Biosafety in the laboratory - VIB

293 E1 and E1 deleted L2 8, e or j Recombination of
piece of E4 adenoviral sequences in the cell
genes from vector line and vector may
adenovirus
result in the
formation of
replicationcompetent
virus
particles
EBV Cells contain Not relevant L2 - Classification
immortalised complete
corresponds to that
cells EBV virus of the virus present
in the cells
* on the assumption that non-hazardous inserts are used (hazardous inserts would require a higher risk class)
** as applied in the schemes of annex 2
Laboratory requirements
The laboratory requirements may vary depending on the classification. A basic L1 laboratory
is sufficient for cells like NIH-3T3. In practice, cells like these are usually inoculated
and grown in well-equipped cell culture facilities that meet more than the basic L1 requirements.
A class II safety cabinet is usually present to protect the cells against infectious
agents when they are handled in the open. Instead of class II safety cabinets, horizontal
laminar flow cabinets are often used. The latter are suited for level 1 activities with cells
that do not involve infectious agents. They are, however, not sufficient for manipulations
with cells belonging to L2. In that case a class II safety cabinet is required to protect both
the laboratory worker, the environment and the experiment. In comparison with those of
L1, the L2 requirements are more stringent with regard to access to the laboratory and
activities that might lead to the creation of aerosols.
Waste
All the biological waste originating from genetically modified cells needs to be inactivated.
However, a distinction should be made between cells requiring L1 containment and those
requiring L2 containment. As far as L1 cell cultures are concerned, it is sufficient to expose
them to a strong detergent for a period of time and then pour it out in the sink.
Contaminated materials can be dealt with in the same manner. L2 cell cultures require
more rigorous measures, to ensure that any hazardous biological agents present in the
material are killed as well. Sterilisation is the most appropriate method to this end.
Note
Never work with autologous cells. Especially when genes encoding for growth factors or
oncogenes would be cloned into these cells, contamination could have detrimental effects.
The reason for this is that the immune system would not recognise the cells as foreign.
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Biosafety in the laboratory