Cell based biologics

Question 1

What do we mean by cell therapy? Where can we get them from?

Answer 1

The clinical use of cells to replace or repair damaged or defective tissues of the body.

• Cells can be removed from one part of the body and used elsewhere in the body
• Cells can be removed from a donor source
• Cells can be expanded in vitro (ex vivo)

Question 2

What does ATMP stand for?

What are some examples of them?

Answer 2

advanced therapy medicinal products

• gene therapy medicinal products
• somatic therapy medicinal product
• tissue engineered products

Question 3

A tissue engineered product means a product that:

Answer 3

• contains or consists of engineered cells or tissues, and
• is presented of having properties for human administration in order to repair or replace a human tissue
• a tissue engineered product may contain cells or tissues from human origin, animal origin, or both.
• Cells may be viable or non-viable. They may also contain additional substances such as cellular products, biomolecules, biomaterials, chemical substances, scaffolds or matrices.

Question 4

There are three sources for somatic cell therapy. (all cells are living cells). What do these three sources mean?:

• autologous
• allogenic
• xenogenic

Answer 4

• from the patient themselves
• from another human being
• from an animal

Question 5

What is reconstruction?

Answer 5

The ability to rebuild missing tissues/ organs e.g grafting/ tissue engineering

Question 6

What is regeneration?

Answer 6

The ability to create an environment to allow the body to rebuild itself e.g. cells, growth factors, supply of templates

Question 7

Name some soft tissues

Answer 7

Heart
Skin
Cornea 
Pancreas
Blood vessels
Neuronal tissue

Question 8

Name some hard tissues

Answer 8

Bone

Cartilage

Question 9

• Stem cells are not themselves _______ differentiated.
• When they divide, each daughter cell has a choice:
• They can divide without _____; they usually express an enzyme ______ that prevents _______ ________. Therefore they do not ______ (stop dividing)

Answer 9

• terminally
• either remain as a stem cell or embark on a course that commits to terminal differentiation
• limit
• telomerase
• telomere shortening
• senesce

Question 10

The ______ the stem cell potency, the more cell types it can give rise to and the _____ differentiation the cell is considered to be

Answer 10

higher

less

Question 11

single cell embryo = ________ stem cell

Answer 11

totipotent

Question 12

5-7 day embryo = _______ stem cells

Answer 12

pluripotent

Question 13

Adult stem cells = ________ stem cells

Answer 13

multipotent

Question 14

Early development (embryogenesis) is characterised by the rapid

Answer 14

proliferation of embryonic cells, which then differentiate to form the specialised cells of adult tissues and organs

Question 15

In general, there are epithelial tissues deriving from all of the embryological germ lines. These are:

Answer 15

• ectoderm (e.g. epidermis)
• endoderm (e.g lining of GI tract)
• mesoderm (e.g inner linings of blood cavities)

Question 16

Where are some places where adult stem cells are found?

Answer 16

• bone marrow stromal cells (mesenchymal)
• haemotopoietic stem cells
• epidermal skin cells
• gut epithelial stem cells
• neural steam (–> go on to form neurones, astrocytes etc)

Question 17

READ AND TRY REMEMBER

Answer 17

• Intestinal epithelial stem cells replace the intestinal epithelium every few days.
• They migrate upwards from the crypt of the bowel lining.
• They have limited potency i.e. they are destined to become absorptive epithelial cells, goblet cells or microendocrine cells.

Question 18

Ethics, Legal and Social issues:

• Current UK legislation allows the use of spare embryos from fertility clinics to be used in stem cell research until _____ after creation
• It is ___ currently permissible to create new embryos purely for research purposes
• Therapeutic cloning (i.e. the fusion of an adult somatic and an egg cell) to create ES cells ____ permissible

Answer 18

• 14 days
• not
• is

Question 19

Skin epithelial stem cells are_____ stem cells, basally located, slow cycling cells with ____ proliferative potential

Answer 19

unipotent

high

Question 20

What region of the cornea contains a reservoir of slow cycling, corneal epithelial ‘stem’-cells

Answer 20

Limbal

Question 21

READ THIS SUMMARY

Answer 21

• Both embryonic and adult stem cells have potential uses for cell therapy and tissue engineering.
• Adult stem cells are difficult to isolate and have limited potency.
• Embryonic stem cells can potentially be differentiated into any cell type, however establishing the growth factor regime required to do that is difficult and there are legal and ethical implications.
• Applications range from the use of cells for tissue regeneration (e.g. skin, corneal, neuronal, hepatic, cardiac etc) to the engineering of whole organs in the laboratory.