Levels of innate immune factors in preterm and term mothers’ breast milk during the 1st month postpartum

Abstract

There is a paucity of data on the effect of preterm birth on the immunological composition of breast milk throughout the different stages of lactation. We aimed to characterise the effects of preterm birth on the levels of immune factors in milk during the 1st month postpartum, to determine whether preterm milk is deficient in antimicrobial factors. Colostrum (days 2-5 postpartum), transitional milk (days 8-12) and mature milk (days 26-30) were collected from mothers of extremely preterm (<28 weeks of gestation, n 15), very preterm (28 -<32 weeks of gestation, n 15), moderately preterm (32-<37 weeks of gestation, n 15) and term infants (37-41 weeks of gestation, n 15). Total protein, lactoferrin, secretory IgA, soluble CD14 receptor (sCD14), transforming growth factor-β2 (TGF-β2), α defensin 5 (HD5), β defensins 1 (HBD1) and 2, IL-6, IL-10, IL-13, interferon-γ, TNF-α and lysozyme (LZ) were quantified in milk. We examined the effects of lactation stage, gestational age, volume of milk expressed, mode of delivery, parity and maternal infection on milk immune factor concentrations using repeatedmeasures regression analysis. The concentrations of all factors except LZ and HD5 decreased over the 1st month postpartum. Extremely preterm mothers had significantly higher concentrations of HBD1 and TGF-β2 in colostrum than term mothers did. After controlling for other variables in regression analyses, preterm birth was associated with higher concentrations of HBD1, LZ and sCD14 in milk samples. In conclusion, preterm breast milk contains significantly higher concentrations of some immune proteins than term breast milk.

Innate Immunity and Breast Milk

“…This is particularly important in preterm infants who are at increased risk of late-onset sepsis. The hBD-1 was higher in preterm colostrum compared to term colostrum (99). Wang et al (102) also found that hBD-1 and hBD-2 were in higher concentration in mature preterm milk than mature term milk.…”

“…EGF has anti-inflammatory properties and is higher in preterm milk compared to full-term milk (24) The cytokine IL-10, with anti-inflammatory properties, was detected in lower amounts in breast milk for infants with increased risk of NEC (98). Trend et al reported that TGF-β2 concentrations in human milk were significantly higher in the extreme premature infant group compared to the term infant group (99). Castellote et al also reported that TGF-β2 was higher in preterm infants compared with term infants (100).…”

“…Wang et al (102) also found that hBD-1 and hBD-2 were in higher concentration in mature preterm milk than mature term milk. Armogida et al and Trend et al both found that human α-defensin 5 levels were not affected by preterm birth, which suggests that these defensins are differentially regulated (99, 103). The amount of LF in human milk does not seem to be affected by gestational age (99) but is more dependent on milk volume expressed.…”

Protective Role of Passively Transferred Maternal Cytokines against Bordetella pertussis Infection in Newborn Piglets

“…Intriguingly, maternal cytokine levels (e.g., tumor necrosis factor alpha [TNF-␣], monocyte chemoattractant protein 1 [MCP-1], and interleukin-10 [IL-10]) during gestation correlate with the newborn's cytokine levels at up to 1 year of age (23), reinforcing the synchronized polarization of the maternal and fetal immune systems. More recent studies indicated higher levels of immune proteins, such as host defense peptides and cytokines, in preterm mothers' breast milk and the potential influence of these cytokines on the immune system of the newborn (24).…”

Clássicos e novos biomarcadores de sepse neonatal

“…43, n. 3, p. 1-8, nov./dez, 2017 para sepse precoce, porém IL-6 demonstrou melhor sensibilidade e correlação com mortalidade acima de 78.2pg/mL.32 Mães com bebês pré-termos (<28semanas) demonstraram altas concentrações de proteínas protetoras no colostro, tais como: lisozima, HBD1, sCD14 e TGF-β2, comparado a mães de neonatos nascidos a termo. 33 Tais fatores maternos, inclusive citocinas, contribuem com a proteção do recém-nascido no período pré-natal e pós-natal. No entanto, o uso de corticoides pode influenciar no perfil e taxa desses componentes imunológicos no pós-natal.…”