Influence of Breast-feeding on the Production of Cytokines

Authors

  • YUKI SHIMAOKA,

  • YOH HIDAKA,

  • HISATO TADA,

  • KEIKO TAKEOKA,

  • NOBUYUKI AMINO,

  • YASUHIKO MORIMOTO


Address reprint requests to Dr. Yoh Hidaka, Department of Laboratory Medicine, Osaka University Graduate School of Medicine, D2, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.

Abstract

PROBLEM: Recently, we reported increases in the production of interferon-γ (IFN-γ), interleukin-2 (IL-2), and IL-4 during the postpartum period. The present study was undertaken to investigate whether these increases might be explained by increased prolactin while breast-feeding.
METHOD: Whole blood from 41 women who were breast-feeding, 13 women not breast-feeding, and 31 healthy non-pregnant women was stimulated with phorbol 12-myristate 13-acetate and ionomycin, and the levels of cytokines in the supernatant were measured by enzyme-linked immunosorbent assay. Their serum levels of prolactin were measured by enzyme immunoassay.
RESULTS: Increases in IFN-γ, IL-2, IL-4, and IL-10 production were observed in women who were breast-feeding but not in women who were not breast-feeding. Serum levels of prolactin correlated with the levels of IFN-γ in culture supernatant.
CONCLUSIONS: These results suggest that breast-feeding induces production of cytokines and that IFN-γ production is enhanced by physiological concentrations of prolactin.

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