| what are three things scientists dont yet know about stem cells | - how they stop dividing
- how they don’t form neoplasms
- how they find their way to damaged tissue |
| what are neoplasms | abnormal mass – ulcer, lesions, or growth- that is formed when cells grow and divide more than they should |
| define stem cell therapies | Stem cell therapies are treatments for diseases that involve the use of stem cells |
| what are four things stem cells must be able to do before they can be used in treatments | → differentiate into the required tissue
→ they mustn’t be rejected by the immune system (ESCs are less likely to be rejected then ACS)
→ stem cells must be able to replicate themselves in a cultures in a laboratory
→ they must not retain the ability to divide indefinitely |
| what is bone marrow | – fatty soft tissue found in bones
– contains stem cells (haematopoietic stem cells) that give rise to new blood cells |
| what are haematopoietic stem cells | they are stem cells that give rise to new blood cells |
| what are the stem cells found in bone marrow | haematopoietic stem cells |
| what are the two ways haematopoietic stem cells can be derived | can either be derived from...
- bone marrow
- they can be collected from the donor’s blood (stem cells are filtered out of the blood and the rest of the blood is returned to the donor) |
| why are bone marry transplants helpful | they can replace damaged blood cells or disease bone marrow |
| what are some examples of disorders that could be treated with a bone marrow transplant | → cancer – chemotherapy and radiotherapy can damage the stem cells in bone marrow
→ leukemia is a disease that effects the blood cells and patients may have disease stem cells
→ some disorders like aplastic anaemia can be caused by defective DNA or toxins that damage blood cells |
| what is another source of blood stem cells (haematopoietic stem cells) | Blood stem cells can be derived from cord blood (blood from the umbilical cord) – contains “adult” stem cells |
| what are cord blood stem cells | they are "adult" stem cells that can give rise to cells in the immune system and blood cells |
| what are some advantages of using stem cells derived from cord blood | → healthier and younger than adult stem cells
→ if it is collected it can be kept and if the donor needs a transplant later in life the cord blood stem cells would avoid rejection |
| what is one correct disorder being treated with cord blood stem cells | being used to treat type 1 diabetes – provides patients with new insulin producing cells |
| what are intestinal stem cells | they are adult stem cells derived from the epithelial layer that covers the intestine – can repair itself quickly |
| when was the first viable intestinal stem cell collected | 2013 |
| where can epidermal stem cells be found | skin |
| what stem cells does skin have | epidermal stem cells – can divide very quickly |
| how can epidermal stem cells treat burn patients | epidermal stem cells placed onto fibrin gel can grow until they form a layer of skin – can be used to replace the skin damaged by burns
→ can also be used to treat genetic skin condition |
| where are embryonic stem cells derived from | embryos that are 5-7 days old
- usually derived from people who have attended invitro fertilisation – they donate their eggs after they have completed the program |
| what happens to embryonic stem cells after they are collected | they are then cultured under idea condition so they can divide rapidly |
| what are some potential uses for embryonic stem cells | they are pluripotent and can divide indefinitely so they can be used to treat many disorders, including degenerative neurological diseases - Parkinson's disease and Alzheimer's disease
- scientists could also potentially grow whole organs |
| what are some characteristics of embryonic stem cells | they are pluripotent and can divide indefinitely |
| what are some downsides of embryonic stem cells | they have limited uses at the moment as scientists are still finding out how to stimulate stem cells, so they grow into the required type of cell |
| what are induced pluripotent stem cells | adult cells that have been genetically engineered to acquire qualities such as becoming pluripotent and the ability to divide indefinitely (like embryonic stem cells) |
| are there any differences between embryonic and induced pluripotent stem cells | they are derived differently, however it is unknown wether their is any clinical difference between the two |
| what are some potential uses of induced pluripotent stem cells | can be used to treat injuries and grow organs – they are pluripotent so they can replace any type of cell
→ in 2015 scientists grew mini beating hearts (hollow pulsating chambers) from these cells |
| what are tumours | a swelling of a part of the body, generally without inflammation, caused by an abnormal growth of tissue
- they can be benign or malignant |
| what are teratomas | they are a rare type of tumor that can contain fully developed tissues and organs, including hair, teeth, muscle, and bone
-> they grow from stem cells |
| what are some downsides of embryonic stem cells | → not yet possible to stimulate an ESC to differentiate into a certain cell type
→ are difficult to obtain due to ethical concerns
→ can form teratomas or tumours |
| what are adult stem cells | they are rare, undifferentiated cells found in some adult tissues, and are usually only multipotent or unipotent |
| what are some characteristics of adult stem cells | they are multipoint or unipotent
they cant divide indefinitely |
| what does it mean for a stem cell to be immortalised | an immortalised stem cell has been genetically engineered to be able to divide indefinitely
-> any stem cell can be immortalised |
| what is one advantage and two disadvantages of adult stem cells | → advantage - already programmed to differentiate into certain cell so can be used for specific treatments
→ disadvantage - they are also hard to obtain
→ disadvantage - can become tumorous |
