Robust associations of four new chromosome regions from genome-wide analyses of type 1 diabetes

NOD alleles at Idd1 and Idd2 loci drive exocrine pancreatic inflammation

Non-obese diabetic (NOD) mice spontaneously develop autoimmune diabetes and have enabled the identification of several loci associated with diabetes susceptibility, termed insulin-dependent diabetes (Idd). The generation of congenic mice has allowed the characterization of the impact of several loci on disease susceptibility. For instance, NOD.B6-Idd1 and B6.NOD-Idd1 congenic mice were instrumental in demonstrating that susceptibility alleles at the MHC locus (known as Idd1) are necessary but not sufficient for autoimmune diabetes progression. We previously showed that diabetes resistance alleles at the Idd2 locus provide significant protection from autoimmune diabetes onset, second to Idd1. In search of the minimal genetic factors required for T1D onset, we generated B6.Idd1.Idd2 double-congenic mice. Although the combination of Idd1 and Idd2 is not sufficient to induce diabetes onset, we observed immune infiltration in the exocrine pancreas of B6.Idd2 mice, as well as an increase in neutrophils and pancreatic tissue fibrosis. In addition, we observed phenotypic differences in T-cell subsets from B6.Idd1.Idd2 mice relative to single-congenic mice, suggesting epistatic interaction between Idd1 and Idd2 in modulating T-cell function. Altogether, these data show that Idd1 and Idd2 susceptibility alleles are not sufficient for autoimmune diabetes but contribute to inflammation and immune infiltration in the pancreas.

Immunomodulatory Functions of TNF-Related Apoptosis-Inducing Ligand in Type 1 Diabetes

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the TNF protein superfamily and was initially identified as a protein capable of inducing apoptosis in cancer cells. In addition, TRAIL can promote pro-survival and proliferation signaling in various cell types. Subsequent studies have demonstrated that TRAIL plays several important roles in immunoregulation, immunosuppression, and immune effector functions. Type 1 diabetes (T1D) is an autoimmune disease characterized by hyperglycemia due to the loss of insulin-producing β-cells, primarily driven by T-cell-mediated pancreatic islet inflammation. Various genetic, epigenetic, and environmental factors, in conjunction with the immune system, contribute to the initiation, development, and progression of T1D. Recent reports have highlighted TRAIL as an important immunomodulatory molecule with protective effects on pancreatic islets. Experimental data suggest that TRAIL protects against T1D by reducing the proliferation of diabetogenic T cells and pancreatic islet inflammation and restoring normoglycemia in animal models. In this review, we aimed to summarize the consequences of TRAIL action in T1D, focusing on and discussing its signaling mechanisms, role in the immune system, and protective effects in T1D.

Revisiting T-cell adhesion molecules as potential targets for cancer immunotherapy: CD226 and CD2

Cancer immunotherapy aims to initiate or amplify immune responses that eliminate cancer cells and create immune memory to prevent relapse. Immune checkpoint inhibitors (ICIs), which target coinhibitory receptors on immune effector cells, such as CTLA-4 and PD-(L)1, have made significant strides in cancer treatment. However, they still face challenges in achieving widespread and durable responses. The effectiveness of anticancer immunity, which is determined by the interplay of coinhibitory and costimulatory signals in tumor-infiltrating immune cells, highlights the potential of costimulatory receptors as key targets for immunotherapy. This review explores our current understanding of the functions of CD2 and CD226, placing a special emphasis on their potential as novel agonist targets for cancer immunotherapy. CD2 and CD226, which are present mainly on T and NK cells, serve important functions in cell adhesion and recognition. These molecules are now recognized for their costimulatory benefits, particularly in the context of overcoming T-cell exhaustion and boosting antitumor responses. The importance of CD226, especially in anti-TIGIT therapy, along with the CD2‒CD58 axis in overcoming resistance to ICI or chimeric antigen receptor (CAR) T-cell therapies provides valuable insights into advancing beyond the current barriers of cancer immunotherapy, underscoring their promise as targets for novel agonist therapy.

A genome-wide association study identified PTPN2 as a population-specific susceptibility gene locus for primary biliary cholangitis

BACKGROUND AND AIMS

Previous genome-wide association studies (GWAS) have indicated the involvement of shared (population-nonspecific) and nonshared (population-specific) susceptibility genes in the pathogenesis of primary biliary cholangitis (PBC) among European and East-Asian populations. Although a meta-analysis of these distinct populations has recently identified more than 20 novel PBC susceptibility loci, analyses of population-specific genetic architecture are still needed for a more comprehensive search for genetic factors in PBC.

APPROACH AND RESULTS

Protein tyrosine phosphatase nonreceptor type 2 ( PTPN2) was identified as a novel PBC susceptibility gene locus through GWAS and subsequent genome-wide meta-analysis involving 2181 cases and 2699 controls from the Japanese population (GWAS-lead variant: rs8098858, p = 2.6 × 10 -8 ). In silico and in vitro functional analyses indicated that the risk allele of rs2292758, which is a primary functional variant, decreases PTPN2 expression by disrupting Sp1 binding to the PTPN2 promoter in T follicular helper cells and plasmacytoid dendritic cells. Infiltration of PTPN2-positive T-cells and plasmacytoid dendritic cells was confirmed in the portal area of the PBC liver by immunohistochemistry. Furthermore, transcriptomic analysis of PBC-liver samples indicated the presence of a compromised negative feedback loop in vivo between PTPN2 and IFNG in patients carrying the risk allele of rs2292758.

CONCLUSIONS

PTPN2 , a novel susceptibility gene for PBC in the Japanese population, may be involved in the pathogenesis of PBC through an insufficient negative feedback loop caused by the risk allele of rs2292758 in IFN-γ signaling. This suggests that PTPN2 could be a potential molecular target for PBC treatment.

Advancing Animal Models of Human Type 1 Diabetes

Multiple rodent models have been developed to study the basis of type 1 diabetes (T1D). However, nonobese diabetic (NOD) mice and derivative strains still provide the gold standard for dissecting the basis of the autoimmune responses underlying T1D. Here, we review the developmental origins of NOD mice, and how they and derivative strains have been used over the past several decades to dissect the genetic and immunopathogenic basis of T1D. Also discussed are ways in which the immunopathogenic basis of T1D in NOD mice and humans are similar or differ. Additionally reviewed are efforts to "humanize" NOD mice and derivative strains to provide improved models to study autoimmune responses contributing to T1D in human patients.

Genetics of type-1 diabetes

Type-1 diabetes is a multifactorial disease characterized by genetic and environmental factors that contribute to its development and progression. Despite progress in the management of type-1 diabetes, the final goal of curing the disease is yet to be achieved. To establish effective methods for the prevention, intervention, and cure of the disease, the molecular mechanisms and pathways involved in its development and progression should be clarified. One effective approach is to identify genes responsible for disease susceptibility and apply information obtained from the function of genes in disease etiology for the protection, intervention, and cure of type-1 diabetes. In this review, we discuss the genetic basis of type-1 diabetes, along with prospects for its prevention, intervention, and cure for type-1 diabetes.

Immune perturbations in human pancreas lymphatic tissues prior to and after type 1 diabetes onset

Autoimmune destruction of pancreatic β cells results in type 1 diabetes (T1D), with pancreatic immune infiltrate representing a key feature in this process. Studies of human T1D immunobiology have predominantly focused on circulating immune cells in the blood, while mouse models suggest diabetogenic lymphocytes primarily reside in pancreas-draining lymph nodes (pLN). A comprehensive study of immune cells in human T1D was conducted using pancreas draining lymphatic tissues, including pLN and mesenteric lymph nodes, and the spleen from non-diabetic control, β cell autoantibody positive non-diabetic (AAb+), and T1D organ donors using complementary approaches of high parameter flow cytometry and CITEseq. Immune perturbations suggestive of a proinflammatory environment were specific for T1D pLN and AAb+ pLN. In addition, certain immune populations correlated with high T1D genetic risk independent of disease state. These datasets form an extensive resource for profiling human lymphatic tissue immune cells in the context of autoimmunity and T1D.

