Active free secretory component and secretory IgA in human milk: do maternal vaccination, allergy, infection, mode of delivery, nutrition and active lifestyle change their concentrations?

Herein, we report the abundance and prevalence of HMO-metabolizing genes, specifically those of Bifidobacterium infantis, in fecal samples from human infants. Forty dyads were enrolled, and each mother collected a fecal sample from her infant at six months of age. Genomic DNA was extracted, and quantitative real-time PCR was used to determine gene abundance. The mode of delivery was not associated with gene abundance. Several gene regions, Sia (a sialidase), B. inf (16S), and GH750 (a glycoside hydrolase), were more abundant in the feces of human milk-fed infants (p < 0.05). Others, Sia and HC bin (16S), tended to be less abundant when a larger percentage of an infant’s diet consisted of solids (p < 0.10). When accounting for solid food intake, human milk exposure was positively associated with Sia and B. inf (p < 0.05) and tended to be related to the abundance of the GH750 and HC bin (p < 0.10) gene regions. With further development and validation in additional populations of infants, these assays could be used to group samples by dietary exposure even where no record of dietary intake exists. Thus, these assays would provide a method by which infant human milk intake can be assessed quickly in any well-equipped molecular biology laboratory.

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Longitudinal Changes in the Concentration of Major Human Milk Proteins in the First Six Months of Lactation and Their Effects on Infant Growth

Nutrients ◽

10.3390/nu13051476 ◽

2021 ◽

Vol 13 (5) ◽

pp. 1476

Author(s):

Jian Zhang ◽

Ai Zhao ◽

Shiyun Lai ◽

Qingbin Yuan ◽

Xiaojiang Jia ◽

...

Keyword(s):

Human Milk ◽

Maternal Education ◽

Mode Of Delivery ◽

Milk Proteins ◽

Protein Composition ◽

Infant Growth ◽

Term Infants ◽

Longitudinal Changes ◽

Milk Samples ◽

The Impact

Our knowledge related to human milk proteins is still limited. The present study determined the changes in multiple human milk proteins during the first six months of lactation, investigated the influencing factors of milk proteins, and explored the impact of milk proteins on infant growth. A total of 105 lactating women and their full-term infants from China were prospectively surveyed in this research. Milk samples were collected at 1–5 days, 8–14 days, 1 month, and 6 months postpartum. Concentrations of total protein and α-lactalbumin were measured in all milk samples, and concentrations of lactoferrin, osteopontin, total casein, β-casein, αs−1 casein, and κ-casein were measured in milk from 51 individuals using ultra performance liquid chromatography coupled with mass spectrometry. The concentration of measured proteins in the milk decreased during the first six months of postpartum (p-trend < 0.001). Maternal age, mode of delivery, maternal education, and income impacted the longitudinal changes in milk proteins (p-interaction < 0.05). Concentrations of αs−1 casein in milk were inversely associated with the weight-for-age Z-scores of the infants (1 m: r −0.29, p 0.038; 6 m: r −0.33, p 0.020). In conclusion, the concentration of proteins in milk decreased over the first six months postpartum, potentially influenced by maternal demographic and delivery factors. Milk protein composition may influence infant weights.

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Simultaneous pasteurization and homogenization of human milk by combining heat and ultrasound: effect on milk quality

Journal of Dairy Research ◽

10.1017/s0022029909990483 ◽

2010 ◽

Vol 77 (2) ◽

pp. 183-189 ◽

Cited By ~ 38

Author(s):

Charles Czank ◽

Karen Simmer ◽

Peter E Hartmann

Keyword(s):

Human Milk ◽

Milk Proteins ◽

Food Preservation ◽

Secretory Iga ◽

Bioactive Components ◽

Laser Scattering ◽

Milk Samples ◽

Donor Human Milk ◽

Preservation Technique ◽

Ultrasound Effect

The combination of ultrasound and heat (thermoultrasound) is an emerging food preservation technique that retains higher quantities of bioactive components compared with current thermal pasteurization practice, but has not yet been assessed for pasteurizing human milk. Artificially contaminated human milk samples were treated with ultrasound (20 kHz, 150 watts) with and without heating. The retention of four human milk proteins was quantified by biochemical assay and laser scattering particle sizing was used to determine the extent of homogenization. While ultrasonic treatment was effective at inactivating Escherichia coli (D4 °C=5·94 min), Staphylococcus epidermidis exhibited resistance (D4 °C=16·01 min). Thermoultrasonic treatment was considerably more effective (Esch. coli D45 °C=1·74 min, D50 °C=0·89 min; Staph. epidermidis D45 °C=2·08 min, D50 °C=0·94 minutes) with a predicted retention (2·8 min treatment, 50°C) of secretory IgA lysozyme, lactoferrin and bile salt stimulated lipase of 91, 80, 77, and 45%, respectively. Homogenization of the milk samples occurred after 5 min and 2 min of ultrasonic and thermoultrasonic treatment, respectively. Thermoultrasonic treatment is an effective method for pasteurizing donor human milk and retaining a greater proportion of bioactive components compared with current practices. However, further studies are required to assess the practicality of applying this technique routinely to donor human milk.

