We demonstrated significantly higher EFABP concentrations in breast milk of mothers who delivered boys, but when we corrected for body weight regardless of sex we found that the positive correlation between EFABP concentrations and the body weight of newborns was not related to sex but to higher body weight in boys.
Birth weight correlated positively with EFABP concentrations in breast milk.
We found a positive correlation between AFABP and EFABP rather than a compensatory regulation as reported in adipose tissue (36), indicating an important role for EFABP.
We found no relationship between adiponectin, AFABP, EFABP, or leptin and age, body height of mothers, or ponderal index of newborns.
We demonstrated, for the first time, the presence of adiponectin, AFABP, and EFABP in human breast milk.
Moreover, there were similar appreciable Correlations found, as mentioned above (AFABP vs EFABP, r = 0.471, P = 0.0002; EFABP vs birth weight, r = 0.289, P = 0.029; and leptin vs body weight before pregnancy, r = 0.418, P = 0.003; at the time of delivery, r = 0.410, P = 0.003; BMI before pregnancy, r = 0.513, P = 0.0001; and at the time of delivery, r = 0.487, P = 0.0003).
The specificity of the immunoassay was confirmed by reactivity with recombinant EFABP (Abnova).
The protein content was determined by the Bradford method (Sigma-Aldrich) with recombinant EFABP (Biovendor) with >95% purity confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (data not shown) as a calibrator, prepared at concentrations of 40, 20, 10, 5, 2, and 1 [micro]g/L in 5% BSA (w/v) in TBS-Tw and 100 [micro]L directly pippeted into the wells.
Skim breast milk samples from 2 participants with baseline EFABP concentrations of 5.8 and 12.4 [micro]g/L were enriched with increasing amounts of recombinant EFABP (+2.0, +4.0 and +10.0 [micro]g/L) and assayed.
There was no relationship with the number of previous pregnancies or deliveries or any other variable in mothers or newborns, nor with AFABP, EFABP, or leptin milk concentrations.
We found a strong positive correlation between AFABP and EFABP (r = 0.593, P <0.0001) (Fig.
With a sandwich ELISA method recently developed by Biovendor Laboratory Medicine, Inc., we found that the assay is highly specific for human A-FABP, with no detectable cross-reactivity with other types of FABPs [heart-type FABP (H-FABP), liver-type FABP (L-FABP), or keratinocyte FABP (EFABP
)], leptin, adiponectin, resistin, tumor necrosis factor-[alpha], C-reactive protein, or interleukin-6.