NKT Cells Research Articles

Early-life antibiotic exposure aggravate the metabolic dysfunction-associated steatotic liver disease associated hepatocellular carcinoma.

Metabolic dysfunction-associated steatotic liver disease (MASLD) asscociated hepatocellular carcinoma (HCC) is becoming a growing concern in global healthcare. The early-life gut microbiota plays a crucial role in maintaining healthy. However, the impact of early-life gut microbiota dysbiosis on the advancement of MASLD-HCC remains inadequately understood. In the present study, we investigated the role of early-life gut microbiota in the development of MASLD-HCC in streptozotocin and high-fat diet (STZ-HFD) induced mouse model. We recorded the body weight and lifespan, and dynamically monitored the level of alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), total cholesterol (T-CHO) and blood glucose in the serum monthly. In addition, we examined various immune cells present in the liver, such as T cells, B cells, NK cells, NKT cells, αβT cells, γδT cells, macrophage and MDSC cells by flow cytometry and conducted liquid chromatography mass spectrometry (LC-MS) based analysis on liver tissue from control and early-life antibiotic exposure mice (early-Abx) MASLD-HCC mice. We found that early-Abx mice suffered from more severe tumor burden and further confirmed that hepatocytes and immune cells were all disturbed. Importantly, early-life antibiotic exposure alters the liver metabolic profiling especially glycerophospholipids and lipid accumulation. Furthermore, mice exposed to antibiotics in early-life showed disturbances in glucose metabolism and developed insulin resistance. Collectively, our findings revealed that early-life antibiotic exposure accelerated the progression of MASLD-HCC by impairing the hepatocytes, immune homeostasis and metabolites persistently, highlighting the importance of the early-life microbiota in the development of MASLD-HCC.

Harnessing Chimeric Antigen Receptor-engineered Invariant Natural Killer T Cells: Therapeutic Strategies for Cancer and the Tumor Microenvironment.

Chimeric antigen receptor (CAR)-engineered T (CAR-T) cell therapy has emerged as a revolutionary approach for cancer treatment, especially for hematologic cancers. However, CAR-T therapy has some limitations, including cytokine release syndrome (CRS), immune cellassociated neurologic syndrome (ICANS), and difficulty in targeting solid tumors and delivering allogeneic cell therapy due to graft-versus-host disease (GvHD). Therefore, it is important to explore other cell sources for CAR engineering. Invariant natural killer T (iNKT) cells are a potential target, as they possess powerful antitumor ability and do not recognize mismatched major histocompatibility complexes (MHCs) and protein antigens, thus avoiding the risk of GvHD. CAR-engineered iNKT (CAR-iNKT) cell therapy offers a promising new approach to cancer immunotherapy by overcoming the drawbacks of CAR-T cell therapy while retaining potent antitumor capabilities. This review summarizes the current CAR-iNKT cell products, their functions and phenotypes, and their potential for off-the-shelf cancer immunotherapy.

Safety and tolerability of CRX100, an NKT cell therapy combined with tumor-specific oncolytic vaccinia virus, among patients with recurrent, platinum-resistant ovarian cancer

Safety and tolerability of CRX100, an NKT cell therapy combined with tumor-specific oncolytic vaccinia virus, among patients with recurrent, platinum-resistant ovarian cancer

Crucial immunological roles of the invasion front in innate and adaptive immunity in cervical cancer.

The immunostimulatory actions of innate and adaptive immune responses play a crucial role in the cancer-immunity cycle. Although cervical cancer (CC) exhibits a high recurrence rate, the relation with lymphocytes in the tumor tissue have not been analyzed. We analyzed NKT, NK, and T cells, not only in peripheral blood (PB), but also tumor tissue through histological analysis from 23 patients with CC collected before treatment. A correlation of them between PB and the tumor tissue were assessed. We detected functional NKT and NKG2Dhi NK cells and effector CD4+ Tregs in PB. In the tumor, we detected the infiltration of LAG-3+ TIM-3+ CD4+ and CD8+ T cells rather than NK cells particularly in the invasion front (IF) by fluorescent multiplex immunohistochemistry. The heatmap and correlation analysis revealed that LAG-3+ TIM-3+ CD8+ T cells are highly associated with CD69+ CD103- exhausted CD8+ T cells. We identified the statistical relationship between CD4+Tregs in PB and the number of LAG-3+ TIM-3+ CD4+ T cells in the IF, which may be related to recurrence in patients with CC. LAG-3+ TIM-3+ T cells located in the IF may play a key role in regulation of the tumor immune microenvironment.

