Volume 9 Issue 8, August 2009

The activation and signalling pathways engaged by Toll-like receptors (TLRs) are determined by their localization in the cell. Here, the authors explain how generic cellular machinery involved in the compartmentalization of receptors and signalling molecules contributes to TLR function and regulation.

The more time you spend with someone, the bigger the impact that person has on you. And the same is true for lymphocytes. But what are the molecular and cellular processes that regulate intercellular contacts made by lymphocytes and how does the duration of these contacts modulate their effector functions?

Recent studies defining the structure of and signalling pathways used by receptors of the interleukin-17 family have led to interesting comparisons with the pro-inflammatory signalling pathways that are more commonly associated with innate immune receptors. Sarah Gaffen therefore suggests that T helper 17 cells might act as a bridge between innate and adaptive immunity.

Elimination of early neoplastic cells by innate immune cells is an important protective measure against cancer. Here, the authors explain that this tumour surveillance is linked to stress pathways that are activated during tumorigenesis through the induction of ligands for natural killer cell receptors, particularly NKG2D.

Exosomes can act as messengers, carrying biological information between cells. Here, the authors describe the numerous effects that exosomes have on immune cells and discuss how they might be harnessed to promote or limit immune responses for therapeutic purposes.

This Innovation article describes recently developed assays that measure the changing physiology within maturing phagosomes and discusses how studies using these techniques have shed light on the biological functions of phagosomes and phagocytes during innate and adaptive immune responses.