Search

TGF-β, essential for development and immunity, is expressed as a latent complex (L-TGF-β) non-covalently associated with its prodomain and presented on immune cell surfaces by covalent association with GARP. Binding to integrin αvβ8 activates L-TGF-β1/GARP. The dogma is that mature TGF-β must physically dissociate from L-TGF-β1 for signaling to occur. Our previous studies discovered that αvβ8-mediated TGF-β autocrine signaling can occur without TGF-β1 release from its latent form. Here, we show that mice engineered to express TGF-β1 that cannot release from L-TGF-β1 survive without early lethal tissue inflammation, unlike those with TGF-β1 deficiency. Combining cryogenic electron microscopy with cell-based assays, we reveal a dynamic allosteric mechanism of autocrine TGF-β1 signaling without release where αvβ8 binding redistributes the intrinsic flexibility of L-TGF-β1 to expose TGF-β1 to its receptors. Dynamic allostery explains the TGF-β3 latency/activation mechanism and why TGF-β3 functions distinctly from TGF-β1, suggesting that it broadly applies to other flexible cell surface receptor/ligand systems.

Regulatory T cells (Tregs) play a key role in suppressing systemic effector immune responses, thereby preventing autoimmune diseases but also potentially contributing to tumor progression. Thus, there is great interest in clinically manipulating Tregs, but the precise mechanisms governing in vitro-induced Treg (iTreg) differentiation are not yet fully understood. Here, we used multiparametric mass cytometry to phenotypically profile human iTregs during the early stages of in vitro differentiation at single-cell level. A panel of 25 metal-conjugated antibodies specific to markers associated with human Tregs was used to characterize these immunomodulatory cells. We found that iTregs highly express the transcription factor FOXP3, as well as characteristic Treg-associated surface markers (e.g. CD25, PD1, CD137, CCR4, CCR7, CXCR3, and CD103). Expression of co-inhibitory factors (e.g. TIM3, LAG3, and TIGIT) increased slightly at late stages of iTreg differentiation. Further, CD103 was upregulated on a subpopulation of iTregs with greater suppressive capacity than their CD103- counterparts. Using mass-spectrometry-based proteomics, we showed that sorted CD103+ iTregs express factors associated with immunosuppression. Overall, our study highlights that during early stages of differentiation, iTregs resemble memory-like Treg features with immunosuppressive activity, and provides opportunities for further investigation into the molecular mechanisms underlying Treg function.

We studied T-cell responses to SARS-CoV-2 in 19 pregnant subjects at different gestational weeks who received three doses of mRNA-based vaccination to prevent COVID-19. SARS-CoV-2 peptide pools were used for T-cell recognition studies: peptides were 15 amino acids long and had previously been defined in COVID-19-convalescent subjects. T-cell activation was evaluated with the AIM assay. Most subjects showed coordinated, spike-specific CD4+ and CD8+ T-cell responses and the development of T cell memory. Non-spike-specific T cells in subjects who were not aware of previous COVID-19 infection suggested a prior undetected, asymptomatic infection. CD4- CD8- double negative (DN) T cells were numerous, of which a percentage was specific for SARS-CoV-2 spike peptides. Regulatory T cells (Treg), both spike- and non-spike-specific, were also greatly expanded. Two Treg populations were defined: a population differentiated from naïve T cells, and pTreg, reverting from pro-inflammatory T cells. The Treg cells expressed CCR6, suggesting homing to the endometrium and vaginal epithelial cells. The pregnant women responded to SARS-CoV-2 vaccination. Asymptomatic COVID-19 was revealed by the T cell response to the non-spike peptides. The numerous DN T cells and Treg pointed our attention to new aspects of the adaptive immune response in vaccine recipients.

Autoimmune diseases, allergies, transplant rejections, generation of antidrug antibodies, and chronic inflammatory diseases have impacted a large group of people across the globe. Conventional treatments and therapies often use systemic or broad immunosuppression with serious efficacy and safety issues. Tolerogenic vaccines represent a concept that has been extended from their traditional immune-modulating function to induction of antigen-specific tolerance through the generation of regulatory T cells. Without impairing immune homeostasis, tolerogenic vaccines dampen inflammation and induce tolerogenic regulation. However, achieving the desired potency of tolerogenic vaccines as preventive and therapeutic modalities calls for precise manipulation of the immune microenvironment and control over the tolerogenic responses against the autoantigens, allergens, and/or alloantigens. Engineered nano-/microparticles possess desirable design features that can bolster targeted immune regulation and enhance the induction of antigen-specific tolerance. Thus, particle-based tolerogenic vaccines hold great promise in clinical translation for future treatment of aforementioned immune disorders. In this review, we highlight the main strategies to employ particles as exciting tolerogenic vaccines, with a focus on the particles' role in facilitating the induction of antigen-specific tolerance. We describe the particle design features that facilitate their usage and discuss the challenges and opportunities for designing next-generation particle-based tolerogenic vaccines with robust efficacy to promote antigen-specific tolerance for immunotherapy.

Fragile X mental retardation protein (FMRP), an RNA binding protein (RBP), is aberrantly hyper‐expressed in human tumors and plays an essential role in tumor invasion, metastasis and immune evasion. However, there is no small‐molecule inhibitor for FMRP so far. In this study, we developed the first FMRP‐targeting degrader based on PROteolysis TArgeting Chimera (PROTAC) technology and constructed a heterobifunctional PROTAC through linking a FMRP‐targeting G‐quadruplex RNA (sc1) to a von Hippel‐Lindau (VHL)‐targeting ligand peptide (named as sc1‐VHLL). Sc1‐VHLL specifically degraded endogenous FMRP via ubiquitination pathway in both mouse and human cancer cells. The FMRP degradation significantly changed the secretion pattern of cancer cells, resulting in higher expression of pro‐inflammatory cytokine and smaller amounts of immunomodulatory contents. Furthermore, sc1‐VHLL, when encapsulated into ionizable liposome nanoparticles (LNP), efficiently targeted tumor site and degraded FMRP in cancer cells. In CT26 tumor‐bearing mouse model, FMRP degradation within tumors substantially promoted the infiltration of lymphocytes and CD8 T cells and reduced the proportion of Treg cells, reshaping the proinflammatory tumor microenvironment and accordingly transforming cold tumor into hot tumor. When combined with immune checkpoint blockade (ICB) therapy, sc1‐VHLL based treatment remarkably inhibited the tumor growth. [ABSTRACT FROM AUTHOR]

Background: Regulatory T cells (Tregs) play a critical role in shaping the immunosuppressive microenvironment within tumors. Investigating the role of Tregs in Clear cell renal cell carcinoma (ccRCC) is crucial for identifying prognostic markers and therapeutic targets for ccRCC. Methods: Weighted gene co-expression network analysis (WGCNA) was utilized to pinpoint modules related to Treg infiltration in TCGA-KIRC samples. Following this, consensus clustering was employed to derive two clusters associated with Treg infiltration in ccRCC. A prognostic model was then developed using the gene module associated with Treg infiltration. We then evaluated the ability of the prognostic model to predict ccRCC overall survival and demonstrated that RCN1 can be used as a target to predict ccRCC prognosis. Results: We deduce that the two clusters associated with Treg infiltration exhibit distinct compositions of the immune microenvironment, pathway activations, prognosis, and drug sensitivities commonly utilized in ccRCC treatment. Furthermore, a 7-gene model risk score, developed based on ccRCC Treg infiltration, proved to be a reliable prognostic marker in both training and validation cohorts. Additionally, survival analysis indicated that RCN1 serves as a reliable prognostic factor for ccRCC. Single-cell sequencing analysis revealed that RCN1 is predominantly expressed in tumor cells. A pan-cancer analysis highlighted that RCN1 is linked with poor prognosis and the activation of inflammatory response pathways across various cancers. Conclusion: We developed a prognostic model associated with Treg infiltration, which facilitates the clinical categorization of ccRCC progression. Moreover, our findings underscore the significant potential of RCN1 as a ccRCC biomarker. [ABSTRACT FROM AUTHOR]

Background Methods Results Conclusion Recurrent miscarriage (RM) is influenced by immune factors, particularly regulatory T cells, which can impact immune function and miscarriage risk. Vitamin D (VD) is known to regulate the immune system, potentially improving pregnancy outcomes in RM patients. This study aims to assess the effect of VD adjuvant therapy on regulatory T cells and pregnancy outcomes in RM patients.Clinical data from 104 individuals with RM admitted to our hospital between March 2022 and February 2023 were allocated at random to either the VD group (VDG) or the control group (CG), with 52 patients in each group. Both groups received standard treatment; the CG was treated with aspirin, while the VDG received additional VD therapy. Outcomes measured included regulatory T cell proportion, metabolic factors, immune inflammatory markers, and pregnancy outcomes.After treatment, the proportion of regulatory T cells in VDG was considerably higher (p < 0.05). Additionally, triglyceride levels, leptin, fasting blood glucose, and fasting insulin were lower in the VDG, whereas adiponectin levels were higher (p < 0.05). Levels of progesterone, luteinizing hormone, and 25‐hydroxy VD were also higher in the VDG (p < 0.05). Furthermore, interleukin‐17, gamma interferon, tumor necrosis factor‐α, and C‐reactive protein were lower in the VDG (p < 0.05). The pregnancy success rate in the VDG was higher, and the preterm birth rate was lower (p < 0.05).Adjuvant treatment with VD can increase the proportion of regulatory T cells in peripheral blood of individuals with recurrent abortion, regulate metabolic disorder, alleviate immune inflammation, and improve pregnancy outcome. [ABSTRACT FROM AUTHOR]

