TGF-beta in human milk is associated with wheeze in infancy.
BACKGROUND
Cytokines secreted in human milk might play important roles in newborn health and in the development of infant immune responses. We investigated the relationship of the concentration and dose of cytokines in human milk to infant wheeze at 1 year of age.


OBJECTIVE
Our objective was to test whether the cytokines in milk could account for some of the apparent protective effect of breast-feeding against wheeze in the first year of life.


METHODS
Data on breast-feeding and infant wheeze were collected prospectively from birth to 1 year from 243 mothers participating in the Infant Immune Study in Tucson, Arizona. Breast milk samples obtained at a mean age of 11 days postpartum were assayed by means of ELISA for concentrations of TGF-beta1, IL-10, TNF-alpha, and the soluble form of CD14. The dose of each cytokine was assessed for a relationship with wheeze in bivariate and logistic regression analyses.


RESULTS
Increasing duration of breast-feeding was significantly associated with a decreased prevalence of wheeze (P =.039). There was wide variability in levels of each cytokine in milk, as well as variability between women in the amount of each cytokine produced. There was a significant inverse association between the dose of TGF-beta1 received through milk with the percentage of wheeze (P =.017), and the relationship was linear (P =.006). None of the other cytokines showed a linear relationship with wheeze. In multivariate analyses the risk of wheeze was significantly decreased (odds ratio, 0.22; 95% CI 0.05-0.89; P =.034) with increasing TGF-beta1 dose (long breast-feeding and medium-high TGF-beta1 level compared with short breast-feeding and low TGF-beta.


CONCLUSIONS
This analysis shows that the dose of TGF-beta1 received from milk has a significant relationship with infant wheeze, which might account for at least some of the protective effect of breast-feeding against wheeze.
Oddy
Wendy H
WH
Department of Nutrition, Dietetics, and Food Science, University of Technology, Perth, Australia.
Halonen
Marilyn
M
Martinez
F D
FD
Lohman
I Carla
IC
Stern
Debra A
DA
Kurzius-Spencer
Margaret
M
Guerra
Stefano
S
Wright
Anne L
AL
D001942:Breast Feeding; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008895:Milk, Human / Q000737:chemistry*; D015999:Multivariate Analysis; D012135:Respiratory Sounds / Q000209:etiology*; D012307:Risk Factors; D013997:Time Factors; D016212:Transforming Growth Factor beta / Q000008:administration & dosage / Q000032:analysis*; D053773:Transforming Growth Factor beta1
C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1