Antibody for neutralizing substance having coagulation factor viii (f.viii) function-substituting activity
Production was attempted for antibodies that neutralize the activity of a bispecific antibody having F.VIII function-substituting activity, for use in a method for measuring the reactivity of F.VIII in the presence of a bispecific antibody having F.VIII function-substituting activity. As a result, it was discovered that by using the produced antibodies, F.VIII activity in the plasma of a hemophilia A patient can be evaluated accurately by performing APTT-based one-stage clotting assay on a wide range of bispecific antibodies having F.VIII function-substituting activity. It was also discovered that F.VIII inhibitor titer in the plasma of a hemophilia A patient carrying F.VIII inhibitor can be evaluated accurately by APTT-based Bethesda assay.
1 . An antibody that comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 1 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 2.
2 . An antibody that comprises an antibody heavy chain comprising the amino acid sequence of SEQ ID NO: 131 and an antibody light chain comprising the amino acid sequence of SEQ ID NO: 132.
3 . An antibody that comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 3 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 4.
4 . An antibody that comprises an antibody heavy chain comprising the amino acid sequence of SEQ ID NO: 135 and an antibody light chain comprising the amino acid sequence of SEQ ID NO: 136.
5 . A composition comprising the antibody of claim 1 .
6 . A composition comprising the antibody of claim 2 .
7 . A composition comprising the antibody of claim 3 .
8 . A composition comprising the antibody of claim 4 .
9 . A kit for measuring the reactivity of coagulation factor VIII, wherein the kit comprises the composition of claim 5, 6, 7, or 8 .
10 . An antibody comprising:
a heavy chain variable region that comprises a CDR1 consisting of the amino acid sequence of SEQ ID NO: 12, a CDR2 consisting of the amino acid sequence of SEQ ID NO: 13, and a CDR3 consisting of the amino acid sequence of SEQ ID NO: 14, and
a light chain variable region that comprises a CDR1 consisting of the amino acid sequence of SEQ ID NO: 18, a CDR2 consisting of the amino acid sequence of SEQ ID NO: 19, and a CDR3 consisting of the amino acid sequence of SEQ ID NO: 20.
11 . An antibody comprising:
a heavy chain variable region that comprises a CDR1 consisting of the amino acid sequence of SEQ ID NO: 24, a CDR2 consisting of the amino acid sequence of SEQ ID NO: 25, and a CDR3 consisting of the amino acid sequence of SEQ ID NO: 26, and
a light chain variable region that comprises a CDR1 consisting of the amino acid sequence of SEQ ID NO: 30, a CDR2 consisting of the amino acid sequence of SEQ ID NO: 31, and a CDR3 consisting of the amino acid sequence of SEQ ID NO: 32.
12 . A composition comprising the antibody of claim 10 .
13 . A composition comprising the antibody of claim 11 .
14 . A method for neutralizing a bispecific antibody, the method comprising:
providing a blood-derived sample obtained from a test subject who was administered the bispecific antibody, wherein the bispecific antibody comprises a first heavy chain comprising the amino acid sequence of SEQ ID NO: 9, a second heavy chain comprising the amino acid sequence of SEQ ID NO: 11, and two light chains, each comprising the amino acid sequence of SEQ ID NO: 10; and
contacting the blood-derived sample with both:
(a) the antibody of claim 4 , and
(b) an antibody that comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 3 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 4.
15 . A method for neutralizing a bispecific antibody, the method comprising:
providing a blood-derived sample obtained from a test subject who was administered the bispecific antibody, wherein the bispecific antibody comprises a first heavy chain comprising the amino acid sequence of SEQ ID NO: 9, a second heavy chain comprising the amino acid sequence of SEQ ID NO: 11, and two light chains, each comprising the amino acid sequence of SEQ ID NO: 10; and
contacting the blood-derived sample with both:
(a) the composition of claim 12 , and
(b) a composition comprising an antibody that comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 3 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 4.
16 . A method for neutralizing a bispecific antibody, the method comprising:
providing a blood-derived sample obtained from a test subject who was administered the bispecific antibody, wherein the bispecific antibody comprises a first heavy chain comprising the amino acid sequence of SEQ ID NO:9, a second heavy chain comprising the amino acid sequence of SEQ ID NO: 11, and two light chains, each comprising the amino acid sequence of SEQ ID NO: 10; and
contacting the blood-derived sample with both:
(a) the antibody of claim 10 , and
(b) an antibody comprising
a heavy chain variable region that comprises a CDR1 consisting of the amino acid sequence of SEQ ID NO: 24, a CDR2 consisting of the amino acid sequence of SEQ ID NO: 25, and a CDR3 consisting of the amino acid sequence of SEQ ID NO: 26; and
a light chain variable region that comprises a CDR1 consisting of the amino acid sequence of SEQ ID NO: 30, a CDR2 consisting of the amino acid sequence of SEQ ID NO: 31, and a CDR3 consisting of the amino acid sequence of SEQ ID NO: 32.