Antibodies with altered effector functions

• US 5,624,821 A
• Filed: 06/07/1995
• Issued: 04/29/1997
• Est. Priority Date: 03/18/1987
• Status: Expired due to Term

• Current Assignee: SB2 Incorporated
• Original Assignee: Scotgen Biopharmaceuticals, Inc.
• Inventors: Burton, Dennis R., Duncan, Alexander R., Winter, Gregory P.
• Primary Examiner(s): Feisee, Lia
• Assistant Examiner(s): Reeves, Julie E.
• Application Number:
  US08/479,752
• Time in Patent Office: 692 Days
• Field of Search: 530/387.3, 424/133.1, 435/69.6, 435/172.3, 435/252.3
• US Class Current: 435/69.6
• CPC Class Codes: C07K 16/00 Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies antibodies with enzymatic activity, e.g. abzymes C12N9/0002

Abstract

An antibody with an altered function, e.g. altered affinity for an effector ligand such as Fc receptor (FcR) on a cell or the C1 component of complement is produced by replacing at least one amino acid residue in the constant portion of the antibody with a different residue.

Claims

1. A modified antibody of class IgG, in which at least one amino acid from the heavy chain constant region selected from the group consisting of amino acid residues 234, 235, 236, 237, 297, 318, 320 and 322 is substituted with another amino acid which is different from that present in an unmodified antibody, thereby causing an alteration in an effector function while retaining binding to antigen as compared with the unmodified antibody.

2. The modified antibody according to claim 1, in which at least one amino acid from the heavy chain constant region selected from the group consisting of amino acid residues 234, 235, 236 and 237 is substituted with an amino acid which is different from that present in an unmodified antibody, thereby causing an alteration in binding affinity for a Fc receptor as compared with the unmodified antibody.

3. The modified antibody according to claim 2, having a reduced binding affinity for Fc gamma RI receptor as compared with unmodified antibody.

4. The modified antibody according to claim 2, wherein at least one amino acid from the heavy chain constant region selected from the group consisting of amino acid residues 234, 236 and 237 is substituted with alanine.

5. The modified antibody according to claim 2, wherein amino acid residue 235 from the heavy chain constant region is substituted with glutamine.

6. The modified antibody according to claim 1, in which amino acid residue 297 from the heavy chain constant region is substituted with an amino acid which is different from that present in an unmodified antibody, thereby causing a reduction in lytic properties as compared with the unmodified antibody.

7. The modified antibody according to claim 6, wherein amino acid 297 from the heavy chain constant region is substituted with alanine.

8. The modified antibody according to claim 1, in which at least one amino acid from the heavy chain constant region selected from the group consisting of amino acid residues 318, 320 and 322 is substituted with an amino acid which is different from that present in an unmodified antibody, thereby causing a reduction in binding affinity for Clq as compared with the unmodified antibody.

9. The modified antibody according to claim 8, wherein at least one amino acid from the heavy chain constant region selected from the group consisting of amino acid residues 318, 320 and 322 is substituted with alanine, thereby reducing Clq binding affinity.

10. The modified antibody according to claim 8, wherein amino acid residue 318 from the heavy chain constant region has been substituted with valine.

11. The modified antibody according to claim 8, wherein amino acid residue 322 from the heavy chain constant region is substituted with glutamine.

12. The modified antibody according to claim 1, comprising rodent or human IgG.

13. The modified antibody according to claim 1, wherein the unmodified antibody is a naturally occurring antibody, or a recombinantly altered antibody.

14. A process for modifying an antibody of class IgG, comprising substituting at least one amino acid from the heavy chain constant region selected from the group consisting of amino acid residues 234, 235, 236, 297, 318, 320 and 322 with an amino acid which is different from that present in an unmodified antibody, thereby altering an affinity for a effector molecule while retaining binding to antigen as compared with the affinity of the unmodified antibody.

15. A method of producing modified antibody of class IgG with an altered effector function as compared with unmodified antibody comprising:

.

(a) preparing a replicable expression vector comprising a suitable promoter operably linked to a DNA which encodes at least part of a constant region of an immunoglobulin heavy chain and in which at least one amino acid from the heavy chain constant region selected from the group consisting of amino acid residues 234, 235, 236, 237, 297, 318, 320 and 322 is substituted with an amino acid which is different from that present in an unmodified antibody thereby causing an alteration in an effector function while retaining binding to antigen as compared with the unmodified antibody;

(b) transforming a cell line with said vector; and

(c) culturing said transformed cell line to produce said modified antibody.

16. The method according to claim 15 further comprising after step (a):

preparing a second replicable expression vector comprising a promoter operably linked to a DNA which encodes a complementary immunoglobulin light chain and wherein said cell line is further transformed with said vector.

17. The method according to claim 15, wherein the constant region of an immunoglobulin heavy chain has at least one amino acid selected from the group consisting of amino acid residues 234, 235, 236 and 237 substituted with an amino acid which is different from that present in an unmodified antibody, thereby causing an alteration in binding affinity for a Fc receptor as compared with the unmodified antibody.

18. The method according to claim 15, wherein said constant region of an immunoglobulin heavy chain has amino acid residue 297 substituted with an amino acid which is different from that present in an unmodified antibody, thereby causing a reduction in lytic properties as compared with the unmodified antibody.

19. The method according to claim 15, wherein said constant region of an immunoglobulin heavy chain has at least one amino acid selected from the group consisting of amino acid residues 318, 320 and 322 substituted with an amino acid which is different from that present in an unmodified antibody, thereby causing a reduction in binding affinity for Clq as compared with the unmodified antibody.

20. The method of claim 17, wherein at least one amino acid from the heavy chain constant region selected from the group consisting of amino acid residues 234, 236 and 237 is substituted with alanine.

21. The method of claim 17, wherein amino acid residue 235 from the heavy chain constant region is substituted with glutamine.

22. The method of claim 18, wherein amino acid 297 from the heavy chain constant region is substituted with alanine.

23. The method of claim 19, wherein at least one amino acid from the heavy chain constant region selected from the group consisting of amino acid residues 318, 320 and 322 is substituted with alanine, thereby reducing Clq binding affinity.

24. The method of claim 19, wherein amino acid residue 318 from the heavy chain constant region has been substituted with valine.

25. The method of claim 19, wherein amino acid residue 322 from the heavy chain constant region is substituted with glutamine.