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When you receive your viral vector

Your viral vector will arrive frozen, in 200ul Eperndorf tubes containing 10µl of concentrated viral vector (unless you specify in advance another size aliquot)Keep the viral vector at -80C at all times, and consider the following for each type of viral vector:

  1. Lentivirus-based vectors: very sensitive to freeze/thaw cycles, i.e. a significant drop in titer is expected after each cycle of freezing/thawing
  2. Retrovirus-based vectors: very sensitive to freeze/thaw cycles
  3. Adenovirus (AD5)-based vectors: somewhat sensitive to freeze/thaw cycles (i.e. small drop of titers following freezing/thawing cycles.)
  4. Adeno-associated virus/Self complementary adeno-associated virus vectors: can be thawed and refrozen multiple times without significant loss of titer.

We will provide you with a titer for your viral vector that is in TU (transducing units). This is the number of virions able to effectively cause expression of the viral transgene in a cell (from the particular cell line used for titration), following exposure of a near-confluent layer of these cells to a vector solution. Please keep in mind the units used for viral vector titers between different vector-producing labs are not always identical, and that the titer for a same sample can vary over several orders of magnitude depending on the titer unit used. The titer of your viral vector has been determined from a thawed sample of your vector and thus, should represent the titer to expect at the first thawing of your aliquots. When injecting your viral vector into an animal or exposing cells in culture, remember that most vectors are heat-labile: thaw the aliquots rapidly and then keep on ice until the last minute. If possible, use cold solutions and containers to dilute the samples.

Lentivirus and retrovirus-based vectors are sensitive to organic solvents like ethanol, to detergents, and should be diluted in isosmotic solutions. Ad5 and AAV vectors are resistant to ethanol and to low concentrations of Triton X-100 and other detergents, and remains integral in a wide range of osmolarities.

Always wear gloves, and decontaminate and dispose of waste appropriately (we recommend regular 5% bleach for decontamination and disposal).