Tuesday, 02 November 2021
Scientists have discovered that a deadly parasite, known to cause ill health in pregnant women and immunocompromised patients, could potentially be used to treat various types of tumours.
The research, published today in the Journal for ImmunoTherapy Cancer, was carried out by experts from the University of Nottingham, Ningbo University and Shanxi Agricultural University in China.
Improving the effectiveness of treatments against certain types of tumours is vital in order to beat certain cancers, stop tumour progression, and prolong the lives of patients. In this new study, scientists revealed that a parasite found commonly across the globe, is able to sensitise cold tumours - tumours that are not likely to trigger a strong immune response by the body – to immune checkpoint blockade therapy.
Scientists leading the study believe that this finding could have broader therapeutic implications for many types of cancers.
The team managed to ‘tame’ the parasite Toxoplasma gondii - a single-celled opportunistic protozoan capable of infecting a broad range of warm-blooded animals and has been reported in nearly one-third of the world’s human population.
Toxoplasma gondii must live inside the cells of its host and secretes many proteins to counter the host’s immune defences and to facilitate their own invasion and colonisation of the host cells. The researchers first built a Toxoplasma gondii mutant strain with a limited ability to grow, in cultured cells or to cause disease in mice, but at the same time is able to manipulate the host immune system.
The researchers have shown that direct injection with this mutant parasite in solid tumours, induces inflammatory responses in the injected tumours and even in tumours located in a distant location in the mouse body. They have also shown that this treatment approach has made tumours more responsive to treatment with immune checkpoint inhibitor.
This dual treatment significantly extended the survival of mice and reduced tumour growth in mouse models of melanoma, Lewis lung carcinoma, and colon adenocarcinoma.
Dr Hany Elsheikha, Associate Professor in the School of Veterinary Medicine and Science at the University of Nottingham, and one of the lead authors of the study, said: “The use of a mutant version of Toxoplasma gondii in the treatment of certain tumours in mice models has been previously reported. What makes this study different is the confirmation that intratumoral injection with mutant Toxoplasma gondii strain boosts antitumor immunity and the effectiveness of checkpoint inhibition therapy.
“These are significant findings and are relevant to future tumour therapy. The marked reduction in tumour size and the significant improvement in the survival of mice that received this novel combinational therapy is promising but should be interpreted with caution as further research is needed.”
The full study can be found here.
More information is available from Dr Hany Elsheikha in the School of Veterinary Medicine Medicine at Hany.Elsheikha@nottingham.ac.uk
Notes to editors:
The University of Nottingham
Our academics can now be interviewed for broadcast via our Media Hub, which offers a Quicklink fixed camera and ISDN line facilities at Jubilee campus. For further information please contact a member of the Press Office on +44 (0)115 951 5798, email firstname.lastname@example.org
For up to the minute media alerts, follow us on Twitter
The University of Nottingham is a research-intensive university with a proud heritage. Studying at the University of Nottingham is a life-changing experience, and we pride ourselves on unlocking the potential of our students. We have a pioneering spirit, expressed in the vision of our founder Sir Jesse Boot, which has seen us lead the way in establishing campuses in China and Malaysia - part of a globally connected network of education, research and industrial engagement. Ranked 18th in the UK by the QS World University Rankings 2023, the University’s state-of-the-art facilities and inclusive and disability sport provision is reflected in its crowning as The Times and Sunday Times Good University Guide Sports University of the Year twice in three years, most recently in 2021. We are ranked seventh for research power in the UK according to REF 2021. We have six beacons of research excellence helping to transform lives and change the world; we are also a major employer and industry partner - locally and globally. Alongside Nottingham Trent University, we lead the Universities for Nottingham initiative, a pioneering collaboration which brings together the combined strength and civic missions of Nottingham’s two world-class universities and is working with local communities and partners to aid recovery and renewal following the COVID-19 pandemic.