User:NolanOriger/Cell Engineering

Cell engineering is the purposeful process of adding, deleting, or modifying genetic sequences in living cells to achieve biological engineering goals such as altering cell production, changing cell growth and proliferation requirements, adding or removing cell functions, and many more. Cell engineering often makes use of recombinant DNA technology to achieve these modifications as well as closely related tissue engineering methods. Cell engineering can be characterized as an intermediary level in the increasingly specific disciplines of biological engineering which includes organ engineering, tissue engineering, cell engineering, protein engineering, and genetic engineering.

Improving production of natural cellular products
One general form of cell engineering involves altering natural cell production to achieve a more desirable yield or shorter production time. A possible method for changing natural cell production includes boosting or repressing genes that are involved in the metabolism of the product. For example, researchers were able to overexpress transporter genes in hamster ovary cells to increase monoclonal antibody yield. Another approach could involve incorporating biologically foreign genes into an existing cell line. For example, E.Coli, which synthesizes ethanol, can be modified using genes from Zymomonas mobilis to make ethanol fermentation the primary cell fermentation product.

Altering cell requirements
Another beneficial cell modification is the adjustment of substrate and growth requirements of a cell. By changing cell needs, the raw material cost, equipment expenses, and skill required to grow and maintain cell cultures can be significantly reduced. For example, scientists have used foreign enzymes to engineer a common industrial yeast strain which allows the cells to grow on substrate cheaper than the traditional glucose. Because of the biological engineering focus on improving scale-up costs, research in this area is largely focused on the ability of various enzymes to metabolize low-cost substrates.

Augmenting cells to produce new products
Closely tied with the field of biotechnology, this subject of cell engineering employs recombinant DNA methods to induce cells to construct a desired product such as a protein, antibody, or enzyme. One of the most notable examples of this subset of cellular engineering is the transformation of E. Coli to transcript and translate a precursor to insulin which drastically reduced the cost of production. Similar research was conducted shortly after in 1979 in which E. Coli was transformed to express human growth hormone for use in treatment of pituitary dwarfism. Finally, much progress has been made in engineering cells to produce antigens for the purpose of creating vaccines.

Etymology
The phrase "cell engineering" was first used in a published paper in 1968 to describe the process of improving fuel cells. The term was then adopted by other papers until the more specific "fuel-cell engineering" was used.

The first use of the term in a biological context was in 1971 in a paper which describes methods to graft reproductive caps between algae cells. Despite the rising popularity of the phrase, there remains unclear boundaries between cell engineering and other forms of biological engineering.