Do the ends justify the means? Impact of drought progression rate on stress response and recovery in Vitis vinifera.

Plants are frequently exposed to prolonged and intense drought events. To survive, species must implement strategies to overcome progressive drought while maintaining sufficient resources to sustain the recovery of functions. Our objective was to understand how stress rate development modulates energy reserves and affects the recovery process.

Chemical inhibition of xylem cellular activity impedes the removal of drought-induced embolisms in poplar stems - new insights from micro-CT analysis.

In drought-stressed plants a coordinated cascade of chemical and transcriptional adjustments occurs at the same time as embolism formation. While these processes do not affect embolism formation during stress, they may prime stems for recovery during rehydration by modifying apoplast pH and increasing sugar concentration in the xylem sap. Here we show that in vivo treatments modifying apoplastic pH (stem infiltration with a pH buffer) or reducing stem metabolic activity (infiltration with sodium vanadate and sodium cyanide; plant exposure to carbon monoxide) can reduce sugar accumulation, thus disrupting or delaying the recovery process.

Cutting edge: A critical functional role for IL-23 in psoriasis.

Interleukin-23 is a key cytokine involved in the generation of Th17 effector cells. Clinical efficacy of an anti-p40 mAb blocking both IL-12 and IL-23 and disease association with single nucleotide polymorphisms in the IL23R gene raise the question of a functional role of IL-23 in psoriasis. In this study, we provide a comprehensive analysis of IL-23 and its receptor in psoriasis and demonstrate its functional importance in a disease-relevant model system.

Interplay between keratinocytes and immune cells--recent insights into psoriasis pathogenesis.

Psoriasis is one of the most common human inflammatory skin diseases characterised by hyperproliferation and aberrant differentiation of keratinocytes. The trigger of the typical epidermal changes seen in psoriasis was considered to be a dysregulated immune response with Th-1/Tc1 cells playing a central role. Recent studies have provided new insights into psoriasis pathogenesis in defining intraepidermal alpha(1)beta(1)+ T cells as key effectors driving keratinocyte changes.

Alpha1beta1 integrin is crucial for accumulation of epidermal T cells and the development of psoriasis.

Psoriasis is a common T cell-mediated autoimmune inflammatory disease. We show that blocking the interaction of alpha1beta1 integrin (VLA-1) with collagen prevented accumulation of epidermal T cells and immunopathology of psoriasis. Alpha1beta1 integrin, a major collagen-binding surface receptor, was exclusively expressed by epidermal but not dermal T cells.

The pathogenic role of tissue-resident immune cells in psoriasis.

Psoriasis is a common chronic inflammatory skin disease, the study of which might also be of considerable value to the understanding of other inflammatory and autoimmune-type diseases, such as rheumatoid arthritis, inflammatory bowel disease, multiple sclerosis and diabetes mellitus. There is clear evidence that T cells and dendritic cells have a central role in psoriasis. Based on recent data from humans and animal models, we propose that a psoriasis lesion can be triggered and sustained by the local network of skin-resident immune cells.

Cancer vaccines: the next generation of tools to monitor the anticancer immune response.

Nestle and colleagues discuss a new immunomonitoring tool, described by Chen et al. in that may give insight into the vaccine-induced anticancer immune response.