The goal of food allergy (FA) prevention and treatment is to induce oral tolerance (OT). Appropriate nutritional interventions are essential to induce OT to food allergens. This review introduces the mechanism of OT and the importance of early nutritional interventions, and then firstly summarizes specific nutritional factors to induce the development of OT of FA, including proteins, vitamins, fatty acids, saccharides and probiotics. The regulatory mechanism mainly induces the development of tolerance by increasing local or systemic protective regulatory T cells (Tregs) to suppress FA, while the gut microbiota may also be changed to maintain intestinal homeostasis. For allergens-specific OT, the disruption to the structure of proteins and epitopes is critical for the induction of tolerance by hydrolyzed and heated proteins. Vitamins (vitamin A, D), fatty acids, saccharides and probiotics as allergens nonspecific OT also induce the development of OT through immunomodulatory effects. This review contributes to our understanding of OT in FA through nutritional interventions. Nutritional interventions play an important role in the induction of OT, and offer promising approaches to reduce allergy risk and alleviate FA. Moreover, due to the importance and diversity of nutrition, it must be the future trend of induction of OT in FA. [ABSTRACT FROM AUTHOR]

Background: Medication overuse headache (MOH) is the most common secondary headache disorder, resulting from chronic and excessive use of medication to treat headaches, for example, sumatriptan. In a recent study, we have shown that the peripheral C-C motif ligand 2 (CCL2), C-C motif chemokine receptor 2 (CCR2) and calcitonin-gene-related peptide (CGRP) signaling pathways interact with each other and play critical roles in the development of chronic migraine-related behavioral and cellular sensitization. In the present study, we investigated whether CCL2-CCR2 and CGRP signaling pathways play a role in the development of sumatriptan overuse-induced sensitization, and whether they are involved in its resolution by the low-dose interleukin-2 (LD-IL-2) treatment. Methods: Mice received daily sumatriptan administration for 12 days. MOH-related behavioral sensitization was assessed by measuring changes of periorbital mechanical thresholds for 3 weeks. CCL2-CCR2 and CGRP signaling pathways were inhibited by targeted gene deletion or with an anti-CCL2 antibody. Ca2+-imaging was used to examine whether repetitive sumatriptan treatment enhances CGRP and pituitary adenylate cyclase–activating polypeptide (PACAP) signaling in trigeminal ganglion (TG) neurons. LD-IL-2 treatment was initiated after the establishment of sumatriptan-induced sensitization. Immunohistochemistry and flow cytometry analyses were used to examine whether CCL2-CCR2 signaling controls regulatory T (Treg) cell proliferation and/or trafficking. Results: CCL2, CCR2 and CGRPα global KO mice exhibited robust sumatriptan-induced behavioral sensitization comparable to wild-type controls. Antibody neutralization of peripheral CCL2 did not affect sumatriptan-induced behaviors either. Repeated sumatriptan administration did not enhance the strength of CGRP or PACAP signaling in TG neurons. Nevertheless, LD-IL-2 treatment, which facilitated the resolution of sumatriptan-induced sensitization in wild-type and CGRPα KO mice, was completely ineffective in mice with compromised CCL2-CCR2 signaling. In CCL2 KO mice, we observed normal LD-IL-2-induced Treg expansion in peripheral blood, but the increase of Treg cells in dura and TG tissues was significantly reduced in LD-IL-2-treated CCL2 KO mice relative to wild-type controls. Conclusions: These results indicate that the endogenous CCL2-CCR2 and CGRP signaling pathways are not involved in sumatriptan-induced behavioral sensitization, suggesting that distinct molecular mechanisms underlie chronic migraine and MOH. On the other hand, peripheral CCL2-CCR2 signaling is required for LD-IL-2 to reverse chronic headache-related sensitization. [ABSTRACT FROM AUTHOR]

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes Coronavirus Disease 2019 (COVID-19), which can result in severe disease, often characterised by a 'cytokine storm' and the associated acute respiratory distress syndrome. However, many infections with SARS-CoV-2 are mild or asymptomatic throughout the course of infection. Although blood biomarkers of severe disease are well studied, less well understood are the inflammatory signatures in lung tissues associated with mild disease or silent infections, wherein infection and inflammation are rapidly resolved leading to sequelae-free recovery. Herein we described RNA-Seq and histological analyses of lungs over time in an omicron BA.1/K18-hACE2 mouse infection model, which displays these latter features. Although robust infection was evident at 2 days post infection (dpi), viral RNA was largely cleared by 10 dpi. Acute inflammatory signatures showed a slightly different pattern of cytokine signatures compared with severe infection models, and where much diminished 30 dpi and absent by 66 dpi. Cellular deconvolution identified significantly increased abundance scores for a number of anti-inflammatory pro-resolution cell types at 5/10 dpi. These included type II innate lymphoid cells, T regulatory cells, and interstitial macrophages. Genes whose expression trended downwards over 2–66 dpi included biomarkers of severe disease and were associated with 'cytokine storm' pathways. Genes whose expression trended upward during this period were associated with recovery of ciliated cells, AT2 to AT1 transition, reticular fibroblasts and innate lymphoid cells, indicating a return to homeostasis. Very few differentially expressed host genes were identified at 66 dpi, suggesting near complete recovery. The parallels between mild or subclinical infections in humans and those observed in this BA.1/K18-hACE2 mouse model are discussed with reference to the concept of "protective inflammation". [ABSTRACT FROM AUTHOR]

Pompe disease, a severe lysosomal storage disorder, is marked by heart problems, muscle weakness, and respiratory difficulties. This study aimed to identify novel markers for infantile-onset Pompe disease by analyzing key genes and immune cells infiltrating affected skeletal muscles, building on existing research linking its progression to the immune cell infiltration. The datasets GSE38680 and GSE159062 were downloaded and differential expression genes (DEGs) were identified. Potential markers were screened using support vector machine recursive feature elimination (SVM-RFE) analysis and least absolute shrinkage and selection operator (LASSO) regression models. To analyze DEGs and immune processes, 22 immune cell types in affected tissues were examined using CIBERSORT. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed significant enrichment in the calcium signaling pathway, phosphatidylinositol signaling system, ubiquitin-mediated proteolysis and JAK-STAT signaling pathway. Machine learning identified GPNMB, CALML6 and TRIM7 as key genes. Immune cell infiltration analysis showed that the expression levels of the above three genes were closely related to immune cells in our target population under study, including T cells regulatory (Tregs), monocytes, macrophages M0, resting and activated dendritic cells, naive and memory B cells. Overall, our study results may provide new clues for exploring markers related to Pompe disease by highlighting key genes and their relationship with immune infiltration, offering insights into the disease's development. However, previous studies have shown limited evidence of significant immune cell infiltration in muscle biopsies from Pompe patients, and this lack of direct evidence necessitates further investigation and experimental validation in laboratory settings to confirm these associations. [ABSTRACT FROM AUTHOR]

Background Aim Methods Results Conclusion Severe cutaneous adverse reactions (SCARs) mediated by cytotoxic T lymphocytes are a series of life‐threatening conditions with a mortality of 4%–20%. The clinical application of tumor necrosis factor‐alpha (TNF‐α) antagonist improves the outcome of some SCARs patients; however, this is complicated by the elusive and varied immunopathogenesis.To investigate whether IgE antibody responses to HEMAs are associated with AD, its severity, and response to dupilumab.To clarify the precise process and optimize the therapy regimen of SCARs, we performed single‐cell sequencing, in vitro functional and clinical analysis of patients with SCARs.We observed that TNF‐α breaks drug‐specific T‐cell tolerance by inhibiting the expression of V‐type immunoglobulin domain‐containing suppressor of T‐cell activation (VISTA). Furthermore, TNF‐α generated a positive feedback loop in the early phase of drug‐specific T‐cell activation, whereby B cells acted reciprocally on the corresponding T cells to reinforce TNF‐α cytokine expression. In contrast, this pathway of TNF‐α‐VISTA signaling did not operate in memory effector T cells. Drug‐specific memory effector T‐cell responses were inhibited by increasing Treg cell expression in a negative feedback loop, with TNF‐α antagonists preventing the inhibitory effect. These observations align with the clinical analysis that early but not late intervention with TNF‐α antagonists significantly improved outcomes in SCARs patients.Our findings defining feedback regulation of VISTA and Treg cells by TNF‐α in different stages of the drug‐specific T‐cell response and, indicate that a Treg agonists, instead of TNF‐α antagonists, could be used for treatment of patients with progressive SCARs. [ABSTRACT FROM AUTHOR]

Lymphocyte activation gene 3 (Lag3) is an inhibitory co-receptor expressed on activated T cells and has been proposed to regulate regulatory T (Treg) cell function. However, its precise modality and mechanisms remain elusive. We generated Treg cell-specific Lag3-mutant mouse models and found that Lag3 was essential for Treg cell control of autoimmunity. RNA sequencing analysis revealed that Lag3 mutation altered genes associated with metabolic processes, especially Myc target genes. Myc expression in Lag3-mutant Treg cells was increased to the level seen in conventional T helper (Th)1-type effector cells and directly correlated with their metabolic profiles and in vivo suppressive functions. The phosphatidylinositol 3-kinase (PI3K)-Akt-Rictor pathway was activated in Lag3-mutant Treg cells, and inhibiting PI3K, Rictor, or lactate dehydrogenase A (Ldha), a key Myc target enzyme converting pyruvate to lactate, was sufficient to restore normal metabolism and suppressive function in Lag3-mutant Treg cells. These findings indicate that Lag3 supports Treg cell suppression partly by tuning Myc-dependent metabolic programming. [Display omitted] • Lag3 expression on Treg cells is required for adequate control of inflammation • Lag3-derived intracellular signals play a key role in Treg cell function • Lag3 regulates Myc expression and the metabolism of Treg cells • Lag3 controls Treg cell metabolism via the PI3K-Akt-Rictor pathway Lag3 is a co-inhibitory receptor expressed on T cells, including Foxp3+ regulatory T cells. However, the mechanism underlying Lag3 functions in Treg cells remains largely unclear. Kim et al. generated Treg-specific Lag3 mutant mice and reported that Lag3 supports Treg cell function by inhibiting Myc expression and altering metabolic profiles through the PI3K-Akt-Rictor pathway. [ABSTRACT FROM AUTHOR]

