Adaptive T cells regulate disease tolerance in human malaria

Diana Muñoz Sandoval, Florian Bach, Wiebke Nahrendorf, Alasdair Ivens, Michalina Mazurczyk, Yrene Themistocleous, Sarah E. Silk, Jordan R. Barrett, Nick J. Edwards, Giorgio Napolitani, Angela M. Minassian, Simon J. Draper, Philip J. Spence

Research output: Working paperPreprint

Abstract

Immunity to severe malaria is acquired quickly, operates independently of pathogen load and represents a highly effective form of disease tolerance. The mechanism that underpins tolerance in human malaria remains unknown. We developed a re-challenge model of falciparum malaria in which healthy naive adult volunteers were infected three times over a 12-month period to track the development of disease tolerance in real-time. We found that parasitaemia triggered a hardwired emergency myeloid response that led to systemic inflammation, pyrexia and hallmark symptoms of clinical malaria across the first three infections of life. In contrast, CD4+ T cell activation was quickly modified to reduce the number and diversity of effector cells upon re-challenge. Crucially, this did not silence critical helper T cell functions but instead prevented the generation of cytotoxic effectors associated with autoinflammatory disease. Tolerised hosts were thus able to prevent collateral tissue damage and injury. Host control of T cell activation can therefore be established after a single infection and in the absence of anti-parasite immunity. And furthermore, this rapid host adaptation can protect vital organs to minimise the harm caused by systemic inflammation and sequestration. Immunity to severe malaria is acquired quickly, operates independently of pathogen load and represents a highly effective form of disease tolerance. The mechanism that underpins tolerance in human malaria remains unknown. We developed a re-challenge model of falciparum malaria in which healthy naive adult volunteers were infected three times over a 12-month period to track the development of disease tolerance in real-time. We found that parasitaemia triggered a hardwired emergency myeloid response that led to systemic inflammation, pyrexia and hallmark symptoms of clinical malaria across the first three infections of life. In contrast, CD4+ T cell activation was quickly modified to reduce the number and diversity of effector cells upon re-challenge. Crucially, this did not silence critical helper T cell functions but instead prevented the generation of cytotoxic effectors associated with autoinflammatory disease. Tolerised hosts were thus able to prevent collateral tissue damage and injury. Host control of T cell activation can therefore be established after a single infection and in the absence of anti-parasite immunity. And furthermore, this rapid host adaptation can protect vital organs to minimise the harm caused by systemic inflammation and sequestration.
Original languageEnglish
PublishermedRxiv
Number of pages68
DOIs
Publication statusPublished - 24 Aug 2021

Fingerprint

Dive into the research topics of 'Adaptive T cells regulate disease tolerance in human malaria'. Together they form a unique fingerprint.

Cite this