Hyperlipidemia interferes with the behavior of variant NKT cells

Abstract Background NKT cells significantly influence atherosclerosis development. However, inconsistent findings on the function of the NKT cells and the invariant subset in atherosclerosis remains a challenge. Moreover, there is no clarity on the role and phenotype of the variant (vNKT) subset in atherosclerosis. Purpose To understand the role of the vNKT subsets in HFD-induced atherosclerosis. Methods We extracted the data for meta-analysis to understand the role of the whole NKT and iNKT cells in atherosclerosis. PRISMA guidelines were followed for the meta-analysis. In addition, C57BL/6 mice (WT) were fed with HFD for 20 weeks from 6-8 weeks of age. vNKTs were identified as CD3+NK1.1+CD1d-tetramer- within the CD3+NK1.1+ NKT cell population in both liver and spleen by flow cytometry. Intracellular cyotkines staining was performed. Statistical differences inthe means of two groups are calculated by two-tailed Student’s t-test with nonparametric Mann-Whitney tests. P-value<0.05 was considered significant. All data represented as mean±SEM. Results The NKT cell numbers increased significantly in the spleen, lymph nodes, blood, and liver in the HFD-fed mice fed from 1.5 to 24 weeks in Apoe-/-, Ldlr-/- in comparison to wild-type mice (SMD, 2.51 [95% CI, 1.42, 3.61]). Contrary to this, the iNKT cell numbers and the iNKT TCR gene expression levels, decreased significantly in the HFD-fed mice (SMD, -2.04 [95% CI, -3.34, -0.75]). The reduction in iNKT cell numbers is also supported by the clinical data from the AMI patients when compared to healthy controls [SMD = -1.81, 95% CI = -2.89, -0.74] (Figure 1). In HFD-fed C57BL/6 hyperlipidemic mice, significantly increased levels of total cholesterol (HFD vs Chow; 226.5±29.66 vs 118.5±10.56 mg/dL, n=4) and LDLc (44.56±11.96 vs 16.69±1.13 mg%, n=4) was observed. The number of vNKTs in the liver was significantly increased by 46% (HFD vs Chow 28.35±2.28 vs 19.41±1.36, n=6-7) (Figure 2A). However, the CD8+ vNKTs were significantly decreased by 68.6% in the liver (4.72±0.99 vs 15.06±0.96) and the CD4+ vNKTs decreased more than two times in the HFD-fed WT liver (7.39±0.76 vs 18.28±0.36) (Figure 2B). Also, the intracellular IFN-γ+ vNKT cells doubled in their numbers in the HFD-fed spleen (14.31±1.39 vs 6.367±0.87) compared to the chow-fed mice (Figure 2C). Conclusion(s) Meta-analysis revealed dual nature of the NKT cells and its invariant subsets in atherosclerosis, since the whole NKTs increase whereas the iNKTs decrease in number. The vNKT subset actively participates in immune modulation in the HFD-induced hyperlipidemia by increasing their number, as well as by differentially regulating CD8 and CD4 co-receptors between chow and HFD. HFD induced a pro-inflammatory nature in the splenic vNKTs but not in liver vNKTs, that in turn may aggravate other immune cells. This data confirms the dual nature of the NKT subsets and reveals a crucial systemic involvement of vNKT cells in the progression of dyslipidemia.

The Absence of Thyroid-Stimulating Hormone Receptor Expression on Natural Killer T Cells: Implications for the Immune–Endocrine Interaction

The expression of thyroid-stimulating hormone receptor (TSHR) has been documented on various immune cells, including B lymphocytes, T lymphocytes, Natural Killer (NK) cells, monocytes, and dendritic cells (DCs). Natural Killer T (NKT) cells serve as a crucial link between innate and adaptive immunity, playing significant roles in immunological interactions and autoimmune diseases. The aim of the present study was to evaluate the presence of TSHR on NKT cells. Our research involved patients with thyroid disease, as well as healthy controls. Peripheral blood mononuclear cells (PBMCs) and, thereafter, NKT cells were isolated from 86 patients with benign nodular thyroid disease with and without autoimmune thyroid disease (AITD) (28 and 56 cases, respectively), and TSHR expression was analyzed using fluorescence-activated cell sorting (FACS). In order to confirm the results, the reverse-transcription polymerase chain reaction (RT-PCR) method was used in cells obtained from healthy individuals. Our findings obtained with application of the FACS method revealed that TSHR is not expressed on NKT cells in either AITD or non-AITD patients, though TSHR was detected in the total PBMC population (TSHR+ cells 2.77%). The absence of TSHR on NKT cells was further confirmed with RT-PCR in healthy individuals (p < 0.0001). These results questioned the previously suggested direct influence of NKT cells on AITD development.

