Anti-ganglioside antibodies and compositions
IgM can be obtained in the form of a pentamer by placing the genes encoding the H, L, and J chains on the same vector to transform appropriate host cells. The gene encoding the J chain may be introduced by co-transfection. When no J chain is expressed, the IgM is produced as a hexamer. The transformants obtained according to the present invention achieve a high yield of IgM. The present invention also provides methods which enable separation and quantification of polymeric IgM.
1. A pharmaceutical composition comprising a substantially purified anti-ganglioside GM3 IgM antibody, wherein said IgM antibody
(a) has a heavy (H) chain comprising SEQ ID NO: 2 and a light (L) chain comprising SEO ID NO: 4, and
(b) is recombinantly produced in a non-lymphoid cell.
2. The pharmaceutical composition of claim 1 comprising 80% or more pentamer IgM.
3. The pharmaceutical composition of claim 1 comprising 50% or more hexamer IgM.
4. The pharmaceutical composition of claim 3 , comprising 80% or more hexamer IgM.
5. The pharmaceutical composition of claim 1 comprising IgM having a hexamer/pentamer ratio of at least 1.5.
6. The pharmaceutical composition of claim 1 , wherein the non-lymphoid cell is a CHO cell.
7. The pharmaceutical composition of claim 1 , wherein the IgM is produced by a method comprising
(a) culturing transformed non-lymphoid cells so that they produce the IgM at a level of at least 100 mg/L or at a level of at least 35 pg/cell/day, and
(b) collecting the IgM from the culture or a supernatant of the culture.
8. The pharmaceutical composition of claim 1 , wherein the substantially pure IgM is obtained by purifying the IgM from a culture supernatant obtained from culturing transformed non-lymphoid cells producing the IgM at a level of at least 100 mg/L or at a level of at least 35 pg/cell/day.
9. The pharmaceutical composition of claim 1 , wherein the IgM antibody is produced in the absence of IgM J chain.
10. The pharmaceutical composition of claim 1 , wherein the IgM antibody is produced in the presence of IgM J chain.
11. A pharmaceutical composition comprising a substantially purified anti-ganglioside GM2 IgM antibody, wherein said IgM antibody
(a) has a heavy (H) chain comprising SEQ ID NO: 20 and a light (L) chain comprising SEQ ID NO: 22, and
(b) is recombinantly produced in a non-lymphoid cell.
12. The pharmaceutical composition of claim 11 comprising 80% or more pentamer IgM.
13. The pharmaceutical composition of claim 11 comprising 50% or more hexamer IgM.
14. The pharmaceutical composition of claim 13 , comprising 80% or more hexamer IgM.
15. The pharmaceutical composition of claim 11 comprising IgM having a hexamer/pentamer ratio of at least 1.5.
16. The pharmaceutical composition of claim 11 , wherein the non-lymphoid cell is a CHO cell.
17. The pharmaceutical composition of claim 11 , wherein the IgM is produced by a method comprising
(a) culturing transformed non-lymphoid cells so that they produce the IgM at a level of at least 100 mg/L or at a level of at least 35 pg/cell/day, and
(b) collecting the IgM from the culture or a supernatant of the culture.
18. The pharmaceutical composition of claim 11 , wherein the substantially pure IgM is obtained by purifying the IgM from a culture supernatant obtained from culturing transformed non-lymphoid cells producing the IgM at a level of at least 100 mg/L or at a level of at least 35 pg/cell/day.
19. The pharmaceutical composition of claim 11 , wherein the IgM antibody is produced in the absence of IgM J chain.
20. The pharmaceutical composition of claim 11 , wherein the IgM antibody is produced in the presence of IgM J chain.