Norman Swan: One of the most feared complications in a premature baby is bronchial pulmonary dysplasia. Bronchial pulmonary dysplasia, BPD, is commonest in the smallest babies and is linked to the baby having to be ventilated and in general needing a lot of life support in the neonatal intensive care unit. Babies with BPD don't get enough oxygen into the bloodstream easily, are at higher risk of dying and a host of other complications including cerebral palsy. And when the baby goes home they often need oxygen for months.

But there may be an answer thanks to world first research at the Hudson Institute at Monash University where they've just completed a ground-breaking trial of stem cells. In fact the paper was published today. Rebecca Lim is the lead scientist and is in our Melbourne studio. Welcome Rebecca.

Rebecca Lim: Hello Norman, thank you for having me.

Norman Swan: Why should stem cells help bronchial pulmonary dysplasia?

Rebecca Lim: Possibly not stem cells as a broader sense of the word, but what we think is happening is really the placenta with the amniotic sac that surrounds the baby during the course of pregnancy, we know that the human amnion has had for well over a century now amazing wound healing effects.

Norman Swan: Really? Give me an example.

Rebecca Lim: Yes, so in 1910 it was a paper that I found trolling through…do you remember what a library is?

Norman Swan: No, it sounds familiar.

Rebecca Lim: So I remember presenting this to a group of medical students because they…

Norman Swan: Who had never heard of a library before.

Rebecca Lim: Who have never been in the university library I don't think. So I did a little scan of this article that I found and it was from 1910, so the use of the human amnion as a biological bandage. And then if you fast-forward 100 years there are still randomised controlled trial data out there showing that the human amnion is actually far superior to traditional bandages when it comes to wound care for third degree burns and for skin grafts.

Norman Swan: So what's in it, what's in the membrane?

Rebecca Lim: Well, if you think about the human pregnancy, it has got to actually adapt the maternal immune system to the foetus in order to have a healthy pregnancy that lasts the length that it's meant to. So a lot of immunological changes happen, and a lot of those effects are actually associated with wound healing, and if you link that to the clinical trial data that's out there around wound care. So when the baby's lungs are stunted as a result of the steroids that they are given and when they are given supplemental oxygen and ventilated, their blood vessels in the lungs actually slow down. So the process of angiogenesis slows down…

Norman Swan: So that's the production of new blood vessels and the growth thereof.

Rebecca Lim: Yes. And in the development of lungs in babies, that process, along with the development of new air sacs, so alveolarisation, so those two processes actually go hand in hand. So when you have the stunting of those two processes in the babies and you give them placental derived stem cells, these amniotic cells, what it does is actually kick-start that process all over again. So new blood vessels start to form, the endogenous…the stem cells that are already present in the baby's lungs, they get kick-started as well, and both of those processes end up overcoming that stunting effect.

Norman Swan: So it's like a generalised effect, an internal bandage that is active.

Rebecca Lim: It would appear to be the case. So certainly the data that we have around the mechanisms about how the cells work has all been preclinical…

Norman Swan: By that you mean in a test tube and in animals.

Rebecca Lim: In animals. So we've done that across a number of different animal models to try and capture various aspects of this very complicated disease. And so taking that data along with our safety data we are now embarking on a phase two trial where we will be escalating.

Norman Swan: But we've jumped one step which is this study you've just published which is where you took six babies with bronchial pulmonary dysplasia, and tell me what you did with them?

Rebecca Lim: So these were six babies that already had BPD, so they were at Monash Newborn. They were born extremely premature, so 24 to 28 weeks of gestation. And as soon as they had established bronchial pulmonary dysplasia we approached the parents to see if they would be happy to be enrolled in our trial. These babies then received one dose of cells intravenously. We then followed them up.

Norman Swan: How did you know they were going to get to the lungs?

Rebecca Lim: So that's what we came across with all of our preclinical data. So there are a couple of things. One is that the cells will home to where there is injury, and we've seen that across 10 years' worth of preclinical research. The other thing is just because of the cardiopulmonary circulation, so if you inject something intravenously, the lungs almost end up as a net. So in terms of targeting the lungs, that was a fairly simple task.

Norman Swan: Because from the right side of the heart it just flushes the lungs with those. So this was a safety study because there's potential risks in doing this sort of thing. How did the babies go, safety wise?

Rebecca Lim: Absolutely. So with the very first…this is a first in humans, so with our very first human, that very first baby, it was a learning step for us. So what we learned was that the cells needed to be infused over a longer period of time and in a larger volume.

Norman Swan: Rebecca Lim is at the Hudson Institute of Medical Research at Monash University.