Innate immune response in COVID-19: single-cell multi-omics profile of NK lymphocytes in a clinical case series

BackgroundCOVID-19 pandemic caused by the Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) represents the biggest global health emergency in recent decades. The host immune response to SARS-CoV-2 seems to play a key role in disease pathogenesis and clinical manifestations, with Natural Killer (NK) lymphocytes being among the targets of virus-induced regulation.MethodsThis study performed a single-cell multi-omics analysis of transcripts and proteins of NK lymphocytes in COVID-19 patients, for the characterization of the innate immunological response to infection. NK cells were isolated from peripheral blood samples collected from adult subjects divided into 3 study groups: (1) non-infected subjects (Naïve group, n = 3), (2) post COVID-19 convalescent subjects (Healed group, n = 3) and (3) patients that were vaccinated against SARS-CoV-2 (Vaccine group, n = 3). Cells were then analysed by the BD Rhapsody System for the single-cell multi-omics investigation of transcriptome and membrane proteins.ResultsThe bioinformatic analysis identified 5 cell clusters which differentially expressed gene/protein markers, defining NK cell subsets as “Active NK cells” and “Mature NK cells”. Calculating the relative proportion of each cluster within patient groups, more than 40% of the Naïve group cell population was found to belong to Mature NKs, whereas more than 75% of the Vaccine group cell population belonged to the cluster of Active NKs. Regarding the Healed group, it seemed to show intermediate phenotype between Active and Mature NK cells. Differential expression of specific genes, proteins and signaling pathways was detected comparing the profile of the 3 experimental groups, revealing a more activated NK cell phenotype in vaccinated patients versus recovered individuals.ConclusionsThe present study detected differential expression of NK cell markers in relation to SARS-CoV-2 infection and vaccine administration, suggesting the possibility to identify key molecular targets for clinical-diagnostic use of the individual response to viral infection and/or re-infection.

State of the Field: Cytotoxic Immune Cell Responses in C. neoformans and C. deneoformans Infection.

Cryptococcus neoformans is an environmental pathogen that causes life-threatening disease in immunocompromised persons. The majority of immunological studies have centered on CD4+ T-cell dysfunction and associated cytokine signaling pathways, optimization of phagocytic cell function against fungal cells, and identification of robust antigens for vaccine development. However, a growing body of literature exists regarding cytotoxic cells, specifically CD8+ T-cells, Natural Killer cells, gamma/delta T-cells, NK T-cells, and Cytotoxic CD4+ T-cells, and their role in the innate and adaptive immune response during C. neoformans and C. deneoformans infection. In this review, we (1) provide a comprehensive report of data gathered from mouse and human studies on cytotoxic cell function and phenotype, (2) discuss harmonious and conflicting results on cellular responses in mice models and human infection, (3) identify gaps of knowledge in the field ripe for exploration, and (4) highlight how innovative immunological tools could enhance the study of cytotoxic cells and their potential immunomodulation during cryptococcosis.

Dysregulation of T cell response in the pathogenesis of inflammatory bowel disease.

Inflammatory bowel disease (IBD), comprised of Crohn's disease (CD) and ulcerative colitis (UC), are gut inflammatory diseases that were earlier prevalent in the Western Hemisphere but now are on the rise in the East, with India standing second highest in the incidence rate in the world. Inflammation in IBD is a cause of dysregulated immune response, wherein helper T (Th) cell subsets and their cytokines play a major role in the pathogenesis of IBD. In addition, gut microbiota, environmental factors such as dietary factors and host genetics influence the outcome and severity of IBD. Dysregulation between effector and regulatory T cells drives gut inflammation, as effector T cells like Th1, Th17 and Th9 subsets Th cell lineages were found to be increased in IBD patients. In this review, we attempted to discuss the role of different Th cell subsets together with other T cells like CD8+ T cells, NKT and γδT cells in the outcome of gut inflammation in IBD. We also highlighted the potential therapeutic candidates for IBD.

