Use of antibodies for detection of IL-10

A method of detecting the level of soluble IL-10 homodimer in a sample, comprising:

• (a) contacting a sample with an antibody or fragment thereof;
• and (b) determining the amount of IL-10 present in the sample by determining the amount of antibody or fragment thereof bound to IL-10;
• wherein the antibody or fragment thereof is a humanized antibody or fragment thereof that binds to IL-10 in homodimeric form by binding a discontinuous epitope comprising residues of both monomers, and wherein said antibody or fragment thereof comprises a variable light chain comprising the amino acid sequences of CDR1, CDR2 and CDR3 of SEQ ID NO:
• 2, and a variable heavy chain comprising the amino acid sequences of CDR1, CDR2 and CDR3 of SEQ ID NO:
• 3, wherein the variable heavy chain further comprises the residues Asn73 and Ser74 of SEQ ID NO:70 which contact IL-10 when said antibody binds to IL-10.