Comparison of IgE and IgG1 Structure heavy chain domains 5 vs.4 mol.wt.188,000Vs.146,000 carbohydrate 12%Vs.2-3% half-life (serum)2 1/2 vs.21dComparison of IgE and IgG1 Structure IgE IgG1 ◼ heavy chain domains 5 vs. 4 ◼ mol. wt. 188,000 vs. 146,000 ◼ carbohydrate 12% vs. 2-3% ◼ half-life (serum) 2 1/2 vs. 21d