Table 2.
Protein content of human breast milk from the different lactation stages (see also Figure S1).
| Proteins | 5–11 Days | 12–30 Days | 1–2 Months | 2–4 Months | 4–8 Months |
|---|---|---|---|---|---|
| (n = 90) | (n = 90) | (n = 90) | (n = 90) | (n = 90) | |
| Major breast milk proteins | |||||
| α-lactalbumin (g/L), Median (IQR) | 3.27 (0.60) | 3.16 (0.55) | 2.84 a (0.55) | 2.53 a (0.47) | 2.28 a (0.63) |
| Lactoferrin (g/L), Median (IQR) | 3.30 (2.11) | 1.86 a (0.89) | 1.24 a (0.53) | 1.15 (0.46) | 1.17 (0.47) |
| Serum albumin (g/L), Median (IQR) | 0.48 (0.14) | 0.48 (0.14) | 0.42 (0.09) | 0.44 (0.10) | 0.42 (0.08) |
| Total caseins (g/L), Median (IQR) | 5.84 (3.17) | 6.57 a (2.15) | 6.24 (2.25) | 5.79 a (1.69) | 5.60 (1.73) |
| Immune factors | |||||
| IgA (mg/L), Median (IQR) | 1148 (1022) | 615 a (494) | 553 a (232) | 557 (312) | 564 (337) |
| IgM (mg/L), Median (IQR) | 117 (168) | 47 a (47) | 35 a (31) | 35 (29) | 25 a (25) |
| IgG (mg/L), Median (IQR) | 22 (13) | 23 (12) | 20 (14) | 24 (15) | 23 (14) |
| TGF-β1 (ng/L), Median (IQR) | 1258 (1305) | 685 a (482) | 600 (356) | 598 (379) | 659 (410) |
| TGF-β2 (ng/L), Median (IQR) | 5286 (10,444) | 2322 a (3100) | 1877 a (1890) | 1920 a (2112) | 2311 b (2868) |
a p < 0.05 vs. previous stage; b p < 0.05 vs. previous 1–2 months stage.