Immunoglobulin
- IgG
eIgG class functions:
Uable to bind
complement (except IgG4)
Uthe only Ig
that can cross placental barrier
Uacts as a
defense mechanism for fetuses and newborns
Uinfant=s begin producing own IgG at 6 months
Uadult levels
of IgG reached at age 6 years
Udecreased
levels result in recurrent infections
Uincreased IgG
seen in autoimmune diseases
Ubind to Fc
receptors of macrophages (opsonization)
Uonly Ig with
antitoxin activity (destroys toxins)
UIg produced
in secondary immune response
monomeric IgG
