Developing ovine mammary terminal duct lobular units have a dynamic mucosal and stromal immune microenvironment.

ABSTRACT: The human breast and ovine mammary gland undergo striking levels of postnatal development, leading to formation of terminal duct lobular units (TDLUs). Here we interrogate aspects of sheep TDLU growth as a model of breast development and to increase understanding of ovine mammogenesis. The distributions of epithelial nuclear Ki67 positivity differ significantly between younger and older lambs. Ki67 expression is polarised to the leading edge of the developing TDLUs. Intraepithelial ductal macrophages exhibit periodicity and considerably increased density in lambs approaching puberty. Stromal macrophages are more abundant centrally than peripherally. Intraepithelial T lymphocytes are more numerous in older lambs. Stromal hotspots of Ki67 expression colocalize with immune cell aggregates tha

SUBMITTER: Nagy D 

PROVIDER: S-EPMC8379191 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature