Naked Science Forum

Life Sciences => Physiology & Medicine => Topic started by: Johan on 26/07/2008 15:06:44

Title: When will stem cell operations become a practical reality?
Post by: Johan on 26/07/2008 15:06:44
Johan asked the Naked Scientists:

Dear Chris

When will stem-cell operations will become a practical reality?

Thanks

Johan

What do you think?
Title: Re: When will stem cell operations become a practical reality?
Post by: chris on 28/07/2008 15:54:03
Hi Johan

they already are! There are hundreds of people alive today thanks for stem cell transplants. This might sound surprising, but doctors have been doing this for many years, mostly in the form of bone marrow stem cell transplants for patients with leukaemias.

The way this is achieved is to find a donor who is a close genetic match for the patient. Usually this is a first degree relative (sibling, parent and so on).

Bone marrow stem cells are collected from the donor either by bone marrow tap (drilling a hole into the marrow cavity and sucking the stem cells out), or less painfully by giving a drug called G-CSF, which causes the stem cells to increase their rate of cell division so that they begin to spill out into the blood stream; this means that they can be harvested from peripheral blood.

The harvested cells are then stored while the patient undergoes ablative therapy - radiation and cytotoxic drugs - to remove their own diseased bone marrow. Once these toxic drugs have been flushed from the patient and their own bone marrow has been destroyed the donor stem cells are re-infused via a vein; they then home back to the bone marrow where they take up residence and begin to multiply, replacing the patient's own missing marrow.

The technique is hugely successful and has saved many lives.

Chris
Title: When will stem cell operations become a practical reality?
Post by: Karen W. on 29/07/2008 01:41:12
I understand there are good results such far for heart treatment from these same stem cells.. Have they become better since 2005? as far as stem cell therapy for heart patients... and where would one go to have their own stem cells harvested and saved for self treatment down the road or now?
Title: When will stem cell operations become a practical reality?
Post by: GBSB on 29/07/2008 01:47:08
This might sound surprising, but doctors have been doing this for many years, mostly in the form of bone marrow stem cell transplants for patients with leukaemias.

I know that a few years doctors transplanting the bone marrow tissue but I didn’t hear that someone has separated bone marrow stem cells from the bone marrow tissues.
Maybe my information’s are outdated. Can you post some links that explain more about bone marrow stem cells transplants?

The technique is hugely successful and has saved many lives.

I didn’t hear too much about successes of this technique. Can you post some links that tell more about that?
Title: When will stem cell operations become a practical reality?
Post by: Karen W. on 29/07/2008 01:55:49
Yes the ones I read were from 2005....I also would be very interested as I heard in Korea or India, Egypt, or somewhere they have had much success with those cells in healing the heart and even growing new hearts and doing those transplants!
Title: When will stem cell operations become a practical reality?
Post by: JnA on 29/07/2008 05:32:13
"or less painfully by giving a drug called G-CSF, which causes the stem cells to increase their rate of cell division so that they begin to spill out into the blood stream; this means that they can be harvested from peripheral blood."


that is very cool.

Title: When will stem cell operations become a practical reality?
Post by: Karen W. on 29/07/2008 05:45:00
That really appeals to me as I have heard that retrieving or removing bone marrow has been very painful in the past so this way of retrieving seems so much more humane and comfortable....

Brings me to another question for another thread!
Title: When will stem cell operations become a practical reality?
Post by: chris on 29/07/2008 09:23:05
I didn’t hear too much about successes of this technique. Can you post some links that tell more about that?

It's actually a pretty standard technique these days. The process of supporting patients through an "allogeneic" (non-self) bone marrow graft is not easy, but it is very successful and there are very good protocols now used worldwide to treat patients with a range of haematological diseases, including non-cancer problems like aplastic anaemia (bone marrow failure).

