Format

Send to

Choose Destination
See comment in PubMed Commons below
J Biol Chem. 2014 Aug 22;289(34):23596-608. doi: 10.1074/jbc.M114.569061. Epub 2014 Jun 26.

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

Author information

1
From the Dyax Corp., Burlington, Massachusetts 01803.
2
Beryllium, Bainbridge Island, Washington 98110, and.
3
Biokin, Watertown, Massachusetts 02472.
4
From the Dyax Corp., Burlington, Massachusetts 01803, dsexton@dyax.com.

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.

KEYWORDS:

Antibody Engineering; Enzyme Inhibitor; Inflammation; Kallikrein; Protease

PMID:
24970892
PMCID:
PMC4156074
DOI:
10.1074/jbc.M114.569061
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Support Center