Background: Regulatory T (Treg) cells is required to dampen immune responses against intestinal microbiota, which aid in a healthy body to promise that the resident gut microbiota should not attract the attention of the immune system. Inflammation and inflammatory bowel disease (IBD) can be induced if the immune system fails to ignore the resident gut microbiota and targets them instead. D-mannose, a common monosaccharide in nature, has been shown to ameliorate multiple autoimmune diseases. This study aimed to investigate the therapeutic effect of D-mannose on mice ulcerative colitis (UC) induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS), and elucidate its underlying mechanisms. Methods: To simulate human IBD, we constructed a mouse model of UC by injecting TNBS into the colon. Results: Our results demonstrated that D-mannose treatment effectively alleviated TNBS-induced UC in mice, as evidenced by the amelioration of UC symptoms. D-mannose treatment significantly reduced inflammation by decreasing the expression of proinflammatory cytokines and inflammation mediators. D-mannose treatment also significantly inhibited oxidative stress, promoted the expression of GSH and SOD, decreased the expression of MDA. Mechanistically, D-mannose upregulated the proportion of both CD4(+) Tregs and CD8(+) Tregs. Conclusion: In summary, our study provides the first evidence of the therapeutic effect of D-mannose on mice with UC, which is likely mediated by upregulating Treg proportions. [ABSTRACT FROM AUTHOR]

Background: Following ischemic stroke, non-neuronal cells within the nervous system play a crucial role in maintaining neurovascular unit functions, regulating metabolic and inflammatory processes of the nervous system. Investigating the functions and regulation of these cells, particularly immune cells, deepens our understanding of the complex mechanisms of neuroinflammation and immune modulation after ischemic stroke and provides new perspectives and methods for immune-related therapy. Methods: The annual distribution, journals, authors, countries, institutions, and keywords of articles published between 2015 and 2024 were visualized and analyzed using CiteSpace and other bibliometric tools. Results: A total of 1,089 relevant articles or reviews were included, demonstrating an overall upward trend; The terms "cerebral ischemia," "immune response," "brain ischemia," "cerebral inflammation," "neurovascular unit," and "immune infiltration," etc. are hot keywords in this field. Conclusion: In recent years, research on immune-related therapy for ischemic stroke has focused on mechanisms of occurrence, protection and repair of the blood-brain barrier (BBB) by non-neuronal cells, and regulation of immunosuppression and inflammation. Among these, reducing BBB disruption to minimize secondary brain damage has become a hotspot. At the same time, the complex roles of immune responses have attracted attention, particularly the balance between regulatory T cells and Th17 cells in regulating neuroinflammation and promoting neurological function recovery, which is crucial to reduce secondary neuronal damage and improve prognosis, potentially establishing a pivotal frontier in this domain of investigation. [ABSTRACT FROM AUTHOR]

Background: Transforming growth factor (TGF)-ß1 is a pleiotropic cytokine that can promote tumor growth and suppress antitumor immune responses. Latent TGF-ß1 associates with glycoprotein-A repetition predominant (GARP) on the surface of regulatory T cells prior to its activation and release. Livmoniplimab is a monoclonal antibody (mAb) that binds the GARP:TGF-ß1 complex to inhibit activation and release of TGF-ß1. It is in clinical development in combination with budigalimab, an anti-programmed cell death protein 1 Fc-modified mAb. The first-in-human, phase 1, dose-escalation results are presented herein (ClinicalTrials.gov : NCT03821935). Methods: The dose-escalation phase enrolled adult patients with advanced solid tumors. Patients received escalating doses of livmoniplimab ranging from 3mg to 1500mg, once every 2 weeks (Q2W), as monotherapy or in combination with a 500mg fixed dose of budigalimab Q4W. The primary objective of the dose escalation was to determine the recommended phase 2 dose. Secondary objectives were to assess safety and pharmacokinetics (PK), and exploratory objectives included evaluating preliminary efficacy. Results: Fifty-seven patients enrolled in the dose escalation: 23 in monotherapy cohorts and 34 in combination therapy cohorts. Dose-limiting toxicities were limited, no maximum tolerated dose was reached, and the maximum administered dose of 1500mg was selected for dose expansion. The most common adverse events reported in monotherapy-treated patients were fatigue, anemia, and nausea, and those in combination therapy-treated patients were pruritus, fatigue, nausea, and anemia. Livmoniplimab exhibited dose-proportional PK, and peripheral blood biomarker data demonstrated saturation of the GARP:TGF-ß1 complex on platelets at livmoniplimab doses within the linear PK range. No objective tumor responses were observed in the monotherapy dose escalation. However, the objective response rate was 15% in the combination dose escalation, with a median response duration of 8.4 months. Conclusion: Livmoniplimab was well-tolerated as monotherapy and in combination with budigalimab in the dose-escalation phase. Encouraging preliminary efficacy was demonstrated in the combination dose escalation in heavily pretreated patients, supporting further development of this novel drug combination in patients with advanced solid tumors. [ABSTRACT FROM AUTHOR]

Papillary thyroid carcinoma (PTC) is the most common subtype of thyroid carcinoma. The most effective treatment for PTC is surgical resection, and patients who undergo surgery have good survival outcomes, but some patients have distant metastasis or even multiorgan metastases at the time of initial diagnosis. Distant metastasis is associated with poorer prognosis and a higher mortality rate. Helper T lymphocyte 17 (Th17) cells and regulatory T lymphocytes (Tregs) play different roles in PTC, and the Th17/Treg balance is closely related to the progression of PTC. Th17 cells play anticancer roles, whereas Tregs play cancer-promoting roles. A Th17/Treg imbalance promotes tumor progression and accelerates invasive behaviors such as tumor metastasis. Th17/Treg homeostasis can be regulated by the TGF‐β/IL‐2 and IL‐6 cytokine axes. Immune checkpoint inhibitors contribute to Treg/Th17 cell homeostasis. For PTC, monoclonal antibodies against CTLA-4, PD-1 and PD-L1 inhibit the activation of Tregs, reversing the Th17/Treg cell imbalance and providing a new option for the prevention and treatment of PTC. This article reviews the role of Tregs and Th17 cells in PTC and their potential targets, aiming to provide better treatment options for PTC. [ABSTRACT FROM AUTHOR]

At present, the characteristics of double-hit multiple myeloma (DHMM) are unknown. We retrospectively analyzed the clinical data from 433 new diagnosed MM patients and found that DHMM have a higher β2-MG level and percentage of bone marrow plasma cell. Cox regression analysis showed that the prognosis of DHMM was not limited by clinical indicators. The abnormal proliferation of bone marrow in DHMM is obvious, and the proportion of poorly differentiated plasma cell is high. By collecting specimens from our center and performing flow cytometry to analyze the immunophenotypic and functional characteristics of lymphocyte subpopulations, we found that DHMM had a higher ratio of Tregs cells, and the proportion of iTregs cells was also significantly higher than non-DHMM (P < 0.05). Moreover, DHMM had higher levels of TGF-β1 and IL-10, and TGF-β1 and IL-10 were positively correlated with iTregs (P < 0.05). In addition, DHMM was highly expressed PD-1 on CD8 + T cells and had a higher proportion of CD38highTregs cells. In vitro we have shown that the addition of TGF-β1 antibody or CD38 antibody can effectively inhibit the proportion of CD38high Tregs. This study describes the characteristics of DHMM based on bicentric data, which is helpful to better provide theoretical support for the treatment of DHMM. [ABSTRACT FROM AUTHOR]

Regulatory T cells (Tregs), an essential component of the human immune system, are a heterogeneous group of T lymphocytes with the ability to suppress immune responses and maintain immune homeostasis. Recent evidence indicates that Tregs may impair antitumor immunity and facilitate cancer progression by weakening functions of effector T cells (Teffs). Consequently, targeting Tregs to eliminate them from tumor microenvironments to improve Teffs' activity could emerge as an effective strategy for cancer immunotherapy. This review outlines the biology of Tregs, detailing their origins, classification, and crucial markers. Our focus lies on the complex role of Tregs in cancer's development, progression and treatment, particularly on their suppressive role upon antitumor responses via multiple mechanisms. We delve into Tregs' involvement in immune checkpoint blockade (ICB) therapy, their dual effect on cancer immunotherapy and their potential biomarkers for ICB therapy effectiveness. We also summarize advances in the therapies that adjust Tregs to optimize ICB therapy, which may be crucial for devising innovative cancer treatment strategies. [ABSTRACT FROM AUTHOR]

