Background: Lysins (cell wall hydrolases) targeting gram-negative organisms require engineering to permeabilize the outer membrane and access subjacent peptidoglycan to facilitate killing. In the current study, the potential clinical utility for the engineered lysin CF-370 was examined in vitro and in vivo against gram-negative pathogens important in human infections.
Methods: Minimum inhibitory concentration (MICs) and bactericidal activity were determined using standard methods.
synergy between an antimicrobial protein lysin (cell wall hydrolase) called exebacase and each of 12 different antibiotics was examined against isolates using a nonstandard medium approved for exebacase susceptibility testing by the Clinical and Laboratory Standards Institute. In the checkerboard assay format, fractional inhibitory concentration index values of ≤0.5, consistent with synergy, were observed for the majority of interactions tested.
View Article and Find Full Text PDFAntimicrob Agents Chemother
October 2019
Exebacase, a recombinantly produced lysin (cell wall hydrolase), and comparator antibiotics were tested by the broth microdilution method against strain sets of and spp., which are the most common causes of infective endocarditis in humans. Exebacase was active against all spp.
View Article and Find Full Text PDFDevelopment of a cytomegalovirus (CMV) vaccine is a priority. We evaluated a two component alphavirus replicon particle vaccine expressing CMV gB or a pp65/IE1 fusion protein, previously shown to induce robust antibody and cellular immune responses in mice, in a randomized, double-blind Phase 1 clinical trial in CMV seronegative subjects. Forty subjects received a lower dose (LD) or higher dose (HD) of vaccine or placebo by intramuscular or subcutaneous injection at Weeks 0, 8 and 24.
View Article and Find Full Text PDFWe used a propagation-defective, single-cycle, alphavirus replicon vector system to produce virus-like replicon particles (VRP) expressing the hemagglutinin (HA) and neuraminidase (NA) proteins from influenza A/Wyoming/03/2003 (H3N2). Efficient production methods were scaled to produce pilot lots of HA VRP and NA VRP and clinical lots of HA VRP. HA VRP-induced high-titered antibody responses in mice, rabbits and rhesus macaques, as measured by ELISA or hemagglutination inhibition (HI) assays, and robust cellular immune responses in mice and rhesus macaques, as measured by IFN-gamma ELISPOT.
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