The immunologically privileged site that protects the fetus from mother's immune system is most likely due to the fact that _____.
A)mother's IgG do not cross the placenta
B)fetal portion of placenta does not exhibit MHC molecules
C)alpha-fetoprotein inhibits immune responses
D)two of the above

Question

Quizplus · Accepted Answer

Both B and C are correct. The fetal portion of the placenta does not exhibit MHC molecules that are required for initiation of immune responses, therefore the mother's immune system does not recognize the fetus as a foreign body. Secondly, alpha-fetoprotein, which is produced by the fetus, can inhibit immune responses and contributes towards the immunologically privileged site. Additionally, maternal IgG does cross the placenta, but the presence of MHC molecules on the placenta is more significant in providing protection to the fetus from maternal immune system.

The Immunologically Privileged Site That Protects the Fetus from Mother's