IL-21 binding proteins
The present disclosure provides proteins comprising antigen binding sites of antibodies that bind to interleukin-21 (IL-21) and uses thereof, e.g., in therapy.
1. An IL-21-binding protein comprising an antigen binding domain of an antibody, wherein the antigen binding domain binds to IL-21, wherein the antigen binding domain comprises:
(i) a V H comprising a complementarity determining region (CDR) 1 comprising the sequence set forth in SEQ ID NO: 5, a CDR2 comprising the sequence set in SEQ ID NO: 6 and a CDR3 comprising the sequence set forth in SEQ ID NO: 7; and
(ii) a V L comprising a CDR1 comprising the sequence set forth in SEQ ID NO: 8, a CDR2 comprising the sequence set forth in SEQ ID NO: 9 and a CDR3 comprising the sequence set forth in SEQ ID NO: 10.
2. The IL-21-binding protein of claim 1 , wherein the antigen binding domain comprises a V H comprising a sequence at least 95% identical to the sequence set forth in SEQ ID NO: 2.
3. The IL-21-binding protein of claim 1 , wherein the antigen binding domain comprises a V L comprising a sequence at least 95% identical to the sequence set forth in SEQ ID NO: 3.
4. The IL-21-binding protein of claim 1 , wherein the antigen binding domain comprises a V H comprising the sequence set forth in SEQ ID NO: 2.
5. The IL-21-binding protein of claim 1 , wherein the antigen binding domain comprises a V L comprising the sequence set forth in SEQ ID NO: 3.
6. The IL-21-binding protein of claim 1 , wherein the antigen binding domain comprises a V H comprising the sequence set forth in SEQ ID NO: 2 and a V L comprising the sequence set forth in SEQ ID NO: 3.
7. The IL-21-binding protein of claim 1 wherein the antigen binding domain comprises at least a heavy chain variable region (V H ) and a light chain variable region (V L ), wherein the V H and V L bind to form a Fv comprising an antigen binding domain, wherein the V H and the V L are in a single polypeptide chain or the V L and V H are in separate polypeptide chains.
8. The IL-21-binding protein of claim 7 , wherein if the V H and V L are in a single polypeptide chain, the protein is:
(i) a single chain Fv fragment (scFv);
(ii) a dimeric scFv (di-scFv);
(iii) one of (i) or (ii) linked to a constant region of an antibody, Fc or a heavy chain constant domain (C H ) 2 and/or C H 3; or
if the V H and V L are in separate polypeptide chains the protein is:
(i) a diabody;
(ii) a triabody;
(iii) a tetrabody;
(iv) a Fab;
(v) a F(ab′) 2 ;
(vi) a Fv;
(vii) one of (i) to (vi) linked to a constant region of an antibody, Fc or a heavy chain constant domain (C H ) 2 and/or C H 3; or
(viii) an antibody.
9. The IL-21 binding protein of claim 1 which is not conjugated to another compound.
10. A composition comprising the IL-21-binding protein of claim 1 and a pharmaceutically acceptable carrier.