Haploinsufficiency in PTPN2 leads to early-onset systemic autoimmunity from Evans syndrome to lupus

An exome sequencing strategy employed to identify pathogenic variants in patients with pediatric-onset systemic lupus or Evans syndrome resulted in the discovery of six novel monoallelic mutations in PTPN2. PTPN2 is a phosphatase that acts as an essential negative regulator of the JAK/STAT pathways. All mutations led to a loss of PTPN2 regulatory function as evidenced by in vitro assays and by hyperproliferation of patients' T cells. Furthermore, patients exhibited high serum levels of inflammatory cytokines, mimicking the profile observed in individuals with gain-of-function mutations in STAT factors. Flow cytometry analysis of patients' blood cells revealed typical alterations associated with autoimmunity and all patients presented with autoantibodies. These findings further supported the notion that a loss of function in negative regulators of cytokine pathways can lead to a broad spectrum of autoimmune manifestations and that PTPN2 along with SOCS1 haploinsufficiency constitute a new group of monogenic autoimmune diseases that can benefit from targeted therapy.

Importance of Studying Non-Coding RNA in Children and Adolescents with Type 1 Diabetes

Type 1 diabetes (T1D) mellitus is a chronic illness in children and teens, with rising global incidence rates. It stems from an autoimmune attack on pancreatic β cells, leading to insufficient insulin production. Genetic susceptibility and environmental triggers initiate this process. Early detection is possible by identifying multiple autoantibodies, which aids in predicting future T1D development. A new staging system highlights T1D's onset with islet autoimmunity rather than symptoms. Family members of T1D patients face a significantly increased risk of T1D. Italy recently passed a law mandating national T1D screening for pediatric populations. Measurements of β cell function continue to be essential in assessing efficacy, and different models have been proposed, but more appropriate biomarkers are mandatory for both progression studies before the onset of diabetes and during therapeutic monitoring. Biomarkers like microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) play key roles in T1D pathogenesis by regulating gene expression. Understanding their roles offers insights into T1D mechanisms and potential therapeutic targets. In this review, we summarized recent progress in the roles of some non-coding RNAs (ncRNAs) in the pathogenesis of T1D, with particular attention to miRNAs, lncRNAs, and circRNAs.

Reduced function of the adaptor SH2B3 promotes T1D via altered gc cytokine-regulated, T cell intrinsic immune tolerance

Genome-wide association studies have identified SH2B3 as an important non-MHC gene for islet autoimmunity and type 1 diabetes (T1D). In this study, we found a single SH2B3 haplotype significantly associated with increased risk for human T1D, and this haplotype carries the single nucleotide variant rs3184504*T in SH2B3. To better characterize the role of SH2B3 in T1D, we used mouse modeling and found a T cell-intrinsic role for SH2B3 regulating peripheral tolerance. SH2B3 deficiency had minimal effect on TCR signaling or proliferation across antigen doses, yet enhanced cell survival and cytokine signaling including common gamma chain-dependent and interferon-gamma receptor signaling. SH2B3 deficient CD8+T cells showed augmented STAT5-MYC and effector-related gene expression partially reversed with blocking autocrine IL-2 in culture. Using the RIP-mOVA model, we found CD8+ T cells lacking SH2B3 promoted early islet destruction and diabetes without requiring CD4+ T cell help. SH2B3-deficient cells demonstrated increased survival post-transfer compared to control cells despite a similar proliferation profile in the same host. Next, we created a spontaneous NOD .Sh2b3 -/- mouse model and found markedly increased incidence and accelerated T1D across sexes. Collectively, these studies identify SH2B3 as a critical mediator of peripheral T cell tolerance limiting the T cell response to self-antigens.

Article Highlights

The rs3184504 polymorphism, encoding a hypomorphic variant of the negative regulator SH2B3, strongly associates with T1D.SH2B3 deficiency results in hypersensitivity to cytokines, including IL-2, in murine CD4+ and CD8+ T cells.SH2B3 deficient CD8+ T cells exhibit a comparable transcriptome to wild-type CD8+ T cells at baseline, but upon antigen stimulation SH2B3 deficient cells upregulate genes characteristic of enhanced JAK/STAT signaling and effector functions.We found a T-cell intrinsic role of SH2B3 leading to severe islet destruction in an adoptive transfer murine T1D model, while global SH2B3 deficiency accelerated spontaneous NOD diabetes across sexes.

Cracking the type 1 diabetes code: Genes, microbes, immunity, and the early life environment

Type 1 diabetes (T1D) results from a complex interplay of genetic predisposition, immunological dysregulation, and environmental triggers, that culminate in the destruction of insulin-secreting pancreatic β cells. This review provides a comprehensive examination of the multiple factors underpinning T1D pathogenesis, to elucidate key mechanisms and potential therapeutic targets. Beginning with an exploration of genetic risk factors, we dissect the roles of human leukocyte antigen (HLA) haplotypes and non-HLA gene variants associated with T1D susceptibility. Mechanistic insights gleaned from the NOD mouse model provide valuable parallels to the human disease, particularly immunological intricacies underlying β cell-directed autoimmunity. Immunological drivers of T1D pathogenesis are examined, highlighting the pivotal contributions of both effector and regulatory T cells and the multiple functions of B cells and autoantibodies in β-cell destruction. Furthermore, the impact of environmental risk factors, notably modulation of host immune development by the intestinal microbiome, is examined. Lastly, the review probes human longitudinal studies, unveiling the dynamic interplay between mucosal immunity, systemic antimicrobial antibody responses, and the trajectories of T1D development. Insights garnered from these interconnected factors pave the way for targeted interventions and the identification of biomarkers to enhance T1D management and prevention strategies.

Inefficient recruitment of DDX39B impedes pre-spliceosome assembly on FOXP3 introns

Forkhead box P3 (FOXP3) is the master fate-determining transcription factor in regulatory T (Treg) cells and is essential for their development, function, and homeostasis. Mutations in FOXP3 cause immunodysregulation polyendocrinopathy enteropathy X-linked (IPEX) syndrome, and aberrant expression of FOXP3 has been implicated in other diseases such as multiple sclerosis and cancer. We previously demonstrated that pre-mRNA splicing of FOXP3 RNAs is highly sensitive to levels of DExD-box polypeptide 39B (DDX39B), and here we investigate the mechanism of this sensitivity. FOXP3 introns have cytidine (C)-rich/uridine (U)-poor polypyrimidine (py) tracts that are responsible for their inefficient splicing and confer sensitivity to DDX39B. We show that there is a deficiency in the assembly of commitment complexes (CCs) on FOXP3 introns, which is consistent with the lower affinity of U2AF2 for C-rich/U-poor py tracts. Our data indicate an even stronger effect on the conversion of CCs to pre-spliceosomes. We propose that this is due to an altered conformation that U2AF2 adopts when it binds to C-rich/U-poor py tracts and that this conformation has a lower affinity for DDX39B. As a consequence, CCs assembled on FOXP3 introns are defective in recruiting DDX39B, and this leads to the inefficient assembly of pre-spliceosome complexes.

Blocking CD226 regulates type 2 innate lymphoid cell effector function and alleviates airway hyperreactivity

BACKGROUND

Type 2 innate lymphoid cells (ILC2s) play a pivotal role in type 2 asthma. CD226 is a costimulatory molecule involved in various inflammatory diseases.

OBJECTIVE

We aimed to investigate CD226 expression and function within human and mouse ILC2s, and to assess the impact of targeting CD226 on ILC2-mediated airway hyperreactivity (AHR).

METHODS

We administered IL-33 intranasally to wild-type mice, followed by treatment with anti-CD226 antibody or isotype control. Pulmonary ILC2s were sorted for ex vivo analyses through RNA sequencing and flow cytometry. Next, we evaluated the effects of CD226 on AHR and lung inflammation in wild-type and Rag2-/- mice. Additionally, we compared peripheral ILC2s from healthy donors and asthmatic patients to ascertain the role of CD226 in human ILC2s.

RESULTS

Our findings demonstrated an inducible expression of CD226 in activated ILC2s, enhancing their cytokine secretion and effector functions. Mechanistically, CD226 alters intracellular metabolism and enhances PI3K/AKT and MAPK signal pathways. Blocking CD226 ameliorates ILC2-dependent AHR in IL-33 and Alternaria alternata-induced models. Interestingly, CD226 is expressed and inducible in human ILC2s, and its blocking reduces cytokine production. Finally, we showed that peripheral ILC2s in asthmatic patients exhibited elevated CD226 expression compared to healthy controls.

CONCLUSION

Our findings underscore the potential of CD226 as a novel therapeutic target in ILC2s, presenting a promising avenue for ameliorating AHR and allergic asthma.

