Animal cell culture

Animal cell culture is a laboratory technique used in biology, medicine, and biotechnology where cells derived from multicellular eukaryotes are grown under controlled conditions. The process of animal cell culture can be used for various applications including the study of cellular processes, development of biological compounds, and in the production of vaccines and biopharmaceuticals.

History

The practice of animal cell culture began in the early 20th century. The first significant breakthrough in the field was achieved by Ross Granville Harrison in 1907, who successfully grew frog nerve fibers in vitro. Since then, the technique has evolved significantly, enabling the culture of various types of cells under laboratory conditions.

Techniques

Animal cell culture involves several key techniques:

• Primary culture: This involves the direct transfer of cells from a multicellular organism to a growth medium. These cells are obtained from tissues through mechanical or enzymatic methods.
• Cell line development: Once primary cells are cultured, they can be further subcultured to develop cell lines. These cell lines can be either finite (limited lifespan) or continuous (immortalized).
• Subculturing: Also known as passaging, this involves transferring cells from a crowded culture dish to a new one to provide more room for continued growth.

Types of Cultures

• Monolayer culture: Cells are grown on a flat surface where they spread and form a single layer.
• Suspension culture: Cells are grown in a medium, freely floating, which is suitable for cells that do not attach to the surface of the culture dish.

Media and Growth Conditions

The growth medium in animal cell culture provides essential nutrients such as amino acids, vitamins, minerals, and hormones. Media can be classified into two main types:

• Serum-containing media: Includes animal serum, which provides growth factors and nutrients.
• Serum-free media: Designed to reduce the variability and ethical concerns associated with the use of animal serum.

The environmental conditions such as temperature, pH, and gas concentration (typically 5% CO2) are also meticulously controlled to mimic physiological conditions.

Applications

Animal cell culture has numerous applications:

• Research: Used to study cellular processes, genetic regulation, and effects of drugs.
• Biopharmaceutical production: Production of vaccines, antibodies, and other therapeutic proteins.
• Toxicology testing: Used in drug development to assess the safety of compounds.

Challenges

Despite its vast applications, animal cell culture faces several challenges:

• Contamination: Bacterial, fungal, and viral contaminants can alter or halt the growth of cultures.
• Genetic instability: Cell lines, especially continuous ones, can undergo genetic changes over time, affecting the reliability of experimental results.

Future Directions

Advancements in animal cell culture continue to emerge, particularly with the integration of biotechnology and genetic engineering. Techniques such as CRISPR and stem cell technology are likely to further enhance the capabilities and applications of animal cell culture.