I don't think he'll mind me saying that someone who taught me geography when I was 8 years old and with whom I have remained in close contact since, developed CML - chronic myeloid leukaemia about 16 years ago. His disease transformed into an aggressive form and he needed bone marrow transplantation. In his case stem cells were donated by his brother. Subsequently he is alive and well, and disease free, all these years later. Long may it continue.

Chris
Title: When will stem cell operations become a practical reality?
Post by: Karen W. on 30/07/2008 05:37:24
That is really incredible Chris! Thanks for telling us that!
Title: When will stem cell operations become a practical reality?
Post by: that mad man on 30/07/2008 18:27:56
I can testify on the effectiveness of using the drug called G-CSF.

My brother suffered from bone cancer and needed a bone marrow transplant a while ago. He had 2 sibling donors with a close match, myself and my sister but because I have a simple virus CMV I couldn't donate. Luckily for him my sister was fine.

She had a course of the drug and blood was taken from her over a period of 24 hours which was then filtered to remove the excess stem cells and the rest was given back to her. She said the only effect she had was to feel light headed and had to stay in Hospital while they were extracting the cells.

After several courses of chemotherapy my brother was then given those extracted cells. After several months my sister underwent the same treatment and my brother was given them as a "top-up".

His white blood cell count is almost normal, not 100% but he is now well enough to be back at work. He still has to be careful with infections and has recently had a lung infection but antibiotics worked fine for him.

The old fashioned way of extracting them direct from the spongy part of the hip (normally) is rarely used.
Title: When will stem cell operations become a practical reality?
Post by: Karen W. on 30/07/2008 22:47:56
That is amazing MM. Many good wishes to your broyher.

 I am amazed how they can separate the stem cells from the blood... really amazing! Sounds like a much better way to go..

Please tell me from your brothers point of view is the procedure as easy on him in reverse when he is given the stem cells or are they put in differently into his bones or is it blood transfusion...???
Title: When will stem cell operations become a practical reality?
Post by: that mad man on 31/07/2008 01:20:54
Hi Karen.

In my brothers case it was transfused via a drip over a few hours and I believe it was into a vein in his arm. I will have a word with him as I'm not too sure how much in millilitres/litres he was given. I seem to remember my sister saying it was quite a lot but it always looks a lot when in those bags!

I have just found the information pack which was given to me by the Hospital so here is a bit more information but this was for me.

Mobilisation.
Stem cells are mobilised using GCFC; this is given as a subcutaneous injection twice daily for four days prior to harvesting. You may experience minor discomfort at the injection site. By the third or fourth day of injections you may experience aches in bones and muscles.

Risks.
GCFC also elevates the total white cell count in the blood, which can raise 6-8 fold. Side effects are few but can include; tiredness, mild bruising from cannulas and some effect from the anticoagulant sodium citrate that causes symptomatic low calcium levels.

On the fifth day, you will receive an injection in the morning and then attend our stem cell harvesting suite. Two wide bore cannulas will be inserted, one in each arm at the elbow into a large vein. Blood will then be circulated from one arm through the harvesting device, where the stem cells will be separated from other blood components such as platelets, red cells and plasma. The remaining blood will then be returned via the other arm. If insufficient stem cells were collected on one visit then a further dose of GCFC will be required in the evening and the following morning followed by another harvesting session. An assay will be taken to ensure sufficient stem cells have been collected. If this does not work then a bone marrow harvest will be requested.

Cell storage
Most donated cells are often used shortly after storage but they may be kept for use later. Once frozen they may be kept in storage for many years. The minimum storage period is usually 5 years after which the storage will be reviewed. Stored cells will not be disposed of without your permission.

Surprisingly I didn't realise until reading this that its not a complete cure but designed to prolong survival for several years.

I will be speaking to him on Sunday so I will find out more and will be happy to post back.
Title: When will stem cell operations become a practical reality?
Post by: Karen W. on 31/07/2008 02:29:22
Thanks MM it is all very enlightening! I would appreciate that info too.