Organ Transplantation, Regenerative Medicine & Tissue Engineering – Review Flashcards

This set of 65 question-and-answer flashcards covers organ transplantation logistics, regenerative-medicine principles, extracellular-matrix biology, embryo-research limits, 3-D printing, mRNA therapeutics, and related ethical considerations.

What is the typical average wait-time for patients on an organ-transplant list?

About 3–5 years.

The heart is the _ most needed solid organ for transplantation in the United States.

Second.

What is regenerative medicine?

A field focused on repairing, replacing or engineering cells, tissues, and organs to restore normal function.

Which animal’s tissue is most commonly used to build an experimental bio-engineered heart?

Pig tissue.

Name one of the principal fibrous proteins found in the extracellular matrix (ECM).

Collagen.

When constructing a new heart, what is the very first laboratory step?

Wash the donor heart with detergent to decellularize it and leave a protein scaffold.

For how many days may synthetic or in-vitro embryos legally be grown in most countries?

14 days.

3-D printing can be used to create which of the following? (objects, cells/tissues, food)

All of the above.

An acceptable cadaver source for a bone graft is a _.

Human donor (cadaver).

Legal death for organ donation is officially determined by absence of _ .

Brain function (brain death).

After life support is withdrawn, a liver must be retrieved within _ minutes for a successful transplant.

30 minutes.

Which factor is NEVER considered by UNOS when allocating donor organs?

The potential recipient’s income status.

Name the eye disease that affects ~8 million Americans and is linked to loss of retinal pigmented epithelial cells.

Age-related macular degeneration (AMD).

After decellularization, which structural molecule is left behind in the heart scaffold?

Collagen.

Why do researchers place a decellularized heart into a bioreactor?

To mimic mechanical/electrical beating and provide nutrients so new cells can repopulate the scaffold.

At what developmental day does the human embryo first display the primitive streak?

Day 14.

Groups of cells secrete their own support structure called the _.

Extracellular matrix (ECM).

Which description does NOT apply to therapeutic mRNA?

Infectious.

List four of the most common medical uses for 3-D printing.

Medical equipment/devices, anatomical models, implants and prosthetics.

Which manufacturing approach does NOT require the costly tooling of conventional methods?

3-D printing.

Within how many minutes should kidneys ideally be retrieved after circulatory death?

≈ 30 minutes.

The emerging field that replaces malfunctioning cells with newly produced ones is called _.

Regenerative medicine.

Stem-cell-derived human brain cells are currently used primarily for _.

Drug testing and disease modeling (e.g., Parkinson’s research).

Name two cell types commonly used during heart recellularization to line vessels and seed chambers.

Endothelial precursor cells and cardiac muscle cells.

Federal guidelines allow human embryos in the lab to develop for no more than _.

14 days.

Which type of RNA is most stable and resistant to RNase degradation?

rRNA.

A 3-D printer fabricates an object by reading a _ and reproducing it layer by layer.

Digital blueprint (CAD file).

Stem cells that can become ANY cell type in the body are called _.

Pluripotent cells.

Which carrier system is widely used to protect therapeutic mRNA in vivo?

Lipid nanoparticles.

The detergent perfusion step during decellularization primarily _ .

Strips DNA and other cellular material from the tissue.

According to public campaigns, what is often called the “ultimate act of human kindness”?

Organ donation.

About how many people die each day in the United States while waiting for an organ?

Approximately 17 people.

Name three solid organs that can sometimes be donated by a living person.

One kidney, part of a liver, and a lobe of lung.

What is considered a crucial driving force behind regenerative medicine advances?

Stem cells.

The extracellular matrix is primarily composed of which two macromolecule classes?

Proteoglycans and fibrous proteins.

Collagen in the ECM associates closely with which adhesive glycoprotein?

Fibronectin.

A decellularized scaffold heart does NOT need to be _ to function as a template.

Alive or beating.

Who argued that time-based rules don’t apply to embryos not formed by fertilization?

Dr. George Church & Dr. Alexander Aach (often cited simply as Dr. Aach).

Which university first kept fertilized human eggs alive for two days in a dish (1940s milestone)?

University of Cambridge.

Which animal tissue offers a safer, virtually unlimited scaffold supply compared with human tissue?

Pig tissue.

After the heart stops in donation after circulatory death, clinicians must wait _ before declaring death.

Five minutes without a heartbeat.

The majority of deceased organ donations occur after what medical determination?

Brain death.

Why are detergents pumped through a donor heart during organ engineering?

To remove all cellular material, leaving a clean protein scaffold.

Name the two major macromolecules that form the extracellular matrix.

Proteoglycans and fibrous proteins.

Early embryonic cells eventually segregate into three primary _.

Germ layers (ectoderm, mesoderm, endoderm).

PEI-based nanocarriers are being explored mainly for _ applications.

Tissue regeneration and gene delivery.

Typical overall waiting period many patients experience for donated organs is _.

3–5 years.

Name two major complications associated with bone-graft transplantation.

Immune rejection and the possibility of being outgrown by children.

Successful tissue engineering requires which trio of factors?

Appropriate cells, proper growth environment, and necessary biomolecules (growth factors).

What is the primary role of a scaffold in tissue engineering?

Providing a structural framework on which cells can attach, grow and organize.

The acronym “SHEEF” stands for what?

Synthetic Human Entities with Embryo-Like Features.

Under proposed ethical rules, scientists must NOT create a SHEEF that _.

Can feel pain.

One major advantage of mRNA-based therapy over DNA-based therapy is that mRNA is _.

Non-infectious and does not integrate into the host genome.

Biological 3-D printing is best defined as _.

Fabricating 3-D tissues or structures using living cells and biomaterials layer by layer.

Roughly what percentage of Europeans are registered as organ donors?

About 90 %.

Biomaterials used in regenerative medicine can be or .

Natural or synthetic.

During heart construction, the first critical step is to _ the donor heart.

Remove all cells with detergents, leaving only the protein scaffold.

Which item is NOT a component of the extracellular matrix: fibrous proteins, polysaccharides, adhesion proteins, or compact bone?

Compact bone.

Integrins are best described as _.

Transmembrane receptors (α/β subunits) that link cells to the ECM.

In cell signaling, scaffold proteins primarily _ .

Organize and spatially regulate signaling pathways by bringing multiple partners together.

Artificial mouse embryos in the lab were able to self-organize because embryonic stem cells _.

Communicated with each other and arranged themselves without external patterning cues.

The overarching goal of regenerative medicine is to _.

Restore or replace damaged tissues or organs by activating the body’s own repair mechanisms or using engineered substitutes.

One way nanoparticles assist regenerative medicine is by _.

Delivering therapeutic agents (e.g., growth factors, genes) directly to regenerating tissues.

Which two advantages describe 3-D printing for tissue engineering?

It allows customizable scaffolds that mimic natural tissue and can replace damaged tissue or organs.

Define stem cells.

Undifferentiated cells capable of self-renewal and differentiation into specialized cell types.

A suitable regenerative-medicine treatment for a child lacking healthy bone marrow is _.

A stem-cell (bone-marrow) transplant.