X-ray crystal structure of C3d: a C3 fragment and ligand for complement receptor 2.
Nagar, B., Jones, R.G., Diefenbach, R.J., Isenman, D.E., Rini, J.M.(1998) Science 280: 1277-1281
- PubMed: 9596584 
- DOI: 10.1126/science.280.5367.1277
- Primary Citation of Related Structures:  
1C3D - PubMed Abstract: 
Activation and covalent attachment of complement component C3 to pathogens is the key step in complement-mediated host defense. Additionally, the antigen-bound C3d fragment interacts with complement receptor 2 (CR2; also known as CD21) on B cells and the ...