Tell us a little about yourself; how long have you been working with flow cytometry?
I first started in cytometry rather than flow cytometry in 1980. In fact, on my second working day, I came across a static cytometer, which was used to measure DNA content in cells on slides. I got into flow cytometry in 1985, which was a good time to get into it because it wasn't commercially available at that point. So, people were floundering a little bit in terms of how it worked. There was a lot of self-help in the early days, which was great.
At that time, I was part of an MRC-funded project to look at whether you could use flow cytometry to pre-screen cervical specimens. Turns out you can't really, but it showed me that flow cytometry was a very versatile technique, and I realised that this was something that immunologists in particular would find useful because they were spending a lot of time looking at fluorescently labelled cells under a microscope. I got the idea that flow cytometry would be a good technique to be a core technology, and I ended up moving to what was then the Imperial Cancer Research Fund in London, which had one of the first core facilities in the country, and I was there for over 20 years, eventually running the facility. The institute was one of the founding bodies of the Francis Crick Institute, so I spent a lot of time building a new facility, and towards the end of my career I took on an internal role where I was looking at training and setting up training procedures for in all of our core facilities.
How many people would you say you've trained in your entire career?
Probably somewhere approaching 10,000, I would think. You know, virtually every PhD student will use flow cytometry to some degree. And it's a very widespread technology now.
How has flow cytometry’s role in modern immunology changed?
In terms of immunology, it's always been a technique that immunologists have wanted to use. But if we go back 40 odd years, the cytometers weren't as capable as they are today. We didn't have as many fluorescent reagents as we have today. So, the principles are the same; it's just that we've managed to up the number of things that we can measure.
And of course, that's a big advantage if you've got a heterogeneous population like you often have in peripheral blood. You can look at many, many different cells subsets very quickly. And not only that, you can start asking them questions. So, you can look at cytokine production, you can look at phosphoprotein signalling, and so on. And we can do that now all in one tube.
What are the most common misconceptions immunologists have about flow cytometry?
Immunology is probably the biggest driver of flow cytometry. I always get a list of applications during training and phenotyping is right up there. In terms of the biggest misconception, people will read a paper where they're looking at 20 or 30 different markers and think they're going to be able to do that the following day. So, there's a lot of management of expectations.
You need to understand, first of all, how the machines work. You need to understand how you can combine things. And there's a need for data analysis as well.
The basic principles of any experiment are always the same. You need to think about your biological question, you need to think about the reagents that you have, and you need to think about the cytometer that you have. But the trouble is that those three things are different for every person.
If you turn up in a lab, somebody gives you a protocol, and it works – that's brilliant. But as soon as it goes wrong, you've got to troubleshoot that. Designing flow experiments is a lot like plate spinning. There are a lot of things you've got to think about, and they all interact with each other.
Beyond the lab, how does flow cytometry expertise open doors for people in their careers?
Flow is a fantastic transferable skill. If you're in the biomedical research world, you'll come across flow cytometry, and it's available in all walks of life, not just in the research environment. Clinically, it's used for diagnostic purposes. You have cytometers in the brewing industry, water companies, and so on.
It also opens doors if you don't necessarily want to be a career scientist. We now have a lot of core facilities in most institutes, and if you've got that flow aptitude, that's exactly what I'd be looking for in staff. And because it's big business, of course, you've also got that opportunity to move into industry, whether it's application specialists or selling reagents agents or working in a pharma or CRO company.
You’ve been working with the BSI to deliver flow cytometry for immunologists for nearly two years now. What are some of the common challenges immunologists have in designing or analysing cytometry experiments?
We're aiming the course at people who are relatively new. Ideally, they'd have a little bit of knowledge of flow cytometry, but the courses are about designing panels.
We have an online portal where delegates can look at some videos before they come on the course, which gives them an idea of the principles, how flow cytometers work, and so on. Then in the main part of the course, we focus on the experimental design. But I think in general, it's maybe in the first six months of your career, you've done a little bit and you want to consolidate that knowledge and get a little bit extra knowledge.
There's also a live element to the training where people bring their questions to try and make it as interactive as possible. So it's a combination of didactic teaching and breakout rooms, which have been very successful. The feedback is very good around those.
What would you encourage people to specifically look out for when choosing a training course?
If you’re looking for a course, I think you want something that is a little bit interactive that allows you to speak with the trainers. With any course that I run, there's always a needs assessment beforehand. We send out questionnaires in advance to understand the skill level and the expectations that the delegates have.
If you're an immunologist, you want people who are going to be able to answer immunologically relevant questions. You're looking for people with experience; you're looking for a course that isn't just sitting in front of a screen and listening to somebody for three hours.
Immunologists need to constantly learn new skills, particularly with new technologies such as AI. Do you have any advice for what immunologists should look to do to stay competitive?
Well, I think that they do need to be a little bit more au fait with programming languages, particularly R and Python. The people working with genomics are producing lots of data as well. So, it’s really knowing how to deal with that data and put it into context of your biological question.
We don't want to get to the stage where you press a few buttons and AI pops something out at the other end. You've got to make sure that that the answers make sense at the end of it. There will always be a need for understanding the basic principles, what you’ve done, and how you apply that to the data that you've got. There's much more integration now. Thirty-odd years ago, you would just do a flow cytometry experiment and publish that. But now you've got to integrate that with all sorts of multi-omic technologies, each of which has its own particular challenges.
What kind of techniques have you employed throughout your training career to help people learn better?
Traditionally, training would all be done through classroom-based sessions, because there was no other way of delivering it. But now, we have lots of different ways of doing it, including face-to-face, virtual training and there’s also just YouTube videos.
I’ve been focused on developing a proper e-learning system which is a combination of didactic teaching videos and live forums. That then gives everybody an opportunity to access information. Obviously since the pandemic, everybody is much more used to looking for things online or getting that information online. But I also like the idea of building a network of experts who could deliver courses locally so that in-person live course content would be the same, but it would be run at different places, meaning people wouldn't have to travel.
Interviewed by Laura Cox