IgE anti-HMW-MAA antibody
In one aspect, there is provided an antibody or a functional fragment thereof, wherein the antibody or functional fragment thereof is capable of binding specifically to high molecular weight melanoma associated antigen (HMW-MAA), and binding to an Fcε receptor.
1. An IgE antibody, wherein the antibody is capable of:
(a) binding specifically to high molecular weight melanoma associated antigen (HMW-MAA); and
(b) binding to an Fcε receptor,
wherein the antibody comprises heavy chain CDR sequences of SEQ ID NO: 18, SEQ ID NO: 19 and SEQ ID NO: 20 and light chain CDR sequences of SEQ ID NO: 21, SEQ ID NO: 22 and SEQ ID NO: 23, and the heavy chain CDR sequence of SEQ ID NO:19 contains a conservative amino acid substitution of Asparagine (N) to Glutamine (Q).
2. The antibody of claim 1 , wherein the antibody comprises one or more constant regions capable of binding to an Fcε receptor.
3. The antibody of claim 1 , wherein the antibody has framework regions or constant domains that are derived from a mammalian species other than a mouse.
4. The antibody or functional fragment thereof of claim 3 , wherein the framework regions or constant domains are derived from a human.
5. The antibody of claim 1 , comprising one or more heavy chain constant domains selected from the group consisting of Cε1, Cε2, Cε3, and Cε4.
6. The antibody of claim 1 , wherein the antibody or functional fragment thereof comprises an ε heavy chain.
7. The antibody of claim 1 , wherein the antibody is conjugated to a detectable label, or a therapeutic agent, a cytotoxin, an encapsulating agent or a radioactive moiety.
8. The antibody of claim 1 , wherein the antibody comprises
(i) a VH domain comprising SEQ ID NO:4, and the VH domain contains a conservative amino acid substitution of Asparagine (N) to Glutamine (Q) in the heavy chain CDR sequence of SEQ ID NO: 19;
or
(ii) a VL domain comprising SEQ ID NO:6.
9. The antibody of claim 1 , wherein the antibody comprises
(i) a VH domain comprising SEQ ID NO:7, and the VH domain contains a conservative amino acid substitution of Asparagine (N) to Glutamine (Q) in the heavy chain CDR sequence of SEQ ID NO: 19;
or
(ii) a light chain comprising the amino acid sequence as defined in SEQ ID NO:8.
10. The antibody of claim 1 , wherein the conservative amino acid substitutions do not substantially affect or decrease affinity of the antibody to HMW-MAA and/or Fcε receptors.
11. The antibody of claim 1 , wherein the conservative amino acid substitution comprises exchange of Asparagine (N) to Glutamine (Q) at position 6 of SEQ ID NO:19.
12. A pharmaceutical composition comprising the antibody of claim 1 , and a pharmaceutically acceptable carrier.
13. A method of treating malignant melanoma in a subject, comprising administering to the subject a therapeutically effective amount of the pharmaceutical composition of claim 12 , wherein the malignant melanoma expresses HMW-MAA.