The crosstalk between cuproptosis and the tumor immune microenvironment (TIME) is vital during clear cell renal cell carcinoma (ccRCC) malignant progression. However, the underlying molecular mechanisms regulate this cross-talk remain elusive. Through tailored machine learning, we analyze clinical ccRCC data from The Cancer Genome Atlas (TCGA) to explore the critical factors that regulate the interaction among cuproptosis, TIME, and tumor progression. We found that rhomboid-like 2 (RHBDL2), critical gene affecting this process, might inhibit cuproptosis-related genes (CRGs) and promotes ccRCC progression through the Wnt/β-catenin pathway. Next, knocking down RHBDL2 expression increased the cuproptosis-related genes ferredoxin 1 (FDX1) and lipoic acid synthase (LIAS) levels but reduced forkhead box P3 (FOXP3) levels and tumor growth in vivo and in vitro models. By employing HLY78, Wnt/β-catenin pathway activator, we rescued the expression of CRGs and the malignant proliferation and metastasis capacity in ccRCC cells with RHBDL2 knockdown. Mechanistically, RHBDL2 inhibits cuproptosis and promotes malignant progression of ccRCC through the Wnt/β-catenin pathway. Abnormal RHBDL2 expression may cause the suppressive TIME formation by regulating Treg-cell infiltration, thus triggering immune escape. In summary, our results indicated that RHBDL2 is an oncogene that induces tumorigenesis and targeting RHBDL2 may be novel therapeutic direction for metastatic ccRCC. [ABSTRACT FROM AUTHOR]

Background: Ki67 index changes during the treatment of metastatic pancreatic neuroendocrine tumor (PanNET) treatment. The study aimed to detect alterations of grade based on Ki67 index and immune microenvironment in PanNET responding to capecitabine/temozolomide (CapTem). Method: Retrospective data of patients with PanNET were collected. In control group, 35 patients underwent surgery immediately after biopsy. In CapTem group, 38 patients received CapTem after biopsy and responded well to treatment (defined as either stable disease or partial response), and subsequently underwent surgery. All patients have pathological Ki67 index at biopsy and after surgery. CD163 + CD68 + CD206 + M2 macrophages, CD68 + CD86 + CD80 + M1 macrophages, CD11b + CD33 + myeloid-derived suppressor cells, and CD4 + CD25 + regulatory T cells were stained using multiplex immunofluorescence. Results: In control group, the paired grade based on Ki67 index directly after surgery showed no upgrade or downgrade compared to biopsy. In patients who responded well to CapTem, the grade based on Ki67 index before and after CapTem was altered. Thirteen patients had upgraded Ki67 index and 11 patients had downgraded. The proportion of stable disease was higher in the upgraded group compared to downgraded group (p = 0.0155). And upgraded group had a significantly shorter mPFS than patients in the downgrade group (8.5 months vs. 20 months, HR 4.834, 95% CI 1.414 to 16.53, p = 0.012). M1 macrophages was significantly lower in the downgraded group than in the Ki67 upgraded group (p < 0.001). Conclusion: Grade based on Ki67 index and immune environment change in PanNET patients responding well to CapTem. Patients with downgraded had longer mPFS compared to those with upgraded. It is necessary to reassess the Ki67 index after CapTem treatment, even in patients responding well to CapTem. [ABSTRACT FROM AUTHOR]

Artemisinin and its derivatives are widely recognized as first-line treatments for malaria worldwide. Recent studies have demonstrated that artemisinin-based antimalarial drugs, such as artesunate, dihydroartemisinin, and artemether, not only possess excellent antimalarial properties but also exhibit antitumor, antifungal, and immunomodulatory effects. Researchers globally have synthesized artemisinin derivatives like SM735, SM905, and SM934, which offer advantages such as low toxicity, high bioavailability, and potential immunosuppressive properties. These compounds induce immunosuppression by inhibiting the activation of pathogenic T cells, suppressing B cell activation and antibody production, and enhancing the differentiation of regulatory T cells. This review summarized the mechanisms by which artemisinin and its analogs modulate excessive inflammation and immune responses in rheumatic and skeletal diseases, autoimmune inflammatory diseases, and autoimmune disorders, through pathways including TNF, Toll-like receptors, IL-6, RANKL, MAPK, PI3K/AKT/mTOR, JAK/STAT, and NRF2/GPX4. Notably, in the context of the NF-κB pathway, artemisinin not only inhibits NF-κB expression by disrupting upstream cascades and/or directly binding to NF-κB but also downregulates multiple downstream genes controlled by NF-κB, including inflammatory chemokines and their receptors. These downstream targets regulate various immune cell functions, apoptosis, proliferation, signal transduction, and antioxidant responses, ultimately intervening in systemic autoimmune diseases and autoimmune responses in organs such as the kidneys, nervous system, skin, liver, and biliary system by modulating immune dysregulation and inflammatory responses. Ongoing multicenter randomized clinical trials are investigating the effects of these compounds on rheumatic, inflammatory, and autoimmune diseases, with the aim of translating promising preclinical data into clinical applications. [ABSTRACT FROM AUTHOR]

Background: Tregs plays a critical role in the development of secondary injuries in diseases. Accumulating evidence suggests an association between ischemic stroke and renal dysfunction; however, the underlying mechanisms remain unclear. This study aimed to investigate the potential of Tregs in inhibiting the activation of astrocytes after focal cerebral infarction. Methods: This study aimed to investigate the renal consequences of focal cerebral ischemia by subjecting a mouse model to transient middle cerebral artery occlusion (tMCAO). Subsequently, we assessed renal fibrosis, renal ferroptosis, Treg infiltration, astrocyte activation, as well as the expression levels of active GPX4, FSP1, IL-10, IL-6, and IL-2 after a 2-week period. Results: In the tMCAO mouse model, depletion of tregs protected against activation of astrocyte and significantly decreased FSP1, IL-6, IL-2, and NLRP3 expression levels, while partially reversing the changes in Tregs. Mechanistically, tregs depletion attenuates renal fibrosis by modulating IL-10/GPX4 following cerebral infarction. Conclusion: Tregs depletion attenuates renal fibrosis by modulating IL-10/GPX4 following cerebral infarction. [ABSTRACT FROM AUTHOR]

Postmenopausal bone loss due to estrogen deficiency necessitates effective therapeutic strategies. Our study explores targeting macrophage Aurora A kinase to mitigate bone loss. Aurora A kinase phosphorylation is observed being increased in bone marrow‐derived macrophages (BMDMs) from ovariectomy (OVX) mice, along with a reduction in programmed death‐ligand 1 (PD‐L1) expression. Detailed analysis reveals that PD‐L1 plays an immunomodulatory role by lowering the ratio of T helper 17 cells and regulatory T cells. The metabolic shift toward glycolysis through transcriptome sequencing, induced by Aurora A kinase inhibition, is essential for PD‐L1 expression in BMDMs. The interaction between Aurora A kinase and cytochrome C oxidase subunit 5B is found to enhance PD‐L1 expression. To apply these findings therapeutically, a multifunctional system is developed using a Nickel‐metal organic framework combined with bisphosphonate and MLN8237 (BP@Ni‐MOF/MLN8237). This system targets bone tissues through bisphosphonate and effectively delivers MLN8237 to macrophages, promoting PD‐L1 expression for a favorable immune environment. Moreover, this system exhibits an obvious angiogenic effect. The present study highlights the crucial roles of macrophage Aurora A kinase and PD‐L1 in maintaining bone homeostasis as well as the angiogenesis effect by Ni‐MOF engineered system, presenting a promising therapeutic approach to prevent postmenopausal bone loss. [ABSTRACT FROM AUTHOR]

The heterologous immunity of live pathogens leads to the emergence of this approach as a pivotal component in cancer immunotherapy. However, virulence, inflammatory‐related toxicity, and the induction of Treg cells after treatment hinder their clinical translation. Here, to exploit the heterologous immunity of live pathogens without risks, a virulence‐free reconstituted synthetic nanopathogen (RSnP) is developed by the cell wall skeleton of disrupted Mycobacterium bovis and the incorporation of timely‐activating Toll‐like receptor 7/8 agonists of which multifaceted activities can be promoted by endolysosomal enzymes. Immunization with RSnP, even without tumor‐specific antigens, exhibits potent antitumor efficacy against melanoma, breast cancer, and bladder cancer by promoting antitumor effector cells (CD8+ T cells, NK cells, M1 macrophages, and Th17 cells) and proinflammatory cytokines (IL‐12p70, TNF‐α, and IL‐6) while simultaneously mitigating immunosuppressive myeloid cells (MDSCs and M2 macrophages) in the tumor microenvironment, surpassing the therapeutic efficacies of approved live‐BCG drug and mRNA vaccine. The increase in CCR8+Foxp3+ Treg cells induced to counteract RSnP treatment can be attenuated by anti‐CCR8 antibody, a depletion antibody for tumor‐specific Treg cells, to synergize therapeutic efficacy with relieved autoimmunity. RSnP can be a therapeutic nanomedicine platform across heterologous cancers and emerging infectious virus variants with minimized toxicity. [ABSTRACT FROM AUTHOR]

