Now that you've learned about the process of xero transplantation during part one of this video
series on the first pig to human heart transplant we're going to dive into more detail on the actual
surgical procedure and the implications it has for the medical world in this video
understanding the first pig to human transplant beyond the headlines
imagine a world where once severe life-threatening conditions could be diminished
replaced by survivable conditions that do not limit the lives of ill individuals
through the power of transplantations this vision could become a reality discuss in part 1
risks such as rejection and the resulting infections can restrict the feasibility of
transplants in the medical world however the major factor contributing to limited organ transplants
is a lack of organ availability lack of human donor stems from reluctance by donors or their
families along with the difficulty of obtaining viable organs from deceased patients this has
led to an average waiting time of three to five years for organ transplants and unfortunately it's
estimated that 22 people a day will die waiting for organ donors these alarming statistics drove
dr griffith and dr mojito along with their team at the university of maryland to attempt the first
pig to human heart transplant but how exactly were they able to pull off this revolutionary surgery
griffith and mohit along with their colleagues found the best strategy to minimize the risk
of rejection during the peak to human heart transplant was to genetically modify the pig heart
to be as closely replicated as the human heart as possible and this was achieved through modifying
the pig's dna dna is known as the blueprint of life as it provides cells with the information
needed to function and display traits that make each individual unique genes are the various
sections of dna that control different functions and characteristics of human cells everything from
eye color to heart function is influenced by the genes we possess although each individual's dna
is unique there are significant similarities in genes for those part of the same species
therefore in order to close the gap between the differences between a pig and human heart
griffith and mojit found that altering the dna the pig heart to eliminate genes to distinct for pigs
and include human genes related to heart function to reduce the chance of rejection and they were
able to do this using a gene editing technology called crispr cast9 crispr cassoun allows us to
make cuts in the human gene dna at sites that contain genes that we want to eliminate so the
human body has natural cellular repair mechanisms to respond to any damage in the dna so when the
cell sense that these cuts have been made in the dna it uses this repair mechanism to correct
it normally the cell will simply repair the dna by adding back the genes that have been removed
however in crispr cast 9 scientists will actually add templates for new genes so the cell will
instead repair the dna by incorporating these new desired genes in it and now we have altered the
human dna more details on this biotechnology will be provided in part three of this video series
grid to the emojis use the crispr9 technology to remove three genes responsible for creating sugars
found in pigs but not humans as the production of these sugars in the human body but likely
triggered immune response since their foreign to the human recipient a growth hormone gene was
also knocked out from the pig heart to ensure the heart maintained a normal human size and lastly
six genes involved in controlling inflammation and humans was added to the pig heart to allow
it to mimic the human immune response now that we understand how researchers were able to construct
a pig heart into a suitable donor for a human let's examine the recipient in this procedure
david bennett a 57 year old man suffered from severe irregular heartbeats and his condition
was critical as he relied on a heart lung machine for months now to have normal heart function
due to a history of not complying to doctor's instructions bennett was ineligible to receive a
human heart donor transplant and the nature of his irregular heartbeats made an artificial heart pump
out of the question for him which led to his decision to give consent to be the human recipient
for the first pig to human heart transplant on january 7th 2022 dr griffith and dr mohian removed
the pig heart from the adult donor pig after altering its genes during its embryonic growth
the heart was stored in a box engineered to keep it vital until it was transplanted into bennett's
body that same day it's now been over two months since the surgery and ben is still in the recovery
stage at the university of maryland's hospital early on in his recovery he did experience an
abdominal infection due to the use of strong immunosuppressants to limit an immune attack
on the new heart however he later recovered from this infection also during his recovery
it was found that bennett's new heart was beating with excessive force and speed
which led to a prescription of medication to help relax its activity as of now this peak to human
transplant is viewed as a success however the full extent of its results will not be fully understood
until we learn more about bennett's condition in the future so what does this surgical discovery
mean for the medical world the pending success of venice procedure opens the door to the
possibility of using xenotransplantations as a medical treatment for a whole range
of diseases researchers have already discussed the possibility of genetically modifying animal
organs specific for the genes of each human recipient to minimize the chance of rejection
therefore each human recipient would receive organs genetically modified to best specifically
fit their unique genes however at this time xenotransplantation is still an experimental
procedure and only with time and future research can we fully uncover the possible harms associated
with these types of procedures and the lasting impacts they could have on our society thank you
to learn more about the biotechnology behind this
procedure please proceed to part 3 of this video series