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Coexistence of hepatitis B surface antigen (HBsAg) and hepatitis B surface antibody (anti-HBs) has been observed in some chronic hepatitis B (CHB) patients (DP patients), but the clinical outcomes and comprehensive characterization of immune micro-environmental changes for this specific population remain inconclusive. In this study, we retrospectively analyze the prognosis of 305 patients in Foshan City, Guangdong Province, China, and also investigated the molecular immunology changes in HBsAg and anti-HBs double positive CHB patients (DP group), CHB patients who had recovered from IFN-ɑ treatment (RP group), and healthy controls (HC group) using T cell receptor (TCR) and B cell receptor (BCR) immune repertoire sequencing. Our findings revealed that 22.30% of DP patients were diagnosed with severe liver disease. Immune repertoire sequencing revealed significant skewing in the diversities of T cell receptor β-chain (TRB) and immunoglobulin heavy chain (IGH) in the DP group compared to the RP group. Unique V(D)J gene combinations, such as IGHV1-18/IGHD3-22/IGHJ5, IGHV1-8/IGHD6-13/IGHJ3, and IGHV1-8/IGHD6-19/IGHJ3, as well as TRBV12-3/TRBD1/TRBJ1-5 and TRBV11-2/TRBD2/TRBJ2-1, exhibited distinct utilization patterns in the DP group. Moreover, the top ten most utilized amino acid motifs in the complementarity determining region 3 (CDR3) of TRB in the DP group showed significant differences from those in the RP group. Notably, motifs such as "xxxYDSSGYx" and "AREx" in the IGH CDR3s were selectively prevalent in the DP group. These findings are expected to provide evidence supporting the poor clinical prognosis of DP patients and offer new insights into the distinct immune micro-environmental changes of this group. [ABSTRACT FROM AUTHOR]

The body's immune response plays a critical role in defending against external or foreign antigens while also preserving tolerance to self‐antigens. This equilibrium, referred to as immune homeostasis, is paramount for overall health. The regulatory mechanisms governing the maintenance of this delicate immune balance are notably complex. It is currently accepted that immune tolerance is a dynamic outcome regulated by multiple factors, including central and peripheral mechanisms. Its induction or elimination plays a significant role in autoimmune diseases, organ transplantation, and cancer therapy, markedly impacting various major diseases in modern clinical practice. Overall, our current understanding of immune tolerance is still very limited. In this review article, we summarized the main mechanisms that have been known to mediate immune tolerance so far, including endogenous immune tolerance, adaptive immune tolerance, other immune tolerance mechanisms, and the homeostasis of immune tolerance, identified the key factors that regulate immune tolerance, and provided new clues for immune system recovery in many autoimmune diseases, organ transplantation, and tumor therapy. [ABSTRACT FROM AUTHOR]

Introduction: The coronavirus disease 2019 (COVID-19) global pandemic has been the most severe public health emergency since 2019. Currently, the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been the most dominant. The most prominent symptom of SARS-CoV-2 infection is respiratory. Meanwhile, the fatality of COVID-19 was mainly from pneumonia. However ,in patients with SARS-CoV-2 infection who have pneumonia and those who do not, the differences in the immune repertoire still require further investigation. Methods: We conducted seven-chain adaptome immune repertoire analyses on patients with SARS-CoV-2 Omicron infection, both with and without pulmonary infiltration. Results: Patients with pulmonary infiltration exhibit lymphopenia, a decreased proportion of the overall TCR repertoire alongside an increased BCR repertoire, reduced IGHD and IGHM isotype expression, a shorter mean CDR3 length for TRG, and a longer mean length for TRD, as well as diminished clonality and diversity in the TCR/BCR repertoire. Meanwhile, patients with pulmonary infiltration have distinct V-J gene usage and unique CDR3 signature, as well as BCR class switch recombination pattern. Finally, prior vaccination triggered less BCR IGHM/IGHD somatic hypermutation response, preserved the diversity of the entire adaptive immune repertoire, and provided clinical protection against severe or critical conditions following Omicron infection. Discussion: We report a unique, comprehensive adaptive immune system signature in patients with pulmonary infiltration, which may serve as potential immunological biomarkers and therapeutic targets. [ABSTRACT FROM AUTHOR]

Background: T cells form one of the key pillars of adaptive immunity. Using their surface bound T cell antigen receptors (TCRs), these cells screen millions of antigens presented by major histocompatibility complex (MHC) or MHC-like molecules. In other protein families, the dynamics of protein-protein interactions have important implications for protein function. Case studies of TCR:class I peptide-MHCs (pMHC-Is) structures have reported mixed results on whether the binding interfaces undergo conformational change during engagement and no robust statistical quantification has been done to generalise these results. Thus, it remains an open question of whether movement occurs in the binding interface that enables the recognition and activation of T cells. Methods: In this work, we quantify the conformational changes in the TCR:pMHC-I binding interface by creating a dataset of 391 structures, comprising 22 TCRs, 19 MHC alleles, and 79 peptide structures in both unbound (apo) and bound (holo) conformations. Results: In support of some case studies, we demonstrate that all complementarity determining region (CDR) loops move to a certain extent but only CDR3α and CDR3β loops modify their shape when binding pMHC-Is. We also map the contacts between TCRs and pMHC-Is, generating a novel fingerprint of TCRs on MHC molecules and show that the CDR3α tends to bind the N-terminus of the peptide and the CDR3β tends to bind the C-terminus of the peptide. Finally, we show that the presented peptides can undergo conformational changes when engaged by TCRs, as has been reported in past literature, but novelly show these changes depend on how the peptides are anchored in the MHC binding groove. Conclusions: Our work has implications in understanding the behaviour of TCR:pMHC-I interactions and providing insights that can be used for modelling Tcell antigen specificity, an ongoing grand challenge in immunology. [ABSTRACT FROM AUTHOR]

Post-translational ubiquitination is an essential mechanism for the regulation of protein stability and function, which contributes to the regulation of the immune system. Cbl, an E3 ubiquitin ligase, is particularly well-characterized in the context of T and NK cell signaling, where it serves as a key regulator of receptor downstream signaling events and as a modulator of cell activation. Cbl promotes the proteasomal degradation of TCR/CD3 subunits as well as the protein kinases Fyn and Lck in T cells. Additionally, the scaffold protein linker for activation of T cells (LAT) is a universal target for Cbl-mediated ubiquitination and degradation in both T and NK cells. Recent findings suggest that CrkII-mediated ubiquitination and degradation of C3G by Cbl during early T cell activation may also be relevant to NK cell signaling. Given its role in modulating immune responses and its manageable impact on autoimmunity, Cbl is being investigated as a target for cancer immunotherapy. This review explores the ubiquitin ligase activity of Cbl and its implications for CAR T and NK cell immunotherapies. [ABSTRACT FROM AUTHOR]

