IMPACT OF MATERNAL COELIAC DISEASE AND GLUTEN EXPOSURE ON LACTOFERRIN AND SECRETORY IGA IN HUMAN MILK

Background: Among its principal bioactive components, human milk (HM) contains lactoferrin (LF) and secretory immunoglobulin A (sIgA), which act as major effectors of innate and adaptive immunity. Their concentrations depend on maternal health and diet, yet the influence of coeliac disease (CD) and adherence to the gluten-free diet on milk immunity remains unclear. This study evaluated the impact of maternal CD on LF and sIgA levels in HM and examined their association with recent gluten exposure assessed through detection of gluten immunogenic peptides (GIP). Methods: : HM samples from 41 lactating mothers (21 with CD; 20 non-CD) were analysed. LF and sIgA concentrations were quantified by ELISA, and GIP was detected by lateral flow immunoassay. Group differences were examined with non-parametric tests and statistical models. Results: : LF concentrations were significantly higher in CD mothers compared with controls (p = 0.023) and remained elevated after adjusting for lactation stage. sIgA showed no overall differences between groups but displayed a lactation-stage-dependent pattern in CD mothers, with progressive increases during later lactation (p = 0.004). LF and sIgA correlated only in the CD group (r = 0.44; p = 0.046). In CD mothers, both markers tended to be higher in GIP-positive samples, suggesting immune activation after gluten exposure. Conclusions: : Maternal CD is associated with increased LF and context-dependent modulation of sIgA in HM. Detection of GIP in HM supports the hypothesis that intermittent gluten exposure may influence these immune components, potentially affecting neonatal immune maturation.