Services :: Pilot Scale Production :: Insect Cell Culture
The use of insect cell culture for protein expression has increased dramatically over the last several decades, becoming a routine expression system for basic research and large scale commercial operations. Currently they are used commercially in the production of sub-unit vaccines, the manufacture of in vitro diagnostic materials, as well as in the manufacture of in vivo therapeutics. The ability of insect cells to produce relatively large quantities of posttranslationally modified eukaryotic proteins in a relatively short period of time has driven the acceptance of this technology.

The Baculovirus Expression Vector System
The BEVS, developed by Max Summers and Lois Miller, has unique biological advantages over bacterial, yeast or mammalian protein expression systems. A major advantage is the quick turnaround time for the expression of recombinant proteins that show biological activity, antigenicity, and immunogenicity similar to authentic natural proteins.

The Virus
The most commonly used expression system is based on the Autographa californica Nuclear Polyhedrosis Virus (AcNPV), an insect baculovirus isolated from the Alfalfa Looper. The baculovirus expression vector system has been used to express genes derived from viruses, fungi, bacteria, plants, and animals. In this system, the genes of interest are placed under the control of the polyhedrin promoter of the AcNPV.

The Cell Lines
The most widely used insect cells for BEVS are the Sf9 and Sf21 cell lines isolated from ovarian tissue of the fall army worm, Spodoptera frugiperda, and the High Five cell line, designated BTI-Tn- 5B1-4, originally established from Trichoplusia ni embryonic tissue. Sf9 or Sf21 cells are preferred for virus expansion, while any of the cell lines make excellent expression systems for production.

BEVS at Vista
Vista Biologicals’ molecular biologists can work closely with the client to clone and express full-length recombinant proteins from full-length cDNAs, EST sequence information or genomic sequences. The genes will be cloned in baculovirus vectors and expressed in insect cells. We can produce milligram amounts of recombinant protein suitable for functional screening and biological testing using a purification process that is either provided by the customer or developed in-house. Production is performed at a scale (up to 200 liters) appropriate to the needs of the client. Should the client decide to enter into clinical development, Vista can provide recombinant proteins for use in Phase I and II human clinical trials. In addition, we can prepare the necessary regulatory documents for submissions to the appropriate institutional authorities (see cGMP Support Services).