Threat of Bacteria and Gene Defects on Pharmaceutical Value of Cow Milk in Producing Human Antibodies, Proteins that Fight Pathogens (Part. 2)

Results

     The success of the USDA/Agricultural Research Service is revealed through the numbers:

“71 percent of the mammary glands that were exposed to S. aureus from nontransgenic animals became infected--compared to only 14 percent for the transgenic animals” (Bliss, 2005, par.8). 

The scientists from the article of the Times (2017) report that “when calves that were modified were tested, they showed an increased resistance to the TB bacterium” (par. 6). In Xu et al. (2011)’s experiment, after introducing the environmental impact in transgenic cows, a report records on page 1044 that:

“GE–cows expressed high content of these three proteins, the highest content was up to 25.96 μg/ml of lysozyme (paper being submitted), 3.4 mg/ml of lactoferrin (Yang et al. 2008), 1.55 mg/ml alpha lactalbumin (Wang et al. 2008).”

While the proteins in human milk are 0.03–3 mg/ml (lysozyme), 2.0–5.8 mg/ml (lactoferrin), 1.8–3.1 mg/ml (alpha-lactalbumin). The proteins of the milk from transgenic cows after the experiment is utterly higher than the ones in bovine milk whose amounts are 0.05–0.22 μg/ml (lysozyme), 0.03–0.49 mg/ml (lactoferrin), and 1.47 mg/ml (alpha-lactalbumin).

Discussion

    Genetically engineered cows with diseases are the biggest liabilities in pharmaceutical development. Being aware of this, scientists have tried their best to control the loose of bacteria attack.

     One of the common diseases, tuberculosis, can now be prevented by using “gene editing tool called Crispr Cas9 to remove and replace pieces of the genetic code, opening up the prospect of a future where culls may not be necessary” (Whipple, 2017, par. 3) with no side-effects. Another common disease is the “widespread bacterial infection called mastitis” (Bliss, 2005, par. 1) now have a positive, temporary solution. With the use of gene-transfer technologies, Robert J. Wall and his team were trying to build “a transgene--genetic material” to produce “a naturally occurring, antimicrobial protein called lysostaphin” (Bliss, 2005, par. 4). Although this results in more than 80 percent animals and cows are protected, the milk containing lysostaphin will have to pass to the careful food safety testing by the government. This reveals that not all transgenic cows who are treated can provide standard medical products.

     Why vaccines are no longer the top priority of development and studying? Many institutions such as Tractor Supply Company (n.d) suggest using various antibiotics and vaccines for the cattle: “Biologicals are products designed to stimulate an animal’s immune system in response to an invasion of viruses or bacteria” (par. 6). Despite that, not every bacteria can be prevented by this way, especially the mastitis-causing bacteria. Rosalie Marion Bliss (2005) writes that “vaccines, antibiotics and a cow's own immune system cannot effectively fight the bacterium Staphylococcus aureus, a major cause of mastitis” (par. 3). Therefore, the gene assessment is more focused on than the development of biologicals and antibodies.

     Besides the diseases, gene deficits also cause problems for the medical products of transgenic cows. Interpreting this phenomenon, Xu et al. (2011) points out that transgenic cows can be affected by the environment, especially bacteria from soils, because of their gene system (p. 1044). Moreover, the cause can be from the gene of their families. How can we produce a transgenic cow without the gene deficits?

     The results from Xu et al. (2011)’s paper have proved the efficiency of assessing “the potential environmental impact of transgenic cows” before introducing them into the environment. This makes up the gene that naturally helps them survive in the environment like other animals. The experiment successfully shows the number of high proteins in transgenic cows milk. Another suggestion from the Veterinary World (2008)’s paper is to “mate ‘normal’ cows with genetically modified bulls so that the next generation of calves will produce the desired protein” (p. 319). Although this sounds ideal, this method contains a high risk of being attacked by the bacteria. According to Xu et al. (2011), the appropriate method is to insert the extra gene into cows:

“The most likely environment for HGT (Horizontal gene transfer) to occur is the gastrointestinal (GI) tract (Farthing 2004), because many species of bacteria may develop natural competence, or the ability to take up naked DNA, in the GI tract (Kelly et al. 2009).” (p. 1044)

Both of the papers mention this method. Since then, there is more support for inserting the extra gene is an ideal solution for this problem.


     The further work in this paper is to study the development of gene assessment effect on transgenic cows. The reason is gene assessment can solve both problems from the threat of bacteria and gene deficits. By studying and researching about this topic, pharmaceutical development will have an evolution of natural medicine.

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References:

Bliss, R. (2005). Transgenic Cows Resist Mastitis-Causing Bacteria. USDA/Agricultural Research Service. Retrieved from https://www.ars.usda.gov/news-events/news/research-news/2005/transgenic-cows-resist-mastitis-causing-bacteria/.

Magnus, P. (2008). Transgenic Milk. Veterinary World, 1(10), pp. 319-320. Retrieved from http://www.veterinaryworld.org/2008/October/Transgenic%20milk.pdf.

Potenza, A. (2016). Are These Genetically Engineered Cows The Future of Medicine? The Verge. Retrieved from https://www.theverge.com/2016/12/3/13819482/genetically-engineered-animals-drugs-sab-cows-pharming-future.

TestBiotech. (2017). Genetically Engineered Cows. TestBiotech. Retrieved from https://www.testbiotech.org/en/limits-to-biotech/cow/basic_paper.

Tom Whipple Science Editor. (2017). Genetically Engineered Cows Are Resistant to Tuberculosis. Times [London, England], p. 12. Retrieved from GALE.

Tractor Supply Company. (n.d). Livestock Antibiotics and Vaccines. Tractor Supply Company. Retrieved from https://www.tractorsupply.com/know-how_pets-livestock_cattle_livestock-antibiotics-and-vaccines.

Xu, J., Zhao, J., Wang, J., Zhao, Y., Zhang, L., Chu, M., & Li, N. (2011). Molecular-based Environmental Risk Assessment of Three Varieties of Genetically Engineered Cows. Transgenic Research, 20(5), pp. 1043-1054. Retrieved from ProQuest. doi: 10.1007/s11248-010-9477-3.



     Eurus Thach.