Background: Immune checkpoint inhibitors (ICI) have dramatically improved the life expectancy of patients with metastatic melanoma. However, about half of the patient population still present resistance to these treatments. We have previously shown Notch1 contributes to a non-inflamed TME in melanoma that reduces the response to ICI. Here, we addressed the therapeutic effects of a novel anti-Notch1 neutralizing antibody we produced, alone and in combination with immune checkpoint inhibition in melanoma models. Methods: Anti-Notch1 was designed to interfere with ligand binding. Mice were immunized with a peptide encompassing EGF-like repeats 11–15 of human Notch1, the minimal required region that allows ligand binding and Notch1 activation. Positive clones were expanded and tested for neutralizing capabilities. Anti-Notch1-NIC was used to determine whether anti-Notch1 was able to reduce Notch1 cleavage; while anti-SNAP23 and BCAT2 were used as downstream Notch1 and Notch2 targets, respectively. K457 human melanoma cells and the YUMM2.1 and 1.7 syngeneic mouse melanoma cells were used. Cell death after anti-Notch1 treatment was determined by trypan blue staining and compared to the effects of the gamma-secretase inhibitor DBZ. 10 mg/kg anti-Notch1 was used for in vivo tumor growth of YUMM2.1 and 1.7 cells. Tumors were measured and processed for flow cytometry using antibodies against major immune cell populations. Results: Anti-Notch1 selectively inhibited Notch1 but not Notch2; caused significant melanoma cell death in vitro but did not affect normal melanocytes. In vivo, it delayed tumor growth without evident signs of gastro-intestinal toxicities; and importantly promoted an inflamed TME by increasing the cytotoxic CD8+ T cells while reducing the tolerogenic Tregs and MDSCs, resulting in enhanced efficacy of anti-PD-1. Conclusions: Anti-Notch1 safely exerts anti-melanoma effects and improves immune checkpoint inhibitor efficacy. Thus, anti-Notch1 could represent a novel addition to the immunotherapy repertoire for melanoma. [ABSTRACT FROM AUTHOR]

Introduction: Open reduction and fixation are the standard of care for treating mandibular fractures and usually lead to successful healing. However, complications such as delayed healing, non-union, and infection can compromise patient outcomes and increase healthcare costs. The initial inflammatory response, particularly the response involving specific CD8+ T cell subpopulations, is thought to play a critical role in healing long bone fractures. In this study, we investigated the role of these immune cell profiles in patients with impaired healing of mandibular fractures. Materials and methods: In this prospective study, we included patients with mandibular fractures surgically treated at Charité – Universitätsmedizin Berlin, Germany, between September 2020 and December 2022. We used follow-up imaging and clinical assessment to evaluate bone healing. In addition, we analyzed immune cell profiles using flow cytometry and quantified cytokine levels using electrochemiluminescence-based multiplex immunoassays in preoperative blood samples. Results: Out of the 55 patients enrolled, 38 met the inclusion criteria (30 men and 8 women; mean age 32.18 years). Radiographic evaluation revealed 31 cases of normal healing and 7 cases of incomplete consolidation, including 1 case of non-union. Patients with impaired healing exhibited increased levels of terminally differentiated effector memory CD8+ T cells (TEMRA) and a higher TEMRA to regulatory T cell (Treg) ratio, compared with those with normal healing. Conclusions: Our analysis of mandibular fracture cases confirms our initial hypothesis derived from long bone fracture healing: monitoring the TEMRA to Treg ratio in preoperative blood can be an early indicator of patients at risk of impaired bone healing. Radiologic follow-up enabled us to detect healing complications that might not be detected by clinical assessment only. This study highlights the potential of individual immune profiles to predict successful healing and may form the basis for future strategies to manage healing complications. [ABSTRACT FROM AUTHOR]

Background: Ischemic stroke (IS) is a global health issue linked to lipid metabolism and immune cell responses. This study uses Mendelian randomization (MR) to identify genetic risk factors for IS subtypes using comprehensive genetic data from lipidomic and immune cell profiles. Methods: We assessed genetic susceptibility to IS across 179 lipids and 731 immune cell phenotypes using instrumental variables (IVs) from recent genome-wide association studies. A two-sample MR approach evaluated correlations, and a two-step MR mediation analysis explored the role of immune cell phenotypes in the lipid-IS pathway. Sensitivity analyses, including MR-Egger and Cochran Q tests, ensured robust results. Results: Genetic IVs for 162 lipids and 614 immune cell phenotypes were identified. Significant genetic causality was found between 35 lipids and large artery stroke (LAS), with 12 as risk factors (sterol esters, phosphatidylcholines, phosphatidylethanolamines) and 23 as protective factors (phosphatidylcholines, phosphatidylethanolamines, phosphatidylinositols). For small vessel stroke (SVS), 8 as risk factors (sterol esters, phosphatidylcholines), and 2 as protective factors (phosphatidylinositol, sphingomyelin). For cardioembolic stroke (CS), 2 as risk factors, and 4 as protective factors. Mediation analysis revealed that CCR2 on granulocytes, CD11c on CD62L+ myeloid dendritic cells, and FSC-A on granulocytes mediated the lipid-immune cell-LAS pathway, while CD4 on activated CD4 regulatory T cells and CD4 on activated & secreting CD4 regulatory T cells mediated the lipid-immune cell-SVS pathway. Conclusion: This study identifies genetic links between specific lipids and IS subtypes, highlights immune cells' role in IS risk and mediation, suggests new therapeutic targets, and uncovers IS genetic drivers. [ABSTRACT FROM AUTHOR]

Background: A dietary supplementation with conjugated linoleic acid (CLA) was shown to attenuate inflammation and increase the proportions of circulating regulatory T cells (Tregs) and M2-type macrophages in disease models such as autoimmune encephalitis and arteriosclerosis. Since Tregs and anti-inflammatory (M2-type) macrophages were found to enhance stroke recovery, we hypothesized that CLA-supplementation might improve stroke recovery via immune modulatory effects. Methods: Functional assessment was performed over 90 days after induction of experimental photothrombotic stroke in wild type mice (n = 37, sham n = 10). Subsequently, immunological characterization of different immunological compartments (n = 16), ex vivo magnetic resonance (MR, n = 12) imaging and immunohistochemical staining (n = 8) was performed. Additionally, we tested the effect of CLA in vitro on peripheral blood mononuclear cells from human stroke patients and healthy controls (n = 12). Results: MR diffusion tensor imaging (DTI) demonstrated enhanced microstructural reorganization of interhemispheric white matter tracts, dependent on lesion size. Functional recovery over 90 days remained unaffected. Detailed immunological analyses across various compartments revealed no significant long-term immunological alterations due to CLA. However, analyses of human blood samples post-stroke showed reduced levels of pro-inflammatory interferon-γ (IFN-γ) and tumor necrosis factor alpha (TNF-α) release by T-lymphocytes following in vitro treatment with CLA. Conclusion: We aimed to explore the efficacy of a dietary intervention with minimal known side effects that could be accessible to human stroke patients, regardless of the degree of disability, and without the risks associated with aggressive immunomodulatory therapies. Our main findings include improved microstructural reorganization in small infarcts and a reduced inflammatory response of human T cells in vitro. [ABSTRACT FROM AUTHOR]

The synthesized compound, 1-(2-ethoxyethyl)-4-(pent-1-yn-1-yl)piperidin-4-yl propionate (EPPP), and its 1:1 complex with β-cyclodextrin (EPPPβCD) have been characterized for the first time through a comprehensive suite of analytical methods. This study explores the therapeutic potential of EPPPβCD in modulating immune responses and accelerating the resolution of septic inflammation induced by chromium and vanadium ions in outbred male rats. The research highlights the significant impact of EPPPβCD on the dynamics of regulatory T lymphocytes (Tregs), notably causing a reduction in the CD4+CD25+ fractions at the onset of inflammation. This effect is attributed to the inhibition of Treg proliferation, which is crucial in hastening the resolution of inflammation. These findings underscore the potential of EPPPβCD as a promising therapeutic agent in controlling and mitigating inflammation mediated by heavy metal exposure, thereby offering a new avenue for the development of anti-inflammatory treatments. [ABSTRACT FROM AUTHOR]

COVID-19, caused by SARS-CoV-2, triggers a complex immune response, with T regulatory cells (Tregs) playing a crucial role in maintaining immune homeostasis and preventing excessive inflammation. The current study investigates the function of T regulatory cells during COVID-19 infection and the subsequent recovery period, emphasizing their impact on immune regulation and inflammation control. We conducted a comprehensive analysis of Treg subpopulations in peripheral blood samples from COVID-19 patients at different stages: acute infection, early convalescence, and long-term recovery. Flow cytometry was employed to quantify Tregs including "naïve", central memory (CM), effector memory (EM), and terminally differentiated CD45RA+ effector cells (TEMRA). Additionally, the functional state of the Tregs was assessed by the expression of purinergic signaling molecules (CD39, CD73). Cytokine profiles were assessed through multiplex analysis. Our findings indicate a significant decrease in the number of Tregs during the acute phase of COVID-19, which correlates with heightened inflammatory markers and increased disease severity. Specifically, we found a decrease in the relative numbers of "naïve" and an increase in EM Tregs, as well as a decrease in the absolute numbers of "naïve" and CM Tregs. During the early convalescent period, the absolute counts of all Treg populations tended to increase, accompanied by a reduction in pro-inflammatory cytokines. Despite this, one year after recovery, the decreased subpopulations of regulatory T cells had not yet reached the levels observed in healthy donors. Finally, we observed the re-establishment of CD39 expression in all Treg subsets; however, there was no change in CD73 expression among Tregs. Understanding these immunological changes across different T regulatory subsets and adenosine signaling pathways offers important insights into the disease's pathogenesis and provides a broader view of immune system dynamics during recovery. [ABSTRACT FROM AUTHOR]

Comprehensive characterization of AML-associated T cells during disease progression is essential to identify relevant immune escape mechanisms and new immunotherapeutic approaches. Investigating the processes that lead to an immunosuppressive environment under progression of AML is difficult in humans, because by the time of diagnosis the disease is often progressed far beyond the initial stages. Therefore, to investigate T-cell phenotypes during progression a C57BL/6 mouse model was used. The CD3+ T cells were characterized by performing multiparametric flow analyses at different time points (day 0 = healthy mice, day 7, day 14, and day 21). The study revealed that the spleen is highly infiltrated by reg CD4+ T cells at day 21 of AML progression. These spleen-infiltrating reg CD4+ T cells mainly showed an effector memory differentiation with high expression and co-expression of the checkpoint molecules TIGIT, PD-1, OX40, and the two ectoenzymes CD39 and CD73. Substantial expression of the checkpoint molecules was restricted to the central memory and effector memory compartments. Furthermore, functional evaluation of TIGIT was performed. Blocking TIGIT resulted in a significantly increased lysis of C1498 AML cells in cocultures with AML-primed CD3+ T cells. Together these data confirm that the expression of the checkpoint receptor TIGIT is relevant for dysfunction of AML-associated T cells and, thus, represents a suitable target for future immunotherapeutic approaches. [ABSTRACT FROM AUTHOR]