Isolation of tumor-specific T cells and their antigen receptors (TCRs) from malignant pleural effusions (MPE) may facilitate the development of TCR-transduced adoptive cellular immunotherapy products for advanced lung cancer patients. However, the characteristics and markers of tumor-specific T-cells in MPE are largely undefined. To this end, to establish the phenotypes and antigen specificities of CD8+ T cells, we performed single-cell RNA and TCR sequencing of samples from three advanced lung cancer patients. Dimensionality reduction on a total of 4,983 CD8+ T cells revealed 10 clusters including naïve, memory, and exhausted phenotypes. We focused particularly on exhausted T cell clusters and tested their TCR reactivity against neoantigens predicted from autologous cancer cell lines. Four different TCRs specific for the same neoantigen and one orphan TCR specific for the autologous cell line were identified from one of the patients. Differential gene expression analysis in tumor-specific T cells relative to the other T cells identified CXCL13, as a candidate gene expressed by tumor-specific T cells. In addition to expressing CXCL13, tumor-specific T cells were present in a higher proportion of T cells co-expressing PDCD1(PD-1)/TNFRSF9(4-1BB). Furthermore, flow cytometric analyses in advanced lung cancer patients with MPE documented that those with high PD-1/4-1BB expression have a better prognosis in the subset of 57 adenocarcinoma patients (p =.039). These data suggest that PD-1/4-1BB co-expression might identify tumor-specific CD8+ T cells in MPE, which are associated with patients' prognosis. (233 words) [ABSTRACT FROM AUTHOR]

Myasthenia gravis (MG) is the most frequent immune‐mediated neurological disorder, characterized by fluctuating muscle weakness. Specific recognition of self‐antigens by T‐cell receptors (TCRs) and B‐cell receptors (BCRs), coupled with T–B cell interactions, activates B cells to produce autoantibodies, which are critical for the initiation and perpetuation of MG. The immune repertoire comprises all functionally diverse T and B cells at a specific time point in an individual, reflecting the essence of immune selectivity. By sequencing the nucleotide sequences of TCRs and BCRs, it is possible to track individual T‐ and B‐cell clones. This review delves into the generation of autoreactive TCRs and BCRs in MG and comprehensively examines the applications of immune repertoire sequencing in understanding disease pathogenesis, developing diagnostic and prognostic markers and informing targeted therapies. We also discuss the current limitations and future potential of this approach. [ABSTRACT FROM AUTHOR]

Introduction: Adoptive cell therapy using TCR-engineered T-cells is one of the most effective strategies against tumor cells. The TCR T-cell approach has been well tested against a variety of blood neoplasms but is yet to be deeply tested against solid tumors. Among solid tumors, cancer-testis antigens are the most prominent targets for tumor-specific therapy, as they are usually found on cells that lie behind blood-tissue barriers. Methods: We have employed a novel efficient protocol for MAGE-A3-specific Tcell clonal expansion, performed single-cell multi-omic analysis of the expanded T-cells via BD Rhapsody, engineered a selected T-cell receptor into a lentiviral construct, and tested it in an in vitro LDH-cytotoxicity test. Results and discussion: We have observed a 191-fold increase in the MAGE-A3-specific T-cell abundance, obtained a dominant T-cell receptor via single-cell multi-omic BD Rhapsody data analysis in the TCRscape bioinformatics tool, and observed potent cytotoxicity of the dominant-clonotype transduced TCR T-cells against a MAGE-A3-positive tumor. We have demonstrated the efficiency of our Tcell enrichment protocol in obtaining potent anti-tumor T-cells and their T-cell receptors, especially when paired with the modern single-cell analysis methods. [ABSTRACT FROM AUTHOR]

T lymphocytes play a vital role in the immune‐inflammatory response following a stroke. However, the specific mechanisms behind the contrasting functions of T cells in the brain and peripheral tissues after a stroke remain unclear and require further investigation. T‐cell receptors (TCRs) are essential in controlling how T lymphocytes develop and become active. This study aims to gain a deeper understanding of the biological function of T lymphocytes by analyzing the TCR repertoire in patients who have experienced an acute ischemic stroke (AIS). High‐throughput TCR sequencing was conducted on peripheral blood samples from 25 AIS patients and 10 healthy controls. We compared the percentage of T cells and the characteristics of the TCR repertoire, specifically focusing on the recombination of V(D)J gene fragments and the diversity of the complementarity determining region 3 (CDR3) of the Vβ gene. Additionally, this study analyzed the potential biological significance of the skewed TCR repertoire in AIS patients. In patients with AIS, the proportion of circulating lymphocytes (LY%) decreased while the systemic immune‐inflammatory index (SII) increased compared to healthy controls. The average number of TCR read pairs decreased, corresponding with the presence of lymphopenia. However, the recombination of V(D)J gene fragments, the number of CDR3 clonotypes, and the diversity of CDR3 was elevated in the peripheral blood of AIS patients. Furthermore, the increased number of CDR3 amino acid or nucleotide clonotypes was negatively correlated with neurologic deficits but positively correlated with AIS patients' systemic immune condition and functional outcomes. Our findings suggest that both immunosuppression and enhanced antigen‐specific T‐cell response may exist in the periphery of the AIS patients. Further investigation into the mechanisms underlying these opposing changes may lead to the discovery of novel targets to reverse immunosuppression or mitigate the detrimental effects of T cells in the lesioned brain of AIS patients. [ABSTRACT FROM AUTHOR]

T-cell engagers (TCEs) represent a promising therapeutic strategy for various cancers and autoimmune disorders. These bispecific antibodies act as bridges, connecting T-cell receptors (TCRs) to target cells (either malignant or autoreactive) via interactions with specific tumour-associated antigens (TAAs) or autoantigens to form trimeric synapses, or trimers, that co-localise T-cells with target cells and stimulate their cytotoxic function. Bispecific TCEs are expected to exhibit a bell-shaped dose-response curve, with a defined optimal TCE exposure for maximizing trimer formation. The shape of the dose-response is determined by a non-trivial interplay of binding affinities, exposure and antigens expression levels. Furthermore, excessively low binding to the TCR may reduce efficacy, but mitigate risk of overstimulating cytokine secretion or induce effector cell exhaustion. These inevitable trade-off highlights the importance of quantitatively understanding the relationship between TCE concentration, target expression, binding affinities, and trimer formation. We utilized a mechanistic target engagement model to show that, if the TCE design parameters are close to the recommended ranges found in the literature, relative affinities for TCR, TAA and target expression levels have qualitatively different, but predictable, effects on the resulting dose-response curve: higher expression levels shift the curve upwards, higher antigen affinity shifts the curve to the left, and higher TCR affinity shifts the curve upwards and to the left. [ABSTRACT FROM AUTHOR]

[Display omitted] The invariant TCR ζ/CD247 homodimer is crucial for TCR/CD3 expression and signaling through its 3 immunoreceptor tyrosine-based activation motifs (ITAMs). Homozygous null mutations in CD247 lead to immunodeficiency, while carriers exhibit 50% reduced surface CD3. It is unclear whether carriers of other CD247 variants show dominant-negative effects. We sought to analyze and model the potential impact on T-cell receptor (TCR) expression and function of heterozygous nonsense CD247 mutations found in patients with signs of immunodeficiency or autoimmunity. Jurkat T cells, either wild-type (WT) or CRISPR/Cas9-edited CD247-deficient (ZKO), were lentivirally transduced with WT CD247 or mutations ablating 1 (Q142X), 2 (Q101X), or 3 (Q70X) ITAMs. Three patients from unrelated families were studied. Two heterozygous nonsense CD247 mutations were identified (p.Y152X and p.Q101X), which affected ITAM-3 and ITAM-2 and ITAM-3, respectively. Both mutations were associated with low surface CD3 expression and normal intracellular CD247 levels using a transmembrane-specific antibody, but very low intracellular CD247 levels using an ITAM-3–specific one, suggesting the presence of truncated variants in T cells. Transduction of the mutations lacking 1, 2, or 3 ITAMs into ZKO cells could not restore normal surface CD3 expression (only 60%, 22%, and 10%, respectively), whereas in WT cells, normal surface CD3 expression was reduced (to 39%, 19%, and 9% of normal levels), and both effects were dependent on ITAM number. All 6 transfectants showed reduced CD69 induction (25% to 50%), indicating that they were unable to signal downstream properly, neither isolated nor associated with WT CD247. Our results suggest that CD247 variants lacking ITAMs due to nonsense, but not null, mutations are defective for normal TCR assembly and exert a dominant-negative effect on TCR expression and signaling in vitro. This, in turn, may correlate with clinical features in vivo. [ABSTRACT FROM AUTHOR]

