A highly potent extended half-life antibody as a potential RSV vaccine surrogate for all infants.

Prevention of respiratory syncytial virus (RSV) illness in all infants is a major public health priority. However, no vaccine is currently available to protect this vulnerable population. Palivizumab, the only approved agent for RSV prophylaxis, is limited to high-risk infants, and the cost associated with the requirement for dosing throughout the RSV season makes its use impractical for all infants.

Structural insights into the interaction of human IgG1 with FcγRI: no direct role of glycans in binding.

The three-dimensional structure of a human IgG1 Fc fragment bound to wild-type human FcγRI is reported. The structure of the corresponding complex was solved at a resolution of 2.4 Å using molecular replacement; this is the highest resolution achieved for an unmutated FcγRI molecule.

Molecular basis for the antagonistic activity of an anti-CXCR4 antibody.

Antagonistic antibodies targeting the G-protein C-X-C chemokine receptor 4 (CXCR4) hold promising therapeutic potential in various diseases. We report for the first time the detailed mechanism of action at a molecular level of a potent anti-CXCR4 antagonistic antibody (MEDI3185). We characterized the MEDI3185 paratope using alanine scanning on all 6 complementary-determining regions (CDRs).

Structural insights into neonatal Fc receptor-based recycling mechanisms.

We report the three-dimensional structure of human neonatal Fc receptor (FcRn) bound concurrently to its two known ligands. More particularly, we solved the crystal structure of the complex between human FcRn, wild-type human serum albumin (HSA), and a human Fc engineered for improved pharmacokinetics properties (Fc-YTE). The crystal structure of human FcRn bound to wild-type HSA alone is also presented.

Targeting the junction of CɛmX and ɛ-migis for the specific depletion of mIgE-expressing B cells.

Monoclonal antibodies targeting the extracellular region of the human IgE heavy chain membrane-tethering domain have been proposed for treating allergies caused by hyperproliferative monoclonal expansion of IgE-producing B cells. Antibodies against this target are expected to deplete membrane IgE (mIgE) displaying B cells and leave B cells of other immunoglobulin isotypes intact. Because of alternative splicing, the mIgE heavy chain has two isoforms that differ in their membrane-proximal segment.

Crystallization and preliminary X-ray diffraction analysis of the complex of a human anti-ephrin type-A receptor 2 antibody fragment and its cognate antigen.

The recombinant N-terminal domain of human ephrin type-A receptor 2 (rEphA2) has been crystallized in complex with the recombinantly produced Fab fragment of a fully human antibody (1C1; IgG1/kappa). These are the first reported crystals of an ephrin receptor bound to an antibody. The orthorhombic crystals belonged to space group C222(1) (the 00l reflections obey the l = 2n rule), with unit-cell parameters a = 78.

Structural characterization of a human Fc fragment engineered for extended serum half-life.

The first three-dimensional structure of a human Fc fragment genetically engineered for improved pharmacokinetics properties is reported. When introduced into the C(H)2 domain of human immunoglobulin G (IgG) molecules, the triple mutation M252Y/S254T/T256E ('YTE') causes an about 10-fold increase in their binding to the human neonatal Fc receptor (FcRn). This translates into an almost 4-fold increase in the serum half-life of YTE-containing human IgGs in cynomolgus monkeys.

Crystallization and preliminary X-ray diffraction analysis of the complex between a human anti-interferon antibody fragment and human interferon alpha-2A.

Recombinant human interferon alpha-2A (rhIFN-alpha-2A) has been crystallized in complex with the recombinantly produced Fab fragment of a therapeutic monoclonal antibody (MEDI545; IgG1/kappa) which targets several human interferon alpha subtypes. This constitutes the first reported crystals of a human type I interferon bound to an antibody. The orthorhombic crystals belonged to either space group I222 or I2(1)2(1)2(1), with unit-cell parameters a = 134.

Modulation of the effector functions of a human IgG1 through engineering of its hinge region.

We report here the engineering of a humanized anti-human EphA2 mAb (mAb 12G3H11) in an effort to explore the relationship between the hinge of a human IgG1 and its effector functions. mAb 12G3H11, used here as a model, is directed against the human receptor tyrosine kinase EphA2, which is an actively investigated target for cancer therapy due to its up-regulation in many cancer cells. Various rational modifications were introduced into the hinge region of mAb 12G3H11.