PDBsum entry 4pub

Immune system

PDB id: 4pub

Contents

Protein chains

212 a.a.

212 a.a.

Metals

_CL

Waters ×479

PDB id:

4pub

Name:

Immune system

Title:

Crystal structure of fab dx-2930

Structure:

Dx-2930 heavy chain. Chain: h. Engineered: yes. Dx-2930 light chain. Chain: l. Engineered: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Expressed in: escherichia coli. Expression_system_taxid: 562. Expression_system_taxid: 562

Resolution:

1.75Å R-factor: 0.174 R-free: 0.214

Authors:

J.Abendroth,T.E.Edwards,A.Nixon,R.Ladner

Key ref:

J.A.Kenniston et al. (2014). Inhibition of plasma kallikrein by a highly specific active site blocking antibody. J Biol Chem, 289, 23596-23608. PubMed id: 24970892 DOI: 10.1074/jbc.M114.569061

Date:

12-Mar-14 Release date: 09-Jul-14

Protein chain

S6C4R2  (S6C4R2_HUMAN) -  IgG H chain from Homo sapiens

Seq: 275 a.a.

Struc: 212 a.a.*

Protein chain

Q7Z3Y4  (Q7Z3Y4_HUMAN) -  Ig-like domain-containing protein from Homo sapiens

Seq: 236 a.a.

Struc: 212 a.a.*

* PDB and UniProt seqs differ at 36 residue positions (black crosses)

DOI no: 10.1074/jbc.M114.569061

J Biol Chem 289:23596-23608 (2014)

PubMed id: 24970892

Inhibition of plasma kallikrein by a highly specific active site blocking antibody.

J.A.Kenniston, R.R.Faucette, D.Martik, S.R.Comeau, A.P.Lindberg, K.J.Kopacz, G.P.Conley, J.Chen, M.Viswanathan, N.Kastrapeli, J.Cosic, S.Mason, M.DiLeo, J.Abendroth, P.Kuzmic, R.C.Ladner, T.E.Edwards, C.TenHoor, B.A.Adelman, A.E.Nixon, D.J.Sexton.

ABSTRACT

Plasma kallikrein (pKal) proteolytically cleaves high molecular weight kininogen to generate the potent vasodilator and the pro-inflammatory peptide, bradykinin. pKal activity is tightly regulated in healthy individuals by the serpin C1-inhibitor, but individuals with hereditary angioedema (HAE) are deficient in C1-inhibitor and consequently exhibit excessive bradykinin generation that in turn causes debilitating and potentially fatal swelling attacks. To develop a potential therapeutic agent for HAE and other pKal-mediated disorders, we used phage display to discover a fully human IgG1 monoclonal antibody (DX-2930) against pKal. In vitro experiments demonstrated that DX-2930 potently inhibits active pKal (Ki = 0.120 ± 0.005 nm) but does not target either the zymogen (prekallikrein) or any other serine protease tested. These findings are supported by a 2.1-Å resolution crystal structure of pKal complexed to a DX-2930 Fab construct, which establishes that the pKal active site is fully occluded by the antibody. DX-2930 injected subcutaneously into cynomolgus monkeys exhibited a long half-life (t½ ∼12.5 days) and blocked high molecular weight kininogen proteolysis in activated plasma in a dose- and time-dependent manner. Furthermore, subcutaneous DX-2930 reduced carrageenan-induced paw edema in rats. A potent and long acting inhibitor of pKal activity could be an effective treatment option for pKal-mediated diseases, such as HAE.