Immune monitoring in pediatric kidney transplant.

BACKGROUND: Long-term outcomes in pediatric kidney transplantation remain suboptimal, largely related to chronic rejection. Creatinine is a late marker of renal injury, and more sensitive, early markers of allograft injury are an active area of current research. METHODS: This is an educational review summarizing existing strategies for monitoring for rejection in kidney transplant recipients. RESULTS: We summarize supporting currently available clinical tests, including surveillance biopsy, donor specific antibodies, and donor-derived cell free DNA, as well as the potential limitations of these studies. In addition, we review the current avenues of active research, including transcriptomics, proteomics, metabolomics, and torque tenovirus levels. CONCLUSION: Advancing the use of noninvasive immune monitoring will depend on well-designed multicenter trials that include patients with stable graft function, include biopsy results on all patients, and can demonstrate both association with a patient-relevant clinical endpoint such as graft survival or change in glomerular filtration rate and a potential timepoint for intervention.

[Optimizing efficacy and security of CAR-T cells, and immune monitoring]. / Optimisation de l'efficacité et de la sécurité d'utilisation des lymphocytes CAR-T.

The immune system plays a critical role in the control and eradication of tumors. A better understanding of the anti-tumor immune mechanisms over the last decade has led to the development of immunotherapies, including cellular therapies such as those using CAR-T cells. These therapies have been remarkably effective in hematological malignancies. However, their application to solid tumors requires some optimization. Many efforts are being made in this regard, both to increase the efficacy of CAR-T cells, and to make them more secure. For the former goal, there is a need for the identification of new targets, better activation strategies, or arming T cells in a way that makes them able to overcome intra-tumoral barriers. For the latter goal, dose adjustment, locoregional administration or use of suicide genes are currently investigated as ways to mitigate the risks of this therapy. Together, these adjustments will permit larger applicability of CAR-T cells, in anti-tumor immunity, but also in the context of auto-immune diseases or fibrolytic therapies.

Title: Optimisation de l'efficacité et de la sécurité d'utilisation des lymphocytes CAR-T. Abstract: Le système immunitaire joue un rôle déterminant dans le contrôle et l'éradication des tumeurs. Une meilleure compréhension des mécanismes en jeu a permis le développement des immunothérapies, et notamment des thérapies par lymphocytes CAR-T. Ces thérapies ont montré une grande efficacité dans les maladies hématologiques, mais leur application aux tumeurs solides nécessite des optimisations pour améliorer leur efficacité et leur sécurité. Ces ajustements permettront une plus grande applicabilité des lymphocytes CAR-T, non seulement pour les traitements anti-tumoraux mais aussi pour le traitement de maladies auto-immunes ou fibreuses.

Predictability of B cell clonal persistence and immunosurveillance in breast cancer.

B cells and T cells are important components of the adaptive immune system and mediate anticancer immunity. The T cell landscape in cancer is well characterized, but the contribution of B cells to anticancer immunosurveillance is less well explored. Here we show an integrative analysis of the B cell and T cell receptor repertoire from individuals with metastatic breast cancer and individuals with early breast cancer during neoadjuvant therapy. Using immune receptor, RNA and whole-exome sequencing, we show that both B cell and T cell responses seem to coevolve with the metastatic cancer genomes and mirror tumor mutational and neoantigen architecture. B cell clones associated with metastatic immunosurveillance and temporal persistence were more expanded and distinct from site-specific clones. B cell clonal immunosurveillance and temporal persistence are predictable from the clonal structure, with higher-centrality B cell antigen receptors more likely to be detected across multiple metastases or across time. This predictability was generalizable across other immune-mediated disorders. This work lays a foundation for prioritizing antibody sequences for therapeutic targeting in cancer.

Advanced in immunological monitoring of HIV infection: profile of immune cells and cytokines in people living with HIV-1 in Benin.

