Structural Biology

Complement Receptor Complex Structure

Science Signaling  03 May 2011:
Vol. 4, Issue 171, pp. ec126
DOI: 10.1126/scisignal.4171ec126

Complement receptor 2 (CR2), found in B cells and follicular dendritic cells, binds to a ligand, C3d, which is bound to antigen. The antigen simultaneously binds to the B cell antigen recognition complex such that this coligation enhances the antibody response. A previously published crystal structure of the CR2:C3d complex possibly represented a nonphysiological interaction. Hence, van den Elsen and Isenman report a structure in which the molecular details of the interface are more consistent with biochemical data, supporting physiological relevance and providing a foundation for rational design of therapeutics against autoreactive B cells.

J. M. H. van den Elsen, D. E. Isenman, A crystal structure of the complex between human complement receptor 2 and its ligand C3d. Science 332, 608–611 (2011). [Abstract] [Full Text]