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Discussion And Reply On This Topic

I’m working on a biology discussion question and need a sample draft to help me understand better.

I need you to write a discussion and then. reply for these two posts. For the discussion I need at least 500 min word and for the reply t least 350 words.

After watching the presentation on tissue engineering/regenerative medicine, research and submit either (A) another type of tissue that has been regenerated (one not discussed in the presentation), or (B) an advance in some aspect of this field (a new type of bio-scaffold, a new method for seeding cells, etc.). Include how this therapy compares to the regenerative power of the Holy Spirit in an individual’s life (II Corinthians 5:17).

First post:

Lungs Overview

According to the World Health Organization (WHO), lung diseases are the third leading cause of death worldwide (WHO, 2020). Many common lung disorders are characterized as progressive and irreversible. Three common lung disorders that have no current cure are chronic obstructive pulmonary disease (COPD), bronchiectasis, and pulmonary fibrosis. COPD can occur in two forms emphysema and chronic bronchitis (Wang et al. 2018). In emphysema, the alveoli of the lungs are permanently damaged resulting in loss of surface area which reduces gas exchange. In cases of chronic bronchitis and bronchiectasis, the bronchi of the lungs become permanently enlarged due to recurring inflammation. Pulmonary fibrosis is another irreversible lung disorder caused by scarred or damaged lungs. These disorders all have two things in common there is no cure and they are permanent. While these disorders would lead most to believe lung tissue is very susceptible to injury and has limited capacity to repair itself research conducted in 2018 argues otherwise (Leach et al. 2018). The lungs utilize facultative regeneration for self-renewal. Facultative regeneration is the process by which tissue is repaired when fully differential cells are allowed to re-enter the cell cycle (Tebyanian 2019). Once the cells re-enter the cell cycle they can proliferate and differentiate; this mechanism is helpful but limited in its capacity to resolve recurring problems, or damage to large segments of the lungs caused by disorders such as the three listed above. In many of the disorders previously listed (depending on the severity), a lung transplant might be the only treatment option for the patient. However, lung transplants have their own set of complications for the patient such as affordability, shortages, the viability of the organ, and if the body will reject the foreign organ. Tissue engineering has become a promising idea to combat the growing need for lung treatments (Kotton et al. 2014).

Tissue Engineering

Tissue engineering of the lungs has risen in popularity among researchers, with many developments improving decellularization and recellularization of lung scaffolds. As of 2020 all attempts at transplantation in mice models have led to rapid organ failure (Tsuchiya et al. 2020). The main problem with current lung tissue engineering is that the vasculature of the organ results in significant blood clot formation and eventual organ failure. The immature pulmonary vasculature has been difficult to reconstruct due to the required characteristics such as being easily expandable and having high compliance to accommodate the lungs. Various Japanese institution researchers have attempted to address the problem by reconstructing the mature vasculature of the lungs. The researchers first identified the biomaterial of the vascular niche such as pericytes, ECM, and endothelial cells. The researchers then recreated the vascular niche of the organ focusing on microvasculature for the scaffold. The purpose of the research design was to determine if lung transplantation would be successful if the lung’s microvasculature is engineered. The researchers determined that other issues arise such as capillary leaks and further testing must be conducted (Tsuchiya et al. 2020). While this leaves lung tissue engineering still in development engineering parts of the organ in 10 years is an incredible feat.


Kotton, D. N., & Morrisey, E. E. (2014). Lung regeneration: mechanisms, applications and emerging stem cell populations. Nature medicine, 20(8), 822–832. https://doi.org/10.1038/nm.3642

Leach, J. P., & Morrisey, E. E. (2018). Repairing the lungs one breath at a time: How dedicated or facultative are you?. Genes & development, 32(23-24), 1461–1

471. https://doi.org/10.1101/gad.319418.118

Tebyanian, H., Karami, A., Nourani, M. R., Motavallian, E., Barkhordari, A., Yazdanian, M., &

Seifalian, A. (2019). Lung tissue engineering: An update. Journal of cellular physiology,

234(11), 19256–19270. https://doi.org/10.1002/jcp.28558

The World Health Organization. The top 10 causes of death. (n.d.). Retrieved April 06, 2021,

from https://www.who.int/news-room/fact-sheets/detail/t…

Tsuchiya, T., Obata, T., Hatachi, G., & Nagayasu, T. (2020). Lung microvascular niche, repair,

Second Post:

and engineering. Frontiers in bioengineering and biotechnology, 8, 105.