Type 1 diabetes (T1D) is an autoimmune disease that is caused by autoreactive T cell-mediated destruction of insulin-producing β cells in the pancreatic islets. Although naive autoreactive T cells are initially primed by islet antigens in pancreas-draining lymph nodes (pan-LNs), the adhesion molecules that recruit T cells into pan-LNs are unknown. We show that high endothelial venules in pan-LNs of young nonobese diabetic mice have a unique adhesion molecule profile that includes strong expression of mucosal addressin cell adhesion molecule-1 (MAdCAM-1). Anti-MAdCAM-1 antibody blocked more than 80% of the migration of naive autoreactive CD4+ T cells from blood vessels into pan-LNs. Transient blockade of MAdCAM-1 in young nonobese diabetic mice led to increased numbers of autoreactive regulatory CD4+ T cells in pan-LNs and pancreas and to long-lasting protection from T1D. These results indicate the importance of MAdCAM-1 in the development of T1D and suggest MAdCAM-1 as a potential therapeutic target for treating T1D. [ABSTRACT FROM AUTHOR]

Simple Summary: STING agonists face challenges in breast cancer treatment due to their lower accumulation in tumors and rapid clearance from the body, resulting in a short duration of therapeutic effect. Novel phase-transitional liposomes loaded with STING agonists have been developed to overcome these limitations and are specifically designed for low-intensity focused ultrasound (LIFU)-assisted molecular imaging and precise treatment of breast cancer. With the assistance of LIFU, iRGD-modified liposomes (a targeting peptide) undergo a phase transition into microbubbles, leading to enhanced ultrasound molecular imaging of tumors and facilitating breast cancer immunotherapy by releasing STING agonists from the ultrasound-targeted liposomes. Background: Pharmacologically targeting the STING pathway offers a novel approach to cancer immunotherapy. However, small-molecule STING agonists face challenges such as poor tumor accumulation, rapid clearance, and short-lived effects within the tumor microenvironment, thus limiting their therapeutic potential. To address the challenges of poor specificity and inadequate targeting of STING in breast cancer treatment, herein, we report the design and development of a targeted liposomal delivery system modified with the tumor-targeting peptide iRGD (iRGD-STING-PFP@liposomes). With LIFU irradiation, the liposomal system exploits acoustic cavitation, where gas nuclei form and collapse within the hydrophobic region of the liposome lipid bilayer (transient pore formation), which leads to significantly enhanced drug release. Methods: Transmission electron microscopy (TEM) was used to investigate the physicochemical properties of the targeted liposomes. Encapsulation efficiency and in vitro release were assessed using the dialysis bag method, while the effects of iRGD on liposome targeting were evaluated through laser confocal microscopy. The CCK-8 assay was used to investigate the toxicity and cell growth effects of this system on 4T1 breast cancer cells and HUVEC vascular endothelial cells. A subcutaneous breast cancer tumor model was established to evaluate the tumor-killing effects and therapeutic mechanism of the newly developed liposomes. Results: The liposome carrier exhibited a regular morphology, with a particle size of 232.16 ± 19.82 nm, as indicated by dynamic light scattering (DLS), and demonstrated low toxicity to both HUVEC and 4T1 cells. With an encapsulation efficiency of 41.82 ± 5.67%, the carrier exhibited a slow release pattern in vitro after STING loading. Targeting results indicated that iRGD modification enhanced the system's ability to target 4T1 cells. The iRGD-STING-PFP@liposomes group demonstrated significant tumor growth inhibition in the subcutaneous breast cancer mouse model with effective activation of the immune system, resulting in the highest populations of matured dendritic cells (71.2 ± 5.4%), increased presentation of tumor-related antigens, promoted CD8+ T cell infiltration at the tumor site, and enhanced NK cell activity. Conclusions: The iRGD-STING-PFP@liposomes targeted drug delivery system effectively targets breast cancer cells, providing a new strategy for breast cancer immunotherapy. These findings indicate that iRGD-STING-PFP@liposomes could successfully deliver STING agonists to tumor tissue, trigger the innate immune response, and may serve as a potential platform for targeted immunotherapy. [ABSTRACT FROM AUTHOR]

The article discusses the use of mesenchymal stromal cells (MSCs) in limiting house dust mite extract-induced mixed granulocytic lung inflammation in an experimental asthma model. The study found that intranasal administration of adipose tissue-derived MSCs reduced lung leukocyte infiltration, eosinophil and neutrophil counts, and altered gene expression related to inflammation. Additionally, MSCs were effective in reducing subepithelial collagen deposition and changing T effector cell responses. Further research is needed to fully understand the long-term effects of MSC transplantation in non-T2-driven asthmatic inflammation. [Extracted from the article]

The article explores the use of probiotic bacteria and butyrate in preventing allergic airway and gut inflammation in humanized mice. The study found that a specific probiotic formulation, BactoFlor® 10/20, and butyrate effectively prevented inflammation in the gut and lungs of mice with allergen-induced inflammation. The protective effect was linked to the modulation of regulatory T cells and the mucosal epithelium. The research highlights the potential of probiotics in managing allergic diseases in the gastrointestinal and respiratory tracts. [Extracted from the article]

Peptide-based anticancer vaccines have shown some efficacy in generating cancer-specific immune responses in various cancer studies, but clinical success is limited, one of the reasons is due to its prone degradation and weak immunogenicity. So some tumor epitope peptide vaccines often require coupling or forming fusion proteins with corresponding protein carriers to enhance their stability and immunogenicity. Given the scarcity of validated carriers for clinical trials, there is an urgent requirement for the development of novel protein carrier. Our previous work has demonstrated that VEGF165b mutant could be used as an effective immunization adjunct to enhance anti-tumor immune response. By analyzing and evaluating the gene structure of VEGF, we speculated that mVEGF165b has the potential to be utilized as a tumor peptide vaccine carrier. An mVEGF165b-MUC1 chimeric tumor vaccine was produced by fusing the MUC1 peptide （(MUC1, a T-cell epitope dominant peptide from Mucin1） to the C-terminus of mVEGF165b, expressing the fusing protein in pichia yeast, followed by purification with a HiTrap heparin affinity chromatography column. We found that immunizing mice with mVEGF165b-MUC1 fusion protein induced high-titer antibodies against VEGF in a preventive context, which in turn reduced the proportion of Tregs and further stimulated mice to produce T-cell responses specific to mucin1. The high-titer VEGF antibody stimulated by mVEGF165b also promoted tumor blood vessel maturation and facilitated T-cell infiltration. In conclusion，immunized with mVEGF165b-MUC1 protein are beneficial for eliciting immune responses targeting Mucin1, mVEGF165b have the potential to be utilized as a peptide tumor vaccine carrier. • mVEGF165b can be used as a protein carrier for the MUC1 peptide. • High anti-VEGF antibody titers induced by mVEGF165b-MUC1 decreased immunosuppression by reducing the proportion of Tregs. • The decreased immunosuppression augmented the immune response induced by the peptide vaccine from Mucin-1. [ABSTRACT FROM AUTHOR]

Introduction: Influenza A is a virus from the Orthomixoviridae family responsible for high lethality rates and morbidity, despite clinically proven vaccination strategies and some anti-viral therapies. The eicosanoid Lipoxin A4 (LXA4) promotes the resolution of inflammation by decreasing cell recruitment and pro-inflammatory cytokines release, but also for inducing activation of apoptosis, efferocytosis, and macrophage reprogramming. Objective: Here, we evaluated whether a synthetic lipoxin mimetic, designated AT-01-KG, would improve the course of influenza A infection in a murine model. Method: Mice were infected with influenza A/H1N1 and treated with AT-01-KG (1.7 μg/kg/day, i.p.) at day 3 post-infection. Results: AT-01-KG attenuated mortality, reducing leukocyte infiltration and lung damage at day 5 and day 7 post-infection. AT-01-KG is a Formyl Peptide Receptor 2 (designated FPR2/3 in mice) agonist, and the protective responses were not observed in fpr2/3 −/− animals. In mice treated with LXA4 (50 μg/kg/day, i.p., days 3–6 post-infection), at day 7, macrophage reprogramming was observed, as seen by a decrease in classically activated macrophages and an increase in alternatively activated macrophages in the lungs. Furthermore, the number of apoptotic cells and cells undergoing efferocytosis was increased in the lavage of treated mice. Treatment also modulated the adaptive immune response, increasing the number of T helper 2 cells (Th2) and regulatory T (Tregs) cells in the lungs of the treated mice. Conclusion: Therefore, treatment with a lipoxin A4 analog was beneficial in a model of influenza A infection in mice. The drug decreased inflammation and promoted resolution and beneficial immune responses, suggesting it may be useful in patients with severe influenza. [ABSTRACT FROM AUTHOR]

