Karyotype analysis of murine macrophages for undergraduate students

The chapter, "Karyotype analysis of murine macrophages for undergraduate students" was written by the listed authors including Lynette B. Sigola (Douglas College Faculty). We have developed a karyotype analysis laboratory involving photomicroscopy which is suitable for use by students in biology courses at the undergraduate level. The laboratory activity uses the murine macrophage RAW 264.7 cell line maintained in vitro. In this laboratory activity, students benefit from an introduction to conditions required for cell culture (media, growth conditions, sterile technique), and use an inverted microscope to observe live cells in culture.
We describe the use of colchicine to arrest dividing cells in metaphase when chromosomes are most condensed. Cells are then harvested, treated in a hypotonic solution, fixed, and then dropped onto glass microscope slides. The slides are then stained and mounted and sealed. Photomicrographs are taken for analysis. We discuss the significance of cell preparation for microscopic analysis in engaging students as active learners.