Gresham College’s Professor of Physic to give talk on Wednesday, 2 October, at 6pm, in central London and live online.

Invisible to the naked eye, it is easy not to think about singular-cell creatures like bacteria or viruses until they cause us trouble, such as a bout of food poisoning or a cold.

But these miniscule creations are complex organisms, complete with a unique immune system that sees them fight their own battles against bugs.

For his first lecture of the 2024-25 academic year Professor Robin May will ask Do Microbes Have Immune Systems? and lift the lid on the astonishingly diverse immune mechanisms used by bacteria, amoebae, nematodes, and many other microbial forms of life in their constant battle against viruses and each other.

Entry is free (advanced booking essential) and, like all Gresham lectures will be streamed live on the Gresham website and YouTube channel, free of charge.

Professor May said: “Although we are very familiar with our own immune systems, most people are unaware that plants or bacteria also have immune systems.

“In this first lecture we will explore the extraordinarily diverse ways in which bacteria and other microbes protect themselves from infection. We will also discuss recent interest in using bacteriophages (viruses that target bacteria) as alternatives to antibiotics.

“One of the main immune mechanisms in bacteria is a system called Clustered Regularly Interspaced Palindromic Repeats, or CRISPR. This provides bacteria with a highly specific way to destroy attacking viruses, but in recent years we have been able to harness the same system as a genetic engineering tool.

“It is now used around the world for plant and animal breeding and for the treatment of otherwise-fatal genetic diseases in humans. It is a spectacular example of why learning more about microbial immunity can have major benefits for humanity”

Professor May will also explore what he describes as “slightly weirder types of immunity,” such as that shown by some amoebae.

“Some so-called social amoebae live most of their lives as single cells but occasionally aggregate into a kind of multicellular body” he said. “Within that aggregate, some of those individual cells start to act rather like white blood cells in our own bodies, consuming invading bacteria and then killing themselves to protect the cells around them. It is similar to how our immune systems work, but in a completely different way.”

Professor May says the aim of his series is to make immunology accessible to everyone, regardless of scientific background: “There is absolutely no way we could, or should, be trying to give people a crash course in immunology – there are entire degree programmes to do that. Instead, my aim across the series is to highlight the fascinating bits, the fun bits, the bits that might captivate people’s attention and hopefully spark their interest in learning more about the amazing immune cells that keep them alive.”

Gresham College is London’s oldest higher education institution. Founded in 1597 under the will of Sir Thomas Gresham, it has been delivering free public lectures for over 427 years from a lineage of leading professors and experts in their field who have included Christopher Wren, Robert Hooke, Iannis Xenakis and Sir Roger Penrose.

In-person places can be booked online via Gresham College’s website:

gresham.ac.uk/whats-on/microbes-immunity