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Secretory Anti-Giardia lamblia Antibodies in Human Milk: Protective Effect Against Diarrhea

PEDIATRICS ◽

10.1542/peds.93.1.28 ◽

1994 ◽

Vol 93 (1) ◽

pp. 28-31

Author(s):

Juan N. Walterspiel ◽

Ardythe L. Morrow ◽

Larry K. Pickering ◽

Guillermo M. Ruiz-Palacios ◽

M. Lourdes Guerrero

Keyword(s):

Human Milk ◽

Protective Effect ◽

Immunosorbent Assay ◽

Giardia Lamblia ◽

Diarrheal Disease ◽

Secretory Iga ◽

Enzyme Linked Immunosorbent Assay ◽

Giardia Infection ◽

Maternal Milk ◽

Milk Samples

Objective. To determine whether anti-Giardia lamblia secretory IgA (sIgA) antibodies in human milk protect infants from acquisition of or symptoms associated with Giardia infection. Methods. One hundred ninety-seven Mexican mother/infant pairs were followed weekly from birth for diarrheal disease and feeding status. Infant stool specimens were collected weekly and were cultured for bacterial pathogens and tested for Giardia and rotavirus by enzyme-linked immunosorbent assay. Maternal milk samples were collected weekly for 1 month postpartum and monthly thereafter. To determine the protective effect of anti-Giardia sIgA in milk against infection and against diarrhea due to Giardia, milk samples from mothers of infected infants and appropriately matched controls were assayed for anti-Giardia sIgA by enzyme-linked immunosorbent assay. Results. Asymptomatic, infected infants ingested significantly (P = .046) higher amounts of milk anti-Giardia sIgA compared with symptomatic, infected infants. However, milk anti-Giardia sIgA concentrations did not differ between Giardia-infected and noninfected infants. Conclusion. The amount of anti-Giardia sIgA in human milk was associated with prevention of symptoms of diarrhea due to Giardia, but not with acquisition of the organism.

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Studies on human secretory IgA (II). Comparative studies on a fragment of secretory component derived from secretory IgA and fragments obtained by enzymatic digestion of free secretory component

Molecular Immunology ◽

10.1016/0161-5890(73)90138-7 ◽

1973 ◽

Vol 10 (2) ◽

pp. 73-80 ◽

Cited By ~ 1

Author(s):

K Kobayashi

Keyword(s):

Comparative Studies ◽

Enzymatic Digestion ◽

Secretory Component ◽

Secretory Iga

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Melatonin Content of Human Milk: The Effect of Mode of Delivery

Breastfeeding Medicine ◽

10.1089/bfm.2020.0157 ◽

2020 ◽

Vol 15 (9) ◽

pp. 589-594

Author(s):

Sonia Aparici-Gonzalo ◽

Álvaro Carrasco-García ◽

Marie Gombert ◽

Joaquín Carrasco-Luna ◽

Gonzalo Pin-Arboledas ◽

...

Keyword(s):

Human Milk ◽

Mode Of Delivery

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Secretory Immunoglobulin a in Oral and Respiratory Passages in Man

Annals of Otology Rhinology & Laryngology ◽

10.1177/0003489475084s2001 ◽

1975 ◽

Vol 84 (20_suppl) ◽

pp. 1-23 ◽

Cited By ~ 13

Author(s):

Goro Mogi

Keyword(s):

Immunoglobulin A ◽

Secretory Component ◽

Secretory Iga ◽

Secretory Cells ◽

Antigenic Relationship ◽

Serum Iga ◽

Human Colostrum ◽

Specific Antisera ◽

Antigenic Relationships ◽

Secretory Immunoglobulin

Secretory IgA (SIgA) is the predominant immunoglobulin in certain external secretions and may have an important role in immunological mucosal resistance. SIgA differs in chemical and immunological properties from serum IgA. The present study was undertaken to investigate the antigenic relationship between SIgA, free secretory component (FSC) and serum IgA and the localization of SIgA as well as other immunological classes in tissues of oral and respiratory passages by use of immunofluorescence technique. SIgA and FSC were highly purified from human colostrum and rabbit anti-SIgA and anti-SC antisera were prepared. On the basis of antigenic relationships between SIgA, FSC and serum IgA, it was emphasized that individual specific antisera for SC and IgA and/or SIgA should be used in immunochemical or immunohistological investigations for SIgA. The present study failed to detect SC determinants in palatine and lingual tonsils. However, it was evident that cells present in the pharyngeal tonsillar epithelium contain SC determinants. SC molecules may be synthesized in certain secretory cells of mucous membrane and glandular epithelium and the combining of SC with IgA could occur in the cytoplasm of epithelial cells, the intercellular spaces and/or in the lumens of glandular acini and ductules.

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