1T04

Three dimensional structure of a humanized anti-IFN-Gamma Fab in C2 space group

Summary for 1T04

• Entry DOI: 10.2210/pdb1t04/pdb
• Related: 1B2W 1B4J
• Descriptor: Huzaf Antibody Light Chain, Huzaf Antibody Heavy Chain (3 entities in total)
• Functional Keywords: antibody engineering, humanized and chimeric antibody, fab, three-dimensional structure, gamma-interferon, immune system
• Biological source: Homo sapiens (human); More
• Total number of polymer chains: 4
• Total formula weight: 93616.07

Authors

Bourne, P.C.,Terzyan, S.S.,Cloud, G.,Landolfi, N.F.,Vasquez, M.,Edmundson, A.B. (deposition date: 2004-04-07, release date: 2004-10-05, Last modification date: 2024-10-09)

Primary citation

Bourne, P.C.,Terzyan, S.S.,Cloud, G.,Landolfi, N.F.,Vasquez, M.,Edmundson, A.B.
Three-dimensional structures of a humanized anti-IFN-gamma Fab (HuZAF) in two crystal forms.
Acta Crystallogr.,Sect.D, 60:1761-1769, 2004

PubMed Abstract: Three-dimensional structures were determined for two crystal forms (orthorhombic P2(1)2(1)2(1) and monoclinic C2) of the Fab from the humanized version of a murine monoclonal antibody (AF2) that possesses binding and potent neutralizing activity against human interferon gamma (IFN-gamma). This humanized antibody (HuZAF; USAN name fontolizumab) is currently in phase II clinical trials for the treatment of Crohn's disease. HuZAF exhibits binding and IFN-gamma neutralizing capacities that closely approximate those of the original antibody. It is shown that HuZAF, whose VH domain was designed using a best-sequence-fit approach, is closer structurally to its mouse precursor than is a version whose VH was constructed using a human sequence with lower homology to the original mouse sequence. This work thus offers direct structural evidence in support of the best-sequence-fit approach and adds to previous results of biological and biochemical evaluations of distinctly engineered antibodies that also favored the use of a best-sequence-fit strategy. A second crystal type appeared during attempts to crystallize the Fab-IFN-gamma complex. The antibody-antigen complex that existed in solution dissociated in the crystallization mixture. A conformationally altered but unliganded HuZAF protein crystallized in a different space group (C2), with two Fab molecules in the asymmetric unit. In this crystal lattice, no space was available for accommodating the IFN-gamma antigen. Thus, there are currently three slightly different structures of the HuZAF Fab.

PubMed: 15388922
DOI: 10.1107/S0907444904018670

Experimental method

X-RAY DIFFRACTION (3 Å)