Christine Mummery: ‘People need to know what is and is not possible’

Christine Mummery, professor and head of the Anatomy and Embryology department at Leiden University Medical Center (LUMC), studies the effects of certain substances in the heart and blood vessels. Without the use of lab animals. She considers the transition to innovation without the use of animals from a scientist's nuanced perspective, meaning she sees both obstacles and opportunities.

‘Here in our lab, we work with human stem cells, which are similar to embryonic stem cells. The difference is that, instead of obtaining the cells from embryos, we develop them from the tissue of adults and children. These stem cells have the same genetic material as the person from whom the tissue was obtained, which includes any genetic anomalies that might lead to illness. Then we turn those stem cells into heart cells and vascular cells like in blood vessels.’

Prof. Christine Mummery (links) met haar collega dr. Susana Chuva de Sousa Lopes in het lab op het LUMC.


‘With these cells, in turn, we can create models for testing substances. Bits of cardiac tissue – we call them mini-hearts – but also chips with vascular tissue in which we simulate blood circulation. We use these models to determine what substances pose a risk to the cardiac and vascular functions of the human body. They're also used in the search for new treatments for cardiovascular diseases.’

In other words: Mummery uses what are known as ‘human measurement models’ in her work. This is not necessarily because she wants to avoid animal testing, but because she wants to conduct her research as effectively as possible. ‘Mice and rats, the animals most commonly used in medical research, are a poor simulation of the human heart. Their hearts beat 500 times per minute, while a human heart beats only 60 times. Their bodies also respond differently to infection. If you're trying to learn how certain medicines will affect the cardiac rhythm in humans, a mouse heart isn't going to be of much use to you. Toxic substances frequently affect heart rate as well – and something that is potentially fatal for humans won't necessarily kill a mouse. With that in mind, we'll happily go the extra mile to create a human measurement model.’


There are all kinds of cardiac studies out there. ‘Heart valves and similar devices are tested using dogs. These studies can't be carried out in a Petri dish. My specific type of research can, even though in the past it was done using canine hearts as well. The only animal model that might be more effective at predicting results in humans is a primate. These days, almost no one here in the Netherlands is willing to work with primates. In China, however, they do, and some parts of those studies are scientifically superior right now – for instance, where genetic change is concerned.’

‘We'll happily go the extra mile to create a human measurement model’

The only problem is that it remains difficult to predict whether substances that have a certain effect in Asians will have exactly the same effect in people of African ethnicity. In any case, every substance must be tested in a great many aspects, not only within the relevant organ but with regard to side effects in other parts of the body as well. Not much overlap exists between all these types of research. And that's without even mentioning research into other organs, bodily functions and diseases. Like cancer research, for example, which is impossible without the use of animal testing.


Mummery: ‘I'm fortunate to have a choice, and I avoid animal testing whenever possible. Our department used to have a lot of animal permits, but now it has hardly any. It depends on the objectives of the research. We haven't been able to dispense with animal testing entirely here in Leiden.’

Mummery feels scientists have a duty to take part in the societal discourse. ‘It can be difficult at times to convey the nuances, both to politicians and to the general public. Still, remaining on the sidelines is often the wrong decision. As a professional group, we're the ones who must supply the facts, to provide a sound basis for subsequent decision-making. The debate is vulnerable to influence from incorrect assumptions. People need to know what is and is not possible, and you can't make a silk purse from a sow's ear.’

‘Working together to identify the best predictive models is stronger motivation for researchers than developing models that don't rely on animal testing’


So according to Mummery, what is crucial to the transition to innovation without the use of animal testing? ‘We must look for the solution at an international level. Countries like China and the US, who focus on creating the most effective drugs possible, demand animal testing. The concept of eliminating animal testing is more of a ‘thing’ in Europe, although here we're more concerned with the price. For most pharmaceutical concerns, their major sales market and interests are in America, and they'll continue with animal testing even if, as a result, Europe no longer wants their products. But if we do want those products, for instance if they're better, we often have to carry out animal testing here anyway in order to meet the registration requirements.’

Which means a unilateral decision to abolish animal testing won't work. ‘In that case, we'd miss out on lots of medicines.’ Consensus is needed, first at the European and then at the global level.  Another issue is the difference in approaches. ‘In the US, for instance, they pay more attention to gender differences than we do. There, they test on both sexes. But when we use dogs in the Netherlands, they're always male. That's rather an important aspect when you’re studying effects on fertility, for example.’

Prof. Christine Mummery (rechts) met haar collega dr. Susana Chuva de Sousa Lopes in het lab op het LUMC.
Christine Mummery (rechts) met haar collega dr. Susana Chuva de Sousa Lopes.

‘In our type of research, we're better off using stem cell systems; I'm sure of it. And I'm being quite sincere when I say that in some cases, human models already have greater predictive value. Even in studies where lab animals are absolutely essential, I expect that to change in the next two or three years. Sometimes money concerns have a positive impact: animal testing is time-consuming and exorbitantly expensive, so technology might allow us to develop new medicines faster and more economically.’

‘Pharmaceutical companies will be happy to have alternatives, but the regulators must be convinced as well. To do this, we must first come up with evidence within the existing European systems. Some countries in Europe are more rigid about continuing animal testing than others. And once you've finally met all the requirements in Europe, you'll still have to start from scratch in the US or elsewhere. The FDA (the American Food & Drug Administration, red) doesn't simply transfer registrations from the EMA (the European Medicine Agency, red). This is why we need to open a dialogue in the international community. That way, we can gradually, one type of study and one aspect at a time, replace animal models with human models. While this process will be a lengthy one, the Netherlands has a chance to be the frontrunner.’


Mummery stresses that, in such efforts, it's crucial that better science be the top priority. ‘Working together to identify the best predictive models is stronger motivation for researchers than developing models that don't rely on animal testing. And scientists are creative enough to see where the opportunities are and where animal testing isn't the most effective method. Take blood poisoning and schizophrenia, for instance: these conditions don't affect mice. Such niches offer space for innovation without the use of animal testing.’