Figure 1.

Effects of a diet containing free amino acids (AA diet) on immunoglobulin production. (A) C57BL/6 mice at 7–8 weeks of age were fed either experimental diet (AA diet) or control diet [casein-containing diet (CAS) diet)]. Administration of diets was maintained for 5 weeks. Levels of total serum immunoglobulins (B) and SIgA in the colon (C) were measured at the end of 7, 21, and 35 days of diet consumption by enzyme-linked immunosorbent assay (ELISA) (n = 5). Statistical analysis was performed between CAS-fed and AA-fed group at the end of each experimental time point using Student’s t test for parametric data. p < 0.05.