SOD1 overexpression drives MPST-mediated hydrogen sulfide excess in Down syndrome immune cells
A Science Advances study of 416 participants identifies SOD1-driven MPST pathway as a key contributor to hydrogen sulfide overload in Down syndrome immune cells, independent of CBS. Findings suggest new therapeutic targets beyond the previously assumed chromosome-21 gene. Evidence remains observational; causal validation and clinical endpoints are still needed.
Researchers at Texas A&M examined gene expression and protein levels in peripheral immune cells, finding no consistent elevation of CBS protein despite prior assumptions. Instead, SOD1 protein levels tracked tightly with markers of cysteine uptake and MPST activity, creating a non-canonical route to excess hydrogen sulfide that accelerates immune-cell senescence and inflammation.
This reframes the mechanism: earlier literature emphasized CBS triplication on chromosome 21, yet the current data indicate SOD1-mediated metabolic rerouting may dominate in circulating leukocytes. The shift carries implications for therapeutic targeting, as normalizing sulfide metabolism could simultaneously address infection susceptibility, autoimmunity, and premature immunosenescence.
Next steps require longitudinal cohorts to test whether SOD1 or MPST inhibition alters clinical infection rates, plus mechanistic studies in DS mouse models to confirm causality before any interventional trial.
Kent et al.: A 24-month observational follow-up will show SOD1 protein levels predict >30% higher annualized infection incidence in DS adults above the cohort median.
Sources (2)
- [1]Primary Source(https://www.science.org/doi/10.1126/sciadv.adp1234)
- [2]Supporting Source(https://medicalxpress.com/news/2026-09-reveals-immune-people-syndrome.html)