Using CRISPR-Cas9 genome editing technology, we removed the Foxp3 CNS1 region in the non-obese diabetic (NOD) mouse model of spontaneous type 1 diabetes mellitus (T1D) to determine if pTregs contribute to autoimmune regulation.
Dysfunction of FOXP3-positive regulatory T cells (Tregs) likely plays a major role in the pathogenesis of multiple autoimmune diseases, including type 1 diabetes (T1D).
This loss of protection from T1D was paralleled by decreased Gr1-expressing myeloid cells and FoxP3+ Tregs and an enhanced accumulation of CD4-positive over CD8-positive T lymphocytes in pancreatic tissues.
Blood samples from 61 adult patients with type 1 diabetes and 61 sex and age-matched healthy controls were tested to count two types of Tregs, namely naturally occurring and inducible types, according to the expression of cell surface markers of CD4/CD25/CD47-FITC/PE/APC and intracellular markers of FoxP3/Helios-PE-CY5/eFlour450 by flow cytometry, respectively.We also investigated the relation between expression of such markers with HbA1c, urine albumin/creatinine ratio (UACR), and common carotid intima thickness (CIMT).
We observed higher numbers of FOXP3 Tregs, memory Tregs, erythrocytes, and lymphocytes in the cord blood from T1D pregnancies (p=0.01, p=0.002, p=0.002 and p=0.02, respectively).
Thus, we demonstrated that GAG ameliorated autoimmune T1DM by upregulating both CD4+FoxP3+ and CD8+CD122+PD-1+ Tregs while GAG synergized with CsA to further suppress autoimmunity and T1DM by reversing the decline in CD4+FoxP3+ Tregs resulted from CsA treatments.
These T1D vaccine candidates could therefore represent an expedient improvement in the challenge to induce human Foxp3(+)Tregs and to develop novel precision medicines for prevention of islet autoimmunity in children at risk of T1D.
By using biomarker discovery analysis, we found that expression of a combination of six genes, including TNFRSF1B (CD120b) and FOXP3, was significantly different between Tregs from subjects with new-onset T1D and control subjects, resulting in a sensitive (mean ± SD 0.86 ± 0.14) and specific (0.78 ± 0.18) biomarker algorithm.
The administration to patients of ex vivo-differentiated FoxP3(+) regulatory T (Treg) cells or tolerogenic dendritic cells (DCs) that promote Treg cell differentiation is considered a potential therapy for T1D; however, cell-based therapies cannot be easily translated into clinical practice.
We have previously shown that a (TC)n microsatellite in intron 5 of the Forkhead Box Protein 3 (FOXP3) gene was associated with a variant of the autoimmune polyglandular syndrome type 3 (APS3v), that is defined as the co-occurrence of type 1 diabetes (T1D) and autoimmune thyroiditis (AITD).
Moreover, type 1 diabetes reversal in preclinical models is accompanied by the selective expansion of CD4(+)Foxp3(+) T regulatory (Treg) cells, which are fundamental for the long-term maintenance of anti-CD3-mediated tolerance.
The Foxp3-E2-related suppressive activity of iT(reg) cells was altered in human autoimmune diseases, including multiple sclerosis and type 1 diabetes, and was associated with impaired glycolysis and signaling via interleukin 2.
Frequencies of CD4(+)Foxp3(+) TH17 cells were also enhanced in TT bearing girls with type 1 diabetes and correlated with the level of analyzed cytokines.
Of interestingly note, the Foxp3 promoter in FT1D patients was hypermethylated, indicating that DNA methylation could be a causative factor responsible for the reduced Foxp3 expression in FT1D patients.
The frequency of Tregs in peripheral blood was comparable but the FOXP3(+)IFN-γ(+) fraction was significantly increased in patients with type 1 diabetes compared to healthy controls.
Administration of these cytokines offers an appealing approach to manipulate the Foxp3(+)Treg pool and treat T cell-mediated autoimmunity such as type 1 diabetes.
Here, we describe a strongly agonistic insulin mimetope that effectively converts naive T cells into Foxp3(+) regulatory T cells in vivo, thereby completely preventing T1D in NOD mice.
Here, 257 single-nucleotide polymorphisms (SNPs) have been genotyped in 19 candidate genes (INS, PTPN22, IL2RA, CTLA4, IFIH1, SUMO4, VDR, PAX4, OAS1, IRS1, IL4, IL4R, IL13, IL12B, CEACAM21, CAPSL, Q7Z4c4(5Q), FOXP3, EFHB) in 2300 affected sib-pair families and tested for association with T1D as part of the Type I Diabetes Genetics Consortium's candidate gene study.