Method for treating cancer using monoclonal antibodies
The invention concerns a method for obtaining and selecting monoclonal antibodies by an ADDC-type test, said antibodies capable of activating type III Fcγ receptors and having a particular glycan structure. The inventive anti-D antibodies can be used for preventing Rhesus isoimmunization in Rh negative persons, in particular for haemolytic disease in a new-born baby or for uses such as idiopathic thrombocytopenic purpura (ITP).
1. A method of treating cancer, comprising administering to a patient in need thereof a composition comprising a pharmaceutically effective amount of selected monoclonal antibodies specific to said cancer prepared by a method comprising:
A) purifying a monoclonal antibody obtained from a clone derived from a cell line selected from the group consisting of a hybridoma and an animal or human cell line transfected with a vector comprising a gene encoding said antibody,
B) adding the purified antibody to a reaction mixture comprising:
a. target cells for said purified antibody,
b. effector cells comprising cells expressing FcγRIII, and
c. polyvalent IgGs, and
C) determining a lysis percentage of the target cells and selecting monoclonal antibodies that activate the effector cells and causes a significant lysis of the target cells (FcγRIII-type ADCC activity) to yield the selected monoclonal antibodies.
2. The method of claim 1 , wherein the cell line is obtained by fusing human B lymphocytes originating from an immunized individual with murine, humans or heterohybrid myeloma cells.
3. The method of claim 2 , wherein the heterohybrid myeloma cells are K6H6-B5 myeloma cells (ATCC No. CRL 1823).
4. A method of treating cancer comprising administering to a patient in need thereof a monoclonal antibody composition specific to said cancer, wherein said composition comprises purified monoclonal antibodies having on Fcγ glycosylation site (Asn 297, EU numbering) bi-antennary glycan structures,
wherein said glycan structures of the purified monoclonal antibodies have a fucose content less than 65%, and
wherein said glycan structures of the purified monoclonal antibodies have a content greater than 60% for the G0+G1+G0F+G1F forms
5. The method of claim 4 , wherein the fucose content is less than 30%.
6. The method of claim 4 , wherein the fucose content is between 20% and 45%.
7. The method of claim 4 , wherein the fucose content is between 25% and 40%.
8. The method of claim 4 , wherein the purified monoclonal antibodies are directed against an antigen, and activate effector cells expressing Fcγ type III receptors, causing a lysis of target cells presenting the antigen greater than 60% of a lysis caused by polyclonal antibodies directed against the antigen.
9. The method of claim 4 , wherein the purified monoclonal antibodies are directed against an antigen, and activate effector cells expressing Fcγ type III receptors, causing a lysis of target cells presenting the antigen greater than 90% of a lysis caused by polyclonal antibodies directed against the antigen.
10. The method of claim 4 , wherein the purified monoclonal antibodies are IgG1 antibodies.
11. The method of claim 4 , wherein the purified monoclonal antibodies are IgG3 antibodies.
12. The method of claim 4 , wherein said glycan structures of the purified monoclonal antibodies have a sialic acid content of less than 25%.
13. A method of treating cancer comprising administering to a patient in need thereof a monoclonal antibody composition specific to said cancer, wherein said composition comprises purified monoclonal antibodies having on the Fcγ glycosylation sites (Asn 297, EU numbering) bi-antennary glycan structures,
wherein said glycan structures of the purified monoclonal antibodies have a content less than 50% for the G0F+G1F forms, and
wherein said glycan structures of the purified monoclonal antibodies have a content greater than 60% for the G0+G1+G0F+G1F forms.
14. The method of claim 13 , wherein said glycan structures of the purified monoclonal antibodies have a content less than 30% for the G0F+G1F forms.
15. The method of claim 13 , wherein said glycan structures of the purified monoclonal antibodies have a content greater than 80% for the G0+G1+G0F+G1F forms.
16. The method of claim 13 , wherein the monoclonal antibodies are directed against an antigen, and activate effector cells expressing Fcγ type III receptors, causing a lysis of target cells presenting the antigen greater than 60% of a lysis caused by polyclonal antibodies directed against the antigen.
17. The method of claim 16 , wherein the monoclonal antibodies cause a lysis of target cells presenting the antigen greater than 70% of a lysis caused by polyclonal antibodies directed against the antigen.
18. The method of claim 17 , wherein the monoclonal antibodies cause a lysis of target cells presenting the antigen greater than 80% of a lysis caused by polyclonal antibodies directed against the antigen.
19. The method of claim 18 , wherein the monoclonal antibodies cause a lysis of target cells presenting the antigen greater than 90% of a lysis caused by polyclonal antibodies directed against the antigen.
20. The method of claim 13 , wherein said monoclonal antibodies are IgG1 antibodies.
21. The method of claim 13 , wherein said monoclonal antibodies are IgG3 antibodies.
22. The method of claim 13 , wherein said glycan structures of the purified monoclonal antibodies have a sialic acid content of less than 25%.