Microscopic, single cell differences found in the lungs of COVID-19 patients in Malawi demonstrates the vital importance of a global approach to the understanding and treatment of infectious disease.
The new study conducted by Malawi-Liverpool-Wellcome Research Programme (MLW), the University of Glasgow, Kamuzu University of Health Sciences and Liverpool School of Tropical Medicine (LSTM)– the first of its kind in sub-Saharan Africa –reveals previously unobserved differences in the inflammatory response to SARS-CoV-2, the virus that causes COVID-19, in those who died from the disease in Malawi, compared to those who live in the Global North.
Scientists believe these differences in response to the virus may be linked to both genetic and environmental factors, highlighting the importance of a global approach to infectious disease research.
The findings, published in Nature Medicine, suggest that some treatments used for COVID-19 in Asia, Europe, and North America might not be as effective in a Malawian population. The results identify unique potential therapeutic ‘targets’ for tailored interventions.
Single cell genomic analysis is cutting-edge scientific technique that potentially unlocks more targeted and effective treatments, but until now almost all single cell research has been conducted in the Global North. Future single cell research at MLW aims to shine new light on vaccine failure in Malawi and other low- and-middle income countries, potentially informing the next generation of vaccines for a range of infectious diseases.
Dr Kayla Barnes, Senior Lecturer at MLW and LSTM and co-last author on the study said: “Single-cell genomic analysis gives us a very deep look at immune responses but almost all of this work has occurred in the Global North. At MLW we have built a robust single-cell genomics programme and this paper highlights how single-cell genomics can elucidate immune response differences across populations.”
Associate Professor Kondwani Jambo, Reader in Immunology and Infection at MLW and LSTM and a co-author on the study, said: “This paper enhances the global human single-cell atlas data and closely aligns with our AfricAsia Single Cell Genomics Initiative's mission. The initiative seeks to comprehensively characterise immune responses to infectious diseases across various underrepresented African and Asian populations, tackling pressing infection-related challenges, while enriching the diversity of the human single-cell atlas."
To carry out the study, published in Nature Medicine, the team undertook a series of postmortem investigations in fatal lung disease patients, with and without COVID-19, in the early stages of the pandemic (2020-21). Seeking to understand how the disease had impacted people in Malawi, the team carried out single cell tests on lung and nasal tissues as well as on blood samples, alongside using imaging mass cytometry – a cutting-edge imaging technology.
Dr Christopher Moxon, lead author of the paper from the University of Glasgow, said: “It is great to see the results come together of this major multi-disciplinary team effort. The work had social, logistical as well as technical challenges and it was only through bringing together local and international experts in these areas that this study was possible. Our team has shown that we can apply some of the most cutting-edge techniques in a centre in sub–Saharan Africa and produce results with important translational implications. This lays exciting foundations for the future.”
James Nyirenda, first author on the paper who carried out the research while at the MLW and Kamuzu University of Health Sciences, said: “Our study highlights the need for investing in advanced discovery research in low-income regions. This is not just about scientific innovation; it’s also about bringing equal benefits of scientific innovation to under-represented countries for equity. By uncovering unique immune responses to COVID-19 in Malawi, our study highlights how targeted immunological research can lead to more effective, accessible treatments for populations that might otherwise be overlooked.”
The paper, ‘Spatially resolved single-cell atlas of the lung in fatal Covid19 in an African population reveals a distinct cellular signature and an interferon gamma dominated response’ is published in Nature Medicine. The work was funded by The Bill and Melinda Gates Foundation, a UKRI Future Leaders Fellowship award and the Wellcome Trust.