Tuberculosis, caused by the bacillus Mycobacterium tuberculosis, remains a global health problem accounting for over two million deaths annually (23). The ability to survive in host phagocytes is a poorly understood virulence property of M. tuberculosis. The M. tuberculosis proteins exported to the bacterial cell surface or secreted by the bacillus are ideally positioned to interact with host cell components and include virulence factors that promote intracellular survival.

Dengue viruses (DENV) are enveloped single-stranded positive-sense RNA viruses transmitted by Aedes spp. mosquitoes. There are four genetically distinct serotypes designated DENV-1 through DENV-4, each further subdivided into distinct genotypes. The dengue scientific community has long contended that infection with one serotype confers lifelong protection against subsequent infection with the same serotype, irrespective of virus genotype. However this hypothesis is under increased scrutiny and the role of DENV genotypic variation in protection from repeated infection is less certain. As dengue vaccine trials move increasingly into field-testing, there is an urgent need to develop tools to better define the role of genotypic variation in DENV infection and immunity. To better understand genotypic variation in DENV-3 neutralization and protection, we designed and constructed a panel of isogenic, recombinant DENV-3 infectious clones, each expressing an envelope glycoprotein from a different DENV-3 genotype; Philippines 1982 (genotype I), Thailand 1995 (genotype II), Sri Lanka 1989 and Cuba 2002 (genotype III) and Puerto Rico 1977 (genotype IV). We used the panel to explore how natural envelope variation influences DENV-polyclonal serum interactions. When the recombinant viruses were tested in neutralization assays using immune sera from primary DENV infections, neutralization titers varied by as much as ∼19-fold, depending on the expressed envelope glycoprotein. The observed variability in neutralization titers suggests that relatively few residue changes in the E glycoprotein may have significant effects on DENV specific humoral immunity and influence antibody mediated protection or disease enhancement in the setting of both natural infection and vaccination. These genotypic differences are also likely to be important in temporal and spatial microevolution of DENV-3 in the background of heterotypic neutralization. The recombinant and synthetic tools described here are valuable for testing hypotheses on genetic determinants of DENV-3 immunopathogenesis.

This study compared the ability of mosquito and mammalian cell-derived dengue virus (DENV) to infect human dendritic cell-specific ICAM3-grabbing non-integrin (DC-SIGN)-expressing cells and characterized the structure of envelope (E) protein N-linked glycans on DENV derived from the two cell types. DENVs derived from both cell types were equally effective at infecting DC-SIGN-expressing human monocytes and dendritic cells. The N-linked glycans on mosquito cellderived virus were a mix of high-mannose and paucimannose glycans. In virus derived from mammalian cells, the N-linked glycans were a mix of high-mannose and complex glycans. These results indicate that N-linked glycans are incompletely processed during DENV egress from cells, resulting in high-mannose glycans on viruses derived from both cell types. Studies with full-length and truncated E protein demonstrated that incomplete processing was most likely a result of the poor accessibility of glycans on the membrane-anchored protein. INTRODUCTIONDengue viruses (DENVs) are enveloped, positive-sense RNA viruses of the genus Flavivirus that are transmitted via the bite of Aedes mosquitoes. Each year, over 2.5 billion people are at risk of contracting dengue, 100 million people develop symptomatic infections and up to 2.5 % of dengue haemorrhagic fever (DHF) patients die (Gubler, 2002;Gubler & Clark, 1995; WHO, 2009). Despite the public health importance of dengue, the cell biology of DENV is poorly understood. Vector-borne viruses such as DENV must productively infect cells of both arthropod and mammalian origin. As the posttranslational protein-processing machinery is different in insect and mammalian cells, the structure of glycoproteins produced in the two hosts may be different. Recent work with a wide variety of viruses has shown that protein glycosylation can influence viral virulence (reviewed by Vigerust & Shepherd, 2007). Recent studies with alphaviruses, which are also transmitted by arthropod vectors, have demonstrated that membraneprotein N-linked oligosaccharides are differentially processed by enzymes in insect and mammalian cells (Shabman et al., 2008). Structural differences in the glycans derived from insect and mammalian cells influence the ability of the viruses to infect target cells (Klimstra et al., 2003;Shabman et al., 2007Shabman et al., , 2008. In this study, we characterized the N-linked glycans on the envelope protein of DENVs grown in different cell types and assessed the functional consequences of these differences.The DENV particle is made up of three structural proteins: envelope (E), membrane (M) and capsid (C) (Chambers et al., 1990b;Kuhn et al., 2002). The E protein is the major membrane glycoprotein on the surface of the virion, responsible for virus attachment and fusion (Chambers et al., 1990b). Human dendritic cells (DCs) are a target of DENV infection (Ho et al., 2001;Marovich et al., 2001;Wu et al., 2000). Infection of DCs is mediated by the binding of DENV to DC-specific ICAM3-grabbing non-integrin (DC-SIGN), a C-type lec...

PurposeThe ideal approach to complex ventral hernia repair is frequently debated. Differences in processing techniques among biologic materials may impact hernia repair outcomes. This study evaluates the outcomes of hernia repair with a terminally sterilized human acellular dermal matrix (TS-HADM) (AlloMax® Surgical Graft, by C. R. Bard/Davol, Inc., Warwick, RI, USA) treated with low-dose gamma irradiation.MethodsA single-arm multi-center retrospective observational study of patients undergoing hernia repair with TS-HADM was performed. Data analyses were exploratory only; no formal hypothesis testing was pre-specified.ResultsSeventy-eight patients (43F, 35M) underwent incisional hernia repair with a TS-HADM. Mean follow-up was 20.5 months. Preoperative characteristics include age of 56.6 ± 11.1 years, BMI 36.7 ± 9.9 kg/m2, and mean hernia defect size 187 cm2. Sixty-five patients underwent component separation technique (CST) with a reinforcing graft. Overall, 21.8 % developed recurrences. Recurrences occurred in 15 % of patients repaired with CST. Major wound complications occurred in 31 % of patients overall. Based upon CDC surgical wound classification, major wound complications were seen in 26, 40, 56, and 50 % of Class 1, 2, 3, and 4 wounds, respectively. No grafts required removal.ConclusionsHernia recurrences are not uncommon following complex abdominal wall reconstruction. Improved outcomes are seen when a TS-HADM is utilized as reinforcement to primary fascial closure.

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