Virus Production & Purification Services

Molecular Diagnostic Services offers general laboratory services in the field of virology. These include bulk production, purification, and assay of both human and animal viruses from small research quantities to large-scale production. MDS has extensive experience in the production of a variety of human and animal viruses. Crude and purified virus can be provided either as infectious or noninfectious preparations or can be further processed by genomic isolation, viral protein analysis, or other molecular virology techniques or services. Following is the list of currently available virology services. MDS is always ready to customize protocols to your specific needs.

• Propagation of human & animal viruses (Link to Virus production page attached )
• Virus isolation
• Isolation of viral protein, RNA & DNA from infected cells
• Plaque Assay and TCID50Service
• Virus detection in cell lines (see Cell Biology Services & PCR)
• Virus expression systems (see Custom Expression Systems)
• Tittering Concentrated Virus For: Confirmation that viral stocks are viable
  • Determination of the proper transduction conditions for your particular
  • Determination of the maximum number of target cells that can be infected for a given virus volume.
  • Determining Virus Permissivity

Adenovirus & Adeno-Associated Virus (AAV) Services

Replication-deficient recombinant adenoviruses and AAVs offer an efficient way for the delivery of genes into cells. Serotype 5 adenovirus, for example, has been shown to infect most mammalian cell types including primary and transformed cell lines derived from humans, mice & rats.

In support of laboratories dedicated to the development of research tools and gene therapy, MDS has structured the following research and development services:

Construction of Recombinant Viruses High Titer Stocks

MDS offers recombinant adenovirus construction services using the AdEasy System from Stratagene or any transfer vector system of your choice as outlined below:

Adenoviruses: 

• High-titer recombinant adenoviruses in just four steps:
• Clone gene of interest into appropriate transfer vector.
• Co-transform E. coli with transfer plasmid and viral DNA to create recombinants.
• Transfect HEK 293 cells with recombinant viral DNA in order to produce recombinant adenoviruses.
• Infect Cell FactoryT to create high-titer stock--up to 3 x 1012 pfus. Purification by CsCl2 banding.
• Constructed dialized virus
• Specification sheet including:
  • yield by TCID50 assay
  • Purity by 260/280 ratio
  • Morphology by EM negative staining

AAVs: MDS offers recombinant adenovirus-associated virus construction services using the AAV Helper-Free System from Stratagene or any transfer vector system of your choice. as outlined below:

• Clone gene of interest into appropriate transfer vector
• Transfect HEK 293 cells in Cell FactoriesT with three plasmids.
• Harvest AAV virions, purify and concentrate CsCl banding
• Constructed dialized virus
• Specification sheet including:
  • yield by TCID50 assay
  • Purity by 260/280 ratio
  • Morphology by EM negative staining

Immunoassay services include:

• Vaccinia plaque and plaque reduction neutralization assays
• Residual host cell protein/residual culture or processing reagent ELISA
• DNA transfection and protein detection (ELISA and Western Blot)
• Thrombin inhibition
• TF-1 cell proliferation assays (Alamar Blue)
• MTT-based cell proliferation assays

In vitro viral assays

MDS offers QPCR assays to detect the presence of human, bovine or porcine viruses for both raw materials/additives and cell lysates. Testing of cell lysates derived from master cell banks (MCBs) and cells at the limit of in vitro cell age is strongly recommended, even if the particular MCB was produced without the use of bovine- or porcine- derived additives. Even though a cell bank can be adapted to grow without those additives, the parental cell line could have been exposed to bovine- or porcine- derived reagents or both at some point in its history.