Sepsis affects 25 million children per year globally, leading to 2.9 million deaths and substantial disability in survivors. Extensive characterization of interactions between the host and bacteria in children is required to design novel preventive and therapeutic strategies tailored to this age group. Vγ9Vδ2 T cells are the first T cells generated in humans. These cells are defined by the expression of Vγ9Vδ2 T‐cell receptors (TCRs, using the TRGV9 and TRDV2 gene segments), which react strongly against the prototypical bacterial phosphoantigen HMBPP. We investigated this reactivity by analyzing the TCR δ (TRD) repertoire in the blood of 76 children (0–16 years) with blood culture‐proven bacterial sepsis caused by HMBPP‐positive Escherichia coli or by HMBPP‐negative Staphylococcus aureus or by HMBPP‐negative Streptococcus pneumoniae. Strikingly, we found that S. aureus, and to a lesser extent E. coli but not S. pneumoniae, shaped the TRDV2 repertoire in young children (<2 years) but not in older children or adults. This dichotomy was due to the selective expansion of a fetal TRDV2 repertoire. Thus, young children possess fetal‐derived Vγ9Vδ2 T cells that are highly responsive toward specific bacterial pathogens. [ABSTRACT FROM AUTHOR]

Mechanical force has repeatedly been highlighted to be involved in T cell activation. However, the biological significance of mechanical force for T cell receptor signaling remains under active consideration. Here, guided by theoretical analysis, we provide a perspective on how mechanical forces between a T cell and an antigen-presenting cell can influence the bond of a single T cell receptor major histocompatibility complex during early T cell activation. We point out that the lifetime of T cell receptor bonds and thus the degree of their phosphorylation which is essential for T cell activation depends considerably on the T cell receptor rigidity and the average magnitude and frequency of an applied oscillatory force. Such forces could be, for example, produced by protrusions like microvilli during early T cell activation or invadosomes during full T cell activation. These features are suggestive of mechanical force being exploited by T cells to advance self-nonself discrimination in early T cell activation. [ABSTRACT FROM AUTHOR]

The demand for cost–effective materials for thick film resistors has driven the exploration of alternative functional materials to replace the traditionally used ruthenium oxides. This study investigates the synthesis and properties of copper–substituted La 0.5 Sr 0.5 CoO 3 (La 0.5 Sr 0.5 Co 1-x Cu x O 3 , LSCCu, x = 0.02–0.10) ceramics as a potential economical substitute. The crystal structure, electrical performance, and sintering behavior of LSCCu with varying Cu2+ contents were characterized through solid–state reactions and first–principles simulations. The results indicate that the perovskite structure is maintained with increasing Cu2+, while the densification temperature, crystallinity, and conductivity decrease. Moreover, Cu2+ substitution reduced the DOS across the Fermi level and weakened the electron transport in LSCCu. The sample with x = 0.06 exhibited a promising conductivity of 2609 S/cm after sintering at 1150 °C, comparable to commercial thick film resistor materials. The temperature coefficient of resistance (TCR) of LSCCu showed a metallic behavior with a low value of 1148 ppm/°C for the x = 0.06 sample. Additionally, the LSCCu ceramics possess good long–term stability and frequency stability of resistance. These findings suggest that LSCCu ceramics are a promising economical material for thick film resistor applications. [ABSTRACT FROM AUTHOR]

Unsaturated fatty acids (UFA) are crucial for T‐cell effector functions, as they can affect the growth, differentiation, survival, and function of T cells. Nonetheless, the mechanisms by which UFA affects T‐cell behavior are ill‐defined. Therefore, we analyzed the processing of oleic acid, a prominent UFA abundantly present in blood, adipocytes, and the fat pads surrounding lymph nodes, in CD4+ T cells. We found that exogenous oleic acid increases proliferation and enhances the calcium flux response upon CD3/CD28 activation. By using a variety of techniques, we found that the incorporation of oleic acid into membrane lipids, rather than regulation of cellular metabolism or TCR expression, is essential for its effects on CD4+ T cells. These results provide novel insights into the mechanism through which exogenous oleic acid enhances CD4+ T‐cell function. [ABSTRACT FROM AUTHOR]

The magnetic and electric evolution with the substitution level of Co element has been investigated in Mn3−xCoxAgN. The DC magnetic measurements demonstrate that the substitution of Co for Mn enhances the antiferromagnetic (AFM) interaction and weakens the magnetic irreversibility at low temperature. The strengthening of AFM order in Mn3−xCoxAgN has been attributed to the enhanced Co–Mn AFM interaction and weakened Co–N–Mn ferromagnetic (FM) interaction. Additionally, with the gradual increase of Co content, the temperature coefficient of resistivity (TCR) in paramagnetic (PM) region changes from a positive one to a negative one gradually. When x=0.15, the TCR value is only ∼5ppm/K, which is one magnitude smaller than that of conventional standard resistor materials. The negative TCR phenomenon is closely associated with the Co-element-induced lattice disorder, which leads to the weak localization of conduction electrons. [ABSTRACT FROM AUTHOR]

Element-modified La 0.67 Ca 0.33 MnO 3 (LCMO) ceramics have been a major research subject in the past decades due to their various electromagnetic properties and potential applications in infrared detection and magnetic storage devices. However, its electromagnetic transport mechanism has not been fully elucidated and its properties need to be further optimized for practical applications. Here, we report the effect of Ni2+ doping on the structural, magnetic, the temperature coefficient of resistivity (TCR) and magnetoresistance (MR) properties of La 0.67 Ca 0.33 Mn 1- x Ni x O 3 (LCMNO) ceramics. All samples were synthesized by the sol-gel method and were in pure phase. XRD refinement results show a decrease in lattice constants and cell volume of LCMNO ceramics with increasing Ni2+ content. The XPS study confirms the reduction of the Mn3+/Mn4+ ratio and indicates that oxygen vacancies occur in LCMNO ceramics due to the Ni2+ doping. Curie-Weiss fitting results suggest ferromagnetic superexchange coupling between Ni2+ and Mn3+(4+) ions. The electrical transport properties of LCMNO ceramics were further investigated using the spin polaron hopping model in the high temperature range and the various competing scattering mechanisms in the low temperature range. In addition, double resistivity peak behavior is observed at x = 0.04 and 0.05. Furthermore, the TCR of the LCMNO ceramics increased to 45.4 %·K−1 (x = 0.01), while the MR increased to 67.9 % (x = 0.03), respectively. Our studies contribute to a better understanding of the electromagnetic properties of LCMNO ceramics. [ABSTRACT FROM AUTHOR]

