Abstract:

Objective: Casein glycomacropeptide (CGMP) is a kind of peptide containing 64 amino acid residues, which has
many physiological functions and unique nutritional properties. This study aimed to explore its effects on peripheral blood
lymphocyte subsets in mice. Methods: After being by gavage given different doses of CGMP (30, 60, and 120 μg/d), healthy
mice were tested for the changes of the peripheral blood lymphocyte by flow cytometry. Results: In the short-term gavage
experiment, CGMP resulted in a significant decrease in the proportion of CD3+, and after 12 h, it recovered to the level
before oral administration; CGMP at 30 and 120 μg/d resulted in a significant decrease in the proportions of CD3+CD4+
lymphocytes and CD3+CD8+ lymphocytes in peripheral blood after 4 h, while CGMP at 60 μg/d resulted in no significant
change. In the long-term gavage experiment, CGMP resulted in a significant increase in CD3+ lymphocytes and CD3+CD4+
lymphocytes in peripheral blood at days 2 and 4 (P ＜ 0.05). Compared with the control group, CGMP at 120 μg/d resulted
in a significant increase in CD3+CD8+ lymphocytes in peripheral blood (P ＜ 0.05), but at 30 μg/d caused no significant
increase (P ＞ 0.05). Moreover, at day 2, CGMP at the two dosages resulted in a significant increase in CD3+CD4+/
CD3+CD8+ in peripheral blood (P ＜ 0.05). Conclusion: CGMP can cause peripheral blood lymphocyte subsets to change
in mice, and regulate the balance of T lymphocyte subsets in peripheral blood. Therefore, CGMP can be used as a functional
food to relieve the imbalance of T lymphocyte in peripheral blood.

Key words: casein glycomacropeptide (CGMP), lymphocyte subsets, CD4+ cells, CD8+ cells, functional food