Viral infection and host immune response in diabetes

Diabetes, a chronic metabolic disorder disrupting blood sugar regulation, has emerged as a prominent silent pandemic. Uncontrolled diabetes predisposes an individual to develop fatal complications like cardiovascular disorders, kidney damage, and neuropathies and aggravates the severity of treatable infections. Escalating cases of Type 1 and Type 2 diabetes correlate with a global upswing in diabetes-linked mortality. As a growing global concern with limited preventive interventions, diabetes necessitates extensive research to mitigate its healthcare burden and assist ailing patients. An altered immune system exacerbated by chronic hyperinflammation heightens the susceptibility of diabetic individuals to microbial infections, including notable viruses like SARS-CoV-2, dengue, and influenza. Given such a scenario, we scrutinized the literature and compiled molecular pathways and signaling cascades related to immune compartments in diabetics that escalate the severity associated with the above-mentioned viral infections in them as compared to healthy individuals. The pathogenesis of these viral infections that trigger diabetes compromises both innate and adaptive immune functions and pre-existing diabetes also leads to heightened disease severity. Lastly, this review succinctly outlines available treatments for diabetics, which may hold promise as preventive or supportive measures to effectively combat these viral infections in the former.

Immunotherapeutic implications of negative regulation by protein tyrosine phosphatases in T cells: the emerging cases of PTP1B and TCPTP

In the context of inflammation, T cell activation occurs by the concerted signals of the T cell receptor (TCR), co-stimulatory receptors ligation, and a pro-inflammatory cytokine microenvironment. Fine-tuning these signals is crucial to maintain T cell homeostasis and prevent self-reactivity while offering protection against infectious diseases and cancer. Recent developments in understanding the complex crosstalk between the molecular events controlling T cell activation and the balancing regulatory cues offer novel approaches for the development of T cell-based immunotherapies. Among the complex regulatory processes, the balance between protein tyrosine kinases (PTK) and the protein tyrosine phosphatases (PTPs) controls the transcriptional and metabolic programs that determine T cell function, fate decision, and activation. In those, PTPs are de facto regulators of signaling in T cells acting for the most part as negative regulators of the canonical TCR pathway, costimulatory molecules such as CD28, and cytokine signaling. In this review, we examine the function of two close PTP homologs, PTP1B (PTPN1) and T-cell PTP (TCPTP; PTPN2), which have been recently identified as promising candidates for novel T-cell immunotherapeutic approaches. Herein, we focus on recent studies that examine the known contributions of these PTPs to T-cell development, homeostasis, and T-cell-mediated immunity. Additionally, we describe the signaling networks that underscored the ability of TCPTP and PTP1B, either individually and notably in combination, to attenuate TCR and JAK/STAT signals affecting T cell responses. Thus, we anticipate that uncovering the role of these two PTPs in T-cell biology may lead to new treatment strategies in the field of cancer immunotherapy. This review concludes by exploring the impacts and risks that pharmacological inhibition of these PTP enzymes offers as a therapeutic approach in T-cell-based immunotherapies.

Massively parallel reporter assay confirms regulatory potential of hQTLs and reveals important variants in lupus and other autoimmune diseases

We designed a massively parallel reporter assay (MPRA) in an Epstein-Barr virus transformed B cell line to directly characterize the potential for histone post-translational modifications, i.e., histone quantitative trait loci (hQTLs), expression QTLs (eQTLs), and variants on systemic lupus erythematosus (SLE) and autoimmune (AI) disease risk haplotypes to modulate regulatory activity in an allele-dependent manner. Our study demonstrates that hQTLs, as a group, are more likely to modulate regulatory activity in an MPRA compared with other variant classes tested, including a set of eQTLs previously shown to interact with hQTLs and tested AI risk variants. In addition, we nominate 17 variants (including 11 previously unreported) as putative causal variants for SLE and another 14 for various other AI diseases, prioritizing these variants for future functional studies in primary and immortalized B cells. Thus, we uncover important insights into the mechanistic relationships among genotype, epigenetics, and gene expression in SLE and AI disease phenotypes.

Prevalence of Selected Polymorphisms of Il7R, CD226, CAPSL, and CLEC16A Genes in Children and Adolescents with Autoimmune Thyroid Diseases

Hashimoto's thyroiditis (HT) and Graves' disease (GD) are common autoimmune endocrine disorders in children. Studies indicate that apart from environmental factors, genetic background significantly contributes to the development of these diseases. This study aimed to assess the prevalence of selected single-nucleotide polymorphisms (SNPs) of Il7R, CD226, CAPSL, and CLEC16A genes in children with autoimmune thyroid diseases. We analyzed SNPs at the locus rs3194051, rs6897932 of IL7R, rs763361 of CD226, rs1010601 of CAPSL, and rs725613 of CLEC16A gene in 56 HT patients, 124 GD patients, and 156 healthy children. We observed significant differences in alleles IL7R (rs6897932) between HT males and the control group (C > T, p = 0.028) and between all GD patients and healthy children (C > T, p = 0.035) as well as GD females and controls (C > T, p = 0.018). Moreover, the C/T genotype was less frequent in GD patients at rs6897932 locus and in HT males at rs1010601 locus. The presence of the T allele in the IL7R (rs6897932) locus appears to have a protective effect against HT in males and GD in all children. Similarly, the presence of the T allele in the CAPSL locus (rs1010601) seems to reduce the risk of HT development in all patients.

Genetic Variant of DNAM-1 rs763361 C>T Is Associated with Ankylosing Spondylitis in a Mexican Population

DNAM-1 (CD226) is an activating receptor expressed in CD8+ T cells, NK cells, and monocytes. It has been reported that two SNPs in the DNAM-1 gene, rs763361 C>T and rs727088 G>A, have been associated with different autoimmune diseases; however, the role of DNAM-1 in ankylosing spondylitis has been less studied. For this reason, we focused on the study of these two SNPs in association with ankylosing spondylitis. For this, 34 patients and 70 controls were analyzed using endpoint PCR with allele-specific primers. Our results suggest that rs763361 C>T is involved as a possible protective factor under the CT co-dominant model (OR = 0.34, 95% CI = 0.13-0.88, p = 0.022) and the CT + TT dominant model (OR = 0.39, 95% CI = 0.17-0.90, p = 0.025), while rs727088 G>A did not show an association with the disease in any of the inheritance models. When analyzing the relationships of the haplotypes, we found that the T + A haplotype (OR = 0.31, 95% CI = 0.13-0.73, p = 0.0083) is a protective factor for developing the disease. In conclusion, the CT and CT + TT variants of rs763361 C>T and the T + A haplotype were considered as protective factors for developing ankylosing spondylitis.

Tipping the balance in autoimmunity: are regulatory t cells the cause, the cure, or both?

Regulatory T cells (Tregs) are a specialized subgroup of T-cell lymphocytes that is crucial for maintaining immune homeostasis and preventing excessive immune responses. Depending on their differentiation route, Tregs can be subdivided into thymically derived Tregs (tTregs) and peripherally induced Tregs (pTregs), which originate from conventional T cells after extrathymic differentiation at peripheral sites. Although the regulatory attributes of tTregs and pTregs partially overlap, their modes of action, protein expression profiles, and functional stability exhibit specific characteristics unique to each subset. Over the last few years, our knowledge of Treg differentiation, maturation, plasticity, and correlations between their phenotypes and functions has increased. Genetic and functional studies in patients with numeric and functional Treg deficiencies have contributed to our mechanistic understanding of immune dysregulation and autoimmune pathologies. This review provides an overview of our current knowledge of Treg biology, discusses monogenetic Treg pathologies and explores the role of Tregs in various other autoimmune disorders. Additionally, we discuss novel approaches that explore Tregs as targets or agents of innovative treatment options.

PTPN2 Regulates Metabolic Flux to Affect β-Cell Susceptibility to Inflammatory Stress

Protein tyrosine phosphatase N2 (PTPN2) is a type 1 diabetes (T1D) candidate gene identified from human genome-wide association studies. PTPN2 is highly expressed in human and murine islets and becomes elevated upon inflammation and models of T1D, suggesting that PTPN2 may be important for β-cell survival in the context of T1D. To test whether PTPN2 contributed to β-cell dysfunction in an inflammatory environment, we generated a β-cell-specific deletion of Ptpn2 in mice (PTPN2-β knockout [βKO]). Whereas unstressed animals exhibited normal metabolic profiles, low- and high-dose streptozotocin-treated PTPN2-βKO mice displayed hyperglycemia and accelerated death, respectively. Furthermore, cytokine-treated Ptpn2-KO islets resulted in impaired glucose-stimulated insulin secretion, mitochondrial defects, and reduced glucose-induced metabolic flux, suggesting β-cells lacking Ptpn2 are more susceptible to inflammatory stress associated with T1D due to maladaptive metabolic fitness. Consistent with the phenotype, proteomic analysis identified an important metabolic enzyme, ATP-citrate lyase, as a novel PTPN2 substrate.