Due to outstanding advantages such as lightweight, good toughness, low cost and simple forming process, reduced graphene oxide (rGO) films have attracted considerable attention in temperature sensing and electro heating fields. In this study, the difference in the microstructure, bond types, mechanical and electrical properties of rGO films reduced at different temperatures are analysed to explore the influence of reduction degree on temperature sensing and heating performance of rGO films. The results indicate that oxygen-containing functional groups including C-O and C=O in graphene oxide (GO) films decrease dramatically at 200 ℃, and the main bonding type of carbon atoms transfers from C-C to C=C. When the reduction temperature rises to 600 ℃, rGO films still retain some oxygen-containing functional groups with a C/O ratio of 7.18, while the composition of rGO films reduced at 800 ℃ approaches to graphene. With the increase of reduction degree, electrical resistivity of rGO films shows a significant decrease. However, the outgassing of oxygen atoms disrupts the interlayer dense structure, leading to gradual reduction in tensile strength. At the reduction temperature of 600 ℃, the resistance-temperature curve exhibits excellent linear relationship with a temperature coefficient of resistance (TCR) value of -1.60×10-3/℃ at room temperature. Under 24 V DC driving voltage, rGO films reduced at 600 ℃ and 800 ℃ reach 242 ℃ and 367 ℃, respectively. However, due to the loose and cracked interlayer structure, there happens a noticeable fluctuation in the heating temperature curve of rGO films reduced at 800 ℃. Therefore, rGO films reduced at 600 ℃ are proven to be more suitable for heating and temperature sensing. [ABSTRACT FROM AUTHOR]

The size and condition of the peripheral CD4 T cell population determine the capacity of the immune response. Under homeostatic conditions, the size of the peripheral CD4 T cell population is maintained through turnover and survival. However, the underlying mechanisms remain inadequately understood. Here, we observed a significant decrease in the percentage of CD4 T cells in the periphery following the targeted deletion of the Paxbp1 gene in mouse T cells. In the absence of Paxbp1, naïve CD4 T cells displayed reduced surface interleukin‐7 receptor levels and a decreased capacity to respond to survival signals mediated by interleukin‐7. In addition, naïve CD4 T cells deficient in Paxbp1 demonstrated impaired T cell antigen receptor signalling, compromised cell cycle entry, decreased proliferation, and increased apoptosis following stimulation, all of which contributed to the reduction in the number of peripheral CD4 T cells. Therefore, our study highlights the indispensable role of Paxbp1 in maintaining peripheral CD4 T cell homeostasis. [ABSTRACT FROM AUTHOR]

IntroductionThe coronavirus disease 2019 (COVID-19) global pandemic has been the most severe public health emergency since 2019. Currently, the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been the most dominant. The most prominent symptom of SARS-CoV-2 infection is respiratory. Meanwhile, the fatality of COVID-19 was mainly from pneumonia. However ,in patients with SARS-CoV-2 infection who have pneumonia and those who do not, the differences in the immune repertoire still require further investigation.MethodsWe conducted seven-chain adaptome immune repertoire analyses on patients with SARS-CoV-2 Omicron infection, both with and without pulmonary infiltration.ResultsPatients with pulmonary infiltration exhibit lymphopenia, a decreased proportion of the overall TCR repertoire alongside an increased BCR repertoire, reduced IGHD and IGHM isotype expression, a shorter mean CDR3 length for TRG, and a longer mean length for TRD, as well as diminished clonality and diversity in the TCR/BCR repertoire. Meanwhile, patients with pulmonary infiltration have distinct V-J gene usage and unique CDR3 signature, as well as BCR class switch recombination pattern. Finally, prior vaccination triggered less BCR IGHM/IGHD somatic hypermutation response, preserved the diversity of the entire adaptive immune repertoire, and provided clinical protection against severe or critical conditions following Omicron infection.DiscussionWe report a unique, comprehensive adaptive immune system signature in patients with pulmonary infiltration, which may serve as potential immunological biomarkers and therapeutic targets.

BackgroundT cells form one of the key pillars of adaptive immunity. Using their surface bound T cell antigen receptors (TCRs), these cells screen millions of antigens presented by major histocompatibility complex (MHC) or MHC-like molecules. In other protein families, the dynamics of protein-protein interactions have important implications for protein function. Case studies of TCR:class I peptide-MHCs (pMHC-Is) structures have reported mixed results on whether the binding interfaces undergo conformational change during engagement and no robust statistical quantification has been done to generalise these results. Thus, it remains an open question of whether movement occurs in the binding interface that enables the recognition and activation of T cells.MethodsIn this work, we quantify the conformational changes in the TCR:pMHC-I binding interface by creating a dataset of 391 structures, comprising 22 TCRs, 19 MHC alleles, and 79 peptide structures in both unbound (apo) and bound (holo) conformations.ResultsIn support of some case studies, we demonstrate that all complementarity determining region (CDR) loops move to a certain extent but only CDR3α and CDR3β loops modify their shape when binding pMHC-Is. We also map the contacts between TCRs and pMHC-Is, generating a novel fingerprint of TCRs on MHC molecules and show that the CDR3α tends to bind the N-terminus of the peptide and the CDR3β tends to bind the C-terminus of the peptide. Finally, we show that the presented peptides can undergo conformational changes when engaged by TCRs, as has been reported in past literature, but novelly show these changes depend on how the peptides are anchored in the MHC binding groove.ConclusionsOur work has implications in understanding the behaviour of TCR:pMHC-I interactions and providing insights that can be used for modelling Tcell antigen specificity, an ongoing grand challenge in immunology.

Isolation of tumor-specific T cells and their antigen receptors (TCRs) from malignant pleural effusions (MPE) may facilitate the development of TCR-transduced adoptive cellular immunotherapy products for advanced lung cancer patients. However, the characteristics and markers of tumor-specific T-cells in MPE are largely undefined. To this end, to establish the phenotypes and antigen specificities of CD8+ T cells, we performed single-cell RNA and TCR sequencing of samples from three advanced lung cancer patients. Dimensionality reduction on a total of 4,983 CD8+ T cells revealed 10 clusters including naïve, memory, and exhausted phenotypes. We focused particularly on exhausted T cell clusters and tested their TCR reactivity against neoantigens predicted from autologous cancer cell lines. Four different TCRs specific for the same neoantigen and one orphan TCR specific for the autologous cell line were identified from one of the patients. Differential gene expression analysis in tumor-specific T cells relative to the other T cells identified CXCL13, as a candidate gene expressed by tumor-specific T cells. In addition to expressing CXCL13, tumor-specific T cells were present in a higher proportion of T cells co-expressing PDCD1(PD-1)/TNFRSF9(4-1BB). Furthermore, flow cytometric analyses in advanced lung cancer patients with MPE documented that those with high PD-1/4-1BB expression have a better prognosis in the subset of 57 adenocarcinoma patients (p = .039). These data suggest that PD-1/4-1BB co-expression might identify tumor-specific CD8+ T cells in MPE, which are associated with patients’ prognosis. (233 words)

Adoptive T-cell therapies (ACTs) including tumor-infiltrating lymphocytes and engineered T cells (transgenic T-cell receptor and chimeric antigen receptor T cells), have made an important impact in the field of cancer treatment over the past years. Most of these therapies are typically administered systemically in approaches that facilitate the elimination of hematologic malignancies. Therapeutical efficacy against solid tumors, however, with the exception of tumor-infiltrating lymphocytes against melanoma, remains limited due to several barriers preventing lymphocyte access to the tumor bed. Building upon the experience of regional administration in other immunotherapies, the regional administration of adoptive cell therapies is being assessed to overcome this challenge, granting a first round of access of the transferred T cells to the tumor niche and thereby ensuring their activation and expansion. Intralesional and intracavitary routes of delivery have been tested with promising antitumor objective responses in preclinical and clinical studies. Additionally, several strategies are being developed to further improve T-cell activity after reinfusing them back to the patient such as combinations with other immunotherapy agents or direct engineering of the transferred T cells, achieving long-term immune memory. Clinical trials testing different regional adoptive T-cell therapies are ongoing but some issues related to methodology of administration and correct selection of the target antigen to avoid on-target/off-tumor side-effects need to be further evaluated and improved. Herein, we discuss the current preclinical and clinical landscape of intratumoral and locoregional delivery of adoptive T-cell therapies.

