Assay method for relaxin

An assay method for relaxin, wherein the method comprises

• (a) binding relaxin with a capture antibody comprising
• a VH domain having an amino acid sequence set forth in SEQ ID NO:
• 21, and a VL domain having an amino acid sequence set forth in SEQ ID NO:
• 22;
• or a functional fragment thereof which has independently at least 80% sequence identity, or at least 85%, 90%, 95%, 96%, 97%, 98% or 99% sequence identity to any one of SEQ ID NO:
• 21 or 22, wherein the functional fragment is capable of binding relaxin, in particular canine or feline relaxin, preferably canine relaxin;
• and
• (b) binding relaxin with a first detection antibody comprising
• a VH domain having an amino acid sequence set forth in SEQ ID NO:
• 19, and a VL domain having an amino acid sequence set forth in SEQ ID NO:
• 20;
• or a functional fragment thereof which has independently at least 80% sequence identity, or at least 85%, 90%, 95%, 96%, 97%, 98% or 99% sequence identity to any one of SEQ ID NO:
• 19 or 20, wherein the functional fragment is capable of binding relaxin, in particular canine or feline relaxin, preferably canine relaxin;
• and
• (c) binding relaxin with a second detection antibody comprising
• a VH domain having an amino acid sequence set forth in SEQ ID NO:
• 23, and a VL domain having an amino acid sequence set forth in SEQ ID NO:
• 24;
• or a functional fragment thereof which has independently at least 80% sequence identity, or at least 85%, 90%, 95%, 96%, 97%, 98% or 99% sequence identity to any one of SEQ ID NO:
• 23 or 24, wherein the functional fragment is capable of binding relaxin, in particular canine or feline relaxin, preferably canine relaxin.

An anti-relaxin antibody or functional fragment thereof, wherein said antibody or functional fragment comprises

• (i) a VL domain comprising a CDR1 region having an amino acid sequence set forth in SEQ ID NO:
• 10, a CDR2 region having an amino acid sequence set forth in SEQ ID NO:
• 11, and a CDR3 region having an amino acid sequence set forth in SEQ ID NO:
• 12, and a VH domain comprising a CDR1 region having an amino acid sequence set forth in SEQ ID NO:
• 7, a CDR2 region having an amino acid sequence set forth in SEQ ID NO:
• 8, and a CDR3 region having an amino acid sequence set forth in SEQ ID NO:
• 9;
• or a functional fragment thereof which has independently at least 80% sequence identity, or at least 85%, 90%, 95%, 96%, 97%, 98% or 99% sequence identity to any one of SEQ ID NO:
• 7-12, wherein the functional fragment is capable of binding relaxin, in particular canine or feline relaxin, preferably canine relaxin;
• or
• (ii) a VL domain comprising a CDR1 region having an amino acid sequence set forth in SEQ ID NO:
• 4, a CDR2 region having an amino acid sequence set forth in SEQ ID NO:
• 5, and a CDR3 region having an amino acid sequence set forth in SEQ ID NO:
• 6, and a VH domain comprising a CDR1 region having an amino acid sequence set forth in SEQ ID NO:
• 1, a CDR2 region having an amino acid sequence set forth in SEQ ID NO:
• 2, and a CDR3 region having an amino acid sequence set forth in SEQ ID NO:
• 3;
• or a functional fragment thereof which has independently at least 80% sequence identity, or at least 85%, 90%, 95%, 96%, 97%, 98% or 99% sequence identity to any one of SEQ ID NO:
• 1-6, wherein the functional fragment is capable of binding relaxin, in particular canine or feline relaxin, preferably canine relaxin;
• or
• (iii) a VL domain comprising a CDR1 region having an amino acid sequence set forth in SEQ ID NO:
• 16, a CDR2 region having an amino acid sequence set forth in SEQ ID NO:
• 17, and a CDR3 region having an amino acid sequence set forth in SEQ ID NO:
• 18, and a VH domain comprising a CDR1 region having an amino acid sequence set forth in SEQ ID NO:
• 13, a CDR2 region having an amino acid sequence set forth in SEQ ID NO:
• 14, and a CDR3 region having an amino acid sequence set forth in SEQ ID NO:
• 15;
• or a functional fragment thereof which has independently at least 80% sequence identity, or at least 85%, 90%, 95%, 96%, 97%, 98% or 99% sequence identity to any one of SEQ ID NO:
• 13-18, wherein the functional fragment is capable of binding relaxin, in particular canine or feline relaxin, preferably canine relaxin.

An anti-relaxin antibody or functional fragment thereof, wherein said antibody or functional fragment comprises

• (i) a VH domain having an amino acid sequence set forth in SEQ ID NO:
• 19, and a VL domain having an amino acid sequence set forth in SEQ ID NO:
• 20, or
• (ii) a VH domain having an amino acid sequence set forth in SEQ ID NO:
• 21, and a VL domain having an amino acid sequence set forth in SEQ ID NO:
• 22, or
• (iii) a VH domain having an amino acid sequence set forth in SEQ ID NO:
• 23, and a VL domain having an amino acid sequence set forth in SEQ ID NO:
• 24;
• and wherein the functional fragment thereof has independently at least 80% sequence identity, or at least 85%, 90%, 95%, 96%, 97%, 98% or 99% sequence identity to any one of SEQ ID NO:
• 19, 20, 21, 22, 23, or 24, and wherein the functional fragment thereof is capable of binding relaxin, in particular canine or feline relaxin, preferably canine relaxin.