Hot off the presses! Sep 01 Nat Rev Immunol

The Sep 01 issue of the Nat Rev Immunol is now up on Pubget (About Nat Rev Immunol): if you're at a subscribing institution, just click the link in the latest link at the home page. (Note you'll only be able to get all the PDFs in the issue if your institution subscribes to Pubget.)

Latest Articles Include:

• From the editors
  - Nat Rev Immunol 9(9):601 (2009)
  
• Phagocytosis: Don't eat the HSCs
  - Nat Rev Immunol 9(9):603 (2009)
  
• Thymocyte development: The identification of THEMIS
  - Nat Rev Immunol 9(9):604 (2009)
  
• Viral immunity: Are men and women different?
  - Nat Rev Immunol 9(9):604 (2009)
  
• T cell development: Lead role for BCL-6 in TFH cell development
  - Nat Rev Immunol 9(9):605 (2009)
  
• Natural killer cells: Stop, look, listen
  - Nat Rev Immunol 9(9):606 (2009)
  
• In brief: Regulatory T cells, Immune responses, Phagocytosis
  - Nat Rev Immunol 9(9):606 (2009)
  
• Inflammation: Finding the T in fat
  - Nat Rev Immunol 9(9):607 (2009)
  
• Interdependence of hypoxic and innate immune responses
  - Nat Rev Immunol 9(9):609-617 (2009)
  Hypoxia-inducible factor (HIF) is an important transcriptional regulator of cell metabolism and the adaptation to cellular stress caused by oxygen deficiency (hypoxia). Phagocytic cells have an essential role in innate immune defence against pathogens and this is a battle that takes place mainly in the hypoxic microenvironments of infected tissues. It has now become clear that HIF promotes the bactericidal activities of phagocytic cells and supports the innate immune functions of dendritic cells, mast cells and epithelial cells. In response to microbial pathogens, HIF expression is upregulated through pathways involving the key immune response regulator nuclear factor-B, highlighting an interdependence of the innate immune and hypoxic responses to infection and tissue damage. In turn, HIF-driven innate immune responses have important consequences for both the pathogen and the host, such that the tissue microenvironment fundamentally influences susceptibility to infecti! ous disease.
• Stromal cell contributions to the homeostasis and functionality of the immune system
  - Nat Rev Immunol 9(9):618-629 (2009)
  A defining characteristic of the immune system is the constant movement of many of its constituent cells through the secondary lymphoid tissues, mainly the spleen and lymph nodes, where crucial interactions that underlie homeostatic regulation, peripheral tolerance and the effective development of adaptive immune responses take place. What has only recently been recognized is the role that non-haematopoietic stromal elements have in many aspects of immune cell migration, activation and survival. In this Review, we summarize our current understanding of lymphoid compartment stromal cells, examine their possible heterogeneity, discuss how these cells contribute to immune homeostasis and the efficient initiation of adaptive immune responses, and highlight how targeting of these elements by some pathogens can influence the host immune response.
• Rho family GTPases and their regulators in lymphocytes
  - Nat Rev Immunol 9(9):630-644 (2009)
  Rho family GTPases, and the proteins that regulate them, have important roles in many cellular processes, including cell division, survival, migration and adhesion. Although most of our understanding of these proteins has come from studies using cell lines, more recent gene targeting studies in mice are providing insights into the in vivo function of these proteins. Here we review recent progress revealing crucial roles for these proteins in lymphocyte development, activation, differentiation and migration. The emerging picture shows that Rho family GTPases transduce signals from receptors for antigens, chemokines and cytokines, as well as adhesion molecules and pattern recognition receptors, and that they function as focal points for crosstalk between different signalling pathways.
• Cytokine determinants of viral tropism
  - Nat Rev Immunol 9(9):645-655 (2009)
  The specificity of a given virus for a cell type, tissue or species — collectively known as viral tropism — is an important factor in determining the outcome of viral infection in any particular host. Owing to the increased prevalence of zoonotic infections and the threat of emerging and re-emerging pathogens, gaining a better understanding of the factors that determine viral tropism has become particularly important. In this Review, we summarize our current understanding of the central role of antiviral and pro-inflammatory cytokines, particularly the interferons and tumour necrosis factor, in dictating viral tropism and how these cytokine pathways can be exploited therapeutically for cancer treatment and to better counter future threats from emerging zoonotic pathogens.
• Signalling crosstalk in B cells: managing worth and need
  - Nat Rev Immunol 9(9):657-661 (2009)
  The B cell receptor (BCR) and the receptor for B cell-activating factor (BAFFR) have complementary roles in B cells: BCR signals provide a cell-intrinsic measure of suitability for negative or positive selection, whereas BAFFR responds to homeostatic demands based on a cell-extrinsic measure of the size of the mature B cell pool. Because continuous signals from both receptors are required for B cell survival, it is probable that there are mechanisms to integrate the selective and homeostatic signals from these receptors. In this Opinion article, I describe recent evidence to indicate that crosstalk between the downstream biochemical pathways of these receptors mediates this interdependence, such that BCR signals generate a limiting substrate for BAFFR signal propagation.
• The precursors of memory: models and controversies
  - Nat Rev Immunol 9(9):662-668 (2009)
  The adaptive immune system has evolved a unique capacity to remember a pathogen through the generation of memory T cells, which rapidly protect the host in the event of reinfection. How memory T cells develop and the relationship between effector and memory T cells has been actively debated in the literature for many years and several models have been proposed to explain the divergent developmental fates of T cell progeny. Here, Nature Reviews Immunology asks four leading researchers in the field to provide their thoughts and opinions on the ontogeny of memory T cells and its implications for vaccine design.