Clonal cell lines were isolated from mammary gland tissue epithelial cell cultures of lactating cows. Early passage clonal bovine mammary epithelial cells (clone LMH17) gave rise to several established cell lines (MAC-T lines) after being cotransfected with plasmids containing the temperature sensitive mutant SV40 large T antigen gene (pBAPSV40TtsA58) and the bacterial phosphotransferase gene (pSV2-neo). Unlike other cell types which were transformed after being transfected with SV40, MAC-T cells maintained many characteristics of non-transformed cells: MAC-T cells were serum and anchorage dependent, showed contact inhibition, and were not tumorigenic in immunodeficient mice. However, Southern transfer analysis revealed an integrated SV40 gene and cells showed no senescence after 50 passages. These cells are morphologically indistinguishable from parental LMH17 cells and retain the typical morphology of mammary epithelial cells. Positive cytokeratin immunostaining and the absence of vimentin staining indicated that these cells were epithelial in origin. / MAC-T cells grew rapidly on plastic substratum with a doubling time of approximately 17 hours and became differentiated when grown on floating collagen gels in the presence of prolactin. The differentiated phenotype was characterized to include (1) the ability to form secretory domes with a lumen from a pavement of columnar cells; (2) increased casein mRNA abundance; (3) increased alpha S and beta casein secretion; (4) increased number and size of casein secretory vesicles; and (5) increased lactose synthesis and secretion.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.60426 |
| Date | January 1990 |
| Creators | Huynh, The Hung |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Animal Science.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001171941, proquestno: AAIMM67560, Theses scanned by UMI/ProQuest. |
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