No Plans for the Weekend, but next week is prime
Posted by Liz on April 24, 2009
I am looking forward to a nice long hot weekend, with temperature expecting to approach 90 F. I need to find some time to hunt mushrooms between moving a pile of rock & sand from a friends house and getting the pool in shape for swimming. Aside from that, I hope to have plenty of quality time in a vegetal state, absorbing vitamin D.
Next week is going to be a big one, with a number of “work related” distractions (must generate more revenue and customers), the AFCEA Frederick Golf outing on Tuesday, BioBeers on Wednesday and the Spring Research Festival at Ft Detrick on Wednesday & Thursday.
Speaking of BioBeers I am happy to announce that our speakers are all ready to roll and our sponsorship is booked!
So this makes a first, where only one of the four sponsors are actually FredCoBio companies! Just goes to show that everyone wants to be in FredCoBio! We have over 80 confirmed RSVP’s already and we’re going to have to keep attendance under 120, so if you are coming, please RSVP today! I am stunned, but not really shocked that only 16 people have signed up for the GoogleGroups page. Geesh, good thing I am not trying to do a Science 2.0 or Web 2.0 group. Looks like we’re going to have big groups from Lonza, USAMRIID and DynPort.
Enough bitching. There’s beer to be had and we have an interesting presentation by my old FITCI chums Integrated Biotherapeutics. Robert Unfer, Assistant Director Vaccine Development at IBT is going to whip the crowd into a frenzy by talking about “A Method for Decreasing Size Variability of Virus-Like Particle (VLP) Vaccine Preparations”.
Since it will be crowded at Brewers next week, I thought I’d post the abstract of the talk and a couple of figures. There will be a test and I’ve figured out that talking about really geeky science stuff is a way to keep all the Sales people at bay. Can’t keep them away, but thinning the herd every once in a while is a good thing.
A Method for Decreasing Size Variability of Virus-Like Particle (VLP) Vaccine Preparations
Background: Established and emerging pathogens present a continuous challenge to health professionals and governments. There is a need for efficacious, cost-effective, and easily produced vaccines that can provide prophylactic and possible preventative therapy for many viral infections and diseases. Virus-Like Particles (VLP) provide an excellent vehicle to deliver important antigens to the immune system, while avoiding pitfalls and problems that are associated with other live replicating vaccine delivery systems.
Methods: VLP’s consisting of the major viral structural proteins can be produced in both mammalian and insect cells, and while they may assume similar morphologies to the native virus, they are often extensively pleomorphic. This may present problems for large-scale production and purification. Since VLP’s are composed of lipid bilayer structures and have the potential to reform after disruption, Microfluidization using high shear pressures could reduce the size variability of VLP’s and ease purification. In the present work, VLP supernatant produced using insect cells was analyzed for size variability by dynamic light scattering (Horiba LB-550 DLS) and laser diffraction (Horiba LA-950 Laser Diffraction Analyzer) both prior to and after processing with the M-110Y high shear Microfluidizer. The results were compared to determine which instrument was best for analysis of the VLP size distribution. VLP’s were processed with either 2000 psi or 5000 psi, and either one or two system passes. In addition, VLP’s previously purified by standard laboratory methods were analyzed for size variability both prior to and after processing.
Results: While direct comparison of DLS and Laser Diffraction was not possible, there is strong indication that the LA-950 will provide more precise and reproducible analysis and measurement of VLP particle sizes. Pre-processed VLP’s exhibited sizes ranging from 80 nm to 1.6 uM. Optimal results were observed using 2000 psi and two system passes, and demonstrated a more narrow size range of 90 nm to 0.35 uM. Processed VLP’s were assayed for antigenicity by ELISA and Western Blot with specific antibodies. Both assays demonstrated no change in antigenicity. Immunogenicity studies in mice have also been initiated.
Conclusions: The reduction in size variability has the potential to ease VLP vaccine purification processes. And the retention of VLP antigenicity indicates that the vaccine effectiveness may not be affected. Further studies are needed including further comparison of the two methods of size analysis however; microfluidization may provide an effective method in VLP vaccine production.