Biology subjects

Thirawatananond, P.

Publications and source records attributed to Thirawatananond, P..

2 recordsLinked to original sources

bioRxiv2023

Human immune phenotyping reveals accelerated aging in type 1 diabetes

The composition of immune cells in peripheral blood is dramatically remodeled throughout the human lifespan, as environmental exposures shape the proportion and phenotype of cellular subsets. These dynamic shifts complicate efforts to identify disease-associated immune signatures in type 1 diabetes (T1D), which is variable in age of onset and rate of {beta}-cell decline. Herein, we conducted standardized flow cytometric immune profiling on peripheral blood from a cross-sectional cohort of T1D participants (n=240), their first-degree relatives (REL, n=310), those at increased risk with two or more islet autoantibodies (RSK, n=24), and autoantibody negative healthy controls (CTR, n=252). We constructed an immune-age predictive model in healthy subjects and developed an interactive data visualization portal (ImmScape; https://ufdiabetes.shinyapps.io/ImmScape/). When applied to the T1D cohort, this model revealed accelerated immune aging (p<0.001) as well as phenotypic signatures of disease after age correction. Of 192 investigated flow cytometry and complete blood count readouts, 46 were significantly associated with age only, 25 with T1D only, and 23 with both age and T1D. Phenotypes associated with T1D after age-correction were predictive of T1D status (AUROC=82.3%). Phenotypes associated with accelerated aging in T1D included increased CXCR3+ and PD-1+ frequencies in naive and memory T cell subsets, despite reduced PD-1 expression levels (mean fluorescence intensity) on memory T cells. Additionally, quantitative trait locus analysis linked an increase in HLA-DR expression on monocytes with the T1D-associated HLA-DR4/DQ8 genotype, regardless of clinical group. Our findings demonstrate advanced immune aging in T1D and highlight disease-associated phenotypes for biomarker monitoring and therapeutic interventions. One Sentence SummaryPeripheral blood characterization reveals accelerated immune-age and age-adjusted proinflammatory immune phenotypes in type 1 diabetes.

immunology↗

bioRxiv2022

Deletion of CD226 in Foxp3+ T cells Reduces Diabetes Incidence in Non-Obese Diabetic Mice by Improving Regulatory T Cell Stability and Function

Co-stimulation serves as a critical checkpoint for T cell development and activation, and several genetic variants affecting co-stimulatory pathways confer risk for autoimmune diseases. A single nucleotide polymorphism in CD226 (rs763361; G307S) has been shown to increase susceptibility to type 1 diabetes, multiple sclerosis, and rheumatoid arthritis. CD226 competes with the co-inhibitory receptor TIGIT (T cell immunoreceptor with Ig and ITIM domains) to bind CD155 to amplify TCR signaling. We previously found that Cd226 knockout protected non-obese diabetic (NOD) mice from disease, but the impact of CD226 signaling on individual immune subsets remained unclear. We focused on regulatory T cells (Tregs) as a population of interest, as prior reports demonstrated that human CD226+ Tregs exhibit reduced FOXP3+Helios+ purity and suppressive function following expansion. Hence, we hypothesized that global deletion of Cd226 would increase Treg stability and accordingly, Treg-specific Cd226 deletion would inhibit diabetes in NOD mice. Indeed, crossing the NOD.Cd226-/- and NOD.Foxp3-GFP-Cre.R26-loxP-STOP-loxP-YFP Treg-fate tracking strains resulted in increased Treg induction and decreased FoxP3-deficient "ex-Tregs" in the pancreatic lymph nodes. We generated a Treg-conditional knockout (Treg{Delta}Cd226) strain and found that female Treg{Delta}Cd226 mice had decreased insulitis and diabetes incidence compared to TregWT mice. Additionally, we observed increased TIGIT expression on Tregs and conventional CD4+ T cells within the pancreas of Treg{Delta}Cd226 versus TregWT mice. These findings demonstrate that an imbalance of CD226/TIGIT signaling may contribute to Treg destabilization in the NOD mouse and highlight the potential for therapeutic targeting of this pathway to prevent or reverse autoimmunity.

immunology↗