Video

Pig cell transplants treat diabetes

Type 1 diabetes is currently treated with insulin injections, but this is an imperfect process that can have severe health complications. Live cell transplants improve on this treatment because they can respond to blood sugar levels and release appropriate amounts of insulin.

LCT sources live cells from pigs because human cells are in short supply. The advantage of using pig cells is they can be supplied in the amounts needed; the disadvantage is they may be rejected by the patient. LCT encapsulates the cells in a seaweed-based coating to overcome the problem of rejection and to prevent the patient needing immune suppressing drugs.

Questions to consider

  • Why does LCT source their cells from pigs instead of humans?

  • What are the advantages and disadvantages of using pig cells to treat type 1 diabetes

  • How does encapsulation contribute to the effectiveness of this treatment?

Teaching points After watching this clip, find out more about how pig islets cells are encapsulated, in the article Preventing pig cell transplant rejection.

Transcript

Bob Elliott (Living Cell Technologies) What we’re trying to do in LCT is come up with an alternative method of treatment – something very new for diabetes and a number of other diseases – where, instead of giving a drug or some surgery for a medical condition, we’re using live cells to correct the disease process.

Now, this is the problem with standard treatment of diabetes where we give many insulin injections per day, trying rather unsuccessfully to keep the blood glucose levels in the normal range. When we’re using living cells, they respond as the normal pancreas responds, which is putting out insulin when needed and stop making it when it’s not needed. So we get a much more even control of blood glucose by using live cells rather than injecting a drug.

We looked at using human cells, but the only source there would be from organ donors, people who have been killed in road accidents and so on and have been prepared to donate live cells. That would very, very much restrict what we could do, so we switched to using an animal that has some close similarities with humans – that is the pig. We’ve lived with pigs for millennia now and we know about their diseases, and that was important because we had to make sure that the pigs we were going to use as a source of these cells were free of any disease that could be transmitted to man.

The problem there is pig cells would normally be rejected almost immediately when you put them in the body so we had to come up with a strategy to protect these cells from being rejected. And the one we chose was to coat them with a semi-permeable membrane in what we call a capsule but it’s actually a coating of the insulin-producing cells, which allows the insulin out and allows nutrients and oxygen in but protects the cells from being seen by the immune system, which is the one that normally rejects any foreign cells rather rapidly. So this was the strategy using animal cells rather than human cells and encasing them in a semi-permeable coating which prevented them from being rejected after they’re injected into the body.

Acknowledgements Michael Helyer PRN Films

Rights: University of Waikato
Published:09 November 2011