Effective anti-tumor immune responses are orchestrated by immune cell partnership network that functions through tissue homeostatic pathways, not direct cytotoxicity.

The liver hosts a diverse array of immune cells that play pivotal roles in both maintaining tissue homeostasis and responding to disease. However, the precise contributions of these immune cells in the progression of nonalcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC) remain unclear. Utilizing a systems immunology approach, we reveal that liver immune responses are governed by a dominant-subdominant hierarchy of ligand-receptor-mediated homeostatic pathways. In healthy individuals, inflammatory immune responses operate within these pathways, challenging the notion of the liver as a purely tolerogenic organ. Chronic consumption of a Western diet (WD) disrupts hepatocyte function and reconfigures immune interactions, resulting in hepatic stellate cells (HSCs), cancer cells, and NKT cells driving 80% of the immune activity during NAFLD. In HCC, 80% of immune response involves NKT cells and monocytes collaborating with hepatocytes and myofibroblasts to restore disrupted homeostasis. Interestingly, dietary correction during NAFLD yields nonlinear outcomes: tumor progression coincides with the failure of mounting homeostatic immune responses, whereas tumor prevention is associated with sustained immune responses, predominantly orchestrated by monocytes. These monocytes actively target fibroblasts and myofibroblasts, creating a tumor-suppressive microenvironment. Notably, only 5% of T cells displayed apoptosis-inducing activity, selectively contributing to the turnover of hepatic stromal cells, particularly myofibroblasts and fibroblasts. Our findings suggest that effective anti-tumor immune responses in the liver are primarily mediated by immune cells sustaining tissue homeostasis, rather than relying on direct cytotoxic mechanisms.

Multi-scale transcriptomics reveals that specific tumor cells promote lung adenocarcinoma metastasis through crosstalk with the microenvironment

Most advanced lung adenocarcinoma (LUAD) patient deaths are attributed to metastasis. However, the complete understanding of the metastatic mechanism in LUAD remains elusive. Single-cell RNA-seq (scRNA-seq), spatial RNA-seq (stRNA-seq) and bulk RNA-seq of primary LUAD were integrated to investigate metastatic driver genes, cell–cell interactions, and spatial colocalization of cells and ligand-receptor pairs. A lung adenocarcinoma metastasis risk scoring model (LMRS) was established to estimate the risk of metastasis in LUAD. Forty-two metastasis driver genes were identified and tumor epithelial cells were classified into two subtypes. Epithelial cell subclass characterized by susceptibility to metastasis are referred to as Epithelial_LM, and the remaining as Epithelial_LL. Epithelial_LM subtype has intimate ligand-receptor interactions with inflammatory endothelial cells (iendo), inflammatory cancer-associated fibroblasts (iCAF), and NKT cells. Epithelial_LM cells have a spatial colocalization relationship with these three types of cells. The LMRS was established and its efficacy was verified in bulk RNA-seq. We identified a subclass of epithelial cells prone to metastasis and demonstrated the contribution of inflammatory stromal cells and NKT cells in facilitating tumor metastasis.Graphical

Superior antitumor immune response achieved with proton over photon immunoradiotherapy is amplified by the nanoradioenhancer NBTXR3

Recent findings suggest that immunoradiotherapy (IRT), combining photon radiotherapy (XRT) or proton radiotherapy (PRT) with immune checkpoint blockade, can enhance systemic tumor control. However, the comparative efficacy of XRT and PRT in IRT remains understudied. To address this, we compared outcomes between XRT + αPD1 and PRT + αPD1 in murine αPD1-resistant lung cancer (344SQR). We also assessed the impact of the nanoparticle radioenhancer NBTXR3 on both XRT + αPD1 and PRT + αPD1 for tumor control and examined the tumor immune microenvironment using single-cell RNA sequencing (scRNAseq). Additionally, mice cured by NBTXR3 + PRT + αPD1 were rechallenged with three lung cancer cell lines to evaluate memory antitumor immunity. PRT + αPD1 showed superior local tumor control and abscopal effects compared to XRT + αPD1. NBTXR3 + PRT + αPD1 significantly outperformed NBTXR3 + XRT + αPD1 in tumor control, promoting greater infiltration of antitumor lymphocytes into irradiated tumors. Unirradiated tumors treated with NBTXR3 + PRT + αPD1 had more NKT cells, CD4 T cells, and B cells, with fewer Tregs, than those treated with NBTXR3 + XRT + αPD1. NBTXR3 + PRT + αPD1 also stimulated higher expression of IFN-γ, GzmB, and Nkg7 in lymphocytes, reduced the TGF-β pathway, and increased tumor necrosis factor alpha expression compared to NBTXR3 + XRT + αPD1. Moreover, NBTXR3 + PRT + αPD1 resulted in greater M1 macrophage polarization in both irradiated and unirradiated tumors. Mice achieving remission through NBTXR3 + PRT + αPD1 exhibited a robust memory immune response, effectively inhibiting growth of subsequent tumors from three distinct lung cancer cell lines. Proton IRT combined with NBTXR3 offers enhanced tumor control and survival rates over photon-based treatments in managing αPD1-resistant lung cancer, indicating its potential as a potent systemic therapy.Graphical

