Review Articles in 2019

This Review focuses on evidence implicating innate lymphoid cells (ILCs) as previously unappreciated regulators of the adaptive immune system. Reciprocal interactions between ILCs and adaptive immune cells are a crucial determinant of tissue immune responses during homeostasis and disease.

Mucosal-associated invariant T cells display innate, effector-like qualities and are involved, in various ways, in infectious and non-infectious diseases. Insights into their activation, tissue migration and function are revealing their beneficial and deleterious roles in disease.

Sleep enhances immune defences, and afferent signals from immune cells promote sleep. However, in response to chronic stressors, the normally adaptive function of sleep can become dysregulated, with implications for inflammatory and antiviral responses.

Ultraviolet radiation (UVR) modulates innate and adaptive immune responses at both local and systemic levels; understanding the mechanisms of this immunomodulatory capacity can explain how UVR has both beneficial and detrimental effects.

New findings indicate that IFN-λ (type III IFN) has a non-redundant role in antiviral, antifungal and antiprotozoal defences of mucosal barriers that differs in several aspects from the functions of IFN-α and IFN-β (type I IFNs).

It is well known that immune cells can have profound effects on bone cells, but this interaction is not unidirectional. In this review, Tsukasaki and Takayanagi explore the reciprocal dialogue between bone cells and immune cells during health and disease.

This Review describes how the body attempts to maintain a functional T cell compartment with advancing age. It explores whether T cell ageing reflects cellular senescence or the failure to maintain quiescence and instead undergo differentiation.

Exercise is known to have beneficial effects on the immune system. In this Review, Janet Lord and colleagues discuss the evidence that exercise can prevent diseases associated with ageing by protecting against immunosenescence.

Vaccine trials against Mycobacterium tuberculosis (Mtb) are showing encouraging results. This Review discusses current Mtb vaccine design in the light of new insights into the immunology of tuberculosis infection.

Tuft cells captured the attention of immunologists with recent discoveries linking them to type 2 immunity in the small intestine. As described here, these rare secretory epithelial cells act as chemosensory sentinels that detect and relay responses through immune and neuronal cells.

This Review covers new insights into the immune roles of complement. The authors discuss the pathways that link complement signalling with homeostatic and pathological T cell responses and highlight how complement components act intracellularly to shape T cell responses.

The NLRP3 inflammasome mediates pro-inflammatory responses and pyroptotic cell death. Here, the authors describe the complex pathways controlling its activation and regulation and how it is being targeted to treat inflammatory diseases.

In this Review, Greg Lemke explains how macrophages are able to sense and respond to dead and dying cells. The author discusses the physiological implications of such macrophage activity.

This Review presents evidence that supports a role for the immune system in the pathogenesis of hypertension, including the immune cell subsets involved and the means by which these immune cells become activated throughout the course of the disease.

Here, Ho and Kupper detail how T cell responses are generated and maintained in skin. They discuss how the various subsets of skin-resident T cells — including memory and innate-like populations — contribute to inflammatory skin disorders.

John Harty and colleagues explain how different subsets of CD4⁺ T cells, CD8⁺ T cells and γδ T cells respond to the Plasmodium parasites that cause malaria. They discuss the major challenges that need to be overcome in order to harness T cell responses for malaria vaccines and therapies.

Some immune cells undergo processes that pose unique challenges to the 3D organization of their genomes. These include antigen receptor rearrangement, clonal expansion and the contortion of their nuclei. Here, Allan and colleagues discuss the latest insights into these processes from a structural genomics perspective.

This Review describes the diverse and dynamic chromatin modifications that ensure rapid and appropriate innate immune responses to infection. It also discusses how pathogens themselves modify host responses through epigenetic mechanisms to evade elimination.

This Review considers the link between pain and the immune system. Nociceptors are directly activated by immune mediators and microbial products and, in turn, release neuropeptides that shape immune responses. These neuroimmune pathways can contribute to protective immunity from infections but also lead to chronic pain.

The intestinal microbiota profoundly shapes host physiology through its production of small molecules and metabolites. Here, Honda and colleagues discuss how these microbial products shape immune function. They further consider the potential of ‘mining’ the microbiota for new microbial and metabolite-based immunotherapies.