KEY TAKEAWAYS
- The study aimed to investigate the role of Tregs and cytokine profiles in HAM/TSP pathogenesis.
- Researchers noticed that imbalanced IL10/TGF-β production by Tregs may worsen inflammation in patients with HAM/TSP.
Human T-cell lymphotropic virus type 1 (HTLV-1), also denominated Human T-cell leukemia virus-1 is a specific type of cancer called Adult T-cell leukemia (ATL), induces immune activation and secretion of proinflammatory cytokines, especially in individuals with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Regulatory T lymphocytes (Tregs) may control inflammation through IL10 and TGF-β.
Luana Leandro Gois and the team aimed to determine that CD4+ and CD8+ Treg frequencies in HAM/TSP, asymptomatic carriers, and uninfected individuals, and assessed cytokine profiles.
They performed an inclusive analysis by matching asymptomatic HTLV-1 carriers and HAM/TSP patients by sex and age. Frequencies of IL10- and/or TGF-β-producing Tregs were quantified using flow cytometry. Real-time RT-PCR assessed HTLV-1 proviral load and mRNA expression of cytokines and cellular receptors in peripheral blood mononuclear cells.
They observed statistically higher total frequencies of CD4+ Tregs and IL10-producing CD4+ and CD8+ Treg subsets in HAM/TSP patients compared to asymptomatic HTLV-1-infected individuals. They found a positive correlation between CD4+ IL10+ Treg frequency and HTLV-1 proviral load in HAM/TSP patients. Additionally, a positive correlation was observed between gene expression of proinflammatory and regulatory cytokines exclusively within the HAM/TSP group.
The study concluded that higher frequencies of IL10-producing Tregs in HAM/TSP patients suggest an imbalance in IL10/TGF-β production, potentially contributing to the heightened inflammatory response characteristic of the disease.
This study was supported by the Foundation for Research Support of the State of Bahia (Fapesb), by the Coordination for the Improvement of Higher Education Personnel (CAPES), financial code 001. MFRG and BG-C are research fellows of National Foundation for the Development of Private Higher Education (FUNADESP).
Source: https://pubmed.ncbi.nlm.nih.gov/38943078/
Gois LL, Ribeiro-Soares B, Regis-Silva CG, et al. (2024). “Imbalanced IL10/TGF-β production by regulatory T-lymphocytes in patients with HTLV-1-associated myelopathy/ tropical spastic paraparesis.” BMC Infect Dis. 2024 Jun 28;24(1):652. doi: 10.1186/s12879-024-09494-8. PMID: 38943078; PMCID: PMC11214226.