Synthesis of sulfoCy5‐ and sulfoCy7‐αGalCer Probes as Chemical Tools for Investigating the Uptake of Liposomal αGalCer Conjugates by Antigen Presenting Cells

α‐Galactosylceramide (αGalCer) is a synthetic glycolipid that, when loaded into the CD1d receptor of antigen presenting cells, activates iNKT cells to coordinate the generation of both innate and adaptive immune responses. In vaccines, the αGalCer adjuvant is generally delivered in liposomes, but interestingly, little is known about the intracellular fate of αGalCer–antigen conjugates resulting in the absence of clear “design rules” for this type of compounds and their formulations. To unravel the uptake mechanism of liposomal αGalCer conjugates and understand the fate of its components, we synthesized sulfoCy7–αGalCer 1 and sulfoCy5–αGalCer 2. The fluorescent probes were obtained from a linker–functionalized αGalCer, which was then modified with sulfoCy7/sulfoCy5. After formulation in liposomes, the cellular presentation was studied in a murine dendritic cell line using fluorescence imaging and flow cytometry. Imaging indicates that liposomes loaded with sulfoCy5–αGalCer are taken up by DC2.4 cells in a heterogeneous and concentration‐dependent manner. Additionally, fluorescence antibody staining confirms that αGalCer is ultimately presented by CD1d receptors, but importantly is cleaved from sulfoCy5 before reaching the cell surface. These results validate our synthetic probes as useful in mechanistic studies of the uptake of αGalCer–antigen conjugates as shown here for DC2.4 cells.

Causal relationships between immunophenotypes, plasma metabolites, and temporomandibular disorders based on Mendelian randomization

While numerous studies have underscored the implication of immune cells and metabolites in temporomandibular disorders (TMD), conclusive evidence for causality remains elusive. Consequently, our aim is to explore the causal connections between immunophenotypes and plasma metabolites in relation to TMD employing a bidirectional Mendelian randomization (MR) approach. Summary statistics data on 731 immunophenotypes (n = 3757) and 1091 plasma metabolites (n = 8299) were obtained from comprehensive genome-wide association studies (GWAS), while TMD data (5668 cases and 205,355 controls) were acquired from the FinnGen Consortium. Bidirectional MR analyses and a two-step MR approach assessed causal relationships and potential intermediaries. Various corrections and sensitivity analyses were utilized to assess the robustness of the findings. Two immunophenotypes and seven metabolites were significantly associated with TMD risk. Specifically, Alpha-hydroxyisovalerate mediated the link between CD33 on CD33dim HLA DR + CD11b + and TMD (β = 0.034, P = 5.95 × 10–5), while CD8 on NKT cells mediated the causal relationship between 5-acetylamino-6-formylamino-3-methyluracil levels and TMD (β = 0.069, P = 5.11 × 10–5). Our findings revealed the causal relationships between immunophenotypes and plasma metabolites on TMD from a genetic perspective, potentially aiding in TMD prevention.

TIPE2 protein restrains invariant NKT activation and protects against immune-mediated hepatitis in mice.

