Review Articles in 2008

Recent studies of T-cell leukaemia have provided insight into the molecular mechanisms responsible for the induction and progression of this disease. As discussed here, many of the genes that are dysregulated in T-cell leukaemia are known to be involved in T-cell development.

Episodes of acute inflammation must be resolved to avoid tissue damage and chronic disease. Three families of lipid mediators — lipoxins, resolvins and protectins — actively promote the resolution of inflammation through multiple mechanisms, as discussed in this Review.

In this Review, Jenny Ting and colleagues discuss the role of the NLR (nucleotide-binding domain, leucine-rich repeat containing) family proteins in various forms of cell death, including two newly recognized types of cell death — pyroptosis and pyronecrosis.

The TAM receptors — TYRO3, AXL and MER — are emerging as important regulators of innate immune responses. Here, the authors describe their roles in inhibiting inflammation driven by antigen-presenting cells, in promoting phagocytosis of apoptotic cells and in stimulating maturation of natural killer cells.

Multiparameter flow cytometry can not only assess the phenotype and magnitude of a T-cell response, but based on effector function, its quality. As discussed here, the quality of a T-cell response is crucial for defining protective cellular immunity, and has great implications for vaccine design.

Natural killer (NK) cells are known to provide a first line of defence against viruses. Here, Lewis Lanier highlights the receptors and effector mechanisms used by NK cells in the protection against viruses and discusses how, reciprocally, viruses have evolved strategies to avoid activation of these cells.

The development of a diverse B-cell repertoire depends on genetic rearrangement and hypermutation at the B-cell receptor (BCR) loci. This Review describes which DNA polymerases might be involved in these DNA transactions and therefore contribute to BCR diversity.

To avoid potential damage to the host, an inflammatory response is rapidly mobilized on detection of intracellular signals that are released from dying cells. Much has been learned about these 'danger' signals, but several key issues remain unresolved, as discussed by the authors.

Maintenance of haematopoietic stem cells occurs in niches, but much discussion still surrounds the precise site and nature of these niches. Here, Mark Kiel and Sean Morrison review various niche models that are compatible with the recent published data.

A number of susceptibility genes for asthma and allergy have been identified in recent years. Here, Donata Vercelli discusses these genes and reviews the techniques used by geneticists to identify them. She also highlights the outstanding challenges in the field.

Recent advances in the structural determination of IgE and its receptors and associated molecules have provided insight into the functions and regulation of IgE. This is now helping to direct the design of new IgE-targeted therapies for asthma and allergy.

In addition to providing a physical barrier, epithelial cells have a role in initiating and maintaining allergic responses to inhaled allergens. As discussed in this Review, epithelial cells can influence the polarization of lung dendritic cells and are themselves influenced by innate and adaptive immune responses during allergic inflammation.

In addition to conventional interactions between receptors and ligands on opposing cells (trans interactions), some MHC-class-I-specific receptors interact with their ligands on the same cell (cis interactions). Here, the structural characteristics and functional outcome of cisinteractions are discussed.

Understanding the mechanisms of allergic inflammation is important for the improvement of current therapies and the development of novel therapies. This Review describes the current therapeutic strategies for allergy and asthma and highlights several innovative future strategies.

Asthma and chronic obstructive pulmonary disease both involve chronic inflammation of the lungs. But Peter Barnes explains how the inflammatory mediators and cells involved differ between the two diseases and how this affects their responsiveness to corticosteroids and other anti-inflammatory therapies.

Here, John Harty and Vladimir Badovinac describe the factors that control the generation of memory CD8⁺ T cells, discuss how these factors can characterize this response and highlight how the manipulation of these factors could reshape CD8⁺T-cell memory.

Views about the differentiation pathways of haematopoietic-cell lineages are evolving. No longer viewed as a series of binary fate decisions, evidence is emerging for the divergence, convergence and reversibility of haematopoiesis, as described here for B-cell development.

The immune system has evolved specific mechanisms to deal with the unique problems encountered in the specialized microenvironment of the lung. This Review discusses the key mechanisms through which the local immune system maintains immunological homeostasis in the lung while preserving the integrity of the gas-exchange surfaces.

Studies inDrosophila melanogasterare proving fruitful for our understanding of phagocytosis in development, tissue homeostasis and host defence. In this Review, parallels are drawn between phagocytosis in flies and mammals, providing insight into its complexity and the evolutionary origins of immunity.

In this article, the authors provide a description of microRNA production and function, and discuss what is currently known about the role of microRNAs in the development and function of immune cells and in host–virus interactions.