Immunogenicity and tolerability in infants of a New Zealand epidemic strain meningococcal B outer membrane vesicle vaccine.

BACKGROUND: An outer membrane vesicle meningococcal vaccine (MeNZB), was developed for the New Zealand epidemic strain of Neisseria meningitidis B:4:P1.7-2,4. METHODS: A phase II, randomized, observer blind, controlled study evaluating the safety, reactogenicity, and immunogenicity of MeNZB administered with routine New Zealand immunizations at 6 weeks, 3 months, and 5 months of age (n = 375). Group 1 (n = 250) received 25 mug MeNZB and routine immunizations with a fourth MeNZB dose given at 10 months (n = 51). Group 2 (n = 125) received routine immunizations only. Sero-response was a > or =4-fold rise in vaccine strain serum bactericidal antibody titer compared with baseline or a titer of at least 1:8 for baselines <1:4. Reactogenicity was monitored for 7 days after vaccination. RESULTS: Sero-response in Group 1 was achieved in 53% (95% Confidence interval [CI]: 46-59, n = 239) and 69% (95% CI: 54-80, n = 45) with geometric mean antibody titers of 9 (95% CI: 7-10) and 22 (95% CI: 12-39) after the third and fourth doses, respectively. No negative interference by MeNZB on routine immunizations was detected. There were no serious adverse events judged to be vaccine related. CONCLUSIONS: In this group of New Zealand infants, 4 MeNZB doses were required to demonstrate titers comparable with those achieved after 3 doses in older children. MeNZB was safe when used concomitantly with routine New Zealand immunizations to 5 months of age.

Electroporation of corrective nucleic acids (CNA) in vivo to promote gene correction in dystrophic muscle.

Non-viral gene transfer into skeletal muscle in vivo is enhanced by electroporation (EP) to efficiencies far beyond any other (non-EP) method reported to date. Electroporation consistently delivers high levels of transgene to muscle and has been used extensively for the delivery of therapeutic transgenes to dystrophic mouse muscle such as the mdx mouse model of human Duchenne muscular dystrophy (DMD). Since the earliest applications, electroporation has consistently and reproducibly achieved highly efficient DNA delivery to a high proportion (greater than 70%) of fibres in treated muscles. This manuscript describes a methodology for introduction of corrective nucleic acids (CNAs) for the purpose of correcting the dystrophin gene (DMD ( mdx )) mutation responsible for muscular dystrophy in the mdx mouse model of human DMD by targeted corrective gene conversion (TCGC).

Cardiac outcome up to 15 years after the arterial switch operation.

AIMS: To assess the cardiac outcome and risk factors for mortality of infants following the arterial switch operation (ASO). METHODS: A single-centre retrospective review was conducted. Preoperative assessment, operative management and outcome was detailed for 244 patients undergoing the ASO at Green Lane Hospital for transposition of the great arteries (TGA) or double outlet right ventricle. RESULTS: The postoperative survival at 1, 5 and 15 years was 85%, 84% and 83%, respectively. The calendar year of ASO and the presence of a ventricular septal defect (VSD) were the primary predictors of early mortality. Late mortality was associated with a side-by-side configuration of the great arteries. Re-intervention following ASO was more common in patients with prolonged cardiopulmonary bypass time. CONCLUSIONS: Low early and late morbidity and mortality can be obtained in infants with TGA or double outlet right ventricle by definitive repair utilising the ASO.

Congenital aneurysm of the muscular interventricular septum in association with cardiac arrhythmias and a chromosomal abnormality.

We report a newborn with a congenital aneurysm of the muscular interventricular septum, a conduction system abnormality involving variable left and right bundle branch block, and an abnormality of the short arm of chromosome 20, This combination of anomalies has not been previously reported. To date, the infant has progressed well from a cardiac perspective but has poor muscle tone and developmental delay.

Evaluation of Sca-1 and c-Kit as selective markers for muscle remodelling by nonhemopoietic bone marrow cells.

Bone marrow (BM)-derived cells (BMCs) have demonstrated a myogenic tissue remodeling capacity. However, because the myoremodeling is limited to approximately 1%-3% of recipient muscle fibers in vivo, there is disagreement regarding the clinical relevance of BM for therapeutic application in myodegenerative conditions. This study sought to determine whether rare selectable cell surface markers (in particular, c-Kit) could be used to identify a BMC population with enhanced myoremodeling capacity. Dystrophic mdx muscle remodeling has been achieved using BMCs sorted by expression of stem cell antigen-1 (Sca-1). The inference that Sca-1 is also a selectable marker associated with myoremodeling capacity by muscle-derived cells prompted this study of relative myoremodeling contributions from BMCs (compared with muscle cells) on the basis of expression or absence of Sca-1. We show that myoremodeling activity does not differ in cells sorted solely on the basis of Sca-1 from either muscle or BM. In addition, further fractionation of BM to a more mesenchymal-like cell population with lineage markers and CD45 subsequently revealed a stronger selectability of myoremodeling capacity with c-Kit/Sca-1 (p < .005) than with Sca-1 alone. These results suggest that c-Kit may provide a useful selectable marker that facilitates selection of cells with an augmented myoremodeling capacity derived from BM and possibly from other nonmuscle tissues. In turn, this may provide a new methodology for rapid isolation of myoremodeling capacities from muscle and nonmuscle tissues. Disclosure of potential conflicts of interest is found at the end of this article.

DNA electroporation in vivo targets mature fibres in dystrophic mdx muscle.

Non-viral gene transfer into skeletal muscle is enhanced by electroporation and myotoxin preconditioning of muscle following plasmid injection. We investigated in vivo delivery of naked DNA to mdx mouse muscle, utilising enhanced green fluorescent protein reporter vector (pEGFP) and a corrective nucleic acid to promote targeted corrective gene conversion at the mutant mdx mouse dystrophin (DMDmdx) locus. Electroporation, myoablation with bupivacaine and a combined protocol, were applied to mdx muscle. We report up to 90% EGFP expression in electroporated mdx tibialis anterior muscle. Muscles preconditioned with bupivacaine showed low transgene expression with or without EP. Single EGFP+ve muscle fibre explants showed EGFP expression in mature fibres in preference to satellite cells. We observed a two-fold increase (P<0.005; t) in dystrophin protein, accompanied by wild-type (wt) DMD transcript in muscles injected with corrective nucleic acid over contralateral saline-injected TAs. By targeting the muscle fibres in preference to the satellite cells, plasmid-bourne transgenes delivered to dystrophic muscle will not penetrate the regenerative component of muscle. Whether in the context of targeted corrective gene conversion or therapeutic non-viral transgenes, under these conditions periodic re-administration will be required to promote phenotypic benefits in dystrophic muscle.