Abstract At the 3’ end of the C2 gene in the mammalian TRB locus, a distinct reverse TRBV30 gene (named TRBV31 in mice) has been conserved throughout evolution. In the fully annotated TRB locus of 14 mammals (including six orders), we observed noteworthy variations in the localization and quality of the reverse V30 genes and Recombination Signal Sequences (RSSs) in the gene trees of 13 mammals. Conversely, the forward V29 genes and RSSs were generally consistent with the species tree of their corresponding species. This finding suggested that the evolution of the reverse V30 gene was not synchronous and likely played a crucial role in regulating adaptive immune responses. To further investigate this possibility, we utilized single-cell TCR sequencing (scTCR-seq) and high-throughput sequencing (HTS) to analyze TCRβ CDR3 repertoires from both central and peripheral tissues of Primates (Homo sapiens and Macaca mulatta), Rodentia (Mus musculus: BALB/c, C57BL/6, and Kunming mice), Artiodactyla (Bos taurus and Bubalus bubalis), and Chiroptera (Rhinolophus affinis and Hipposideros armige). Our investigation revealed several novel observations: (1) The reverse V30 gene exhibits classical rearrangement patterns adhering to the ‘12/23 rule’ and the ‘D-J rearrangement preceding the V-(D-J) rearrangement’. This results in the formation of rearranged V30-D2J2, V30-D1J1, and V30-D1J2. However, we also identified ‘special rearrangement patterns’ wherein V30-D rearrangement preceding D-J rearrangement, giving rise to rearranged V30-D2-J1 and forward Vx-D2-J. (2) Compared to the ‘deletional rearrangement’ (looping out) of forward V1-V29 genes, the reverse V30 gene exhibits preferential utilization with ‘inversional rearrangement’. This may be attributed to the shorter distance between the V30 gene and D gene and the ‘inversional rearrangement’ modes. In summary, in the mammalian TRB locus, the reverse V30 gene has been uniquely preserved throughout evolution and preferentially utilized in V(D)J recombination, potentially serving a significant role in adaptive immunity. These results will pave the way for novel and specialized research into the mechanisms, efficiency, and function of V(D)J recombination in mammals.

Infection is inconceivable without T cells. T cells not only eliminate virus-infected cells and participate in the formation of immunological memory, but also indirectly modulate the humoral response through the selection and maintenance of specific B cells. The T-cell receptor (TCR) recognizes processed antigen presented on the surface of cells in the MHC of one of two classes. Thus, the formed TCR repertoire reflects the history of encountered antigens through the prism of the specific organism with a particular set of MHC. To investigate changes in the TCR repertoire in response to acute viral infection, we utilized a yellow fever vaccination model. The yellow fever vaccine has been a benchmark for both safety and efficacy for over half a century. The vaccine is based on a live attenuated virus, allowing the study of the immune response under conditions closely to the viral infection. The yellow fever-specific T-cell response to immunodominant peptides presented on HLA-A02 is well studied, but experiments with HLA-A02-negative donors are still lacking. The aim of this study was to examine the dynamics of changes in the T-cell repertoire structure that occur in response to yellow fever vaccination in a donor without the HLA-A02 allele. We found that the overall T-cell response dynamics were similar to that in HLA-A02-positive donors: vaccination led to rapid expansion of yellow fever-reactive clones by day 14. Despite the absence of a known immunodominant epitope for HLA I alleles in this donor, the immune response also shifted towards CD8⁺ T cells, with increasing of the CD8⁺ clones fraction by day 53. The amino acid sequences of CDR3 TCRb yellow fever specific clones formed a stable cluster by CD4⁺ T cells, further confirming the presence of novel immunogenic epitopes.

Abstract Background A vaccine against Trypanosoma cruzi, the agent of Chagas disease, would be an excellent additional tool for disease control. A recombinant vaccine based on Tc24 and TSA1 parasite antigens was found to be safe and immunogenic in naïve macaques. Methods We used RNA-sequencing and performed a transcriptomic analysis of PBMC responses to vaccination of naïve macaques after each vaccine dose, to shed light on the immunogenicity of this vaccine and guide the optimization of doses and formulation. We identified differentially expressed genes and pathways and characterized immunoglobulin and T cell receptor repertoires. Results RNA-sequencing analysis indicated a clear transcriptomic response of PBMCs after three vaccine doses, with the up-regulation of several immune cell activation pathways and a broad non-polarized immune profile. Analysis of the IgG repertoire showed that it had a rapid turnover with novel IgGs produced following each vaccine dose, while the TCR repertoire presented several persisting clones that were expanded after each vaccine dose. Conclusions These data suggest that three vaccine doses may be needed for optimum immunogenicity and support the further evaluation of the protective efficacy of this vaccine.

Abstract Purpose Immune checkpoint inhibitors (ICIs)-associated myocarditis was a rare yet severe complication observed in individuals undergoing immunotherapy. This study investigated the immune status and characteristics of patients diagnosed with ICIs- associated myocarditis. Methods A total of seven patients diagnosed with ICIs-associated myocarditis were included in the study, while five tumor patients without myocarditis were recruited as reference controls. Additionally, 30 healthy individuals were recruited as blank controls. Biochemical indices, electrocardiogram, and echocardiography measurements were obtained both prior to and following the occurrence of myocarditis. High-throughput sequencing of T cell receptor (TCR) was employed to assess the diversity and distribution characteristics of TCR CDR3 length, as well as the diversity of variable (V) and joining (J) genes of T lymphocytes in peripheral blood. Results In the seven patients with ICIs-associated myocarditis, Troponin T (TNT) levels exhibited a significant increase following myocarditis, while other parameters such as brain natriuretic peptide (BNP), QTc interval, and left ventricular ejection fraction (LVEF) did not show any significant differences. Through sequencing, it was observed that the diversity and uniformity of CDR3 in the ICIs-associated myocarditis patients were significantly diminished. Additionally, the distribution of CDR3 nucleotides deviated from normality, and variations in the utilization of V and J gene segments. Conclusion The reconstitution of the TCR immune repertoire may play a pivotal role in the recognition of antigens in patients with ICIs-associated myocarditis.

