Cell Culture Applications

Microdissection Techniques

• Allow selected cells to be isolated from tissue slices
• Applications include:
  • Embryonic organ culture
  • Study of cancer cells
  • Cell-virus relations
  • Cytogenetic research
  • Cell-cell interactions
  • Cell nutrition

Embryonic Stem Cells

• Most promising cell lines for medical applications
• Derived from inner cell mass of early mouse embryos
• Can proliferate indefinitely
• Can give rise to all cell types in the body
• Can be used to replace and repair damaged mature human tissues
• Potential therapeutic applications:
  • Muscular dystrophy
  • Parkinson's disease
  • Type I diabetes

Model Organisms

• Escherichia coli (E. coli): best understood cell in biology
• Saccharomyces cerevisiae (yeast): most frequently used single-cell eukaryote
• Studies with bacteria and yeast established basic principles of molecular biology

Cell-Cell Fusion

• Hybrid cells produced by fusion of animal cells
• Cell fusion: membrane merging and cytoplasmic mixing of two cell types
• Examples: human cell and mouse cell fusion

Cell Size and Number

• Human body composed of trillions of cells
• Size of a typical animal cell: 20-30 µm
• Largest cell: human egg (150-200 µm)
• Smallest cell: granular cells of cerebellum (4-5 µm)

Methods for Examining Cells

• Examination of the cell as a whole (without disruption)
• Examination of living cells (fresh tissues)
• Examination of killed and preserved tissues and cells
• Fractionation of cells and analyzing their molecules

Cell Culture

• Isolating cells and growing them in culture
• Living cells can be suspended in an appropriate liquid (e.g. saline solution)
• Prolonged study of living cells can be made by culturing them in solutions containing necessary nutrients
• First tissue culture (1907): Ross Harrison, isolated fragments of spinal cord of a frog

Culture Conditions

• Medium supplying essential nutrients (amino acids, carbohydrates, vitamins, minerals)
• Growth factors
• Hormones
• Gases (O2, CO2)
• Regulated physico-chemical environment (pH, osmotic pressure, temperature)
• Most cells are anchorage-dependent and require a solid or semi-solid substrate

Primary Cell Culture and Cell Lines

• Primary cell culture: derived from normal animal cells, limited life span, divide 25-50 times, and then stop dividing (cell senescence)
• Cell lines: eukaryotic cell lines, widely used for experiments, transformed cells, grow indefinitely in culture (immortal cells)

This quiz covers various applications of cell culture techniques, including the study of embryonic development, cancer cells, and cytogenetic research.