Kirsten rat sarcoma virus (KRAS)-G12C inhibition causes remodeling of the lung tumor immune microenvironment and synergistic responses to anti-PD-1 treatment, but only in T cell infiltrated tumors. To investigate mechanisms that restrain combination immunotherapy sensitivity in immune-excluded tumors, we used imaging mass cytometry to explore cellular distribution in an immune-evasive KRAS mutant lung cancer model. Cellular spatial pattern characterization revealed a community where CD4+ and CD8+ T cells and dendritic cells were gathered, suggesting localized T cell activation. KRAS-G12C inhibition led to increased PD-1 expression, proliferation, and cytotoxicity of CD8+ T cells, and CXCL9 expression by dendritic cells, indicating an effector response. However, suppressive regulatory T cells (Tregs) were also found in frequent contact with effector T cells within this community. Lung adenocarcinoma clinical samples showed similar communities. Depleting Tregs led to enhanced tumor control in combination with anti-PD-1 and KRAS-G12C inhibitor. Combining Treg depletion with KRAS inhibition shows therapeutic potential for increasing antitumoral immune responses. [ABSTRACT FROM AUTHOR]

Pannexins (PANXs) are expressed by mammalian immune and nonimmune cells and promote the export of many <1-kDa small molecules, at steady-state or in response to disease. In mice and humans, PANX1 is a crucial regulator of lung adaptive immunity, controlling conventional and regulatory CD4+ T cell immune responses to lung allergens. PANX1 supports the development of mouse CD8+ T cell effector and memory responses, via the export of extracellular ATP and induction of lactate recycling to induce full CD8+ T cell activation. PANX3 on murine bone marrow (BM) osteoblasts maintains BM plasma cells by its ATP-releasing function. Pannexin (PANX) channels mediate the release of small molecules (e.g., ATP) and play a fundamental role in the export of metabolites in healthy or disease contexts. Recent advances define some of the roles of PANXs in T and B cell responses in vivo and highlight the importance of these channels in the regulation of adaptive immune responses. The development of mammalian adaptive (i.e., B and T cell-mediated) immune responses is tightly controlled at transcriptional, epigenetic, and metabolic levels. Signals derived from the extracellular milieu are crucial regulators of adaptive immunity. Beyond the traditionally studied cytokines and chemokines, many other extracellular metabolites can bind to specialized receptors and regulate T and B cell immune responses. These molecules often accumulate extracellularly through active export by plasma membrane transporters. For example, mammalian immune and non-immune cells express pannexin (PANX)1–3 channels on the plasma membrane, which release many distinct small molecules, notably intracellular ATP. Here, we review novel findings defining PANXs as crucial regulators of T and B cell immune responses in disease contexts such as cancer or viral infections. [ABSTRACT FROM AUTHOR]

Background: Neuromyelitis optica spectrum disorders (NMOSD) are autoimmune conditions that affect the central nervous system. The contribution of peripheral abnormalities to the disease's pathogenesis is not well understood. Methods: To investigate this, we employed a multi-omics approach analyzing blood samples from 52 NMOSD patients and 46 healthy controls (HC). This included mass cytometry, cytokine arrays, and targeted metabolomics. We then analyzed the peripheral changes of NMOSD, and features related to NMOSD's disease severity. Furthermore, an integrative analysis was conducted to identify the distinguishing characteristics of NMOSD from HC. Additionally, we unveiled the variations in peripheral features among different clinical subgroups within NMOSD. An independent cohort of 40 individuals with NMOSD was utilized to assess the serum levels of fibroblast activation protein alpha (FAP). Results: Our analysis revealed a distinct peripheral immune and metabolic signature in NMOSD patients. This signature is characterized by an increase in monocytes and a decrease in regulatory T cells, dendritic cells, natural killer cells, and various T cell subsets. Additionally, we found elevated levels of inflammatory cytokines and reduced levels of tissue-repair cytokines. Metabolic changes were also evident, with higher levels of bile acids, lactates, triglycerides, and lower levels of dehydroepiandrosterone sulfate, homoarginine, octadecadienoic acid (FA[18:2]), and sphingolipids. We identified distinctive biomarkers differentiating NMOSD from HC and found blood factors correlating with disease severity. Among these, fibroblast activation protein alpha (FAP) was a notable marker of disease progression. Conclusions: Our comprehensive blood profile analysis offers new insights into NMOSD pathophysiology, revealing significant peripheral immune and metabolic alterations. This work lays the groundwork for future biomarker identification and mechanistic studies in NMOSD, highlighting the potential of FAP as a marker of disease progression. [ABSTRACT FROM AUTHOR]

Context.--: Regulatory T-cell (Treg) detection in peripheral blood, based on flow cytometry, is invaluable for diagnosis and treatment of immune-mediated diseases. However, there is a lack of reliable methods to verify the performance, which is pivotal toward standardization of the Tregs assay. Objective.--: To conduct standardization studies and verify the performance of 3 commercially available reagent sets for the Tregs assay based on flow cytometry and agreement analysis for Treg detection across the different reagent sets. Design.--: The analytical performance of Tregs assay using reagent sets supplied by 3 manufacturers was evaluated after establishing the gating strategy and determining the optimal antibody concentration. Postcollection sample stability was evaluated, as well as the repeatability, reproducibility, reportable range, linearity, and assay carryover. Agreement between the different assays was assessed via Bland-Altman plots and linear regression analysis. The relationship between the frequency of CD4+CD25+CD127low/- Tregs and CD4+CD25+Foxp3+ Tregs was evaluated. Results.--: The postcollection sample stability was set at 72 hours after collection at room temperature. The accuracy, repeatability, reproducibility, and accuracy all met the requirements for clinical analysis. Excellent linearity, with R2 ≥0.9 and no assay carryover, was observed. For reportable range, a minimum of 1000 events in the CD3+CD4+ gate was required for Tregs assay. Moreover, the results for Tregs labeled by antibodies from the 3 manufacturers were in good agreement. The percentage of CD4+CD25+CD127low/- Tregs was closely correlated with CD4+CD25+Foxp3+ Tregs. Conclusions.--: This is the first study to evaluate systematically the measurement performance of Tregs in peripheral blood by flow cytometry, which provides a practical solution to verifying the performance of flow cytometry-based immune monitoring projects in clinical practice. [ABSTRACT FROM AUTHOR]

Objective: We analyzed the impact of different inhalant allergens on T-lymphocyte subsets in patients diagnosed with bronchial asthma. Methods: The study included 57 bronchial asthma patients and 22 healthy controls. Asthma patients were categorized into dust mite, animal hair, pollen, and mold groups. Flow cytometry was used to measure the cells in the case group and control group. These T-lymphocyte subset markers were evaluated among patients with bronchial asthma caused by different allergens as well as between the case group and control group. Results: Peripheral blood CD4+ T-cells, CD8+ T-cells, CD4/CD8 ratio, and Th17/Treg ratios were all higher in the case group than in the control group (p < 0.05). Peripheral blood T-lymphocyte subsets were compared among the four groups, and it was found that there were statistical differences in the Th17/Treg ratio among the four groups (p < 0.05). There were no significant differences observed among the four groups in terms of CD3+ cells, CD4+ cells, CD8+ cells, Th1 cells, Th2 cells, Th17 cells, Treg cells, Th9 cells, and Th22 cells. Further pairwise comparison was made, and the results suggested that the peripheral blood Th17/Treg ratio in the pollen mixed group was lower than that in the dust mite mixed group, animal hair mixed group, and mold mixed group (p < 0.05). Conclusion: Patients with bronchial asthma show varied T-lymphocyte subset responses to different inhalant allergens. Elevated CD4+ T cells and Th17 cells in peripheral blood could indicate asthma risk. However, small sample size may introduce bias to these findings. [ABSTRACT FROM AUTHOR]

Alopecia areata is a common autoimmune disorder characterized by non-scarring hair loss on the scalp or other hair-bearing surface. In recent years, Janus kinase (JAK) inhibitors have shown promise in the treatment of alopecia areata by disrupting the signaling pathways involved in immune-mediated hair follicle damage. However, some patients with alopecia areata exhibit insufficient responses to JAK inhibitors. This review aims to explore the predictive factors for poor responses to JAK inhibitors in patients with alopecia areata and to discuss alternative treatment strategies in such cases. Patients with a longer duration of the current episode and higher baseline severity are at an increased risk of inadequate JAK inhibitor responses. Oral administration rather than topical application, and extended treatment durations, correlate with a favorable response. Notably, the poor response to JAK inhibitors in alopecia areata may be related to the amount and functional depletion of regulatory T cells resulting from an augmented T helper-2-type immune response. For patients with poor responses to JAK inhibitors, treatment adjustments may include increasing the dosage, extending the treatment duration, combination therapies, or switching to alternative JAK inhibitors. For patients with atopic comorbidities or psychological problems, it is important to select corresponding treatment options to optimize patient outcomes. Further research is needed to establish more reliable predictors and improve overall patient care. [ABSTRACT FROM AUTHOR]

