BACKGROUND
Maternal allergy and gestational exposures can alter the concentration of type-1/type-2/T-regulatory markers in breast milk. We tested whether maternal risk factors are related to breast milk immune markers.
METHODS
Expecting mothers were enrolled in 2008-2010 in South Carolina in prenatal clinics and classes. Interferon (IFN)-γ-induced protein 10 (CXCL10), CCL11, interleukin (IL)-1β, IL-4, IL-5, IL-6, CXCL8, IL-10, IL-12(p70), IL-13, transforming growth factor (TGF)-β1, and immunoglobulin (Ig)A in 115 whey samples were measured by immunoassays. Maternal asthma, eczema, rhinitis, smoking, urogenital infections during gestation, pet exposure, education, race/ethnicity, age, body mass, and the child's birth date and sex were ascertained. The effects of these risk factors on immune markers were estimated using general linear models.
RESULTS
Maternal asthma was linked to higher levels of IL-5, rhinitis to lower levels of IL-5 and INF-γ, and eczema to lower levels of IL-6. Gestational smoking was related to increased concentrations of CXCL8 and IL-6. African-American mothers had markedly higher levels of IL-6, IFN-γ, and CXCL8. Urogenital infections, maternal age, body mass, child's sex, and season of birth contributed to the variation.
CONCLUSIONS
The impact of maternal allergies on immune markers in breast milk was small compared with that of maternal nondisease characteristics.