Article

Do inflammatory cells participate in mammary gland involution?

Department of Pediatrics, National Jewish Medical and Research Center, 1400 Jackson Street, Denver, Colorado 80206, USA.
Journal of Mammary Gland Biology and Neoplasia (Impact Factor: 5). 05/2002; 7(2):163-76. DOI: 10.1023/A:1020351919634
Source: PubMed

ABSTRACT The processes by which the involuting mammary gland clears residual milk and milk fat, as well as apoptotic cells, have gone largely unstudied in the modern literature. Here we review the evidence for and against the involvement of professional phagocytes of hematopoietic lineage in this process. Additionally we present evidence that mammary epithelial cells themselves are capable of phagocytosis and may be responsible for the majority of apoptotic cell and residual milk clearance during murine involution. In this scheme these cells regulate their cytokine production in response to apoptotic cells in a manner similar to other cells, including macrophages. The ensuing model describes a process of involution that actively suppresses an inflammatory response in the gland, allowing for effective tissue remodeling and damage prevention.

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