is the most common cause of bacterial meningitis in children and young adults worldwide. A 4-component vaccine against serogroup B (MenB) disease (MenB-4C [Bexsero]; GSK) combining factor H binding protein (fHBP), neisserial heparin binding protein (NHBA), neisserial adhesin A (NadA), and PorA-containing outer membrane vesicles was recently approved for use in the United States and other countries worldwide. Because the public health impact of MenB-4C in the United States is unclear, we used the meningococcal antigen typing system (MATS) to assess the strain coverage in a panel of strains representative of serogroup B (NmB) disease in the United States. MATS data correlate with killing in the human complement serum bactericidal assay (hSBA) and predict the susceptibility of NmB strains to killing in the hSBA, the accepted correlate of protection for MenB-4C vaccine. A panel of 442 NmB United States clinical isolates (collected in 2000 to 2008) whose data were down weighted with respect to the Oregon outbreak was selected from the Active Bacterial Core Surveillance (ABCs; CDC, Atlanta, GA) laboratory. MATS results examined to determine strain coverage were linked to multilocus sequence typing and antigen sequence data. MATS predicted that 91% (95% confidence interval [CI], 72% to 96%) of the NmB strains causing disease in the United States would be covered by the MenB-4C vaccine, with the estimated coverage ranging from 88% to 97% by year with no detectable temporal trend. More than half of the covered strains could be targeted by two or more antigens. NHBA conferred coverage to 83% (CI, 45% to 93%) of the strains, followed by factor H-binding protein (fHbp), which conferred coverage to 53% (CI, 46% to 57%); PorA, which conferred coverage to 5.9%; and NadA, which conferred coverage to 2.5% (CI, 1.1% to 5.2%). Two major clonal complexes (CC32 and CC41/44) had 99% strain coverage. The most frequent MATS phenotypes (39%) were fHbp and NHBA double positives. MATS predicts over 90% MenB-4C strain coverage in the United States, and the prediction is stable in time and consistent among bacterial genotypes. The meningococcal antigen typing system (MATS) is an enzyme-linked immunosorbent assay (ELISA)-based system that assesses the levels of expression and immune reactivity of the three recombinant MenB-4C antigens and, in conjunction with PorA variable 2 (VR2) sequencing, provides an estimate of the susceptibility of NmB isolates to killing by MenB-4C-induced antibodies. MATS assays or similar antigen phenotype analyses assume importance under conditions in which analyses of vaccine coverage predictions are not feasible with existing strategies, including large efficacy trials or functional antibody screening of an exhaustive strain panel. MATS screening of a panel of NmB U.S. isolates ( = 442) predicts high MenB-4C vaccine coverage in the United States.

Prostate cancer (PCa) disease progression is associated with significant changes in intracellular and extracellular proteins, intracellular signaling mechanism, and cancer cell phenotype. These changes may have direct impact on the cellular interactions with nanocarriers; hence, there is the need for a much-detailed understanding, as nanocarrier cellular internalization and intracellular sorting mechanism correlate directly with bioavailability and clinical efficacy. In this study, we report the differences in the rate and mechanism of cellular internalization of a biocompatible polycaprolactone (PCL)/maltodextrin (MD) nanocarrier system for intracellular drug delivery in LNCaP, PC3, and DU145 PCa cell lines. PCL/MD nanocarriers were designed and characterized. PCL/MD nanocarriers significantly increased the intracellular concentration of coumarin-6 and fluorescein isothiocyanate-labeled bovine serum albumin, a model hydrophobic and large molecule, respectively. Fluorescence microscopy and flow cytometry analysis revealed rapid internalization of the nanocarrier. The extent of nanocarrier cellular internalization correlated directly with cell line aggressiveness. PCL/MD internalization was highest in PC3 followed by DU145 and LNCaP, respectively. Uptake in all PCa cell lines was metabolically dependent. Extraction of endogenous cholesterol by methyl-β-cyclodextrin reduced uptake by 75%±4.53% in PC3, 64%±6.01% in LNCaP, and 50%±4.50% in DU145, indicating the involvement of endogenous cholesterol in cellular internalization. Internalization of the nanocarrier in LNCaP was mediated mainly by macropinocytosis and clathrin-independent pathways, while internalization in PC3 and DU145 involved clathrin-mediated endocytosis, clathrin-independent pathways, and macropinocytosis. Fluorescence microscopy showed a very diffused and non-compartmentalized subcellular localization of the PCL/MD nanocarriers with possible intranuclear localization and minor colocalization in the lysosomes with time.

No abstract

BackgroundMaternal vaccines against pertussis are not yet recommended in the developing world. Besides unclear burden estimates, another concern is that transplacental transfer of maternal pertussis antibodies could result in attenuation of the immune response to whole cell pertussis (DTwP) primary vaccination series in infants. This study was taken up to determine whether higher levels of maternal pertussis antibodies attenuate immune response of infants to DTwP vaccination series given at 6–10–14 weeks of age.MethodologyA total of 261 pregnant women and their infants from four low-income settlements in Karachi, Pakistan were enrolled in this study. The study endpoints were infant antibody titers for Pertussis toxin (PTx), Filamentous hemagglutinin antigen (FHA), Pertactin (PRN) and Fimbriae type 2/3 (FIM) – from birth through 18 weeks of age. Cord blood or pre-vaccine pertussis antibody titers indicate the concentration of maternal antibodies transferred to infants. Linear regression models were used to determine the association between higher maternal antibody titers and infant immune response to DTwP vaccine. Geometric Mean Ratio (GMR) was calculated as the ratio of infant antibody titers at specified time points against the maternal antibody titers at the time of delivery.ResultsAt eighteen weeks of age, the adjusted β regression coefficient for PTx was 0.06 (95% CI: -0.49-0.61), FHA 0.02 (95% CI: -0.26 -0.29), PRN 0.02 (95%CI -0.38- 0.43), and FIM 0.17 (95%CI: -0.21-0.54). Among infants who received at least two doses of DTwP vaccine, higher maternal antibody titers did not have any attenuating effect on infant post-immunization antibody titers against all four pertussis antigens.ConclusionMaternal pertussis antibodies did not attenuate infant’s immune response to pertussis antigens in DTwP primary vaccine given at 6–10–14 weeks of age.