ARTICLE HIGHLIGHTS

Regulation of kynurenine metabolism by blood donor genetics and biology impacts red cell hemolysis in vitro and in vivo

ABSTRACT

In the field of transfusion medicine, the clinical relevance of the metabolic markers of the red blood cell (RBC) storage lesion is incompletely understood. Here, we performed metabolomics of RBC units from 643 donors enrolled in the Recipient Epidemiology and Donor Evaluation Study, REDS RBC Omics. These units were tested on storage days 10, 23, and 42 for a total of 1929 samples and also characterized for end-of-storage hemolytic propensity after oxidative and osmotic insults. Our results indicate that the metabolic markers of the storage lesion poorly correlated with hemolytic propensity. In contrast, kynurenine was not affected by storage duration and was identified as the top predictor of osmotic fragility. RBC kynurenine levels were affected by donor age and body mass index and were reproducible within the same donor across multiple donations from 2 to 12 months apart. To delve into the genetic underpinnings of kynurenine levels in stored RBCs, we thus tested kynurenine levels in stored RBCs on day 42 from 13 091 donors from the REDS RBC Omics study, a population that was also genotyped for 879 000 single nucleotide polymorphisms. Through a metabolite quantitative trait loci analysis, we identified polymorphisms in SLC7A5, ATXN2, and a series of rate-limiting enzymes (eg, kynurenine monooxygenase, indoleamine 2,3-dioxygenase, and tryptophan dioxygenase) in the kynurenine pathway as critical factors affecting RBC kynurenine levels. By interrogating a donor-recipient linkage vein-to-vein database, we then report that SLC7A5 polymorphisms are also associated with changes in hemoglobin and bilirubin levels, suggestive of in vivo hemolysis in 4470 individuals who were critically ill and receiving single-unit transfusions.

Exploring noncoding variants in genetic diseases: from detection to functional insights

Previous studies on genetic diseases predominantly focused on protein-coding variations, overlooking the vast noncoding regions in the human genome. The development of high-throughput sequencing technologies and functional genomics tools has enabled the systematic identification of functional noncoding variants. These variants can impact gene expression, regulation, and chromatin conformation, thereby contributing to disease pathogenesis. Understanding the mechanisms that underlie the impact of noncoding variants on genetic diseases is indispensable for the development of precisely targeted therapies and the implementation of personalized medicine strategies. The intricacies of noncoding regions introduce a multitude of challenges and research opportunities. In this review, we introduce a spectrum of noncoding variants involved in genetic diseases, along with research strategies and advanced technologies for their precise identification and in-depth understanding of the complexity of the noncoding genome. We will delve into the research challenges and propose potential solutions for unraveling the genetic basis of rare and complex diseases.

Gene-environment interaction in the pathophysiology of type 1 diabetes

Type 1 diabetes (T1D) is a complex metabolic autoimmune disorder that affects millions of individuals worldwide and often leads to significant comorbidities. However, the precise trigger of autoimmunity and disease onset remain incompletely elucidated. This integrative perspective article synthesizes the cumulative role of gene-environment interaction in the pathophysiology of T1D. Genetics plays a significant role in T1D susceptibility, particularly at the major histocompatibility complex (MHC) locus and cathepsin H (CTSH) locus. In addition to genetics, environmental factors such as viral infections, pesticide exposure, and changes in the gut microbiome have been associated with the development of T1D. Alterations in the gut microbiome impact mucosal integrity and immune tolerance, increasing gut permeability through molecular mimicry and modulation of the gut immune system, thereby increasing the risk of T1D potentially through the induction of autoimmunity. HLA class II haplotypes with known effects on T1D incidence may directly correlate to changes in the gut microbiome, but precisely how the genes influence changes in the gut microbiome, and how these changes provoke T1D, requires further investigations. These gene-environment interactions are hypothesized to increase susceptibility to T1D through epigenetic changes such as DNA methylation and histone modification, which in turn modify gene expression. There is a need to determine the efficacy of new interventions that target these epigenetic modifications such as "epidrugs", which will provide novel avenues for the effective management of T1D leading to improved quality of life of affected individuals and their families/caregivers.

Targeting Protein Tyrosine Phosphatases to Improve Cancer Immunotherapies

Advances in immunotherapy have brought significant therapeutic benefits to many cancer patients. Nonetheless, many cancer types are refractory to current immunotherapeutic approaches, meaning that further targets are required to increase the number of patients who benefit from these technologies. Protein tyrosine phosphatases (PTPs) have long been recognised to play a vital role in the regulation of cancer cell biology and the immune response. In this review, we summarize the evidence for both the pro-tumorigenic and tumour-suppressor function of non-receptor PTPs in cancer cells and discuss recent data showing that several of these enzymes act as intracellular immune checkpoints that suppress effective tumour immunity. We highlight new data showing that the deletion of inhibitory PTPs is a rational approach to improve the outcomes of adoptive T cell-based cancer immunotherapies and describe recent progress in the development of PTP inhibitors as anti-cancer drugs.

Identification of gene mutations associated with type 1 diabetes by next-generation sequencing in affected Palestinian families

Introduction: Diabetes Mellitus is a group of metabolic disorders characterized by hyperglycemia secondary to insulin resistance or deficiency. It is considered a major health problem worldwide. T1DM is a result of a combination of genetics, epigenetics, and environmental factors. Several genes have been associated with T1DM, including HLA, INS, CTLA4, and PTPN22. However, none of these findings have been based on linkage analysis because it is rare to find families with several diabetic individuals. Two Palestinian families with several afflicted members with variations in the mode of inheritance were identified and selected for this study. This study aimed to identify the putative causative gene(s) responsible for T1DM development in these families to improve our understanding of the molecular genetics of the disease. Methods: One afflicted member from each family was selected for Whole-Exome Sequencing. Data were mapped to the reference of the human genome, and the resulting VCF file data were filtered. The variants with the highest phenotype correlation score were checked by Sanger sequencing for all family members. The confirmed variants were analyzed in silico by bioinformatics tools. Results: In one family, the IGF1R p.V579F variant, which follows autosomal dominant inheritance, was confirmed and segregated in the family. In another family, the NEUROD1 p.P197H variant, which follows autosomal recessive inheritance, was positively confirmed and segregated. Conclusion: IGF1R p.V579F and NEUROD1 p.P197H variants were associated with T1DM development in the two inflicted families. Further analysis and functional assays will be performed, including the generation of mutant model cell systems, to unravel their specific molecular mechanism in the disease development.

Identification of a prognostic signature based on five ferroptosis-related genes for diffuse large B-cell lymphoma

BACKGROUND

Therapies for diffuse large B-cell lymphoma (DLBCL) are limited due to the diverse gene expression profiles and complicated immune microenvironments, making it an aggressive lymphoma. Beyond this, researches have shown that ferroptosis contributes to tumorigenesis, progression, and metastasis. We thus are interested to dissect the connection between ferroptosis and disease status of DLBCL. We aim at generating a valuable prognosis gene signature for predicting the status of patients of DLBCL, with focus on ferroptosis-related genes (FRGs).

OBJECTIVE

To examine the connection between ferroptosis-related genes (FRGs) and clinical outcomes in DLBCL patients based on public datasets.

METHODS

An expression profile dataset for DLBCL was downloaded from GSE32918 (https://www.ncbi.nlm.nih.gov/geo/ query/acc.cgi?acc=gse32918), and a ferroptosis-related gene cluster was obtained from the FerrDb database (http://www. zhounan.org/ferrdb/). A prognostic signature was developed from this gene cluster by applying a least absolute shrinkage and selection operator (LASSO) Cox regression analysis to GSE32918, followed by external validation. Its effectiveness as a biomarker and the prognostic value was determined by a receiver operator characteristic curve mono factor analysis. Finally, functional enrichment was evaluated by the package Cluster Profiler of R.

