Multivalent human antibody-centyrin fusion protein to prevent and treat Staphylococcus aureus infections.

Treating and preventing infections by antimicrobial-resistant bacterial pathogens is a worldwide problem. Pathogens such as Staphylococcus aureus produce an array of virulence determinants, making it difficult to identify single targets for the development of vaccines or monoclonal therapies. We described a human-derived anti-S. aureus monoclonal antibody (mAb)-centyrin fusion protein ("mAbtyrin") that simultaneously targets multiple bacterial adhesins, resists proteolysis by bacterial protease GluV8, avoids Fc engagement by S. aureus IgG-binding proteins SpA and Sbi, and neutralizes pore-forming leukocidins via fusion with anti-toxin centyrins, while maintaining Fc- and complement-mediated functions. Compared with the parental mAb, mAbtyrin protected human phagocytes and boosted phagocyte-mediated killing. The mAbtyrin also reduced pathology, reduced bacterial burden, and protected from different types of infections in preclinical animal models. Finally, mAbtyrin synergized with vancomycin, enhancing pathogen clearance in an animal model of bacteremia. Altogether, these data establish the potential of multivalent mAbs for treating and preventing S. aureus diseases.

Selective silencing of Na(V)1.7 decreases excitability and conduction in vagal sensory neurons.

There has been much information learned in recent years about voltage gated sodium channel (Na(V)) subtypes in somatosensory pain signalling, but much less is known about the role of specific sodium channel subtypes in the vagal sensory system. In this study, we developed a technique using adeno-associated viruses (AAVs) to directly introduce shRNA against Na(V)1.7 subtype gene into the vagal sensory ganglia of guinea pigs in vivo. Na(V)1.7 gene expression in nodose ganglia was effectively and selectively reduced without influencing the expression of other sodium channel subtype genes including Na(V)1.1, 1.2, 1.3 1.6, 1.8, or 1.9. Using a whole cell patch-clamp technique, this effect on Na(V)1.7 gene expression coincided with a reduction in tetrodotoxin-sensitive sodium current, a requirement for much larger depolarizing stimulus to initiate action potentials, and reduction in repetitive action potential discharge. Extracellular recordings in the isolated vagus nerve revealed that the conduction of action potentials in sensory A- and C-fibres in many neurons was effectively abolished after Na(V)1.7 shRNA introduction. Moreover, bilateral Na(V)1.7 shRNA injected animals survived for several months and the vagal reflex behaviour, exemplified by citric acid-induced coughing, was significantly suppressed. These data indicate that selectively silencing Na(V)1.7 ion channel expression leads to a substantial decrease in neural excitability and conduction block in vagal afferent nerves.

Staging of head and neck tumors: [18F]fluorodeoxyglucose positron emission tomography compared with physical examination and conventional imaging modalities.

PURPOSE: The aims of this study were to evaluate the use of [(18)F]fluorodeoxyglucose positron emission tomography (FDG-PET) in the staging of primary and recurrent tumors of the head and neck in comparison to routine clinical methods (physical examination, ultrasonography, computed tomography) and to investigate the effect of FDG-PET scanning on therapeutic strategy. MATERIALS AND METHODS: Retrospective analysis of the results of FDG-PET and conventional diagnostic modalities were compared with biopsy results or patient outcome or both. In a period of 6 years, 78 FDG-PET studies were performed on 56 patients; 24 of them before therapy and 54 on suspicion of residual or recurrent tumor. The evaluation of the diagnostic results was performed separately for the primary site and the nodal sites of the neck and for tumor occurrence in the trunk. RESULTS: In detecting the primary site, FDG-PET results reached a sensitivity of 93%, a specificity of 100%, and an accuracy of 94%. In detecting the nodal sites, similar results of 94%, 97%, and 96% were seen, respectively. In detecting tumor occurrence in the trunk, results were 83%, 100%, and 98%, respectively. The McNemar test did not prove any statistically significant difference between FDG-PET and the evaluated conventional methods. When used in conjunction with conventional diagnostic tests, 22% of the PET scans gave important additional information. Finally, 11% of the performed PET scans led to a change in therapeutic planning. CONCLUSIONS: Our results show that FDG-PET is a reliable method to detect tumors in all tumor sites. Therefore, we recommend that FDG-PET scanning be performed routinely as a first diagnostic step in pretherapeutic staging of patients with biopsy-proven head and neck cancer.

Functional and binding studies of HS3.2 of the beta-globin locus control region.

The distal locus control region (LCR) is required for high-level expression of the complex of genes (HBBC) encoding the beta-like globins of mammals in erythroid cells. Several major DNase hypersensitive sites (HSs 1-5) mark the LCR. Sequence conservation and direct experimental evidence have implicated sequences within and between the HS cores in function of the LCR. In this report we confirm the mapping of a minor HS between HS3 and HS4, called HS3.2, and show that sequences including it increase the number of random integration sites at which a drug resistance gene is expressed. We also show that nuclear proteins including GATA1 and Oct1 bind specifically to sequences within HS3.2. However, the protein Pbx1, whose binding site is the best match to one highly conserved sequence, does not bind strongly. GATA1 and Oct1 also bind in the HS cores of the LCR and to promoters in HBBC. Their binding to this minor HS suggests that they may be used in assembly of a large complex containing multiple regulatory sequences.