Low endotoxin content is critical for protein reagents. This is because interaction of endotoxin with TLR/CD14/MD2 complexes and TRP channels can trigger an abundant variety of cellular responses which can lead to experimental results difficult to be interpreted.
the classical IgG Fc receptors serve as bridges connecting humoral responses and cell-medicated immune responses. The MHC-class I like FcRn binds to antibodies and protects the latter from being degraded through their endocytic journal. As such FcRn can safely recycle the antibodies and lead to the long systemic half life of the latter.