Concanavalin A (ConA) administration induces a rapid and severe liver injury in mice, and invariant natural killer T (iNKT) cells are recognized to be the key effector cells in this process. However, the underlying regulatory mechanisms are not well defined. We found that iNKT cells constitutively expressed TIPE2 (Tumor necrosis factor-α-induced protein 8-like 2, or TNFAIPL2). Genetic TIPE2 ablation strongly sensitized mice to ConA-induced hepatitis, accompanied with hyperactivation of iNKT cells. Moreover, Tipe2-/- mice were also more susceptible to α-galactosylceramide (αGalCer)-induced liver injury, with elevated serum ALT level and enhanced proinflammatory cytokine production. CD1d signaling blockade or iNKT cell elimination through antibodies reduced the effect of TIPE2 deficiency on liver injury. Mechanistic studies revealed that TIPE2 in iNKT cells functioned as a negative regulator, limiting iNKT cell activity and cytokine production through PIP3- AKT/mTOR pathway. TIPE2-mediated protection from liver injury was further validated by the administration of adeno-associated viruses expressing TIPE2, which effectively ameliorated ConA-induced hepatic injury. However, TIPE2 was dispensable in two other liver injury models, including D-GalN/LPS and APAP-induced hepatitis. Our findings reveal a new role of TIPE2 in the attenuation of iNKT cell-mediated hepatic injury. We propose that TIPE2 serves as an important regulator of immune homeostasis in the liver, and might be exploited for the therapeutic treatment of autoimmune liver diseases.

Feline eosinophilic sclerosing fibroplasia associated with T-/natural killer-cell lymphoma.

Feline eosinophilic sclerosing fibroplasia (FESF) is a proliferative, inflammatory disease of the gastrointestinal tract and other sites, uncommonly diagnosed in the cat. This entity of uncertain etiology typically presents as a progressive mass lesion, mimicking a neoplastic process. In this case series, we present 17 cases of FESF associated with intralesional lymphoma. Histologic and immunohistochemical characterization of this unique lymphoma revealed that the neoplastic lymphocytes were immunopositive for CD56 and/ or CD3, suggesting a natural killer cell, natural killer T-cell, or T-cell origin. This case series represents the first description of this lymphoma subtype, for which the term eosinophilic sclerosing lymphoma is proposed.

Exploring CD26-/lo subpopulations of lymphocytes in asthma phenotype and severity: A novel CD4+ T cell subset expressing archetypical granulocyte proteins.

Asthma pathology may induce changes in naïve/memory lymphocyte proportions assessable through the evaluation of surface CD26 (dipeptidyl peptidase 4/DPP4) levels. Our aim was to investigate the association of asthma phenotype/severity with the relative frequency of CD26-/lo, CD26int and CD26hi subsets within different lymphocyte populations. The proportion of CD26-/lo, CD26int and CD26hi subsets within CD4+ effector T cells (Teff), total CD4- lymphocytes, γδ-T cells, NK cells and NKT cells was measured in peripheral blood samples from healthy (N = 30) and asthma (N = 119) donors with different phenotypes/severities by flow cytometry. We performed K-means clustering analysis and further characterised the CD4+CD26-/lo Teff cell subset by LC-MS/MS and immunofluorescence. Cluster analysis including clinical and flow cytometry data resulted in four groups, two of them with opposite inflammatory profiles (neutrophilic vs. eosinophilic). Neutrophilic asthma presented reduced CD4-CD26hi cells, which negatively correlated with systemic inflammation. Eosinophilic asthma displayed a general expansion of CD26-/lo subsets. Specifically, CD4+CD26-/lo Teff expansion was confirmed in asthma, especially in atopic patients. Proteomic characterisation of this subset with a TEM/TEMRA phenotype revealed upregulated levels of innate (e.g. MPO and RNASE2) and cytoskeleton/extracellular matrix (e.g. MMP9 and ACTN1) proteins. Immunofluorescence assays confirmed the presence of atypical proteins for CD4+ T cells, and an enrichment in 'flower-like' nuclei and MMP9/RNASE2 levels in CD4+CD26-/lo Teff compared to CD4+ T lymphocytes. There is an association between CD26 levels in different lymphocyte subsets and asthma phenotype/severity. CD4+CD26-/loTEMRA cells expressing innate proteins specific to eosinophils/neutrophils could be determinant in sustaining long-term inflammation in adult allergic asthma.

Decreased CD3+CD56+ Natural Killer T Lymphocytes and Increased Human Leukocyte Antigen-DR+ Cells in the Inflamed Area of Pouchitis in Ulcerative Colitis Patients.