RESULTS

Five ferroptosis-related genes (FRGs) (GOP1, GPX2, SLC7A5, ATF4, and CXCL2) associated with DLBCL were obtained by a multivariate analysis. The prognostic power of these five FRGs was verified by TCGA (https://xenabrowser.net/datapages/?dataset=TCGA.DLBC.sampleMap%2FHiSeqV2_PANCAN&host=https%3A%2F%2Ftcga.xenahubs.net&removeHub=https%3A%2F%2Fxena.treehouse.gi.ucsc.edu%3A44) and GEO (https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=gse 32918) datasets, with ROC analyses. KEGG and GO analyses revealed that upregulated genes in the high-risk group based on the gene signature were enriched in receptor interactions and other cancer-related pathways, including pathways related to abnormal metabolism and cell differentiation.

CONCLUSION

The newly developed signature involving GOP1, GPX2, SLC7A5, ATF4, and CXCL2 has the potential to serve as a prognostic biomarker. Furthermore, our results provide additional support for the contribution of ferroptosis to DLBCL.

Association of RPS26 gene polymorphism with different types of diabetes in Chinese individuals

AIMS/INTRODUCTION

Different types of diabetes show distinct genetic characteristics, but the specific genetic susceptibility factors remain unclear. Our study aimed to explore the associations between the ribosomal protein S26 (RPS26) gene rs1131017 polymorphisms and susceptibility to type 1 diabetes mellitus, latent autoimmune diabetes in adults (LADA) and type 2 diabetes mellitus in the Chinese Han population, and their correlations with clinical features.

MATERIALS AND METHODS

Genotyping of the rs1131017 variant was carried out for 1,006 type 1 diabetes mellitus patients, 210 LADA patients, 642 type 2 diabetes mellitus patients and 2,099 control individuals.

RESULTS

We found that the rs1131017 C allele was a risk locus for both type 1 diabetes mellitus and LADA (odds ratio [OR] 1.50, 95% confidence interval [CI] 1.33-1.69, P < 0.001; OR 1.31, 95% CI 1.04-1.64, P = 0.021, respectively). Nevertheless, this association was not found for type 2 diabetes mellitus. Carrying the C allele genotype was associated with a lower postprandial C-peptide for type 1 diabetes mellitus (OR 1.41, 95% CI 1.11-1.80, P = 0.006) and lower fasting C-peptide for LADA (OR 1.55, 95% CI 1.01-2.38, P = 0.047). Interestingly, a lower GC frequency was noted for LADA than for type 1 diabetes mellitus, regardless of classification based on age at diagnosis, C-peptide or glutamic acid decarboxylase antibody positivity.

CONCLUSIONS

The RPS26 polymorphism was associated with susceptibility and clinical characteristics of type 1 diabetes mellitus and LADA in the Chinese population, but was not related to type 2 diabetes mellitus. Thus, it might serve as a novel biomarker for particular types of diabetes.

SOCS-JAK-STAT inhibitors and SOCS mimetics as treatment options for autoimmune uveitis, psoriasis, lupus, and autoimmune encephalitis

Autoimmune diseases arise from atypical immune responses that attack self-tissue epitopes, and their development is intricately connected to the disruption of the JAK-STAT signaling pathway, where SOCS proteins play crucial roles. Conditions such as autoimmune uveitis, psoriasis, lupus, and autoimmune encephalitis exhibit immune system dysfunctions associated with JAK-STAT signaling dysregulation. Emerging therapeutic strategies utilize JAK-STAT inhibitors and SOCS mimetics to modulate immune responses and alleviate autoimmune manifestations. Although more research and clinical studies are required to assess their effectiveness, safety profiles, and potential for personalized therapeutic approaches in autoimmune conditions, JAK-STAT inhibitors and SOCS mimetics show promise as potential treatment options. This review explores the action, effectiveness, safety profiles, and future prospects of JAK inhibitors and SOCS mimetics as therapeutic agents for psoriasis, autoimmune uveitis, systemic lupus erythematosus, and autoimmune encephalitis. The findings underscore the importance of investigating these targeted therapies to advance treatment options for individuals suffering from autoimmune diseases.

Interleukin-15 cytokine checkpoints in natural killer cell anti-tumor immunity

Over recent years, the use of immune checkpoint inhibitors (ICI) has progressed to first and second-line treatments in several cancer types, transforming patient outcomes. While these treatments target T cell checkpoints, such as PD-1, LAG3 and CTLA-4, their efficacy can be compromised through adaptive resistance whereby tumors acquire mutations in genes regulating neoantigen presentation by MHC-I [93]. ICI-responsive tumor types such as advanced metastatic melanoma typically have a high mutational burden and immune infiltration; however, most patients still do not benefit from ICI monotherapy for a number of reasons [94]. This highlights the need for novel immunotherapy strategies that evoke the immune control of tumor cells with low neoantigen/MHC-I expression, overcome immune suppressive tumor microenvironments and promote tumor inflammation. In this regard, targeting natural killer (NK) cells may offer a solution to some of these bottlenecks.

Combining polygenic risk scores and human leukocyte antigen variants for personalized risk assessment of type 1 diabetes in the Taiwanese population

AIMS

To analyse the genome-wide association study (GWAS) data of patients with type 1 diabetes mellitus (T1D) in order to develop a risk score for the genetic effects on T1D risk and age at diagnosis in the Taiwanese population.

MATERIALS AND METHODS

We selected 610 patients with T1D and 2511 healthy individuals from an electronic medical record database of more than 300 000 individuals with genetic information, analysed their GWAS data, and developed a polygenic risk score (PRS).

RESULTS

The PRS, based on 149 selected single-nucleotide polymorphisms, could effectively predict T1D risk. A PRS increase was associated with increased T1D risk (odds ratio [OR] 2.09, 95% confidence interval [CI] 1.72-2.55). Moreover, a 1-unit increase in standardized T1D PRS decreased the age at diagnosis by 0.74 years. Combined PRS and human leukocyte antigen (HLA) DQA1*03:02-DQA1*05:01 genotypes could accurately predict T1D risk. In multivariable models, HLA variants and PRS were independent risk factors for T1D risk (OR 3.76 [95% CI 1.54-9.16] and 1.71 [95% CI 1.37-2.13] for HLA DQA1*03:02-DQA1*05:01 and PRS, respectively). In a limited study population of those aged ≤18 years, PRS remained significantly associated with T1D risk. The association between T1D PRS and age at diagnosis was more obvious among males and patients aged ≤18 years.

CONCLUSIONS

Polygenic risk score and HLA variations enable personalized risk estimates, enhance newborn screening efficiency for ketoacidosis prevention, and addresses the gap in data on T1D prediction in isolated Asian populations.

Guidelines and Recommendations for Laboratory Analysis in the Diagnosis and Management of Diabetes Mellitus

BACKGROUND

Numerous laboratory tests are used in the diagnosis and management of diabetes mellitus. The quality of the scientific evidence supporting the use of these assays varies substantially.

APPROACH

An expert committee compiled evidence-based recommendations for laboratory analysis in screening, diagnosis, or monitoring of diabetes. The overall quality of the evidence and the strength of the recommendations were evaluated. The draft consensus recommendations were evaluated by invited reviewers and presented for public comment. Suggestions were incorporated as deemed appropriate by the authors (see Acknowledgments). The guidelines were reviewed by the Evidence Based Laboratory Medicine Committee and the Board of Directors of the American Association for Clinical Chemistry and by the Professional Practice Committee of the American Diabetes Association.

CONTENT

Diabetes can be diagnosed by demonstrating increased concentrations of glucose in venous plasma or increased hemoglobin A1c (HbA1c) in the blood. Glycemic control is monitored by the people with diabetes measuring their own blood glucose with meters and/or with continuous interstitial glucose monitoring (CGM) devices and also by laboratory analysis of HbA1c. The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of ketones, autoantibodies, urine albumin, insulin, proinsulin, and C-peptide are addressed.

SUMMARY

The guidelines provide specific recommendations based on published data or derived from expert consensus. Several analytes are found to have minimal clinical value at the present time, and measurement of them is not recommended.

