Mucosal memory T cells in breastmilk are modulated by SARS-CoV-2 mRNA vaccination

We compared the phenotype, diversity, and antigen specificity of T cells in the breastmilk and peripheral blood of lactating individuals who received SARS-CoV-2 mRNA vaccination. Relative to blood, breastmilk contained higher frequencies of T effector and central memory populations that expressed mucosal-homing markers. T cell receptor (TCR) sequence overlap was limited between blood and breastmilk. Overabundant breastmilk clones were observed in all individuals, were structurally diverse, and contained CDR3 sequences with known epitope specificity including to SARS-CoV-2 Spike. Spike-specific TCRs were more frequent in breastmilk compared to blood and expanded in breastmilk following a third mRNA vaccine dose. Our observations indicate that the lactating breast contains a distinct T cell population that can be modulated by maternal vaccination with potential implications for infant passive protection.SummaryThe breastmilk T cell repertoire is distinct and enriched for SARS-CoV-2 Spike-specificity after maternal mRNA vaccination.

Axillary crystallizing galactocele masqueradingmalignancy:A rare case report andreview of literature

Galactocele are the most common benign lesion in lactating breast, whereas crystallizing galactocele are the rare variant. Axillary crystallizing galactocele are extremely rare to see , most commonly occur due to wrong breastfeeding technique. FNAC smear shows variety of crystals along with cysteine like crystals in a background of granular amorphous material or lipid micelles.

Low incidence of milk fistula with continued breastfeeding following radiologic and surgical interventions on the lactating breast

BACKGROUND: Milk fistula is a potential complication of radiologic and surgical procedures on the lactating breast, though its incidence is unknown. Some postulate that larger defects and/or closer proximity to the nipple increase the risk of fistula. OBJECTIVE: This study aimed to estimate the incidence of milk fistula and characterize risk factors in patients who continued breastfeeding after surgical or radiological procedures. METHODS: A retrospective cohort analysis of pregnant or lactating women treated at a multidisciplinary breast clinic from July 2016 through August 2019 was performed. Demographic and clinical variables were analyzed using ANOVA and Pearson’s Chi-square. RESULTS: Two pregnant and 43 lactating patients underwent 71 interventions. The incidence of milk fistula within one week of intervention was 1.4%. One fistula was diagnosed six days after retroareolar abscess drainage. The fistula closed successfully with continued breastfeeding. When categorized by the caliber of the most invasive intervention (large-caliber: mass excision, n = 7; medium-caliber: percutaneous drain insertion, n = 18; small-caliber: stab incision, aspiration, core needle biopsy, n = 20), patients were similar in age, race/ethnicity, weeks postpartum, and frequency of central versus peripheral interventions. The low incidence of fistula prevented quantitative evaluation of potential risk factors. CONCLUSIONS: Milk fistula is a rare occurrence following radiologic or surgical breast interventions performed during pregnancy or lactation. Indicated procedures should not be deferred, but periareolar approaches should be avoided when possible. Cessation of lactation is not mandatory for fistula closure, and continued breastfeeding should be recommended.

Severe Lactational Mastitis With Complicated Wound Infection Caused by Streptococcus pyogenes

Introduction Puerperal mastitis, a complication occurring during the breastfeeding period, is often caused by Staphylococcus aureus. Here we report on severe streptococcal mastitis in a lactating breast, with subsequent invasive disease and wound healing problems. Main issue The 41-year-old woman (G2, P2) presented at 2 weeks postpartum to our hospital with painful swelling and reddening of the left breast, in addition to fever and malaise, and complained about a nipple fissure on the left breast. Previously, her 4-year-old son was treated for an acute otitis media and her husband experienced flu-like symptoms. Management Due to the severity of the symptoms, Clindamycin antibiotic treatment was initiated intravenously. Streptococcus pyogenes was isolated in the milk. This strain is commonly known to cause infections of the upper respiratory tract, skin, and soft tissue, but rarely mastitis. Furthermore, the participant developed invasive disease with abscess formation and skin erosion with a milk fistula. Special dressing was applied to promote wound healing. The participant continued breastfeeding well into the child’s 2nd year of life. Conclusion This rare form of complicated mastitis with invasive disease caused by Streptococcus pyogenes called for an interdisciplinary approach. We want to draw attention to other pathogens causing mastitis and to alert health care workers to promote hygiene in lactating women to prevent transmission.

Transcriptional changes in the mammary gland during lactation revealed by single cell sequencing of cells from human milk

Findings from epidemiological studies suggest that breast cancer risk is influenced by parity in an age-dependent manner. However, human mammary tissue remodelling that takes place during pregnancy and lactation remain little understood due to the challenge of acquiring samples. Here, we present an approach to overcome this using single-cell RNA sequencing to examine viable primary mammary epithelial cells isolated from human milk compared to resting, non-lactating breast tissue. Thereby, we determined that separate to breast tissue, human milk largely contains epithelial cells belonging to the luminal lineage, as well as immune cells. Our data reveal the presence of two distinct secretory luminal cell clusters in milk which highly express luminal progenitor signatures akin to non-lactating breast tissue luminal cells. Taking advantage of the fact that both the resting and lactating mammary gland contain a luminal compartment, we focussed on comparing these transcriptomes and identified differences in mammary cell function and metabolism between these maturation states. These findings provide the basis to dissect human luminal differentiation and milk biosynthesis pathways that in the future, may be interrogated to determine how parity influences luminal cell metabolism and breast cancer risk.