At the 3' end of the C2 gene in the mammalian TRB locus, a distinct reverse TRBV30 gene (named TRBV31 in mice) has been conserved throughout evolution. In the fully annotated TRB locus of 14 mammals (including six orders), we observed noteworthy variations in the localization and quality of the reverse V30 genes and Recombination Signal Sequences (RSSs) in the gene trees of 13 mammals. Conversely, the forward V29 genes and RSSs were generally consistent with the species tree of their corresponding species. This finding suggested that the evolution of the reverse V30 gene was not synchronous and likely played a crucial role in regulating adaptive immune responses. To further investigate this possibility, we utilized single-cell TCR sequencing (scTCR-seq) and high-throughput sequencing (HTS) to analyze TCRβ CDR3 repertoires from both central and peripheral tissues of Primates (Homo sapiens and Macaca mulatta), Rodentia (Mus musculus: BALB/c, C57BL/6, and Kunming mice), Artiodactyla (Bos taurus and Bubalus bubalis), and Chiroptera (Rhinolophus affinis and Hipposideros armige). Our investigation revealed several novel observations: (1) The reverse V30 gene exhibits classical rearrangement patterns adhering to the '12/23 rule' and the 'D-J rearrangement preceding the V-(D-J) rearrangement'. This results in the formation of rearranged V30-D2J2, V30-D1J1, and V30-D1J2. However, we also identified 'special rearrangement patterns' wherein V30-D rearrangement preceding D-J rearrangement, giving rise to rearranged V30-D2-J1 and forward Vx-D2-J. (2) Compared to the 'deletional rearrangement' (looping out) of forward V1-V29 genes, the reverse V30 gene exhibits preferential utilization with 'inversional rearrangement'. This may be attributed to the shorter distance between the V30 gene and D gene and the 'inversional rearrangement' modes. In summary, in the mammalian TRB locus, the reverse V30 gene has been uniquely preserved throughout evolution and preferentially utilized in V(D)J recombination, potentially serving a significant role in adaptive immunity. These results will pave the way for novel and specialized research into the mechanisms, efficiency, and function of V(D)J recombination in mammals. [ABSTRACT FROM AUTHOR]

Although ovarian cancer patients typically respond to standard of care therapies, including chemotherapy and DNA repair inhibitors, the majority of tumors recur highlighting the need for alternative therapies. Ovarian cancer is an immunogenic cancer in which the accumulation of tumor infiltrating lymphocytes (TILs), particularly T cells, is associated with better patient outcome. Thus, harnessing the immune system through passive administration of T cells, a process called adoptive cell therapy (ACT), is a promising therapeutic option for the treatment of ovarian cancer. There are multiple routes by which tumor-specific T cell products can be generated. Dendritic cell cancer vaccines can be administered to the patients to induce or bolster T cell responses against tumor antigens or be utilized ex vivo to prime T cells against tumor antigens; these T cells can then be prepared for infusion. ACT protocols can also utilize naturally-occurring tumor-reactive T cells isolated from a patient tumor, known as TILs, as these cells often are heterogeneous in composition and antigen specificity with patient-specific cancer recognition. Alternatively, T cells may be sourced from the peripheral blood, including those that are genetically modified to express a tumor antigen-specific T cell receptor (TCR) or chimeric antigen receptor (CAR) to redirect their specificity and promote their activity against tumor cells expressing the target tumor antigen. Here, we review current ACT strategies for ovarian cancer and provide insights into advancing ACT therapy strategies for the treatment of ovarian cancer. • Ovarian cancer is immunogenic and tumor infiltrating lymphocytes (TILs) are a prognostic biomarker for patient outcomes. • Adoptive cell therapies (ACTs) are promising therapeutic approaches for ovarian cancer. • Optimization of ACT strategies in ovarian cancer is needed for increased clinical efficacy and safety. [ABSTRACT FROM AUTHOR]

Latent human cytomegalovirus (hCMV) infection can pose a serious threat of reactivation and disease occurrence in immune‐compromised individuals. Although T cells are at the core of the protective immune response to hCMV infection, a detailed characterization of different T cell subsets involved in hCMV immunity is lacking. Here, in an unbiased manner, we characterized over 8000 hCMV‐reactive peripheral memory T cells isolated from seropositive human donors, at a single‐cell resolution by analysing their single‐cell transcriptomes paired with the T cell antigen receptor (TCR) repertoires. The hCMV‐reactive T cells were highly heterogeneous and consisted of different developmental and functional memory T cell subsets such as, long‐term memory precursors and effectors, T helper‐17, T regulatory cells (TREGs) and cytotoxic T lymphocytes (CTLs) of both CD4 and CD8 origin. The hCMV‐specific TREGs, in addition to being enriched for molecules known for their suppressive functions, showed enrichment for the interferon response signature gene sets. The hCMV‐specific CTLs were of two types, the pre‐effector‐ and effector‐like. The co‐clustering of hCMV‐specific CD4‐CTLs and CD8‐CTLs in both pre‐effector as well as effector clusters suggest shared transcriptomic signatures between them. The huge TCR clonal expansion of cytotoxic clusters suggests a dominant role in the protective immune response to CMV. The study uncovers the heterogeneity in the hCMV‐specific memory T cells revealing many functional subsets with potential implications in better understanding of hCMV‐specific T cell immunity. The data presented can serve as a knowledge base for designing vaccines and therapeutics. [ABSTRACT FROM AUTHOR]

Objectives: Recent immunologic study of the adaptive immune repertoire in the subglottic airway demonstrated high‐frequency T cell clones that do not overlap between individuals. However, the anatomic distribution and antigenic target of the T cell repertoire in the proximal airway mucosa remain unresolved. Methods: Single‐cell RNA sequencing of matched scar and unaffected mucosa from idiopathic subglottic stenosis patients (iSGS, n = 32) was performed and compared with airway mucosa from healthy controls (n = 10). T cell receptor (TCR) sequences were interrogated via similarity network analysis to explore antigenic targets using the published algorithm: Grouping of Lymphocyte Interactions by Paratope Hotspots (GLIPH2). Results: The mucosal T cell repertoire in healthy control airways consisted of highly expressed T cell clones conserved across anatomic subsites (trachea, bronchi, bronchioles, and lung). In iSGS, high‐frequency clones were equally represented in both scar and adjacent non‐scar tissue. Significant differences in repertoire structure between iSGS scar and unaffected mucosa was observed, driven by unique low‐frequency clones. GLIPH2 results suggest low‐frequency clones share targets between multiple iSGS patients. Conclusion: Healthy airway mucosa has a highly conserved T cell repertoire across multiple anatomic subsites. Similarly, iSGS patients have highly expressed T cell clones present in both scar and unaffected mucosa. iSGS airway scar possesses an abundance of less highly expanded clones with predicted antigen targets shared between patients. Interrogation of these shared motifs suggests abundant adaptive immunity to viral targets in iSGS airway scar. These results provide insight into disease pathogenesis and illuminate new treatment strategies in iSGS. Level of Evidence: NA Laryngoscope, 134:3245–3252, 2024 [ABSTRACT FROM AUTHOR]

Personalized cancer vaccines have emerged as a promising avenue for cancer treatment or prevention strategies. This approach targets the specific genetic alterations in individual patient's tumors, offering a more personalized and effective treatment option. Previous studies have shown that generalized peptide vaccines targeting a limited scope of gene mutations were ineffective, emphasizing the need for personalized approaches. While studies have explored personalized mRNA vaccines, personalized peptide vaccines have not yet been studied in this context. Pancreatic ductal adenocarcinoma (PDAC) remains challenging in oncology, necessitating innovative therapeutic strategies. In this study, we developed a personalized peptide vaccine design methodology, employing RNA sequencing (RNAseq) to identify prevalent gene mutations underlying PDAC development in a patient solid tumor tissue. We performed RNAseq analysis for trimming adapters, read alignment, and somatic variant calling. We also developed a Python program called SCGeneID, which validates the alignment of the RNAseq analysis. The Python program is freely available to download. Using chromosome number and locus data, SCGeneID identifies the target gene along the UCSC hg38 reference set. Based on the gene mutation data, we developed a personalized PDAC cancer vaccine that targeted 100 highly prevalent gene mutations in two patients. We predicted peptide-MHC binding affinity, immunogenicity, antigenicity, allergenicity, and toxicity for each epitope. Then, we selected the top 50 and 100 epitopes based on our previously published vaccine design methodology. Finally, we generated pMHC-TCR 3D molecular model complex structures, which are freely available to download. The designed personalized cancer vaccine contains epitopes commonly found in PDAC solid tumor tissue. Our personalized vaccine was composed of neoantigens, allowing for a more precise and targeted immune response against cancer cells. Additionally, we identified mutated genes, which were also found in the reference study, where we obtained the sequencing data, thus validating our vaccine design methodology. This is the first study designing a personalized peptide cancer vaccine targeting neoantigens using human patient data to identify gene mutations associated with the specific tumor of interest. [ABSTRACT FROM AUTHOR]