Germline mechanisms of immunotherapy toxicities in the era of genome-wide association studies

Cancer immunotherapy has revolutionized the treatment of advanced cancers and is quickly becoming an option for early-stage disease. By reactivating the host immune system, immunotherapy harnesses patients' innate defenses to eradicate the tumor. By putatively similar mechanisms, immunotherapy can also substantially increase the risk of toxicities or immune-related adverse events (irAEs). Severe irAEs can lead to hospitalization, treatment discontinuation, lifelong immune complications, or even death. Many irAEs present with similar symptoms to heritable autoimmune diseases, suggesting that germline genetics may contribute to their onset. Recently, genome-wide association studies (GWAS) of irAEs have identified common germline associations and putative mechanisms, lending support to this hypothesis. A wide range of well-established GWAS methods can potentially be harnessed to understand the etiology of irAEs specifically and immunotherapy outcomes broadly. This review summarizes current findings regarding germline effects on immunotherapy outcomes and discusses opportunities and challenges for leveraging germline genetics to understand, predict, and treat irAEs.

Regulatory T cells in autoimmune kidney diseases and transplantation

Regulatory T (Treg) cells that express the transcription factor forkhead box protein P3 (FOXP3) are naturally present in the immune system and have roles in the maintenance of immunological self-tolerance and immune system and tissue homeostasis. Treg cells suppress T cell activation, expansion and effector functions by various mechanisms, particularly by controlling the functions of antigen-presenting cells. They can also contribute to tissue repair by suppressing inflammation and facilitating tissue regeneration, for example, via the production of growth factors and the promotion of stem cell differentiation and proliferation. Monogenic anomalies of Treg cells and genetic variations of Treg cell functional molecules can cause or predispose patients to the development of autoimmune diseases and other inflammatory disorders, including kidney diseases. Treg cells can potentially be utilized or targeted to treat immunological diseases and establish transplantation tolerance, for example, by expanding natural Treg cells in vivo using IL-2 or small molecules or by expanding them in vitro for adoptive Treg cell therapy. Efforts are also being made to convert antigen-specific conventional T cells into Treg cells and to generate chimeric antigen receptor Treg cells from natural Treg cells for adoptive Treg cell therapies with the aim of achieving antigen-specific immune suppression and tolerance in the clinic.

Massively Parallel Reporter Assay Confirms Regulatory Potential of hQTLs and Reveals Important Variants in Lupus and Other Autoimmune Diseases

Objective

To systematically characterize the potential for histone post-translational modifications, i.e., histone quantitative trait loci (hQTLs), expression QTLs (eQTLs), and variants on systemic lupus erythematosus (SLE) and autoimmune (AI) disease risk haplotypes to modulate gene expression in an allele dependent manner.

Methods

We designed a massively parallel reporter assay (MPRA) containing ~32K variants and transfected it into an Epstein-Barr virus transformed B cell line generated from an SLE case.

Results

Our study expands our understanding of hQTLs, illustrating that epigenetic QTLs are more likely to contribute to functional mechanisms than eQTLs and other variant types, and a large proportion of hQTLs overlap transcription start sites (TSS) of noncoding RNAs. In addition, we nominate 17 variants (including 11 novel) as putative causal variants for SLE and another 14 for various other AI diseases, prioritizing these variants for future functional studies primary and immortalized B cells.

Conclusion

We uncover important insights into the mechanistic relationships between genotype, epigenetics, gene expression, and SLE and AI disease phenotypes.

DNMT3B activates FGFR3-mediated endoplasmic reticulum stress by regulating PTPN2 promoter methylation to promote the development of atherosclerosis

Endoplasmic reticulum (ER) stress is closely associated with atherosclerosis (AS). Nevertheless, the regulatory mechanism of ER stress in endothelial cells during AS progression is unclear. Here, the role and regulatory mechanism of DNA (cytosine-5-)- methyltransferase 3 beta (DNMT3B) in ER stress during AS progression were investigated. ApoE^-/- mice were fed with high fat diet to construct AS model in vivo. HE and Masson staining were performed to analyze histopathological changes and collagen deposition. HUVECs stimulated by ox-LDL were used as AS cellular model. Cell apoptosis was examined using flow cytometry. DCFH-DA staining was performed to examine ROS level. The levels of pro-inflammatory cytokines were assessed using ELISA. In addition, MSP was employed to detect PTPN2 promoter methylation level. Our results revealed that DNMT3B and FGFR3 were significantly upregulated in AS patient tissues, whereas PTPN2 was downregulated. PTPN2 overexpression attenuate ox-LDL-induced ER stress, inflammation and apoptosis in HUVECs and ameliorated AS symptoms in vivo. PTPN2 could suppress FGFR3 expression in ox-LDL-treated HUVECs, and FGFR3 knockdown inhibited ER stress to attenuate ox-LDL-induced endothelial cell apoptosis. DNMT3B could negatively regulate PTPN2 expression and positively FGFR2 expression in ox-LDL-treated HUVECs; DNMT3B activated FGFR2 expression by increasing PTPN2 promoter methylation level. DNMT3B downregulation repressed ox-LDL-induced ER stress, inflammation and cell apoptosis in endothelial cells, which was reversed by PTPN2 silencing. DNMT3B activated FGFR3-mediated ER stress by increasing PTPN2 promoter methylation level and suppressed its expression, thereby boosting ER stress to facilitate AS progression.

A small molecule inhibitor of PTP1B and PTPN2 enhances T cell anti-tumor immunity

The inhibition of protein tyrosine phosphatases 1B (PTP1B) and N2 (PTPN2) has emerged as an exciting approach for bolstering T cell anti-tumor immunity. ABBV-CLS-484 is a PTP1B/PTPN2 inhibitor in clinical trials for solid tumors. Here we have explored the therapeutic potential of a related small-molecule-inhibitor, Compound-182. We demonstrate that Compound-182 is a highly potent and selective active site competitive inhibitor of PTP1B and PTPN2 that enhances T cell recruitment and activation and represses the growth of tumors in mice, without promoting overt immune-related toxicities. The enhanced anti-tumor immunity in immunogenic tumors can be ascribed to the inhibition of PTP1B/PTPN2 in T cells, whereas in cold tumors, Compound-182 elicited direct effects on both tumor cells and T cells. Importantly, treatment with Compound-182 rendered otherwise resistant tumors sensitive to α-PD-1 therapy. Our findings establish the potential for small molecule inhibitors of PTP1B and PTPN2 to enhance anti-tumor immunity and combat cancer.

Guidelines and Recommendations for Laboratory Analysis in the Diagnosis and Management of Diabetes Mellitus

BACKGROUND

Numerous laboratory tests are used in the diagnosis and management of diabetes mellitus. The quality of the scientific evidence supporting the use of these assays varies substantially.

APPROACH

An expert committee compiled evidence-based recommendations for laboratory analysis in screening, diagnosis, or monitoring of diabetes. The overall quality of the evidence and the strength of the recommendations were evaluated. The draft consensus recommendations were evaluated by invited reviewers and presented for public comment. Suggestions were incorporated as deemed appropriate by the authors (see Acknowledgments). The guidelines were reviewed by the Evidence Based Laboratory Medicine Committee and the Board of Directors of the American Association of Clinical Chemistry and by the Professional Practice Committee of the American Diabetes Association.

CONTENT

Diabetes can be diagnosed by demonstrating increased concentrations of glucose in venous plasma or increased hemoglobin A1c (Hb A1c) in the blood. Glycemic control is monitored by the people with diabetes measuring their own blood glucose with meters and/or with continuous interstitial glucose monitoring (CGM) devices and also by laboratory analysis of Hb A1c. The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of ketones, autoantibodies, urine albumin, insulin, proinsulin, and C-peptide are addressed.

SUMMARY

The guidelines provide specific recommendations based on published data or derived from expert consensus. Several analytes are found to have minimal clinical value at the present time, and measurement of them is not recommended.

