Volume 11 Issue 11, November 2011

Therapeutic targeting of inflammatory monocyte migration attenuates disease severity.

Identification of human T memory stem cells with increased therapeutic potential.

BCR endocytosis compartmentalizes kinase phosphorylation and downstream signalling.

The inhibitory signal to T cells through PD1 is sustained during chronic viral infection by epigenetic mechanisms.

Self-reactive T cells invade and are degraded in hepatocytes, preventing autoimmune disease.

Type I IFN targets CD8α⁺DCs for the initiation of antitumour immunity.

Activated T cells induce the production of immunosuppressive nitric oxide by stromal cells.

Acetylcholine-producing T cells convey neural signals to dampen inflammation.

Most regulatory T cells in the colon are specific for commensal bacteria.

Macrophages exhibit remarkable plasticity and adopt pro- or anti-inflammatory phenotypes in response to environmental signals. This Review article by Murray and Wynn discusses the different macrophage subsets and their contribution to tissue homeostasis and disease pathogenesis.

Inflammation in adipose tissue is known to mediate insulin resistance in obesity, and macrophages are thought to have a central role in mediating this inflammatory response. But adipose tissue macrophages are not all bad: alternative activation of these cells promotes insulin sensitivity.

This Review describes the key transcription factors that enable the polarization of macrophages in response to the microenvironment in the context of a regulatory landscape that determines macrophage identity.

Monocytes serve as precursors for various tissue macrophage and dendritic cell populations and contribute to both protective and pathological immune responses. Here, the authors describe the mechanisms that are involved in mobilizing monocytes to distinct tissue sites, both during steady-state conditions and in response to infection.

Microglia are brain-resident macrophages with a distinct origin. This Review discusses the development and function of these cells, and describes the association between the different microglial cell phenotypes and disease.

Immunologists are making good progress in unravelling the intricacies of the mononuclear phagocyte system, and this is largely due to recent technological advances. This article describes the current tools that exist for studying the origins and functions of mononuclear phagocytes and discusses the future technologies that will enable further progress in the field.

Macrophages, first described at the end of the 19th century by Élie Metchnikoff, have a central role in maintaining tissue homeostasis but also provide signals for the activation of adaptive immune cells. The specially commissioned review articles in this Focus discuss our current understanding of the homeostatic and pathogenic functions — as well as the development, recruitment and transcriptional regulation — of monocytes and macrophages.