Alginate capsules for use in the treatment of brain tumour

Abstract

Encapsulated producer cells which are capable of expressing a molecule which is an inhibitor of CNS tumour growth provide a novel approach to the treatment of tumours, such as brain tumours which are localized within the central nervous system.

1 - 19 . (canceled)  
     
     
         20 . A composition comprising a producer cell that expresses a molecule that is an inhibitor of the growth of a CNS tumor, the cell being encapsulated in a matrix that comprises an immunoisolating alginate having a G contant of above 15%, wherein the molecule is a monoclonal antibody that interacts directly with an antigen of the CNS tumor.  
     
     
         21 . The composition of  claim 20  wherein the monoclonal antibody interacts directly with an antigen of the CNS tumor selected from the group consisting of platelet derived growth factor receptors AA and BB, acidic and basic fibroblast growth factor receptors, transforming growth factor receptors alpha and beta, vascular endothelial growth factor receptors, tyrosine kinase receptors with immunoglobulin-like and EGF-like domains, hepatocyte growth factor, CD-44, CDR/cyclin complexes, glycolipids on the cell surface, glycoproteins, and proteins derived from the expression of oncogenes.  
     
     
         22 . The composition according to  claim 20 , wherein the alginate has a G content of above 50%.  
     
     
         23 . The composition according to  claim 20 , wherein the alginate has a G content of 60% to 80%.  
     
     
         24 . The composition according to  claim 20 , wherein the alginate has a G content of 80% to 100%.  
     
     
         25 . The composition according to  claim 20 , wherein the producer cell's expression of the molecule is switched on and off by an external pharmacological agent.  
     
     
         26 . The composition according to  claim 20 , wherein the producer cell is encapsulated in a bead or microbead.  
     
     
         27 . The composition according to  claim 26 , wherein the alginate concentration within the bead or microbead increases from the center of the bead or the microbead to the outer rim.  
     
     
         28 . The composition according to  claim 20 , wherein the CNS tumor is a brain tumor.  
     
     
         29 . The composition according to  claim 20 , wherein the alginate is substantially free of endotoxin.  
     
     
         30 . A method of producing the composition according to  claim 20 , comprising introducing a mixture of the producer cells and the alginate into a solution containing multivalent cations.  
     
     
         31 . A method of producing the composition according to  claim 20 , comprising the step of adding, in a drop-wise manner, an alginate solution containing at least one viable cell to a calcium-containing solution.  
     
     
         32 . A pharmaceutical composition comprising the composition according to  claim 20  and a pharmaceutically acceptable carrier or diluent.  
     
     
         33 . A method of treating a mammalian patient afflicted with a CNS tumor comprising the step of directly administering to the CNS tumor or the site of tumor resection an amount of the pharmaceutical composition according to  claim 32  effective to inhibit growth or regrowth of said tumor.  
     
     
         34 . The method of  claim 33 , wherein the CNS tumor is a brain tumor.