Immunotherapy has emerged as a promising therapeutic approach for cancer treatment by harnessing the immune system to target cancer cells. However, the efficacy of immunotherapy is hindered by the tumor microenvironment (TME), comprising regulatory T cells (Tregs), macrophages, myeloid-derived suppressor cells (MDSCs), neutrophils, soluble factors (TGF-β, IL-35, IL-10), and hypoxia. These components interact with inhibitory receptors (IRs) on T cells, leading to alterations in T cell transcriptomes, epigenomes, and metabolism, ultimately resulting in T cell exhaustion and compromising the effectiveness of immunotherapy. T cell exhaustion occurs in two phases: pre-exhaustion and exhaustion. Pre-exhausted T cells exhibit reversibility and distinct molecular properties compared to terminally exhausted T cells. Understanding these differences is crucial for designing effective interventions. This comprehensive review summarizes the characteristics of pre-exhausted and exhausted T cells and elucidates the influence of TME components on T cell activity, transcriptomes, epigenomes, and metabolism, ultimately driving T cell exhaustion in cancer. Additionally, potential intervention strategies for reversing exhaustion are discussed. By gaining insights into the mechanisms underlying T cell exhaustion and the impact of the TME, this review aims to inform the development of innovative approaches for combating T cell exhaustion and enhancing the efficacy of immunotherapy in cancer treatment. PLAIN LANGUAGE SUMMARY: The immune system normally attacks any external factor or abnormal cell in the body, however, sometimes abnormal cells such as cancerous cells can escape the immune system and form a tumor. A class of therapy known as immunotherapy relies on reinforcing the immune system in fighting cancerous cells. However, it cannot have a sustained effect because due to chronic exposure to cancerous cells, T cells, which are the pivotal cells in anti-cancer immunity, gradually lose their activity, a phenomenon known as T cell exhaustion. Exhausted T cells differ from normal T cells in metabolism, transcriptomes, and epigenomes and express different molecules, consequently leading to their dysfunction. By having a comprehensive knowledge of exhausted T cells properties and the factors that give rise to exhaustion, scientists can think of new strategies to make immunotherapy more robust. [ABSTRACT FROM AUTHOR]

Multiple sclerosis is a demyelinating neurodegenerative disease, and its animal model, experimental autoimmune encephalomyelitis (EAE), exhibits immunological and clinical similarities. The study aimed to examine mechanisms underlying therapeutic effects of mesenchymal stem cell administration in EAE. C57BL/6 mice were separated into control and treatment groups (T1, T2, and T3); EAE was induced in all animals. Clinical examinations were conducted daily, and on 25th day, animals were sacrificed, and spinal cord was stained for histological analysis. Additionally, spleen cell proliferation assay, assessments of cytokine, and gene expression in both spinal cord and spleen cells were performed. The results indicated a significant reduction in clinical symptoms among treatment groups compared to control group. Histological analyses revealed decreased infiltration of lymphocytes into the spinal cord and reduced demyelinated areas in treatment groups compared to control group. Cytokine production of IL‐10, TGF‐β, and IL‐4 were significantly enhanced and IFN‐γ and TNF‐α in treatment groups were decreased relative to control group. Also, gene expression of CTLA‐4, PD‐1, IL‐27, and IL‐33 indicated a significant increase in treatment groups. The administration of MSCs significantly improved clinical symptoms, attenuated inflammation, and reduced spinal cord demyelination in EAE, suggesting a potential protective effect on disease progression. [ABSTRACT FROM AUTHOR]

Background: Psoriasis is an immune‐mediated inflammatory skin disorder with a multifaceted pathogenesis. Immune dysregulation and immune cell dysfunction are among the mechanisms involved. TEA domain family member 4 (TEAD4) is suggested to play a role in psoriasis development. TEAD4 expression in keratinocytes may have a chemotactic effect and could disturb the function of FOXP3‐positive T lymphocytes. This study aimed to evaluate the expressions of TEAD4 and FOXP3 in lesional, nonlesional psoriatic, and healthy skin and assess the clinical impact of their expression. Methods: This case–control study included 32 cases with psoriasis vulgaris and 32 control groups. Hematoxylin and eosin‐stained slides were examined to evaluate the histopathological findings. Moreover, other sections were immunohistochemically stained with FOXP3 and TEAD4. Results: FOXP3 was expressed in inflammatory cells in 56.5, 37.5, and 12.5% of lesional, nonlesional, and healthy skin, whereas it was entirely negative in the keratinocytes. TEAD4 was expressed in keratinocytes in 93.7 and 46.9% of lesional and nonlesional skin, while negative in healthy skin. Significant differences were observed between their lesional, nonlesional, and healthy skin expressions. Furthermore, FOXP3 expression in lesional skin was significantly associated with early onset (P = 0.016), low PASI score (P = 0.002), mild psoriasis (P = 0.007), and axial affection (P = 0.022), while TEAD4 expression was associated with progressive course (P = 0.032), high PASI score (P = 0.002), severe psoriasis (P = 0.001), severe inflammation (P = 0.001), and progressive course (P = 0.017). Conclusion: TEAD4 expression was higher in lesional than nonlesional skin and absent in healthy skin, suggesting a role in psoriasis development. TEAD4 expression was also associated with severe and progressive psoriasis. This may be mediated by the downregulation of FOXP3 and dysfunction of Treg cells. TEAD4 could serve as a promising therapeutic target in psoriasis. [ABSTRACT FROM AUTHOR]

Chronic HCV infection results in abnormal immunological alterations, which are not fully normalized after viral elimination by direct-acting antiviral (DAA) treatment. Herein, we longitudinally examined phenotypic, transcriptomic, and epigenetic alterations in peripheral blood regulatory T (Treg) cells from patients with chronic HCV infection before, during, and after DAA treatment. Patients with chronic genotype 1b HCV infection who achieved sustained virologic response by DAA treatment and age-matched healthy donors were recruited. Phenotypic characteristics of Treg cells were investigated through flow cytometry analysis. Moreover, the transcriptomic and epigenetic landscapes of Treg cells were analyzed using RNA sequencing and ATAC-seq (assay for transposase-accessible chromatin with sequencing) analysis. The Treg cell population – especially the activated Treg cell subpopulation – was expanded in peripheral blood during chronic HCV infection, and this expansion was sustained even after viral clearance. RNA sequencing analysis revealed that viral clearance did not abrogate the inflammatory features of these Treg cells, such as Treg activation and TNF signaling. Moreover, ATAC-seq analysis showed inflammatory imprinting in the epigenetic landscape of Treg cells from patients, which remained after treatment. These findings were further confirmed by intracellular cytokine staining, demonstrating that Treg cells exhibited inflammatory features and TNF production in chronic HCV infection that were maintained after viral clearance. Overall, our results showed that during chronic HCV infection, the expanded Treg cell population acquired inflammatory features at phenotypic, transcriptomic, and epigenetic levels, which were maintained even after successful viral elimination by DAA treatment. Further studies are warranted to examine the clinical significance of sustained inflammatory features in the Treg cell population after recovery from chronic HCV infection. During chronic HCV infection, several immune components are altered both quantitatively and qualitatively. The recent introduction of direct-acting antivirals has led to high cure rates. Nevertheless, we have demonstrated that inflammatory features of Treg cells are maintained at phenotypic, transcriptomic, and epigenetic levels even after successful DAA treatment. Further in-depth studies are required to investigate the long-term clinical outcomes of patients who have recovered from chronic HCV infection. [Display omitted] • Increased Tregs persist in patients with chronic HCV after DAA-induced viral clearance. • DAA-induced HCV clearance does not abrogate inflammatory features of Tregs. • HCV clearance does not reverse inflammatory imprinting in the epigenome of Tregs. • Increased TNF+ Tregs persist in patients with chronic HCV after viral clearance. [ABSTRACT FROM AUTHOR]

High stemness index scores are associated with poor survival in patients with lung cancer. Studies on the mRNA expression-based stemness index (mRNAsi) are typically conducted using tumor tissues; however, mRNAsi-related expression signatures based on cell-free RNA (cfRNA) are yet to be comprehensively investigated. The present study aimed to elucidate the gene expression profiles of tumor stemness in lung cancer tissues and corresponding cfRNAs in blood, and to assess their links with immune infiltration. Tumor tissue, paracancerous tissue, peripheral blood and lymph node samples were collected from patients with stage I-III non-small cell lung cancer and RNA sequencing was performed. The TCGAbiolinks package was used to calculate the mRNAsi for each of these four types of sample. Weighted gene co-expression network analysis and differentially expressed gene analyses were performed to investigate mRNAsi-related genes, and pathway enrichment analysis was performed using the Kyoto Encyclopedia of Genes and Genomes (KEGG) orthology-based annotation system. In addition, the STAR-Fusion tool was used to detect fusion variants, and CIBERSORT was used to analyze the correlations of stemness signatures in tissues and blood with immune cell infiltration. The mRNAsi values in peripheral blood and lymph nodes were found to be higher than those in cancer tissues. 'Hematopoietic cell lineage' was the only KEGG pathway enriched in mRNAsi-related genes in both lung cancer tissues and peripheral blood. In addition, the protein tyrosine phosphatase receptor type C associated protein gene was the only gene commonly associated with the mRNAsi in these two types of sample. The expression of mRNAsi-related genes was increased in the dendritic and Treg cells in tumor tissues, but was elevated in Treg and CD8 cells in the blood. In conclusion, cfRNAs in the blood exhibit unique stemness signatures that have potential for use in the diagnosis of lung cancer. [ABSTRACT FROM AUTHOR]

Infantile refractory diarrhea presents after first few days of life leading to intestinal insufficiency. It is a diagnostic challenge due to varied etiologies like food senstive enteropathy, anatomical defects and dysmotility disorders, transport and enzymatic defects, pancreatic malabsorption - cystic fibrosis (CF), primary epithelial causes like microvillus inclusion disease (MVID), tufting enteropathy and heparan sulfate deficiency, immunodeficiencies, metabolic diseases and autoimmune enteropathy. It is refractory to treatment making the patient dependent on total parenteral nutrition. Immune dysregulation, polyendocrinopathy, enteropathy, X-linked syndrome (IPEX), is one of the rarest causes of intractable diarrhea. It occurs due to mutations in the FOXP3 gene, leading to dysfunction of T-regulatory cells and is characterised by diarrhoea, diabetes, and dermatitis. We aim to evaluate various causes of infantile refractory chronic diarrhea, and to present one such case of IPEX syndrome from this part of the world due to mutation not been reported in literature so far. [ABSTRACT FROM AUTHOR]