The structural basis of chicken, swine and bovine CD8αα dimers provides insight into the co-evolution with MHC I in endotherm species.It is unclear how the pivotal molecules of the adaptive immune system (AIS) maintain their inherent characteristics and relationships with their co-receptors over the course of co-evolution.  Our data propose that a few key conserved residues are able to ensure the CD8α own structural characteristics despite the great sequence variation that occurs during evolution in endotherms.
THERM