Compositions and methods for regulating NK cell activity

Abstract

The present invention relates to novel compositions and methods for regulating an immune response in a subject. More particularly, the invention relates to specific antibodies that regulate the activity of NK cells and allow a potentiation of NK cell cytotoxicity in mammalian subjects. The invention also relates to fragments and derivatives of such antibodies, as well as pharmaceutical compositions comprising the same and their uses, particularly in therapy, to increase NK cell activity or cytotoxicity in subjects.

1 . A method of producing an antibody which cross-reacts with multiple KIR2DL gene products (KIRS) and which neutralizes the inhibitory activity of such KIRs, said method comprising the steps of: 
 (a) immunizing a non-human mammal with an immunogen comprising a KIR2DL polypeptide;    (b) preparing antibodies from said immunized mammal, wherein said antibodies bind said KIR2DL polypeptide,    (c) selecting antibodies of (b) that cross-react with at least two different KIR2DL gene products,    (d) selecting antibodies of (c) that potentiate NK cells, and    (e) selecting and isolating an antibody from the antibodies of (d) that binds a primate NK cell or KIR polypeptide.    
     
     
         2 . The method of  claim 1 , wherein the primate in step (e) is a cynomolgus monkey.  
     
     
         3 . An isolated antibody, antibody fragment, or an antibody derivative comprising one or more light variable region CDRs of Pan2D as set forth in  FIG. 12 .  
     
     
         4 . The antibody, antibody fragment, or an antibody derivative of  claim 3 , wherein the antibody, antibody fragment, or antibody derivative comprises the light chain variable region sequence of Pan2D as set forth in  FIG. 12 .  
     
     
         5 . An isolated antibody, antibody fragment, or an antibody derivative comprising one or more of the light variable region CDRs of DF-200 as set forth in  FIG. 12 .  
     
     
         6 . The antibody, antibody fragment, or antibody derivative of  claim 5 , wherein the antibody, antibody fragment, or antibody derivative comprises the light chain variable region sequence of DF-200 as set forth in  FIG. 12 .  
     
     
         7 . An isolated antibody, antibody fragment, or an antibody derivative comprising one or more of the heavy variable region CDRs of DF-200 as set forth in  FIG. 13 .  
     
     
         8 . The antibody, antibody fragment, or an antibody derivative of  claim 10 , wherein the antibody, antibody fragment, or antibody derivative comprises the heavy chain variable region sequence of DF-200 as set forth in  FIG. 13 .  
     
     
         9 . An isolated antibody, antibody fragment, or antibody derivative that exclusively binds to KIR2DL1 within a region defined by amino acid residues 105, 106, 107, 108, 109, 110, 111, 127, 129, 130, 131, 132, 133, 134, 135, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 181, 192.  
     
     
         10 . An isolated antibody, antibody fragment, or antibody derivative that binds to KIR2DL1 and KIR 2DL2/3 without interacting with amino acid residues outside the region defined by residues 105, 106, 107, 108, 109, 110, 111, 127, 129, 130, 131, 132, 133, 134, 135, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 181, 192.  
     
     
         11 . An isolated antibody, antibody fragment, or antibody derivative that binds to KIR2DL1 and does not bind to a mutant of KIR2DL1 characterized by one or more of R131 is Ala, R157 is Ala, and R158 is Ala.  
     
     
         12 . An isolated antibody, antibody fragment, or antibody derivative that binds to KIR2DL1 residues 131, 157, 158.  
     
     
         13 . An isolated antibody, antibody fragment, or antibody derivative that binds to KIR2DS3(R131W), but that does not bind to wild type KIR2DS3.  
     
     
         14 . An isolated antibody, antibody fragment, or antibody derivative that binds KIR2DL1, KIR2DL2/3, and KIR2DS4.  
     
     
         15 . An isolated antibody, antibody fragment, or antibody derivative that binds to both KIR2DL1 and KIR2DL2/3, but not to KIR2DS4.  
     
     
         16 . A pharmaceutically acceptable composition comprising an effective amount of an antibody, antibody fragment, or antibody derivative according to  claim 15 .  
     
     
         17 . A pharmaceutically acceptable composition comprising an effective amount of an antibody, antibody fragment, or antibody derivative according to  claim 14 .  
     
     
         18 . A pharmaceutically acceptable composition comprising an effective amount of an antibody, antibody fragment, or antibody derivative according to  claim 3 .  
     
     
         19 . A pharmaceutically acceptable composition comprising an effective amount of an antibody, antibody fragment, or antibody derivative according to  claim 4 .  
     
     
         20 . A pharmaceutically acceptable composition comprising an effective amount of an antibody, antibody fragment, or antibody derivative according to  claim 5 .  
     
     
         21 . A pharmaceutically acceptable composition comprising an effective amount of an antibody, antibody fragment, or antibody derivative according to  claim 6 .  
     
     
         22 . A pharmaceutically acceptable composition comprising an effective amount of an antibody, antibody fragment, or antibody derivative according to  claim 7 .  
     
     
         23 . A pharmaceutically acceptable composition comprising an effective amount of an antibody, antibody fragment, or antibody derivative according to  claim 8.