Local and Systemic Immunity against Respiratory Syncytial Virus Induced by a Novel Intranasal Vaccine. A Randomized, Double-Blind, Placebo-controlled Clinical Trial

RATIONALE:Needle-free intranasal vaccines offer major potential advantages, especially against pathogens entering via mucosal surfaces. As yet, there is no effective vaccine against respiratory syncytial virus (RSV), a ubiquitous pathogen of global importance that preferentially infects respiratory epithelial cells; new strategies are urgently required. OBJECTIVES:Here, we report the safety and immunogenicity of a novel mucosal RSV F protein vaccine linked to an immunostimulatory bacterium-like particle (BLP). METHODS:In this phase I, randomised, double-blind placebo-controlled trial, 48 healthy volunteers aged 18-49 years were randomly assigned to receive placebo or SynGEM (low- or high-dose) intranasally by prime-boost administration. The primary outcome was safety and tolerability, with secondary objectives assessing virus-specific immunogenicity. MEASUREMENTS AND MAIN RESULTS:There were no significant differences in adverse events between placebo and vaccinated groups. SynGEM induced systemic plasmablast responses and significant, durable increases in RSV-specific serum antibody in healthy seropositive adults. Volunteers given low-dose SynGEM (140 µg F, 2mg BLP) required a boost at day 28 to achieve plateau responses with a maximum fold-change of 2.4, whereas high-dose recipients (350 µg F, 5mg BLP) achieved plateau responses with a fold-change of 1.5 after first vaccination that remained elevated up to 180 days post-vaccination irrespective of further boosting. Palivizumab-like antibodies were consistently induced, but F protein site Ø-specific antibodies were not detected and virus-specific nasal IgA responses were heterogeneous, with strongest responses in individuals with lower pre-existing antibody levels. CONCLUSIONS:SynGEM is thus the first non-replicating intranasal RSV subunit vaccine to induce persistent antibody responses in human volunteers. Clinical trial registration available at www.clinicaltrials.gov, ID NCT02958540

Is red blood cell rheology preserved during routine blood bank storage?

BACKGROUND: Red blood cell (RBC) units stored for more than 2 weeks at 4 degrees C are currently considered of impaired quality. This opinion has primarily been based on altered RBC rheologic properties (i.e., enhanced aggregability, reduced deformability, and elevated endothelial cell interaction), during prolonged storage of nonleukoreduced RBC units. In this study, the rheologic properties and cell variables of leukoreduced RBC units, during routine blood bank storage in saline-adenine-glucose-mannitol, were investigated. STUDY DESIGN AND METHODS: Ten leukoreduced RBC units were stored at the blood bank for 7 weeks at 4 degrees C. RBCs were tested weekly for aggregability, deformability, and other relevant variables. RESULTS: RBC aggregability was significantly reduced after the first week of storage but recovered during the following weeks. After 7 weeks aggregability was slightly, but significantly, reduced (46.9 +/- 2.4-44.3 +/- 2.2 aggregation index). During storage the osmotic fragility was not significantly enhanced (0.47 +/- 0.01% phosphate-buffered saline) and the deformability at shear stress of 3.9 Pa was not significantly reduced (0.36 +/- 0.01 elongation index [EI]). The deformability at 50 Pa was reduced (0.58 +/- 0.01-0.54 +/- 0.01 EI) but remained within reference values (0.53 +/- 0.04). During 5 weeks of storage, adenosine triphosphate was reduced by 54% whereas mean cell volume, pH, and mean cell hemoglobin concentration were minimally affected. CONCLUSIONS: RBC biochemical and physical alterations during storage minimally affected the RBC ability to aggregate and deform, even after prolonged storage. The rheologic properties of leukoreduced RBC units were well preserved during 7 weeks of routine blood bank storage

Loop Grafting of Bacillus subtilis Lipase A: Inversion of Enantioselectivity

Lipases are successfully applied in enantioselective biocatalysis. Most lipases contain a lid domain controlling access to the active site, but Bacillus subtilis Lipase A (LipA) is a notable exception: its active site is solvent exposed. To improve the enantioselectivity of LipA in the kinetic resolution of 1,2-O-isopropylidene-sn-glycerol (IPG) esters, we replaced a loop near the active-site entrance by longer loops originating from Fusarium solani cutinase and Penicillium purpurogenum acetylxylan esterase, thereby aiming to increase the interaction surface for the substrate. The resulting loop hybrids showed enantioselectivities inverted toward the desired enantiomer of IPG. The acetylxylan esterase-derived variant showed an inversion in enantiomeric excess (ee) from -12.9% to +6.0%, whereas the cutinase-derived variant was improved to an ee of +26.5%. The enantioselectivity of the cutinase-derived variant was further improved by directed evolution to an ee of +57.4%.

Sensitive method for endotoxin determination in nanomedicinal product samples.

Aim: Nanomaterials and nanomedicinal products tend to interfere with various commonly used assays, including regulatory required endotoxin detection methods for medicines. We developed a method to quantify endotoxin levels that is compatible with nanomaterials and nanomedicinal products. Materials & methods: The method is based on measuring endotoxin indirectly via 3-hydroxylated fatty acids of lipid-A, using Ultra High Performance Liquid Chromatography coupled with mass spectrometry. The outcome was related to results of the commonly used Limulus Amebocyte Lysate method. Results: The ultra high performance liquid chromatography coupled with mass spectrometry method has clear advantages compared with other endotoxin determination assays; particularly the absence of nanospecific interference. Conclusion: The method is sensitive, straightforward and accurate in determining and quantifying endotoxin in nanomedicinal product samples