Inflammatory Mediators in Mastitis and Lactation Insufficiency

  • Wendy V. Ingman
  • Danielle J. Glynn
  • Mark R. Hutchinson


Mastitis is a common inflammatory disease during lactation that causes reduced milk supply. A growing body of evidence challenges the central role of pathogenic bacteria in mastitis, with disease severity associated with markers of inflammation rather than infection. Inflammation in the mammary gland may be triggered by microbe-associated molecular patterns (MAMPs) as well as danger-associated molecular patterns (DAMPs) binding to pattern recognition receptors such as the toll-like receptors (TLRs) on the surface of mammary epithelial cells and local immune cell populations. Activation of the TLR4 signalling pathway and downstream nuclear factor kappa B (NFkB) is critical to mediating local mammary gland inflammation and systemic immune responses in mouse models of mastitis. However, activation of NFkB also induces epithelial cell apoptosis and reduced milk protein synthesis, suggesting that inflammatory mediators activated during mastitis promote partial involution. Perturbed milk flow, maternal stress and genetic predisposition are significant risk factors for mastitis, and could lead to a heightened TLR4-mediated inflammatory response, resulting in increased susceptibility and severity of mastitis disease in the context of low MAMP abundance. Therefore, heightened host inflammatory signalling may act in concert with pathogenic or commensal bacterial species to cause both the inflammation associated with mastitis and lactation insufficiency. Here, we present an alternate paradigm to the widely held notion that breast inflammation is driven principally by infectious bacterial pathogens, and suggest there may be other therapeutic strategies, apart from the currently utilised antimicrobial agents, that could be employed to prevent and treat mastitis in women.


Mastitis Lactation insufficiency Inflammation Toll-like receptors 



Danger-associated molecular pattern






Microbe-associated molecular pattern


Nitric oxide synthase


Nuclear factor kappa b


Signal transducer and activator of transcription 5


Toll-like receptor


Tumour necrosis factor alpha



WVI is a NBCF/THRF Fellow, MRH is an ARC Fellow [ID:110100297].


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Wendy V. Ingman
    • 1
    • 2
    • 3
  • Danielle J. Glynn
    • 1
    • 2
    • 3
  • Mark R. Hutchinson
    • 4
  1. 1.Discipline of Surgery, School of Medicine, The Queen Elizabeth HospitalUniversity of AdelaideWoodvilleAustralia
  2. 2.Robinson Research InstituteUniversity of AdelaideAdelaideAustralia
  3. 3.School of Paediatrics and Reproductive HealthUniversity of AdelaideAdelaideAustralia
  4. 4.Discipline Physiology, School of Medical SciencesUniversity of AdelaideAdelaideAustralia

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