tBHQ and human immune T cell activation in lab tests
What it found
In lab tests on human blood cells, tBHQ reduced the production of two immune signalling molecules and lowered markers of T cell activation.
The authors say this suggests tBHQ can dampen early T cell responses.
What they found
Animal and lab studies
Nrf2 target genes
tBHQ increased the mRNA for three Nrf2 target genes (HMOX-1, NQO1, GCLC) and slightly raised NRF2 mRNA itself in human PBMCs. This shows the tBHQ concentrations used activated Nrf2 in these cells.
IL-2 production
tBHQ lowered IL-2 protein and mRNA in activated PBMCs, and the drop was even larger in isolated CD4 T cells. Cell viability was not affected at these concentrations.
IFN-γ production
tBHQ reduced IFN-γ protein and mRNA in activated PBMCs, and the reduction was greater in isolated CD4 T cells. The authors say this shows tBHQ inhibits cytokine secretion in these human cells.
CD25 and CD69 markers
tBHQ decreased CD25 and CD69 protein on the surface of PBMCs and CD4 T cells. CD25 mRNA was also reduced in PBMCs, while CD69 mRNA showed a downward trend that was not statistically significant.
NFκB DNA binding
In PBMCs activated for 3 hours, tBHQ at 1 micromolar reduced NFκB DNA binding. The authors say this fits with tBHQ inhibiting several early events of T cell activation.
Other findings
Intake relevance
The authors note that some estimated daily intakes of tBHQ approach or exceed 100 to 150 mg, and healthy volunteers who consumed that amount had blood levels in the high micromolar range. They say this makes the concentrations used in these studies relevant to humans.
What the authors conclude
“Although these studies suggest the food additive tBHQ negatively impacts T cell activation, further studies will be needed to fully elucidate the effect of tBHQ on human immune responses.”
Also in their conclusions
- They conclude that tBHQ inhibits activation of primary human CD4 T cells, as shown by decreased cytokine production and lower CD25 and CD69 expression.
- They say further studies will be needed to fully work out the effect of tBHQ on human immune responses and host defence.
- They suggest that Nrf2 is a new regulatory pathway in primary human T cells.
How it was done
The authors wanted to find out how the food preservative tBHQ affects the early steps of T cell activation in human immune cells, because most previous work had been in rodents or lab cell lines.
They treated human peripheral blood mononuclear cells and isolated CD4 T cells with tBHQ at concentrations from 0.1 to 5 micromolar, then activated the cells with anti-CD3 and anti-CD28. They measured cytokine proteins and mRNA, cell surface markers CD25 and CD69, and NFκB DNA binding.
What it can’t tell you
- These are lab tests on human cells taken out of the body, so they cannot show what happens to the immune system in a living person.
- The study did not look at whether tBHQ affects the ability to fight off infections in people.
Who paid
- Funding
- Funded by NIEHS NIH HHS; NIGMS NIH HHS (from the PubMed record).
- Authors work at
- Michigan State University, USA
The paper
- Title
- The Nrf2 activator tBHQ inhibits T cell activation of primary human CD4 T cells
- Type
- Study
- Evidence
- Animals and lab studies
- Summarised from
- Full text
- Cite
- Turley AE, Zagorski JW, Rockwell CE (2015). The Nrf2 activator tBHQ inhibits T cell activation of primary human CD4 T cells. Cytokine. doi:10.1016/j.cyto.2014.11.006Free full textPubMed 25484350DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error