Research Highlights in 2021

Antihistamines can enhance efficacy of immune checkpoint blockade therapy in cancer.

The RNA helicase DDX17 is identified as the sensor for a non-canonical NLRC4–NLRP3 inflammasome activated by endogenous retrotransposons in sterile inflammation.

A mRNA vaccine induces ‘tick immunity’ in guinea pigs and reduces the transmission of Lyme disease.

This study links the complement-mediated retraction of T helper 1 cell responses to vitamin D receptor signalling, an autoregulatory loop that might be impaired in patients with COVID-19.

B cell-derived GABA can inhibit T cell and macrophage activation and limit anti-tumour T immune responses.

Transient skin inflammation in early life leads to the development of T helper 2 cell–fibroblast niches that alter wound repair responses and may drive fibrotic pathology later in life.

Enteric glial cells regulate intestinal homeostasis and immunity by responding to IFNγ.

Genetic variants in apolipoprotein L1 (APOL1) — present only in individuals of African ancestry — contribute to increased susceptibility to sepsis and COVID-19. APOL1 variants impair mitophagy in endothelial cells, allowing the release of mitochondrial DNA that activates inflammasome and nucleotide sensing pathways.

New research shows that red blood cells express surface TLR9 that binds cell-free DNA, leading to erythrophagocytosis and innate immune activation.

A breakdown in host symbiosis with commensal microorganisms in the skin can lead to the destruction of hair follicles by innate lymphoid cells.

Blind mole rats are resistant to cancer. A new study describes how activation of transposons triggers an innate immune response that eliminates premalignant cells.

A new study explores the links between diet and colorectal cancer risk by showing that changes to the intestinal microbiome in mice fed a high-fat diet result in attenuated MHC class II expression by intestinal stem cells and hence impaired immune surveillance of tumour initiation.

A new study describes the extensive transcriptional remodelling that occurs in neutrophils during inflammation, detailing the transcription factors that control neutrophil maturation and effector functions.

The type 2 cytokine TSLP acts on T cells to promote sebum secretion and uses up lipids in this process, leading to loss of white adipose tissue.

Intestinal IgA responses to commensal fungi are mutualistic, selecting for fungi that are less pathogenic and more fit.

Endogenous retroviruses act as inner adjuvants to prime T cell responses against skin commensals.

A new study in Cell provides a single-cell map of the epigenetic and transcriptomic landscape in response to influenza vaccination, revealing persistent epigenomic remodelling in myeloid cells and the antiviral effects of adjuvant.

A new study in Cell provides a cellular atlas of the oral mucosa, revealing complex stromal–immune cell interactions that support inflammatory responsiveness and neutrophil recruitment.

This study reports serum metabolome profiling of children naturally infected with Plasmodium falciparum in Burkina Faso, West Africa, revealing major changes in endogenous steroid levels with effects on adaptive immunity.

A new study in Nature shows that sensory neurons communicate with dermal macrophages after sunburn-like skin damage to favour healing over inflammation.