A small molecule inhibitor of PTP1B and PTPN2 enhances T cell anti-tumor immunity

The inhibition of protein tyrosine phosphatases (PTPs), such as PTP1B and PTPN2 that function as intracellular checkpoints, has emerged as an exciting new approach for bolstering T cell anti-tumor immunity to combat cancer. ABBV-CLS-484 is a dual PTP1B and PTPN2 inhibitor currently in clinical trials for solid tumors. Here we have explored the therapeutic potential of targeting PTP1B and PTPN2 with a related small molecule inhibitor, Compound 182. We demonstrate that Compound 182 is a highly potent and selective active site competitive inhibitor of PTP1B and PTPN2 that enhances antigen-induced T cell activation and expansion ex vivo and represses the growth of syngeneic tumors in C57BL/6 mice without promoting overt immune-related toxicities. Compound 182 repressed the growth of immunogenic MC38 colorectal and AT3-OVA mammary tumors as well as immunologically cold AT3 mammary tumors that are largely devoid of T cells. Treatment with Compound 182 increased both the infiltration and activation of T cells, as well as the recruitment of NK cells and B cells that promote anti-tumor immunity. The enhanced anti-tumor immunity in immunogenic AT3-OVA tumors could be ascribed largely to the inhibition of PTP1B/PTPN2 in T cells, whereas in cold AT3 tumors, Compound 182 elicited both direct effects on tumor cells and T cells to facilitate T cell recruitment and thereon activation. Importantly, treatment with Compound 182 rendered otherwise resistant AT3 tumors sensitive to anti-PD1 therapy. Our findings establish the potential for small molecule active site inhibitors of PTP1B and PTPN2 to enhance anti-tumor immunity and combat cancer.

Association of the rs1990760, rs3747517, and rs10930046 polymorphisms in the IFIH1 gene with susceptibility to autoimmune diseases: a meta-analysis

Objective

Interferon induced with helicase C domain 1 (IFIH1) single-nucleotide polymorphisms (SNP) rs1990760, rs3747517, and rs10930046 have been shown to be closely related to the risk of autoimmune diseases. The aim of this study was firstly to examine the association of the rs1990760 with type 1 diabetes (T1D) in a Chinese population. Secondly, to assess the association of SNP rs1990760, rs3747517, and rs10930046 with autoimmune diseases susceptibility.

Methods

A total of 1,273 T1D patients and 1,010 healthy control subjects in a Chinese population were enrolled in this case-control study. Subsequently, we performed a meta-analysis on the association of the SNP rs1990760, rs3747517, and rs10930046 in the IFIH1 gene with susceptibility to autoimmune diseases. The random and fixed genetic effects models were used to evaluate the association and the effect sizes, including odds ratios (OR) and 95% confidence intervals (CI). Stratification analyses based on ethnicity and the type of autoimmune diseases were performed.

Results

IFIH1 SNP rs1990760 was not associated with a significant risk of T1D in the Chinese population in the case-control study. A total of 35 studies including 70,966 patients and 124,509 controls were identified and included in the meta-analysis. The results displayed significant associations between IFIH1 rs1990760 A allele and rs3747517 C allele and autoimmune diseases risk (OR=1.09, 95% CI: 1.01~1.17; OR=1.24, 95% CI: 1.15~1.25, respectively). Stratified analysis indicated a significant association rs1990760 and rs3747517 with autoimmune diseases risk in the Caucasian population (OR=1.11, 95% CI: 1.02~1.20, OR=1.29, 95% CI: 1.18~1.41, respectively).

Conclusions

This study revealed no association between IFIH1 SNP rs1990760 and T1D in Chinese. Furthermore, the meta-analysis indicated that rs1990760 and rs3747517 polymorphisms, confer susceptibility to autoimmune diseases, especially in the Caucasian population.

Non-coding sequence variation reveals fragility within interleukin 2 feedback circuitry and shapes autoimmune disease risk

Genetic variants associated with human autoimmune diseases commonly map to non-coding control regions, particularly enhancers that function selectively in immune cells and fine-tune gene expression within a relatively narrow range of values. How such modest, cell-type-selective changes can meaningfully shape organismal disease risk remains unclear. To explore this issue, we experimentally manipulated species-conserved enhancers within the disease-associated IL2RA locus and studied accompanying changes in the progression of autoimmunity. Perturbing distinct enhancers with restricted activity in conventional T cells (Tconvs) or regulatory T cells (Tregs)-two functionally antagonistic T cell subsets-caused only modest, cell-type-selective decreases in IL2ra expression parameters. However, these same perturbations had striking and opposing effects in vivo , completely preventing or severely accelerating disease in a murine model of type 1 diabetes. Quantitative tissue imaging and computational modelling revealed that each enhancer manipulation impinged on distinct IL-2-dependent feedback circuits. These imbalances altered the intracellular signaling and intercellular communication dynamics of activated Tregs and Tconvs, producing opposing spatial domains that amplified or constrained ongoing autoimmune responses. These findings demonstrate how subtle changes in gene regulation stemming from non-coding variation can propagate across biological scales due to non-linearities in intra- and intercellular feedback circuitry, dramatically shaping disease risk at the organismal level.

Genome-wide aggregated trans-effects on risk of type 1 diabetes: A test of the "omnigenic" sparse effector hypothesis of complex trait genetics

The "omnigenic" hypothesis postulates that the polygenic effects of common SNPs on a typical complex trait are mediated through trans-effects on expression of a relatively sparse set of effector ("core") genes. We tested this hypothesis in a study of 4,964 cases of type 1 diabetes (T1D) and 7,497 controls by using summary statistics to calculate aggregated (excluding the HLA region) trans-scores for gene expression in blood. From associations of T1D with aggregated trans-scores, nine putative core genes were identified, of which three-STAT1, CTLA4 and FOXP3-are genes in which variants cause monogenic forms of autoimmune diabetes. Seven of these genes affect the activity of regulatory T cells, and two are involved in immune responses to microbial lipids. Four T1D-associated genomic regions could be identified as master regulators via trans-effects on gene expression. These results support the sparse effector hypothesis and reshape our understanding of the genetic architecture of T1D.

Genetic and epigenetic background of diabetic kidney disease

Diabetic kidney disease (DKD) is a severe diabetic complication that affects up to half of the individuals with diabetes. Elevated blood glucose levels are a key underlying cause of DKD, but DKD is a complex multifactorial disease, which takes years to develop. Family studies have shown that inherited factors also contribute to the risk of the disease. During the last decade, genome-wide association studies (GWASs) have emerged as a powerful tool to identify genetic risk factors for DKD. In recent years, the GWASs have acquired larger number of participants, leading to increased statistical power to detect more genetic risk factors. In addition, whole-exome and whole-genome sequencing studies are emerging, aiming to identify rare genetic risk factors for DKD, as well as epigenome-wide association studies, investigating DNA methylation in relation to DKD. This article aims to review the identified genetic and epigenetic risk factors for DKD.

Genetic improvement of economic traits in Murrah buffalo using significant SNPs from genome-wide association study

GWAS helps to identify QTL and candidate genes of specific traits. Buffalo breeding has primarily focused on milk production, but its negative correlation with reproduction traits resulted in unfavorable decline of reproductive performance among buffaloes. A genome wide scan was performed on a total of 120 Murrah buffaloes genotyped by ddRAD sequencing for 13 traits related to female fertility, production, and growth. The identified 25 significant single nucleotide polymorphisms (SNPs) (P <1×10⁶) are associated with age at first calving (AFC), age at first service (AFS), period from calving to 1^st Artifical Insemination (AI), service period (SP) and 6 month body weight (6M). Fifteen genetic variants overlapped with different QTL regions of reported studies. Among the associated loci, outstanding candidate genes for fertility, including AQP1, TRNAE-CUC, NRIP1, CPNE4, and VOPP1, have effect in different fertility traits. AQP1 gene is expressed in ovulatory phase and various stages of pregnancy. TRNAE-CUC gene is associated with AFC and number . of calvings after 4 years of age. Glycogen content-associated gene CPNE4 regulates muscle glycogen and is upregulated during early pregnancy. NRIP1 generegulates ovulation, corpus luteum at pregnancy, and mammary gland development. The objective is to identify potential genomic regions and genetic variants associated with economic traits and to select the most significant SNP which have positive effect on all the traits.

CLEC16A-An Emerging Master Regulator of Autoimmunity and Neurodegeneration

CLEC16A is emerging as an important genetic risk factor for several autoimmune disorders and for Parkinson disease (PD), opening new avenues for translational research and therapeutic development. While the exact role of CLEC16A in health and disease is still being elucidated, the gene plays a critical role in the regulation of autophagy, mitophagy, endocytosis, intracellular trafficking, immune function, and in biological processes such as insulin secretion and others that are important to cellular homeostasis. As shown in both human and animal modeling studies, CLEC16A hypofunction predisposes to both autoinflammatory phenotype and neurodegeneration. While the two are clearly related, further functional studies are needed to fully understand the mechanisms involved for optimized therapeutic interventions. Based on recent data, mitophagy-inducing drugs may be warranted, and such therapy should be tested in clinical trials as these drugs would tackle the underlying pathogenic mechanism (s) and could treat or prevent symptoms of autoimmunity and neurodegeneration in individuals with CLEC16A risk variants. Accordingly, interventions directed at reversing the dysregulated mitophagy and the consequences of loss of function of CLEC16A without activating other detrimental cellular pathways could present an effective therapy. This review presents the emerging role of CLEC16A in health and disease and provides an update on the disease processes that are attributed to variants located in the CLEC16A gene, which are responsible for autoimmune disorders and neurodegeneration with emphasis on how this information is being translated into practical and effective applications in the clinic.

