An important clinical characteristic of dengue shock syndrome is increased vascular permeability. The actin cytoskeleton represents a significant element of endothelial barrier function regulation, but it is not precisely clear what role actin plays during infection. Wang et al. show the participation of Rac1 signaling pathways in viral protein-induced actin reorganizations, which may be a mechanism involved in dengue hemorrhagic fever.
The cytokine osteopontin (OPN) is involved in several immune responses that occur during bacterial infections such as melioidosis. Van der Windt and colleagues found that OPN concentrations were elevated in people with severe melioidosis, and that high OPN concentrations are associated with poor outcome in those patients. In their experiments involving mice, those that were OPN deficient demonstrated reduced bacterial numbers in their lungs, diminished pulmonary tissue injury, decreased neutrophil infiltration, and even delayed mortality.
To understand the effects of schistosome infection on hosts' biochemistry associated with disease progression and to detect disease earlier, Wu and colleagues investigated the metabolite composition changes in mouse tissue induced by Schistosoma japonicum. Their results demonstrate metabonomics as a potentially useful tool for early diagnosis of S. japonicum infections.