Antibody binding geometry and affinity control inhibitory FcγRIIB receptor signaling

Hayden Fisher.

SASDUF7 – Deglycosylated Fc gamma receptor IIb (CD32b) extracellular domain in complex with human IgG1 6G08 F(ab')

Low affinity immunoglobulin gamma Fc region receptor II-b
Human IgG1 F(ab') 6G08
MWexperimental 62 kDa
MWexpected 45 kDa
VPorod 96 nm3
log I(s) 6.22×101 6.22×100 6.22×10-1 6.22×10-2
Low affinity immunoglobulin gamma Fc region receptor II-b Human IgG1 F(ab') 6G08 small angle scattering data  s, nm-1
ln I(s)
Low affinity immunoglobulin gamma Fc region receptor II-b Human IgG1 F(ab') 6G08 Guinier plot ln 6.23×101 Rg: 3.3 nm 0 (3.3 nm)-2 s2
(sRg)2I(s)/I(0)
Low affinity immunoglobulin gamma Fc region receptor II-b Human IgG1 F(ab') 6G08 Kratky plot 1.104 0 3 sRg
Dmax: 12 nm

Data validation


Fits and models


log I(s)
 s, nm-1
Low affinity immunoglobulin gamma Fc region receptor II-b Human IgG1 F(ab') 6G08 MOLECULAR DYNAMICS FRAME model

Synchrotron SAXS data from solutions of deglycosylated Fc gamma receptor IIb (CD32b) extracellular domain in complex with human IgG1 6G08 F(ab') in 50 mM HEPES, 150 mM KCl, pH 7.5 were collected on the BM29 beam line at the ESRF (Grenoble, France) using a Pilatus 1M detector at a sample-detector distance of 2.9 m and at a wavelength of λ = 0.099 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). Solute concentrations ranging between 1.3 and 5 mg/ml were measured at 20°C. 10 successive 2 second frames were collected. The data were normalized to the intensity of the transmitted beam and radially averaged; the scattering of the solvent-blank was subtracted. The low angle data collected at lower concentration were merged with the highest concentration high angle data to yield the final composite scattering curve.

Low affinity immunoglobulin gamma Fc region receptor II-b (CD32b)
Mol. type   Protein
Organism   Homo sapiens
Olig. state   Monomer
Mon. MW   20.4 kDa
 
UniProt   P31994 (43-217)
Sequence   FASTA
 
Human IgG1 F(ab') 6G08
Mol. type   Protein
Organism   Homo sapiens
Olig. state   Monomer
Mon. MW   24.2 kDa
Sequence   FASTA