Chronic inflammation is pivotal in the pathogenesis of hepatocellular carcinoma (HCC). Histamine is a biologically active substance that amplifies the inflammatory and immune response and serves as a neurotransmitter. However, knowledge of histamine's role in HCC and its effects on immunotherapy remains lacking. We focused on histamine-related genes to investigate their potential role in HCC. The RNA-seq data and clinical information regarding HCC were obtained from The Cancer Genome Atlas (TCGA). After identifying the differentially expressed genes, we constructed a signature using the univariate Cox proportional hazard regression and least absolute shrinkage and selection operator (LASSO) analyses. The signature's predictive performance was evaluated using a receiver operating characteristic curve (ROC) analysis. Furthermore, drug sensitivity, immunotherapy effects, and enrichment analyses were conducted. Histamine-related gene expression in HCC was confirmed using quantitative real-time polymerase chain reaction (qRT-PCR). A histamine-related gene prognostic signature (HRGPS) was developed in TCGA. Time-dependent ROC and Kaplan–Meier survival analyses demonstrated the signature's strong predictive power. Importantly, patients in high-risk groups exhibited a higher frequency of TP53 mutations, elevated immune checkpoint-related gene expression, and increased infiltration of immunosuppressive cells—indicating a potentially favorable response to immunotherapy. In addition, drug sensitivity analysis revealed that the signature could effectively predict chemotherapy efficacy and sensitivity. qRT-PCR results validated histamine-related gene overexpression in HCC. Our findings demonstrate that inhibiting histamine-related genes and signaling pathways can impact the therapeutic effect of anti-PD-1/PD-L1. The precise predictive ability of our signature in determining the response to different therapeutic options highlights its potential clinical significance. [ABSTRACT FROM AUTHOR]

Autoimmune disease (AID) is a disease in which the body loses tolerance to autoantigens and the immune system attacks its own tissues, resulting in organ and tissue damage and certain clinical manifestations. Studies have proved that pathogenic T cells can be selectively inhibited or killed by TCR vaccine in the treatment of AID, thus bringing broad application prospect. This paper briefly summarizes the research status of TCR vaccine in AID field, regarding action mechanism, related diseases and safety of TCR vaccine. [ABSTRACT FROM AUTHOR]

This research work's central focus is synthesizing a novel hybrid compound, formulated as [C6H9N2]2Sb2Cl8. This compound was prepared using the slow evaporation method and confirmed through single-crystal X-ray diffraction at 293 K. It crystallizes in the triclinic system with the centrosymmetric space group P 1 ¯ symmetry, and its unit cell (Z = 2). The intermolecular interactions have been studied using Hirshfeld surface analysis and two-dimensional fingerprint plots, revealing that the Cl–H contacts contribute the most to the surface area (63.6%). Computational studies that include geometry optimization and harmonic vibrational frequencies were performed using B3LYP method with GENECP set. Acceptable consistency was observed between calculated and experimental results. The assignment of wavenumbers was based on potential energy distribution (PED) using Vibrational Energy Distribution Analysis (VEDA) software. The optical band gap determined by UV–Visible spectroscopy is 3.48 eV for a direct allowed transition. Impedance spectroscopy was performed over a temperature range of 313 K to 413 K and a frequency range of 0.1 Hz to 1 MHz. The Nyquist plots indicated the presence of grain contributions. The conductivity study revealed that the synthesized material exhibits semiconductor behavior. A thermally activated conduction process was identified through the study of alternating conductivity, with a calculated activation energy of 1.104 eV. Additionally, the title compound exhibits a negative temperature coefficient of resistivity (TCR) with value of − 13%, suggesting the suitability of the sample for IR radiation detection applications. [ABSTRACT FROM AUTHOR]

Background: A vaccine against Trypanosoma cruzi, the agent of Chagas disease, would be an excellent additional tool for disease control. A recombinant vaccine based on Tc24 and TSA1 parasite antigens was found to be safe and immunogenic in naïve macaques. Methods: We used RNA-sequencing and performed a transcriptomic analysis of PBMC responses to vaccination of naïve macaques after each vaccine dose, to shed light on the immunogenicity of this vaccine and guide the optimization of doses and formulation. We identified differentially expressed genes and pathways and characterized immunoglobulin and T cell receptor repertoires. Results: RNA-sequencing analysis indicated a clear transcriptomic response of PBMCs after three vaccine doses, with the up-regulation of several immune cell activation pathways and a broad non-polarized immune profile. Analysis of the IgG repertoire showed that it had a rapid turnover with novel IgGs produced following each vaccine dose, while the TCR repertoire presented several persisting clones that were expanded after each vaccine dose. Conclusions: These data suggest that three vaccine doses may be needed for optimum immunogenicity and support the further evaluation of the protective efficacy of this vaccine. [ABSTRACT FROM AUTHOR]

Myocarditis has emerged as a rare but lethal immune checkpoint inhibitor (ICI)‐associated toxicity. However, the exact mechanism and the specific therapeutic targets remain underexplored. In this study, we aim to characterise the transcriptomic profiles based on single‐cell RNA sequencing from ICI‐related myocarditis. Peripheral blood mononuclear cell (PBMC) samples were collected from four groups for single‐cell RNA sequencing: (1) patients with newly diagnosed lung squamous cell carcinoma before treatment (Control Group); (2) patients with lung squamous cell carcinoma with PD‐1 inhibitor therapy who did not develop myocarditis (PD‐1 Group); (3) patients during fulminant ICI‐related myocarditis onset (Myocarditis Group); and (4) Patients with fulminant ICI‐related myocarditis during disease remission (Recovery Group). Subcluster determination, functional analysis, single‐cell trajectory and cell–cell interaction analysis were performed after scRNA‐seq. Bulk‐RNA sequencing was performed for further validation. Our results revealed the diversity of cellular populations in ICI‐related myocarditis, marked by their distinct transcriptional profiles and biological functions. Monocytes, NKs as well as B cells contribute to the regulation of innate immunity and inflammation in ICI‐related myocarditis. With integrated analysis of scRNA‐seq and bulk sequencing, we identified S100A protein family as a potential serum marker for ICI‐related myocarditis. Our study has created a cell atlas of PBMC during ICI‐related myocarditis, which would shed light on the pathophysiological mechanism and potential therapeutic targets of ICI‐related myocarditis in continuous exploration. [ABSTRACT FROM AUTHOR]

