Breast Milk: Influence of the Micro-transcriptome Profile on Atopy in Children Over Time

Infant development of one or more of the following atopic conditions at any point during the first 12 months (48 weeks) after birth: atopic dermatitis, reactive airway (wheezing), or food allergy. When possible specific allergy will be confirmed with IgE serum testing at 48 weeks.

Food allergy: defined by affirmative parent response to "Has your baby ever had problems caused by food, such as an allergic reaction, sensitivity, or intolerance?" on the Infant Feeding Practices (IFP) Survey, administered at 4, 16, 24, and 48 weeks. Confirmed by serum RAST testing at 48 weeks.

Defined by an affirmative parent response to "Has your baby had wheezing in the chest or bronchitis or whistling during his/her first 12 months of life?" on the International Study of Wheezing in Infants (EISL-WQ) Survey, administered at 48 weeks. Confirmed by serum RAST testing with the Northeast Allergen Panel at 48 weeks. Applied to Pediatric Asthma Risk Score criteria.

Defined by ICD-10 diagnosis and quantified by SCORing Atopic Dermatitis (SCORAD) Survey at 4, 16, 24, or 48 weeks (<25: mild, 25-50: moderate, >50: severe).

For each infant, exposure to individual small non-coding RNAs that are robustly expressed (counts > 10 in >90% of samples with RNA sequencing depth of 5 million reads) in maternal breast milk (MBM) will be calculated as follows (example for hsa-miR-26a):

• Exposure in weeks 0-3: Volume of MBM/day x [miR-26a] (ppm) x 28 days (or until breastfeeding ceased) x Proportion of feeds consisting of MBM plus...
• Exposure in weeks 4-15: Volume of MBM/day x [miR-26a] (ppm) x 84 days (or until breastfeeding ceased) x Proportion of feeds consisting of MBM plus...
• Exposure in weeks 16-23: Volume of MBM/day x [miR-26a] (ppm) x 56 days (or until breastfeeding ceased) x Proportion of feeds consisting of MBM = Total miR-26a exposure (ppm) in the first 6 months

Documented for mother-infant dyads at 4-weeks post delivery using the National Survey of Lead hazards and Allergens in Housing (NSLAH) Survey, developed by the Department of Housing and Urban Development in coordination with the National Institute of Environmental Health. The survey asks about the age of housing, number of occupants, heating source, and the presence/absence of air conditioning, air filtration system, mold/mildew, dehumidifier, pets, cockroaches, mice/rats, and cigarette smokers in the home.

Documented at 0, 4, and 16 weeks using a modified version of the Diet History Questionnaire (DHQ), developed by the National Cancer Institute. Briefly, the survey measures servings of: hot/cold cereals, milk, soda, fruit juice, coffee/tea, sweetened fruit/sports drinks, fruit, green leafy vegetables, fried potatoes, other potatoes, beans, rice, salsa, pizza, tomatoes, cheese, red meat, processed meat, bread, chocolate, doughnuts/muffins, baked goods, ice cream, and pop-corn. Responses are recorded as: never, once per month, 2-3 times per month, once per week, 2 times per week, 3-4 times per week, once per day, 2-3 times per day, and 3-4 times or more per day.

The Brief Infant Sleep Questionnaire (BISQ) will be administered at 4, 16, 24, and 48-weeks. Nine qualitative questions about infant sleep practices are recorded, including: sleeping arrangement, sleep position, time spent during sleep (in hours), time spent in daytime sleep (in hours), average number of night time awakenings, amount of night-time wakefulness, sleep onset latency, mode of sleep initiation, time of sleep initiation. Affirmative parental response to, "Do you consider your child's sleep to be a problem?" will be used to dichotomize those with atypical sleep habits.

A modified version of the Infant Colic Scale (ICS) will be administered at 4-weeks. This modified scale assesses 12 items on a six point Likert scale (strongly disagree, disagree, slightly disagree, slightly agree, agree, strongly agree). A higher score portends greater likelihood of colic, with average score across the 12 items of >2.9 being consistent with colic. Questions generally assess gastrointestinal symptoms, infant temperament, and parent-infant interaction.

Weight for length z-score will be recorded from the electronic medical record at 0, 4, 16, 24, and 48 weeks, as well as 2, 3, 4, and 5 years after delivery. The change in weight for length z-score from 0-48 weeks will be the primary outcome, where a positive z-score change will indicate relative weight increase, and a negative z-score change will indicate relative weight decrease.

Survey of Wellbeing in Young Children (SWYC) scores will be abstracted from the electronic medical record at 9, 18, and 30-months. Children with a total score <12 (at 9-months of age), <9 (at 18-months of age), or <11 (at 30-months of age) will be defined as those with potential developmental delays.

Child development of one or more of the following atopic conditions at any point during the first 5 years after birth:

• Atopic dermatitis
• Wheezing
• Food allergy
• Allergic rhinitis
• Allergic conjunctivitis
• Asthma

All defined by clinical documentation in the child's medical problem within the electronic medical record.

Small non-coding RNAs (including bacterial RNAs) will be quantified in stool from each infant at 0-weeks and 48-weeks using high throughput RNA sequencing.

Small non-coding RNAs (including bacterial RNAs) will be quantified in saliva from each infant at 0, 4, 16, 24, and 48-weeks using high throughput RNA sequencing.

TH1 and TH2 cytokines, including CCL5, IFN-gamma, IL-1, IL-4, IL-5, IL-6, IL-8, IL-10, IL-13, eotaxin, TNF-alpha, TGF-beta-1, and TGF-beta-2 will be measured in infant saliva using a luminex assay.

T-helper (TH-)1 and TH-2 cytokines, including C-C Motif Chemokine Ligand (CCL)-5, interferon (IFN)-gamma, interleukin (IL)-1, IL-4, IL-5, IL-6, IL-8, IL-10, IL-13, eotaxin, tumor necrosis factor (TNF)-alpha, transforming growth factor (TGF)-beta-1, and TGF-beta-2 will be measured in maternal breast milk using a luminex assay. Serotonin and melatonin will also be interrogated.

Deoxy-ribonucleic acid will be extracted from infant saliva for interrogation of single nucleotide polymorphisms and copy number variants related to atopy risk.

Deoxy-ribonucleic acid will be extracted from maternal saliva for interrogation of single nucleotide polymorphisms and copy number variants related to atopy risk.

Specific IgEs will be measured in the serum of all infants who meet atopy criteria at 48-weeks, including 1) aeroallergens (bermuda grass, timothy grass, cockroach, penicillium notatum, cladosporium herbarum, aspergillus fumigatus, mucor racemosus, alternaria tenuis, box elder maple, common silver birch, oak, elm, walnut tree, maple leaf sycamore, cottonwood poplar, white ash, mulberry, red cedar, ragweed, mugwort, pigweed, sheep sorrel, cat dander, dog dander, mouse); 2) food allergens (cow's milk, wheat, almond, shrimp, egg yolk, egg white, codfish, sesame seed, soybean, hazelnut, tuna, salmon, scallop, pecan, cashew, walnut, and peanut); and 3) total IgE.