Immunoglobulins Immunology Review 383
Form
Molecular
weight
(daltons)
Heavy chain
Light chain
% of total Ig
Serum
concentration
(mg/dL)
Antigen-
binding
sites
Complement
fixation
IgGMonomer150,000Gamma (g)Kappa (k) or
lambda (l)70–75800–1,6002
YesIgMPentamer900,000Mu (m)kor l10
120–150
10
YesIgAMonomer & dimer160,000 or 400,000Alpha (a)kor l10–15
70–350
2 or 4NoIgDMonomer180,000Delta (d)kor l<1
1–3
2
NoIgEMonomer190,000Epsilon (e)kor l0.002
0.005
2
Nocontinued...