Learning Outcomes
By the end of the course, students are expected to be able to:
1.Explain the various cell lines used in mammalian tissue culture and their origins and uses
2.Explain the various components of cell and tissue culture media;
3.Explain the various steps taken to establish and optimize media for particular purposes in different species and cell lines;
4.Grow mammalian cells and tissues in the laboratory;
5.Apply different techniques to harvest and propagate mammalian cells for disease investigation or biological product development
Cell and tissue culture refers to the technique of growing cells, tissues, or organs outside of their natural biological context, under controlled laboratory conditions. This method is widely used in research, medicine, and biotechnology for studying cellular behavior, developing treatments, and producing biological products.
Concepts in Cell and Tissue Culture
- A cell is defined as the smallest, basic unit of life that is responsible for all of life’s processes.”
- Cells are the structural, functional, and biological units of all living beings. Hence, they are known as the building blocks of life
- A tissue is a group of cells, in close proximity, organized to perform one or more specific functions
- There are four basic tissue types defined by their morphology and function: epithelial tissue, connective tissue, muscle tissue, and nervous tissue
- An organ (from the Latin “organum” meaning an instrument or tool) is a collection of tissues that structurally form a functional unit specialized to perform a particular function.
- Cell culture: The process of growing and maintaining cells derived from tissues in a controlled environment, usually in a liquid medium.
- Tissue culture: Refers to the growth of tissues or small organ-like structures, often maintaining some of their natural organization and function.
Historical Background
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- Cell culture began in the early 20th century, with significant advancements made by scientists like Ross Harrison, who demonstrated the growth of nerve fibers outside the body.
- The first immortalized cell line, HeLa cells, was established in 1951 from cervical cancer cells of Henrietta Lacks.
- 1878: Claude Bernard proposed that physiological systems of an organism can be maintained in a living system after the death of an organism
- 1885: Roux maintained embryonic chick cells in a saline culture
- 1897: Loeb demonstrated the survival of cells isolated from blood and connective tissue in serum and plasma
- 1903: Jolly observed cell division of salamander leucocytes in vitro
- 1907: Ross Harrison cultivated frog nerve cells in a lymph clot held by the ‘hanging drop’ method and observed the growth of nerve fibers in vitro for several weeks. He was considered by some as the father of cell culture
- 1910: Burrows succeeded in long term cultivation of chicken embryo cell in plasma clots. He made detailed observation of mitosis
- 1911: Lewis and Lewis made the first liquid media consisted of sea water, serum, embryo extract, salts and peptones. They observed limited monolayer growth.
- 1913: Carrel introduced strict aseptic techniques so that cells could be cultured for long periods.
- 1916: Rous and Jones introduced proteolytic enzyme trypsin for the subculture of adherent cells.
- 1923: Carrel and Baker developed ‘Carrel’ or T-flask as the first specifically designed cell culture vessel. They employed microscopic evaluation of cells in culture.
- 1927: Carrel and Rivera produced the first viral vaccine – Vaccinia.
- 1933: Gey developed the roller tube technique (tissue fragments fastened to the inner wall of a test tube
- 1940s: The use of the antibiotics penicillin and streptomycin in culture medium decreased the problem of contamination in cell culture.
- 1948: Earle isolated mouse L fibroblasts which formed clones from single cells. Fischer developed a chemically defined medium, CMRL 1066.
- 1952: Gey established a continuous cell line from a human cervical carcinoma known as HeLa (Helen Lane) cells. Dulbecco developed plaque assay for animal viruses using confluent monolayers of cultured cells.
- 1954: Abercrombie observed contact inhibition: motility of diploid cells in monolayer culture ceases when contact is made with adjacent cells.
- 1955: Eagle studied the nutrient requirements of selected cells in culture and established the first widely used chemically defined medium.
- 1961: Hayflick and Moorhead isolated human fibroblasts (WI-38) and showed that they have a finite lifespan in culture.
- 1964: Littlefield introduced the HAT medium for cell selection.
- 1965: Ham introduced the first serum-free medium which was able to support the growth of some cells.
- 1965: Harris and Watkins were able to fuse human and mouse cells by the use of a virus.
- 1975: Kohler and Milstein produced the first hybridoma capable of secreting a monoclonal antibody.
- 1978: Sato established the basis for the development of serum-free media from cocktails of hormones and growth factors.
- 1982: Human insulin became the first recombinant protein to be licensed as a therapeutic agent.
- 1985: Human growth hormone produced from recombinant bacteria was accepted for therapeutic use.
- 1986: Lymphoblastoid γIFN licensed.
- 1987: Tissue-type plasminogen activator (tPA) from recombinant animal cells became commercially available.
- 1989: Recombinant erythropoietin in trial.
- 1990: Recombinant products in clinical trial (HBsAG, factor VIII, HIVgp120, CD4, GM-CSF, EGF, mAbs, IL-2).
Major development’s in cell culture technology
- 1907: Cell culture started off as tissue culture with the development of the “hanging drop technique” by Ross Harrison, whereby a small piece of tissue was placed in a drop of medium (including serum), and cells migrated from the tissue into the surrounding environment.
- 1916: First development was the use of trypsin to remove adherent cells to subculture further from the culture vessel -By Rous and Jones.
- 1940s: Second development was the use of antibiotics which inhibits the growth of contaminants –by Selman Waksman.
- 1948: Third development was the use of chemically defined culture medium (CMRL 1066) -By Fischer
- 1955: Development of the first widely used chemically defined medium (Eagle’s minimal essential medium, EMEM)– By Harry Eagle