PTPN22 R620W gene editing in T cells enhances low-avidity TCR responses

A genetic variant in the gene PTPN22 (R620W, rs2476601) is strongly associated with increased risk for multiple autoimmune diseases and linked to altered TCR regulation and T cell activation. Here, we utilize Crispr/Cas9 gene editing with donor DNA repair templates in human cord blood-derived, naive T cells to generate PTPN22 risk edited (620W), non-risk edited (620R), or knockout T cells from the same donor. PTPN22 risk edited cells exhibited increased activation marker expression following non-specific TCR engagement, findings that mimicked PTPN22 KO cells. Next, using lentiviral delivery of T1D patient-derived TCRs against the pancreatic autoantigen, islet-specific glucose-6 phosphatase catalytic subunit-related protein (IGRP), we demonstrate that loss of PTPN22 function led to enhanced signaling in T cells expressing a lower avidity self-reactive TCR, but not a high-avidity TCR. In this setting, loss of PTPN22 mediated enhanced proliferation and Th1 skewing. Importantly, expression of the risk variant in association with a lower avidity TCR also increased proliferation relative to PTPN22 non-risk T cells. Together, these findings suggest that, in primary human T cells, PTPN22 rs2476601 contributes to autoimmunity risk by permitting increased TCR signaling and activation in mildly self-reactive T cells, thereby potentially expanding the self-reactive T cell pool and skewing this population toward an inflammatory phenotype.

IL-2-based approaches to Treg enhancement

Immune homeostasis is heavily dependent on the action of regulatory T cells (Tregs) which act to suppress the activation of many immune cell types including autoreactive conventional T cells. A body of evidence has shown that Tregs are intrinsically defective in many common autoimmune diseases, and gene polymorphisms which increase the susceptibility of autoimmune disease development have implicated the interleukin-2 (IL-2) signaling pathway as a key dysregulated mechanism. IL-2 is essential for Treg function and survival, and Tregs are highly sensitive to low levels of this cytokine in their environment. This review will revisit the rationale behind using low-dose IL-2 as a therapy to treat autoimmune diseases and evaluate the outcomes of trials to date. Furthermore, novel engineered IL-2 therapies with increased Treg specificity have shown promise in pre-clinical studies and human clinical trials for some agents have begun. Future studies will determine whether low-dose IL-2 or engineered IL-2 therapies can change the course of autoimmune and inflammatory diseases in patients.

PTPN2 regulates bacterial clearance in a mouse model of enteropathogenic and enterohemorrhagic E. coli infection

Macrophages intimately interact with intestinal epithelial cells, but the consequences of defective macrophage-epithelial cell interactions for protection against enteric pathogens are poorly understood. Here, we show that in mice with a deletion in protein tyrosine phosphatase nonreceptor type 2 (PTPN2) in macrophages, infection with Citrobacter rodentium, a model of enteropathogenic and enterohemorrhagic E. coli infection in humans, promoted a strong type 1/IL-22-driven immune response, culminating in accelerated disease but also faster clearance of the pathogen. In contrast, deletion of PTPN2 specifically in epithelial cells rendered the epithelium unable to upregulate antimicrobial peptides and consequently resulted in a failure to eliminate the infection. The ability of PTPN2-deficient macrophages to induce faster recovery from C. rodentium was dependent on macrophage-intrinsic IL-22 production, which was highly increased in macrophages deficient in PTPN2. Our findings demonstrate the importance of macrophage-mediated factors, and especially macrophage-derived IL-22, for the induction of protective immune responses in the intestinal epithelium, and show that normal PTPN2 expression in the epithelium is crucial to allow for protection against enterohemorrhagic E. coli and other intestinal pathogens.

Molecular genetic etiology by whole exome sequence analysis in cases with familial type 1 diabetes mellitus without HLA haplotype predisposition or incomplete predisposition

OBJECTIVES

Familial transmission is observed in approximately 10% of cases with type 1 diabetes mellitus (T1DM). The most important gene determining susceptibility is the human leukocyte antigen complex (HLA) located on chromosome 6. More than 50 susceptible loci are associated with T1DM susceptibility have been identified in genes other than HLA. In this study, it was aimed to investigate the molecular genetic etiology by whole-exome sequence (WES) analysis in cases with familial T1DM with no or weakly detected HLA tissue type susceptibility. We aimed to identify new genes responsible for the development of type 1 diabetes and to reveal new genes that have not been shown in the literature before.

METHODS

Cases with at least one T1DM diagnosis in first-degree relatives were included in the study. In the first step, HLA DQ2 and DQ8 loci, which are known to be associated with T1DM susceptibility, were investigated by. In the second step, the presence of variants that could explain the situation was investigated by WES analysis in patients who were negative for both HLA DQ2 and HLA DQ8 haplotypes, HLA DQ2 negative, HLA DQ8 positive, and HLA DQ2 positive and HLA DQ8 negative patients.

RESULTS

The mean age and duration of diabetes of the 30 cases (Girl/Male: 17/13) were 14.9 ± 6 and 7.56 ± 3.84 years, respectively. There was consanguineous marriage in 5 (16%) of the families. As a result of filtering all exome sequence analysis data of two cases with DQ2 (DQB1*02) (-) and DQ8 (DQB1*03:02) (-), seven cases with DQ2 (DQB1*02) (+) and DQ8 (DQB1*03:02) (-), and one case with DQ2 (DQB1*02) (-) and DQ8 (DQB1*03:02) (+), seven different variants in seven different genes were detected in five cases. The pathogenicity of the detected variants were determined according to the "American College of Medical Genetics and Genomics (ACMG)" criteria. These seven variants detected were evaluated as high-score VUS (Variants of unknown/uncertain significance). In the segregation study conducted for the mutation in the POLG gene detected in case 5, this variant was detected in the mother of the case and his brother with T1DM. Segregation studies are ongoing for variants detected in other affected individuals in the family.

CONCLUSIONS

In conclusion, in this study, seven different variants in seven different genes were detected in five patients by WES analysis in familial T1DM patients with no or weak HLA tissue type susceptibility. These seven variants detected were evaluated as high-score VUS. POLG might be a novel candidate gene responsible for susceptibility to T1DM. Non-HLA genes directly responsible for the development of T1DM were not detected in any of the cases.

Membrane-bound IL-2 improves the expansion, survival, and phenotype of CAR Tregs and confers resistance to calcineurin inhibitors

Background

Regulatory T cells (Tregs) play an important role in the maintenance of immune homeostasis and the establishment of immune tolerance. Since Tregs do not secrete endogenous IL-2, they are especially dependent on external IL-2. IL-2 deficiency leads to lower Treg numbers, instability of the Treg phenotype and loss of immune regulation. After organ transplantation, patients are treated with calcineurin inhibitors (CNIs), which further limits available IL-2. Application of low-dose IL-2 expands Tregs but also activates NK and CD8+ T cells. It was recently shown that graft-specific Tregs recognizing mismatched MHC I molecules via a chimeric antigen receptor were far more potent than polyclonal Tregs in the regulation of immune responses after solid organ transplantation in a humanized mouse model.

Methods

Therefore, our aim was to enhance the function and stability of transferred CAR-Tregs via expression of membrane-associated IL-2 (mbIL-2).

Results

mbIL-2 promoted higher survival, phenotypic stability, and function among CAR-Tregs than observed in clinical trials. The cells were also more stable under inflammatory conditions. In a preclinical humanized mouse model, we demonstrated that mbIL-2 CAR Tregs survive better in the Treg niche than control CAR Tregs and are even resistant to CNI therapy without affecting other Tregs, thus acting mainly in cis.

Discussion

The functional and phenotypic improvements observed after membrane-attached IL-2 expression in CAR-Tregs will be important step for enhancing CAR-Treg therapies currently being tested in clinical trials for use after kidney and liver transplantation as well as in autoimmune diseases.