Pouchitis is an inflammatory condition that affects the ileal pouch during ileal pouch-anal anastomosis surgery. Despite its clinical significance, precise immunological mechanisms underlying pouchitis remain unclear. This study aimed to investigate the lymphocyte profile in the ileal pouch of patients with pouchitis compared to those with familial adenomatous polyposis (FAP) and ulcerative colitis without pouchitis using flow cytometry and immunohistochemical techniques. We prospectively analyzed endoscopic biopsy specimens from the ileal pouches of 15 patients and categorized them into three groups: FAP, ulcerative colitis with an inflammation-free pouch (UC-I), and ulcerative colitis with ulcers and/or erosions in the pouch (UC-UE). Flow cytometry was used to assess various T-lymphocyte markers, including cluster of differentiation (CD) 4, CD8, CD56, and human leukocyte antigen (HLA)-DR. Immunohistochemistry was performed to visualize the spatial distribution of CD3+, CD56+, and HLA-DR+ cells in the pouch mucosa. We observed significantly reduced CD56+/CD3+ and CD8+/CD3+ ratios in the UC-UE group compared to those in the FAP group, indicating a disruption in natural killer T-cell populations. Immunohistochemical analysis revealed that the spatial distribution of lymphocytes differed among the non-inflamed mucosa, dense lymphocyte infiltration, and lymphoid follicles, with these components frequently intermingling. CD56 + cells were less abundant in areas with dense lymphocyte infiltration, whereas HLA-DR+ cells were more abundant. Our study revealed a decrease in CD56+ natural killer T cells and an increase in HLA-DR+-activated T cells in areas with dense lymphocyte infiltration, suggesting an association between these cells and pouchitis in ulcerative colitis. The distinct patterns observed in non-inflamed mucosa, areas with dense lymphocyte infiltration, and lymphoid follicles underscore the need for further analyses of these three segments to elucidate the immunological mechanisms underlying pouchitis.

Eed-dependent histone modification orchestrates the iNKT cell developmental program alleviating liver injury.

Polycomb repressive complex 2 (PRC2) is an evolutionarily conserved epigenetic modifier responsible for tri-methylation of lysine 27 on histone H3 (H3K27me3). Previous studies have linked PRC2 to invariant natural killer T (iNKT) cell development, but its physiological and precise role remained unclear. To address this, we conditionally deleted Eed, a core subunit of PRC2, in mouse T cells. The results showed that Eed-deficient mice exhibited a severe reduction in iNKT cell numbers, particularly NKT1 and NKT17 cells, while conventional T cells and NKT2 cells remained intact. Deletion of Eed disrupted iNKT cell differentiation, leading to increased cell death, which was accompanied by a severe reduction in H3K27me3 levels and abnormal expression of Zbtb16, Cdkn2a, and Cdkn1a. Interestingly, Eed-deficient mice were highly susceptible to acetaminophen-induced liver injury and inflammation in an iNKT cell-dependent manner, highlighting the critical role of Eed-mediated H3K27me3 marks in liver-resident iNKT cells. These findings provide further insight into the epigenetic orchestration of iNKT cell-specific transcriptional programs.

Fully Synthetic TF-Based Self-Adjuvanting Vaccine Simultaneously Triggers iNKT Cells and Mincle and Protects Mice against Tumor Development.

The Thomsen-Friedenreich (TF) antigen has proven to be a promising target for developing novel therapeutic cancer vaccines. Here, a new strategy that TF antigen covalently coupled with KRN7000 and vizantin was developed. The resulting three-component vaccine KRN7000-TF-vizantin simultaneously triggers invariant natural killer T (iNKT) cells and macrophage-inducible C-type lectin (Mincle) signaling pathways, eliciting much stronger TF-specific immune responses than glycoprotein vaccine TF-KLH/alum and the corresponding two-component conjugate vaccines TF-KRN7000 and TF-vizantin. The analysis of IgG isotypes and the secretion of cytokines revealed that KRN7000-TF-vizantin induced Th1/Th2 mixed immune responses, where Th1 was dominant. In vivo experiments demonstrated that KRN7000-TF-vizantin increased the survival rate and survival time of tumor-challenged mice, and surviving mice rejected further tumor attacks without any additional treatment. This work demonstrates that covalently coupled KRN7000 and vizantin could serve as a promising TF-based vaccine carrier for antitumor immune therapy, and KRN7000-TF-vizantin features great potential to be a vaccine candidate.