lec 6&7

Question 1

When was the first BM transplant?

Answer 1

Cooperstown NY in 1950s. Involved identical twins one of whom had leukaemia.

Question 2

First successful allogeneic BM transplant

Answer 2

was in 1968 at this time it was known that matching of HLA was crucial.

Question 3

First successful BM transplant from unrelated patient

Answer 3

donor was in 1973 when a young boy with immunodeficiency disorder received multiple marrow transplants from a donor in Denmark.

Question 4

Define Cell therapy

Answer 4

Cell therapy can be defined as a therapy in which cellular material is injected into a patient to treat a disease or injury.

Question 5

what are the 2 grades of cells?

Answer 5

Reagent grade - lab use
GMP grade (good manufacturing practices) - for use in humans. It has documented acts of demonstrating procedure, process, activity.

Question 6

what are 2 main principles by which cells facilitate therapeutic action?

Answer 6

1. Directly replace damaged tissue, leading to repair and regen
   Cardiac stem cells after myocardial infarction.
   2. Paracrine effect - release soluble factors which promote repair and regen of the tissue or organ.
      E.g mesenchymal stem cells after myocardial infarction

Question 7

define a medicinal product

Answer 7

A medicinal product would be a product that is directly transferred to the patient without any manipulation. If it is medicinal it does not contain any cells or no longer viable cells.

Question 8

what is ATMP

Answer 8

Advanced therapy medicinal products (ATMPs) are medicines for human use that are based on genes or cells.

Question 9

describe GTMP

Answer 9

1. Gene therapy medicines (GTMP):
   A product containing genes that lead to a therapeutic prophylactic or diagnostic effect. They work by inserting recombinant genes into the body. Can be used to treat genetic disorders, cancer or long-term diseases.

Question 10

Describe sCTMP

Answer 10

2. Somatic cell therapy medicines (sCTMP):
   A product that contains cells or tissues that have been manipulated to change the biological characteristics. But NOT to be used for essential functions in the body.

Question 11

Describe TEP

Answer 11

3. Tissue-engineered medicines (TEP):

Contains cells or tissues that have been modified so they can be used to repair, regenerate and replace human tissue.

Question 12

combined ATMPs

Answer 12

4. Combined ATMPs:

Containing one or more medical devices as an integral part of the medicine.

Question 13

To be an ATMP the product must fit into at least one of these categories??

Answer 13

1. Be substantially manipulated:
   Change in biological, physiological function or structural properties.
   i.e gene mod, cell expansion, differentiation with GF, enzymatic digestion to dissociate cell-cell adhesion.
   
   2. Have a different essential function:
      Used for a different function than they had in their original location.

If it doesnt satisfy the conditions it is a Cell therapy product (CTP)

Question 14

What has CTP been successful with?

Answer 14

BM (blood) and Epithelial tissue (skin).
• This is because they are relatively simple compared to the other stem cells in our body.
• They have a fast turnover
You can ablate the diseased BM/skin and replace with the healthy tissue/cells that have been produced.

Question 15

Epithelial cell therapy by Howard Green

Answer 15

Skin grafts were the first ever TEP to be used (Howard Green)
The human epidermal stem cell keratinocytes were isolated and serially cultured in vivo on a feeder layer of mouse fibroblasts. This was repeated every couple of weeks with a new layer of feeder cells (BM that doesn’t divide).

Question 16

Where was the Howard Green concept used?

Answer 16

This concept was used in burn therapy.
Skin was taken from unaffected region (biopsy)
It was cultured onto a feeder layer
The collagen scaffold (dermal scaffold) was put down (not the cultured cells!!).
The cultured cells were seeded on the scaffold and it proliferated into a good skin.

Question 17

Why isnt autologous cell therapy used?

Answer 17

An autologous cell therapy isn’t rapid enough to treat burns but some companies such as organoenesis make skin constructs from allogeneic skin donations. This can act as a temporary barrier while the host skin grows back. As you can see below the construct is a good barrier but doesn’t have all the cells like normal skin as the primary function of apligraf is to provide a barrier.

Question 18

What area gives rise to the TA cells of the eye?

Answer 18

The limbus gives rise to transit amplifying cells which then differentiate into cornea.

Question 19

pros of culturing limbal stem cells for corneal renewal and repair

Answer 19

The limbal stem cells can be isolated and cultured on fibrin.
This is good as we don’t want contact with animal products. Serum is from cowx so development of serum-free feeder layers is important. Fibrin is not an animal product.

Question 20

What is the stem cell marker for eye? and why is it important

Answer 20

P63
This is important because it shows that the stem cells produced have a self renewing function. In a short time period cell culture we cannot tell from observation which ones are self renewing and which aren’t as in cell cultures of stem cells we get a wide range of cells and not just stem cells being produced.

Question 21

What is first approved ATMP for corneal damage?

Answer 21

Holoclar is the first ATMP to be approved in the EU to treat corneal damage.
It is an ATMP and a TEP due to its MoA.

Question 22

Epidermolysis Bullosa. What is it?

Answer 22

It is caused by mutations in laminin (BM protein)

IF there is no Laminin it is death as soon as birth.

Question 23

How do we treat EB using stem cells?

Answer 23

The first incidence of treatment for this was from compassionate use of combined ex vivo cell and gene therapy.

The skin was taken and the genetic code was modified and then screened
The non-oncogenic cells were then cultured
The resulting cells had a range of reproductive capacity - holoclones, meroclones, paraclones

The holoclones are true stem cells.
H,M,P were put onto the body and after 8 months the holoclones replaced the other cells.