Making the IgG1 core hinge more IgG4-like by replacing the proline with serine did not permit half-molecule exchange, but IgG1 containing both the serine and the complete IgG4 third constant heavy ...

1,2 Previous mapping of IgG1–4 Fc region sequences has revealed their relative similarities, with IgG1 and IgG2 being the most alike, while IgG3 and IgG4 show the greatest differences ...