Life span of a transplanted pig cell

LCT first transplanted pig cells into a male patient with type 1 diabetes in 1996. 10 years later, the patient was still reporting better control of his blood sugar. Bob Elliott and the team at LCT took samples from the patient’s abdomen and found some live pig cells that were still producing insulin.

Transcript

Bob Elliott (Living Cell Technologies) We’re not sure yet exactly how long these pig cells will continue to work in people. We know they don’t start to work until 8–12 weeks after the transplant – they’re quite immature islets because we’re using newborn piglets as the source – and 8–12 weeks after the transplant, we see a drop in insulin dose pretty regularly. Then that seems to wear off for a while.

But the effects we see may last a very long time. In the New Zealand trial, for instance, the number one patient, he’s still free of this unaware hypoglycaemia 2 years after a single injection. Way back in 1996 when we first started with a primitive prototype, we put in a million cells into a 45-year-old type 1 diabetic, and we saw something of the same pattern. His insulin dose dropped in the first few months and then went back to normal, and I thought it was all over. But he kept saying, “No, you’re wrong, I’m having much fewer low blood glucose turns, I don’t go as high as I used to,” and eventually we had a bet on. And I said, “Well, I think you’re just imagining these things,” and he said, “No, I think you’re wrong.”

So we looked inside his belly again and, sure enough, he was right. There were still some live pig cells, encapsulated pig cells there. We could scrape some off and have a look at them, they were still making a bit of insulin and, yes, he was right. That they had lasted for 10 years producing some insulin, not much, not enough to make anything I could measure, but he was right, he wasn’t going as high and he wasn’t going as low. He’s now 14 years after his injection, he still says the same thing, and I think he’s right that there is long-term survival of at least some of the cells that we transplanted. How many? Probably not many, but some – enough to make a difference as far as he’s concerned.

Acknowledgements PRN Films Michael Helyer