(1315-D) Homogeneous Luminescent Immunoassays for Proliferation and Senescence
Tuesday, February 6, 2024
2:00 PM – 3:00 PM EST
Location: Exhibit Halls AB
We have developed homogeneous, luminescent immunoassays for simple and rapid determination of Ki-67 and uPAR levels in 96-well format, thereby enabling efficient and quantitative assessment of proliferation and senescence in mammalian cell culture. Ki-67 is a nuclear protein widely used as a marker of proliferation due to its pervasive expression in cycling cells but absence from non-dividing (G0) cells. In contrast, urokinase plasminogen activator receptor (uPAR) is a cell-surface protein whose expression was recently reported to increase significantly with the induction of senescence. Application of Lumitâ„¢ technology enabled development of no-transfer, no- wash immunoassays for Ki-67 (lytic) and uPAR (nonlytic) determinations in cell wells. Treatment of human CD8+ T cells with a panel of T cell activators with known mitogenic activity produced dramatic upregulation of Ki-67, including donor-dependent response profiles. In contrast, treatment of HCT 116 colorectal cancer cells with antiproliferative compounds produced significant reductions in Ki-67 levels. In these same HCT 116 cells, more extended treatment produced upregulation of cell-surface uPAR, consistent with the known induction of senescence. These homogeneous Ki-67 and uPAR immunoassays provide an efficient means to quantitatively assess changes in cell proliferation and senescence in cell culture models.