Il-21 antibodies

Abstract

The invention relates to IL-21, to antibodies and related fragments thereof for binding to IL-21, to production of said antibodies and fragments and to use of said antibodies and fragments for detection and therapy of various conditions, in particular inflammation, infection and oncology.

1 . An antigen binding site that binds to or specifically binds to IL-21 and enhances IL-21 activity, wherein the antigen binding site comprises:
 (a) a framework region (FR) 1 comprising a sequence at least about 65% identical to a sequence set forth in SEQ ID NO: 24, a FR2 comprising a sequence at least about 80% identical to a sequence set forth in SEQ ID NO: 25, a FR3 comprising a sequence at least about 75% identical to a sequence set forth in SEQ ID NO: 26, and a FR4 comprising a sequence at least about 80% identical to a sequence set forth in SEQ ID NO: 27;   (b) a FR1 comprising a sequence at least about 80% identical to a sequence set forth in SEQ ID NO: 28, a FR2 comprising a sequence at least about 80% identical to a sequence set forth in SEQ ID NO: 29, a FR3 comprising a sequence at least about 80% identical to a sequence set forth in SEQ ID NO: 30, and a FR4 comprising a sequence at least about 80% identical to a sequence set forth in SEQ ID NO: 31;   (c) a FR1 comprising a sequence at least about 65% identical to a sequence set forth in SEQ ID NO: 32, a FR2 comprising a sequence at least about 80% identical to a sequence set forth in SEQ ID NO: 33, a FR3 comprising a sequence at least about 75% identical to a sequence set forth in SEQ ID NO: 34, and a FR4 comprising a sequence at least about 80% identical to a sequence set forth in SEQ ID NO: 35; or   (d) a FR1 comprising a sequence at least about 80% identical to a sequence set forth in SEQ ID NO: 36, a FR2 comprising a sequence at least about 80% identical to a sequence set forth in SEQ ID NO: 37, a FR3 comprising a sequence at least about 80% identical to a sequence set forth in SEQ ID NO: 38, and a FR4 comprising sequence at least about 80% identical to a sequence set forth in SEQ ID NO: 39.