Quality control

Much like typical chemical compounds, nucleic acid gene therapy agens, such as plasmids/vectors, viral particles and other, need quality control as well. Mostly it is a detection of unwanted contaminants what is needed. These contaminants originate from production systems where DNA was prepared, either from a cultivation media or as natural contaminants or from the changed original molecule.

 

Typical tests

  • Production organism residual DNA
    Plasmid DNA is frequently used in gene therapy and high purity plasmids are required. Residual DNA or proteins from the production organism (where plasmid was produced e.g. E. coli) are considered unacceptable contaminant.
  • Presence of wild type virus in artificial drug virus
    Viral vaccines or vectors are mostly prepared from wild type precursors, which lost their original activity. Artificial virus is less dangerous than wild type and has special characteristics. Wild type virus in a vaccine could have dangerous effect.
  • Correct sequence control
    To check if the sequence is free of mutant variant (insertion, deletion, changes), checking the sequence of interest is a good idea. Sanger sequencing method is a gold standard.
  • Plasmid conformation
    Stability of plasmid DNA depends on its conformation and the right conformation is required (e.g. supercoiled form).
  • Viral contaminants
    For the control of biological material it is necessary to check if the material does not contain any hazardous biological substance, such as virus.
  • Other on request

Quality Control Quality control