The charge carrier's dynamics of La 0.7 (Sr 5/6 Na 1/6) 0.3 Mn 0.7 Ti 0.3 O 3 (LSNMTO) ceramic is conducted using the temperature and frequency dependences of the electrical conductivity and their scaling formalisms. The structural study indicates that LSNMTO crystallizes in a rhombohedral R 3 ‾ c perovskite structure with no detectible secondary phases. A phase transition from the high-temperature metallic behavior to the low-temperature semiconductor nature is observed from the electrical conductivity curve at T S-M = 415 K. Further, it is observed that the cation-anion-cation and the cation-cation interactions are present in the material, and play important role in governing the electrical behaviors of LSNMTO. From 200 K to 415 K, the Non-adiabatic Small Polaron Hopping is the predominant conduction process, although the Mott-Variable Range Hopping mechanism governs the conductivity at low temperatures. In the intermediate temperature range, the dynamic of the charge carriers is explained using the Shklovskii Efros model. The frequency-activated conductivity obeyed the universal laws (double-Jonscher and Jonscher laws). At high frequencies, the dispersion of the conductivity spectra is attributed to the presence of hopping and tunneling conduction processes. The Time-Temperature Superposition Principle (TTSP) is obeyed over a large temperature range from 160 K to 350 K. Below 160 K, the deviation from the TTSP is attributed to the coexistence of hopping and tunneling conduction mechanisms. Deviations from the Summerfield scaling and shifts of the isotherms to higher values on decreasing the temperature are due to the local structural disorder in LSNMTO. Therefore, the structural particularities of LSNMTO can result in diverse conduction pathways giving an increase to the deviations from the Summerfield scaling. The studied ceramic exhibits a very motivating maximum negative temperature coefficient of resistance NTCR = −13.36% which is significantly elevated as compared to previously investigated compounds. [ABSTRACT FROM AUTHOR]

Objective: Using single cell sequencing to analyze the characteristics of the immune repertoire of SARS-CoV-2 patients at different infection stages, and to explore the possible pathogenesis. Methods: Obtaining data in the NCBI database, and healthy control, progression and convalescence groups were set up. Analysis of single cell sequencing data by RStudio, Origin, Hipliot and Excel software. Results: TCR plays an important role in antigen recognition and virus clearance. Characteristics of the three immune repertoires are very different. The number of clones exceeded 26.92%. The length distribution of α chain CDR3 was concentrated on 14 amino acids, while β-chain was concentrated on 15 amino acids. The frequency of gene fragments in V and J regions were different, and the frequency of TRAV13-1, TRAJ20, TRBV20-1 and TRBJ2-1 were statistically significant (P<0.05). Further V-J gene combination analysis showed that there were significant differences in the frequency of single chain V-J between the control group and the progression group, the control group and the rehabilitation group (P<0.05). The highest frequency of αβ double chain V-J in the control group was TRAV19-J34-TRBV4-1-J2-1, the highest frequency of αβ double-stranded V-J in the progression group was TRAV12-1-J30-TRBV19-1-J2-1, and the highest frequency of αβ double chain V-J in the convalescence group was TRAV12-2-J52-TRBV7-9-J1-5. Conclusion: This study analyzes the global characteristics of T cells in the immune repertoire, which is helpful to understand the pathogenesis of SARS-CoV-2 patients, timely and effective treatment of patients in the early stages of infection. [ABSTRACT FROM AUTHOR]

IntroductionAdoptive cell therapy using TCR-engineered T-cells is one of the most effective strategies against tumor cells. The TCR T-cell approach has been well tested against a variety of blood neoplasms but is yet to be deeply tested against solid tumors. Among solid tumors, cancer-testis antigens are the most prominent targets for tumor-specific therapy, as they are usually found on cells that lie behind blood-tissue barriers.MethodsWe have employed a novel efficient protocol for MAGE-A3-specific T-cell clonal expansion, performed single-cell multi-omic analysis of the expanded T-cells via BD Rhapsody, engineered a selected T-cell receptor into a lentiviral construct, and tested it in an in vitro LDH-cytotoxicity test.Results and discussionWe have observed a 191-fold increase in the MAGE-A3-specific T-cell abundance, obtained a dominant T-cell receptor via single-cell multi-omic BD Rhapsody data analysis in the TCRscape bioinformatics tool, and observed potent cytotoxicity of the dominant-clonotype transduced TCR T-cells against a MAGE-A3-positive tumor. We have demonstrated the efficiency of our T-cell enrichment protocol in obtaining potent anti-tumor T-cells and their T-cell receptors, especially when paired with the modern single-cell analysis methods.

Immunotherapy represents a promising strategy for cancer treatment that utilizes immune cells or drugs to activate the patient’s own immune system and eliminate cancer cells. One of the most exciting advances within this field is the targeting of neoantigens, which are peptides derived from non-synonymous somatic mutations that are found exclusively within cancer cells and absent in normal cells. Although neoantigen-based therapeutic vaccines have not received approval for standard cancer treatment, early clinical trials have yielded encouraging outcomes as standalone monotherapy or when combined with checkpoint inhibitors. Progress made in high-throughput sequencing and bioinformatics have greatly facilitated the precise and efficient identification of neoantigens. Consequently, personalized neoantigen-based vaccines tailored to each patient have been developed that are capable of eliciting a robust and long-lasting immune response which effectively eliminates tumors and prevents recurrences. This review provides a concise overview consolidating the latest clinical advances in neoantigen-based therapeutic vaccines, and also discusses challenges and future perspectives for this innovative approach, particularly emphasizing the potential of neoantigen-based therapeutic vaccines to enhance clinical efficacy against advanced solid tumors.

Adoptive cell therapies involve infusing engineered immune cells into cancer patients to recognize and eliminate tumor cells. Adoptive cell therapy, as a form of living drug, has undergone explosive growth over the past decade. The recognition of tumor antigens by the T-cell receptor (TCR) is one of the natural mechanisms that the immune system used to eliminate tumor cells. TCR-T cell therapy, which involves introducing exogenous TCRs into patients’ T cells, is a novel cell therapy strategy. TCR-T cell therapy can target the entire proteome of cancer cells. Engineering T cells with exogenous TCRs to help patients combat cancer has achieved success in clinical trials, particularly in treating solid tumors. In this review, we examine the progress of TCR-T cell therapy over the past five years. This includes the discovery of new tumor antigens, protein engineering techniques for TCR, reprogramming strategies for TCR-T cell therapy, clinical studies on TCR-T cell therapy, and the advancement of TCR-T cell therapy in China. We also propose several potential directions for the future development of TCR-T cell therapy.

Abstract Background Small intestinal monomorphic–epitheliotropic intestinal T-cell lymphoma (MEITL) is a rare aggressive T-cell lymphoma originating in the gastrointestinal tract. This study aimed to investigate the clinicopathological features, immunophenotypes, and molecular genetic changes of MEITL. Methods The clinicopathological data for three patients with surgically resected MEITL of the small intestine were collected. Next, immunohistochemical labeling, Epstein–Barr virus (EBV) in situ hybridization, assessment of clonal rearrangement of T-cell receptor (TCR) genes, and next-generation sequencing (NGS) were performed. Results Of the three patients, two were male and one was female, with ages of 61, 67, and 73 years, respectively. Clinical manifestations were predominantly abdominal pain and distension. Histopathology revealed infiltrative growth of small-to-medium-sized lymphocytes with a consistent morphology between the intestinal walls, accompanied by an obvious pro-epithelial phenomenon. The expression of CD3, CD8, CD43, CD56, TIA-1, CD103, H3K36me3, and Bcl-2 was detected, and the Ki-67 proliferation index ranged from 50% to 80%. All three patients tested negative for EBER. However, monoclonal rearrangement of the TCR gene was detected in them. NGS testing showed a JAK3 mutation in all three cases. Further, STAT5B, SETD2, and TP53 mutations were each observed in two cases, and a BCOR mutation was found in one case. All patients were treated with chemotherapy after surgery. Two patients died 7 and 15 month post-operation, and one patient survived for 5 months of follow-up. Conclusions Our findings demonstrate that mutations in JAK3 and STAT5B of the JAK/STAT pathway and inactivation of the oncogene SETD2 markedly contribute to the lymphomagenesis of MEITL.