Wang, S., Wu, J., & Liu, G. H. (2018). First stem cell transplantation to regenerate human lung.

Protein & cell, 9(3), 244–245. https://doi.org/10.1007/s13238-017-0498-z

Second post

ACL Bioengineering


The bioengineered tissue that I’ve chosen to discuss is the anterior cruciate ligament (ACL.) This topic is of interest to me as a girls soccer coach, as ACL ruptures are common among female athletes. The ACL is a vital ligament that prevents the tibia’s anterior translation on the femur during motion in the sagittal plane. An athlete may rupture their ACL when changing directions quickly, which puts the ACL under too much stress.

After an ACL rupture, it is not as simple as suturing the two halves back together—doing so would result in an unstable knee joint. For young athletes, this is not an option. An ACL graft is required to achieve consistent stability and strength. Typically, surgeons opt to graft tendon tissue from the biceps femoris, semimembranosus, semitendinosus (all hamstring muscles,) or the patellar tendon, which is responsible for allowing contraction of the rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius (all quad muscles). Another option for ACL grafts would be an allograft, which would likely involve the use of a cadaver ACL.

The downfall of using a hamstring or quad tendon is that it causes the weakening of that muscle group during the healing phase. This changes the strength ratio between the two muscle groups– one of the leading causes of ACL graft failure. (Kyritsis, et. Al., 2016)

The downfall of using a cadaver graft is that there is a significant change of rejection. Scientists estimate that about 24% of ACL cadaver grafts fail due to rejection, and this is embodied through pain, stiffness, and significantly prolonged healing. (American Orthopaedic Society for Sports Medicine, 2008)

One benefit of using a bioengineered ACL is that it does not create any muscular strength imbalance between the two muscle groups– hamstrings and quads– which leads to a reduced chance of post-operative graft rupture. Additionally, a bioengineered ACL comes from the patient’s own cells, meaning there is little to no chance of the body rejecting the graft. Both benefits could lead to improved patient outcomes, specifically in young athletes who may put their ACL graft under greater-than-average stress during their sport. (Marzotto, et. Al., 2017)

Currently, bioengineered ACL grafts are not used on patients but have shown great success in porcine models. Scientists attached a scaffold and multipotential stromal cells to the original attachment site of the ACL on the femur or tibia, and the other side of the scaffold was attached to the remaining bit of the ACL ligament. The cells grew inside the porcine models to form a fully functional ACL ligament. (Marzotto, et. Al., 2017)

Scientists noted no failure; however, rejection is typically assessed by subjective reports such as pain and stiffness. A porcine model, unable to speak, may or may not have had these symptoms, and rejection was therefore not identifiable unless apparent tissue death or malformation could be observed upon dissection. (Marzotto, et. Al., 2017)

Tissue regeneration through bioengineering compares to the Holy Spirit’s regenerative powers because when someone who has not yet been shown the way of the Lord is exposed to his greatness and power, it creates a burst of life in said person. They may even have an entirely new outlook on life because of the understanding of God’s greatness and love. As tissue regeneration positively improves an affected individual’s life, so does the generation of understanding and admiration of the Lord.


American Orthopaedic Society for Sports Medicine. (2008). Cadaver tissue fails nearly 25 percent of the time in young ACL reconstructions. https://www.sciencedaily.com/releases/2008/07/080710070813.htm

Kyritsis, P., Bahr, R., Landreau, P., Miladi, R., & Witvrouw, E. (2016). Likelihood of ACL graft rupture: Not meeting six clinical discharge criteria before return to sport is associated with a four times greater risk of rupture. British Journal of Sports Medicine, 50(15), 946-951. https://10.1136/bjsports-2015-095908

Marzotto, T., & Alt, P. M. (2017). Stem cell research (1st ed.). Routledge. https://10.1201/9781315152943

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