular chondrocyte of  claim 1  wherein said chondrocyte is mature or derived from a mature individual and preferably an individual suffering from or having a predisposition for arthritis.  
     
     
         4 . An articular chondrocyte of  claim 1  wherein said chondrocyte is of fetal origin.  
     
     
         5 . An articular chondrocyte of  claim 1  wherein said chondrocyte is provided as a cell-line.  
     
     
         6 . An articular chondrocyte of  claim 5  wherein said cell-line is of human origin.  
     
     
         7 . An articular chondrocyte of  claim 1  wherein said chondrocyte comprises an oncogene.  
     
     
         8 . An articular chondrocyte of  claim 7  wherein said oncogene is temperature sensitive.  
     
     
         9 . An articular chondrocyte of  claim 8  wherein said oncogene is an SV40 T antigen.  
     
     
         10 . A method for producing an articular chondrocyte cell-line that mineralizes calcium comprising. 
 a) immortalizing at least one human articular chondrocyte cell using an immortalizing agent; and    b) culturing said immortalized cell in order to produce a population of human articular chondrocyte cells.    
     
     
         11 . A method of  claim 10  wherein said immortalizing agent is an oncogene.  
     
     
         12 . A method of  claim 11  wherein said oncogene is temperature sensitive.  
     
     
         13 . A method of  claim 12  wherein said oncogene is SV40 T antigen.  
     
     
         14 . A method of  claim 12  wherein the method further comprises the step of culturing said immortalized cell at the non-permissive temperature of the oncogene.  
     
     
         15 . A method for identifying a therapeutic agent designed to treat arthritis comprising: 
 a) exposing isolated chondrocytes, or at least one chondrocyte cell-line, comprising articular chondrocytes that mineralize calcium to at least one test agent;    b) observing the nature of the response to said test agent; and    c) identifying any agent showing a response useful for treating arthritist.    
     
     
         16 . A method of  claim 15  wherein said observation involves an assessment of the amount of calcium mineralization associated with said chondrocytes or said chondrocyte cell-line.