Cells Need Full Time Optimization
From a cell’s point of view in passive culture, at any one time it lives in one of four environments or states:
2. Manual Manipulation (in biosafety cabinet, glove box, lab bench, etc…)
3. Machine Processing (centrifugation, mixing, flow cytometric sorting, etc…)
4. In Transport (between states 1, 2,or 3)
There is a fifth state which is in Cryogenic Storage, which does not present the same metabolic challenges to cells as the other four states, so we will exclude that for now.
Each of these environments provides its own set of stresses upon the cell and we will go into more detail on each in following posts. However, in each state, cells are likely to be found out of optimum conditions.
Looking at the last three first,
2. Manual Manipulation
3. Machine Processing
4. In Transport
During these states, everyone knows that cells are out of optimum. We have all been taught to minimize the amount of time that cells are out of the incubator, or to try to establish incubator-like settings during these times. This is what the cells experience outside of the incubator:
Variability in cellular conditions leads to variability in cellular responses, which affects experiment-to-experiment reproducibility.
Where your cells handled exactly the same amount of time outside the incubator this week as last week? Did this person handling cells exactly the same way as that person? It is difficult to replicate these processes exactly.
This is what the cells experience when cell handling is done in a barrier isolator or glove-box like apparatus, where incubator-like conditions are maintained at all times.
Isolating cell handling from room air conditions eliminates the variability in conditions that can lead to variability in your cellular responses. You can reduce the number of repeated experiments, and reduce the wasted time, materials, and money.
Of course, everyone knows that cells are out of optimum outside of the incubator. Going back to the first state:
1. Incubation: The closest to optimal conditions in the lab for cells.
From a Peoplecentric view incubation looks like this:
However, there is a lot more going on from the cells’ point of view. Every time the incubator door is opened, room air enters, CO2 drops, and the incubator has to re-establish the CO2 levels.
Here is a more Cytocentric view of incubation:
If you simply enclose the incubator in a work space protected from room air and temperature, your cells experience this:
Enclosing the work space to control the environment also has the added bonus of added full-time protection for cells, which we explored in a previous post.
There are many non-obvious effects of oxygen variation on cells that have been documented. We will come back to the topic of oxygen control in more detail in later posts.