IL-17 and γδ T-lymphocytes play a critical role in innate immunity against Nocardia asteroides GUH-2

The early host response during pulmonary nocardiosis is highly dependent on neutrophils and the successful clearance of bacteria in tissue. The data presented in this study showed that IL-17 mediated the neutrophil response following intranasal inoculation with Nocardia asteroides strain GUH-2. Flow cytometry revealed that neutrophil levels in C57BL/6 mice were increased by day 1 post inoculation and remained elevated until day 3, during which time the majority of bacterial clearance occurred. Intracellular cytokine staining for IL-17 showed a 3.5- to 5-fold increase in IL-17 producing T-lymphocytes that were predominately comprised by CD4^?CD8^? γδ T-lymphocytes. The importance of IL-17 and γδ T-cells was determined by the in vivo administration of antibody, capable of blocking IL-17 binding or TCR δ, respectively. Neutralization of either IL-17 or γδ T-cells in Nocardia treated mice resulted in attenuated neutrophil infiltration. Paralleling this impaired neutrophil recruitment, nearly a 10-fold increase in bacterial burden was observed in both anti-IL-17 and anti-TCR δ treated animals. Together, these data indicate a protective role for IL-17 and suggest that IL-17 producing γδ T-lymphocytes contribute to neutrophil infiltration during pulmonary nocardiosis.     

DNA barcoding provides support for a cryptic species complex within the globally distributed and fishery important opah (Lampris guttatus)

The cornerstone of fisheries management relies on a solid taxonomic base and an understanding of how animals can be grouped into coherent management units. Surprisingly, little is known about the basic biology and ecology of opah (Lampris guttatus), a globally distributed species that is commercially exploited and regionally common in the North Pacific. Recent efforts to collect life history data on this species uncovered evidence of two North Pacific morphotypes. Sequencing of the mitochondrial cytochrome c oxidase I gene (655 bp) for these morphotypes and other specimens collected worldwide (n = 480) produced five strongly diverged and well‐supported clades. Additional sequence data from the cytochrome b gene (1141 bp) as well as the nuclear recombination activating gene 1 (1323 bp) corroborated these results, suggesting these five clades probably represent separate species. Our conclusion that opah is a complex of five separate species has implications for management and indicates a need to gather additional data on these poorly understood fishes.     

Visualization of pulmonary inflammation using noninvasive fluorescence molecular imaging.

The ability to visualize molecular processes and cellular regulators of complex pulmonary diseases such as asthma, chronic obstructive pulmonary disease (COPD), or adult respiratory distress syndrome (ARDS), would aid in the diagnosis, differentiation, therapy assessment and in small animal-based drug-discovery processes. Herein we report the application of normalized transillumination and fluorescence molecular tomography (FMT) for the noninvasive quantitative imaging of the mouse lung in vivo. We demonstrate the ability to visualize and quantitate pulmonary response in a murine model of LPS-induced airway inflammation. Twenty-four hours prior to imaging, BALB/c female mice were injected via tail vein with 2 nmol of a cathepsin-sensitive activatable fluorescent probe (excitation: 750 nm; emission: 780 nm) and 2 nmol of accompanying intravascular agent (excitation: 674 nm; emission: 694 nm). Six hours later, the mice were anesthetized with isoflurane and administered intranasal LPS in sterile 0.9% saline in 25 microl aliquots (one per nostril). Fluorescence molecular imaging revealed the in vivo profile of cysteine protease activation and vascular distribution within the lung typifying the inflammatory response to LPS insult. Results were correlated with standard in vitro laboratory tests (Western blot, bronchoalveolar lavage or BAL analysis, immunohistochemistry) and revealed good correlation with the underlying activity. We demonstrated the capacity of fluorescence tomography to noninvasively and longitudinally characterize physiological, cellular, and subcellular processes associated with inflammatory disease burden in the lung. The data presented herein serve to further evince fluorescence molecular imaging as a technology highly appropriate for the biomedical laboratory.     

Taste modifiers: parotid reflexes can differ from taste judgements

Sweetness-depressing gymnemic acid (G) and sweetness-inducingmiraculin (M) helped determine the extent to which parotid salivaryresponses match behavioral and neural gustatory responses. Parotidflow rates and tastes intensities were obtained from four subjectsfor four sweeteners (before and after G) and for citric acid(CA) before and after M and G. A mixture of 20 mM CA and 10%sucrose was also tested. Although G depressed sweetness forglucose, sucrose, fructose and aspartame, G generally failedto alter parotid responses or depress post-G ratings for bitterintensity. In fact, G markedly elevated parotid responses forthe acid–sucrose mixture. Residual sweetness after G,detected mainly from the posterior tongue, probably contributedonly partially to sustaining post–G parotid responses.We speculate that side tastes from the sweeteners and oral irritationfrom CA in the mixture contributed to elevated flow rates afterG. Sucrose- and M-induced sweetness generally elevated parotidresponses for 20 mM CA. This result agrees with human chordatympani responses after M but differs for sucrose–acidmixtures in that parotid responses approached the calculatedsum of the components. We speculate that non-gustatory inputsmay also affect sweet–sour responses and advise cautionin relating parotid reflexes only to taste judgements. ¹Present address: Department of Biological Sciences, San JoseState University, San Jose, CA 95192, USA     

Two new species ofDelitschia from submerged wood

Two new species ofDelitschia are described from submerged wood;D. palmietensis collected in the Palmiet River in Durban Westville, South Africa andD. fasciatispora from the Black River, Mauritius. This brings the total ofDelitschia species known from non-coprophilous habitats to four.Delitschia palmietensis andD. fasciatispora are described and illustrated with light micrographs and discussed in relation to other species in the genus. A key to the non-coprophilousDelitschia species is provided.