Silicon dioxide tiny particles and human immune cells in lab tests
What it found
In lab tests on human immune cells, silicon dioxide particles made the cells mature and release inflammatory signals.
The treated cells then caused other immune cells to multiply.
What they found
Animal and lab studies
Immune cell maturation
All three types of silicon dioxide particles made the human immune cells show more activation markers on their surface. This happened in lab dishes, not in people.
Inflammatory signals released
The treated human cells released more inflammatory signals into the liquid around them. Higher amounts of particles led to more signals being released in these lab tests.
Particles taken inside cells
Under a microscope, the researchers saw the silicon dioxide particles wrapped in the cell membrane and stored inside bubbles within the human cells. This was observed in lab dishes.
Other immune cells multiplied
When the treated cells were mixed with another type of human immune cell, those second cells multiplied much more than usual. This happened at every ratio tested over five days in the lab.
More T-cell signals
The mixed human cells also released more specific immune signals called IL-9, IL-17A and IL-17F. This was measured in the liquid from the lab dishes.
What the authors conclude
- They say silicon dioxide particles can push human immune cells to mature and trigger a response from other immune cells.
- They suggest these particles might play a part in how the body reacts to things in the environment when both are present at the same time.
How it was done
Silicon dioxide is widely used as a food additive and in cosmetics. The authors wanted to see if these tiny particles could act like danger signals that wake up the immune system.
They grew human immune cells from donated blood in the lab. They exposed these cells to three types of silicon dioxide particles for 16 hours. Then they mixed the treated cells with another type of human immune cell for five days to watch what happened.
What it can’t tell you
- These experiments used human cells grown in lab dishes, not whole living bodies.
- Lab dish results cannot show what happens when someone eats or touches products containing these particles.
- Scientists do not yet know if eating these particles causes this kind of immune reaction in real life.
Who paid
- Authors work at
- Université Paris-Saclay, France
The paper
- Title
- Synthetic Amorphous Silica Nanoparticles Promote Human Dendritic Cell Maturation and CD4+ T-Lymphocyte Activation
- Type
- Study
- Evidence
- Animals and lab studies
- Summarised from
- Full text
- Cite
- Feray A, Guillet É, Szely N, et al (2021). Synthetic Amorphous Silica Nanoparticles Promote Human Dendritic Cell Maturation and CD4+ T-Lymphocyte Activation. Toxicological sciences. doi:10.1093/toxsci/kfab120Free full textPubMed 34633463DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error