RNA binding proteins help T cells pick their weapons before battle

RNA binding proteins help T cells pick their weapons before battle

Key points:

  • Researchers have identified key drivers of T cell development which promote resilience to influenza virus infection.
  • RNA binding proteins in the early stages of T cell activation are determining the quality of the T cell response to infection.
  • The absence of these RNA binding proteins during the initial phase of immune response leads to a stronger immune response to influenza.
  • These findings could lead the way for deliberate manipulation of the immune system for example when T cells are used to treat cancer.

Scientists at the Babraham Institute have shown that two RNA binding proteins hold the key to a stronger immune response to influenza in mice. Their findings, published today in Nature Communications, reveal that the absence of these proteins changes the potency of T cells that arise at the start on an infection. Further research could lead to implications for therapies that harness the immune system, and for vaccine design.

Researchers from the Turner lab focussed on the activity of the RNA binding proteins ZFP36 and ZFP36L1. By studying mice lacking these RNA binding proteins, the researchers were able to show that their absence in T cells during the initial phase of a viral infection leads to a superior cytotoxic immune response.

When the researchers infected mice with influenza, the ones lacking their RNA binding proteins in T cells showed signs of fighting the infection more successfully than those with the proteins present. They also transferred cells that lacked ZFP36 and ZFP36L1 into normal mice and found that even small numbers of transferred T cells provided the same advantage when fighting an influenza infection.

Their results were surprising, explains Dr Georg Petkau, a postdoctoral researcher who led the work “One striking observation of our study is that although the absence of RNA binding proteins in T cells results in stable accelerated differentiation and enhanced cytotoxicity, this does not lead to signs of disease or tissue damage, which is often a logical consequence of overt cytotoxicity during an immune response.”

The researchers speculate that the lack of negative knock on effects could be due to accelerated viral clearance and could be explained by a faster resolution of infection in young mice. It would be interesting to see whether upon recurrent infections a large accumulation of memory cells which show enhanced cytotoxicity in absence of RNA binding proteins would become potentially dangerous with age. Understanding how these RNA binding proteins limit T cell activation may thus also have implications for autoimmune disease formation in aged individuals.

The priming of the immune response once a pathogen is detected is a critical step which significantly changes the course of an immune response; it is the point at which immune cells decide to adjust the quality and duration of the immune response to a threat. In a sense the T cells in this study have to choose their weapons before they start to battle the infection and this choice is made by RNA binding proteins. By understanding more about how the immune system processes information within hours of infection and how RNA binding proteins integrate signals to activate T cells, the researchers hope to inform how we approach vaccine design and cell therapies.

“Going forward we want to investigate how the absence of RNA binding proteins affects the formation of immune memory and whether the superior cytotoxic traits acquired early in the response are epigenetically imprinted and maintained in the memory phase.” explained Dr Martin Turner, head of the Immunology research programme. Therefore the researchers will seek to explain their findings by investigating how the stable cytotoxic programme is set up early after activation by looking at changes in the epigenome.

Notes to Editors

Publication reference
Petkau, G., Mitchell, T.J., Chakraborty, K. et al. The timing of differentiation and potency of CD8 effector function is set by RNA binding proteins. Nat Commun 13, 2274 (2022). https://doi.org/10.1038/s41467-022-29979-x

Press contact
Honor Pollard, Communications Officer, honor.pollard@babraham.ac.uk

Image description:

Affiliated authors (in author order):

Georg Petkau, postdoctoral researcher, Turner lab
Twm Mitchell, postdoctoral researcher, Turner lab
Krishnendu Chakraborty, former postdoctoral researcher
Sarah Bell, Senior research associate, Turner lab
Vanessa D´Angeli, former PhD student, Turner lab
Louise Matheson, Turner lab
David Turner, postdoctoral researcher, Turner lab
Alexander Saveliev, postdoctoral researcher, Turner lab
Ozge Gizlenci, PhD student, Turner lab
Fiamma Salerno, EMBO Fellow, Turner lab
Martin Turner, Head of the Immunology research programme

Research funding
This research was supported by funding from the BBSRC. Martin Turner is a European Molecular Biology Organization Long-Term Fellow.

Additional/related resources:
Turner lab page

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As a publicly funded research institute, the Babraham Institute is committed to engagement and transparency in all aspects of its research. Animals are only used in Babraham Institute research when their use is essential to address a specific scientific goal, which cannot be studied through other means. All mouse experimentation was approved by the Babraham Institute Animal Welfare and Ethical Review Body. Genetically modified mice were used in this research to understand the role of specific proteins in T cell development. Mice were infected with influenza virus and their body weight monitored.

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About the Babraham Institute
The Babraham Institute undertakes world-class life sciences research to generate new knowledge of biological mechanisms underpinning ageing, development and the maintenance of health. Our research focuses on cellular signalling, gene regulation and the impact of epigenetic regulation at different stages of life. By determining how the body reacts to dietary and environmental stimuli and manages microbial and viral interactions, we aim to improve wellbeing and support healthier ageing. The Institute is strategically funded by the Biotechnology and Biological Sciences Research Council (BBSRC), part of UK Research and Innovation, through Institute Strategic Programme Grants and an Institute Core Capability Grant and also receives funding from other UK research councils, charitable foundations, the EU and medical charities.

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