DR. YVONNE STAAL: Every day, we inhale airborne compounds.
Such as nanoparticles...
compounds from spraying cosmetics...
or compounds from smoking cigarettes.
When these compounds are inhaled...
they may cause local effects in the airways or they may be absorbed into our bodies.
To asses these effects, we use cell models of the airways...
cultured at the barrier between air and liquid.
That allows the cells to be exposed to compounds via the air...
in a human relevant way.
In addition, the cells have a human origin.
Which means that they can be used for human mechanistic studies.
In the future, finding a place in future risk assessment.
Airway epithelial cells can be used to study the effect of inhaled compounds.
There are two important aspects to consider.
The first one is the cell model.
Cells should be cultured at the air-liquid interface or ALI.
This allows the cells to be exposed to compounds via the air.
Which is a human relevant way of exposure.
We're using two types of cells.
Which are the epithelial lung cell layer...
and macrophages...
which is an important immune cell in the airways for particle exposure.
The second aspect is the exposure method.
To determine the effects of airborne compounds...
compounds need to be brought into the air.
The dose to which the cells are exposed is dependent...
on the concentration of the exposure...
the duration of the exposure and the frequency.
For particles, they may not always reach the cells.
It's also dependent on the deposition of the particles on the cells.
As a first site of contact macrophages and epithelial cells...
are the first to respond to a exposure...
with an inflammatory response or effects on cell barrier or cell viability.
Inflammation is a key parameter in many different diseases, such as lung fibrosis.
ALI-cultured cell models can therefore find a place in mechanism-based toxicity...
while avoiding animal studies as much as possible.
We aim to further improve the relevance and standardization of our airway models...
and their exposure...
to contribute to animal replacement...
with realistic, reliable and human relevant in vitro data.