Monoclonal antibodies to stem cell factor receptors

Abstract

The present invention relates to monoclonal antibodies specific for a cell receptor specific for human stem cell factor (hSCF) as well as pharmaceutical compositions containing such monoclonal antibodies and uses of such monoclonal antibodies.

What is claimed is:  
     
         1 . A monoclonal antibody comprising a monoclonal antibody having an ability to bind to an SCF receptor.  
     
     
         2 . A monoclonal antibody according to  claim 1  wherein said SCF receptor is a human SCF receptor.  
     
     
         3 . A monoclonal antibody according to  claim 2  wherein said monoclonal antibody is SR-1.  
     
     
         4 . A monoclonal antibody according to  claim 1  further comprising an ability to inhibit binding of a SCF molecule to said SCF receptor.  
     
     
         5 . A monoclonal antibody according to  claim 4  wherein said SCF molecule is a human SCF molecule.  
     
     
         6 . A monoclonal antibody according to  claim 5  wherein said SCF receptor is a human SCF receptor.  
     
     
         7 . A method of purifying hematopoietic cells comprising the steps of: 
 (a) exposing a mixture of cells to a monoclonal antibody according to  claim 1;     (b) separating cells that bind to said monoclonal antibody from cells that do not bind to said monoclonal antibody.    
     
     
         8 . A method of purifying hematopoietic cells according to  claim 7  wherein said separating is by column chromatography.  
     
     
         9 . A method of purifying hematopoietic cells according to  claim 7  wherein said separating is by fluorescence-activated cell sorting.  
     
     
         10 . A method of purifying hematopoietic cells according to  claim 7  wherein said separating is by direct immune adherence.  
     
     
         11 . A method of reconstituting hematopoietic cells comprising bone marrow transplantation with hematopoietic cells purified according to the method of  claim 7 .  
     
     
         12 . A method of gene therapy comprising retrovirally-mediated gene transfer into cells purified according to  claim 7 .  
     
     
         13 . A method of separating normal cells from neoplastic leukemia cells comprising the steps of: 
 (a) exposing a mixture of cells comprising normal cells and neoplastic leukemia cells to a monoclonal antibody according to  claim 1;     (b) separating normal cells from neoplastic leukemia cells based upon a differential in numbers of SCF receptors on normal cells and neoplastic leukemia cells.    
     
     
         14 . A method of treating leukemia cells comprising administration of a therapeutically effective amount of a leukemia therapeutic agent conjugated to a monoclonal antibody according to  claim 1 .  
     
     
         15 . A method of treating leukemia cells comprising administration of a therapeutically effective amount of a leukemia therapeutic agent conjugated to a binding fragment of a monoclonal antibody according to  claim 1 .  
     
     
         16 . A method of treating solid tumors comprising administration of a therapeutically effective amount of a solid tumor therapeutic agent conjugated to a monoclonal antibody according to  claim 1 .  
     
     
         17 . A method of treating solid tumors comprising administration of a therapeutically effective amount of a solid tumor therapeutic agent conjugated to a binding fragment of a monoclonal antibody according to  claim 1 .  
     
     
         18 . A method of determining the presence of SCF receptors in a cell sample comprising the steps of: 
 (a) exposing a cell sample to a monoclonal antibody according to  claim 1;     (b) detecting the binding of said monoclonal antibody to SCF receptors.    
     
     
         19 . A method according to  claim 18  wherein said detecting is accomplished by using a labelled monoclonal antibody.  
     
     
         20 . A method according to  claim 18  wherein said cell sample is selected from the group consisting of normal cells, leukemia cells and solid tumor cells.  
     
     
         21 . A method of modifying sensitivity to cell cycle-specific chemotherapeutic agents comprising administration of a SCF inhibiting amount of a monoclonal antibody according to  claim 1 .  
     
     
         22 . A monoclonal antibody according to  claim 1  wherein said monoclonal antibody is a murine-human hybrid antibody.  
     
     
         23 . A monoclonal antibody according to  claim 1  wherein said antibody is of the IgG2a isotype.  
     
     
         24 . A hybridoma capable of producing a monoclonal antibody according to  claim 1 .  
     
     
         25 . A hybridoma according to  claim 24  wherein said hybridomas is capable of producing the monoclonal antibody SR-1.