BACKGROUND: Immune cells and cytokines have been linked to viremia dynamic and immune status during HIV infection. They may serve as useful biomarkers in the monitoring of people living with HIV-1 (PLHIV-1). The present work was aimed to assess whether cytokines and immune cell profiles may help in the therapeutic follow-up of PLHIV-1. METHODS: Forty PLHIV-1 in treatment success (PLHIV-1s) and fifty PLHIV-1 in treatment failure (PLHIV-1f) followed at the University Hospital of Abomey-Calavi/Sô-Ava in Benin were enrolled. Twenty healthy persons were also recruited as control group. Circulating cytokines and immune cells were quantified respectively by ELISA and flow cytometry. RESULTS: PLHIV-1 exhibited low proportions of CD4 + T cells, NK, NKT, granulocytes, classical and non-classical monocytes, and high proportions of CD8 + T cells, particularly in the PLHIV-1f group, compared to control subjects. Eosinophils, neutrophils and B cell frequencies did not change between the study groups. Circulating IFN-γ decreased whereas IL-4 significantly increased in PLHIV-1s compared to PLHIV-1f and control subjects even though the HIV infection in PLHIV-1s downregulated the high Th1 phenotype observed in control subjects. However, Th1/Th2 ratio remained biased to a Th1 phenotype in PLHIV-1f, suggesting that high viral load may have maintained a potential pro-inflammatory status in these patients. Data on inflammatory cytokines showed that IL-6 and TNF-α concentrations were significantly higher in PLHIV-1s and PLHIV-1f groups than in control subjects. Significant high levels of IL-5 and IL-7 were observed in PLHIV-1f compared to controls whereas PLHIV-1s presented only a high level of IL-5. No change was observed in IL-13 levels between the study groups. CONCLUSION: Our study shows that, in addition to CD4/CD8 T cell ratio, NK and NKT cells along with IL-6, TNF-α, IL-5 and IL-7 cytokines could serve as valuable immunological biomarkers in the therapeutic monitoring of PLHIV-1 although a larger number of patients would be necessary to confirm these results.

Obesity-related T cell dysfunction impairs immunosurveillance and increases cancer risk.

Obesity is a well-established risk factor for human cancer, yet the underlying mechanisms remain elusive. Immune dysfunction is commonly associated with obesity but whether compromised immune surveillance contributes to cancer susceptibility in individuals with obesity is unclear. Here we use a mouse model of diet-induced obesity to investigate tumor-infiltrating CD8 + T cell responses in lean, obese, and previously obese hosts that lost weight through either dietary restriction or treatment with semaglutide. While both strategies reduce body mass, only dietary intervention restores T cell function and improves responses to immunotherapy. In mice exposed to a chemical carcinogen, obesity-related immune dysfunction leads to higher incidence of sarcoma development. However, impaired immunoediting in the obese environment enhances tumor immunogenicity, making the malignancies highly sensitive to immunotherapy. These findings offer insight into the complex interplay between obesity, immunity and cancer, and provide explanation for the obesity paradox observed in clinical immunotherapy settings.

Urolithin-A Promotes CD8+ T Cell-mediated Cancer Immunosurveillance via FOXO1 Activation.

Naïve T cells are key players in cancer immunosurveillance, even though their function declines during tumor progression. Thus, interventions capable of sustaining the quality and function of naïve T cells are needed to improve cancer immunoprevention.In this context, we studied the capacity of Urolithin-A (UroA), a potent mitophagy inducer, to enhance T cell-mediated cancer immunosurveillance.We discovered that UroA improved the cancer immune response by activating the transcription factor FOXO1 in CD8+ T cell. Sustained FOXO1 activation promoted the expression of the adhesion molecule L-selectin (CD62L) resulting in the expansion of the naïve T cells population. We found that UroA reduces FOXO1 phosphorylation favoring its nuclear localization and transcriptional activity. Overall, our findings determine FOXO1 as a novel molecular target of UroA in CD8+ T cells and indicate UroA as promising immunomodulator to improve cancer immunosurveillance. SIGNIFICANCE: Urolithin-A, a potent mitophagy inducer, emerges as a promising tool to enhance cancer immunosurveillance by activating the FOXO1 transcription factor in CD8+ T cells. This activation promotes the expansion of naïve T cells, offering a novel avenue for improving cancer immune response and highlighting UroA as a potential immunomodulator for bolstering our body's defenses against cancer.

HIF-1α/m6A/NF-κB/CCL3 axis-mediated immunosurveillance participates in low level benzene-related erythrohematopoietic development toxicity.

Defective erythropoiesis is one of the causes of anemia and leukemia. However, the mechanisms underlying defective erythropoiesis under a low-dose environment of benzene are poorly understood. In the present study, multiple omics (transcriptomics and metabolomics) and methods from epidemiology to experimental biology (e.g., benzene-induced (WT and HIF-1α + ) mouse, hiPSC-derived HSPCs) were used. Here, we showed that erythropoiesis is more easily impacted than other blood cells, and the process is reversible, which involves HIF-1 and NF-kB signaling pathways in low-level benzene exposure workers. Decreased HIF-1α expression in benzene-induced mouse bone marrow resulted in DNA damage, senescence, and apoptosis in BMCs and HSCs, causing disturbances in iron homeostasis and erythropoiesis. We further revealed that HIF-1α mediates CCL3/macrophage-related immunosurveillance against benzene-induced senescent and damaged cells and contributes to iron homeostasis. Mechanistically, we showed that m6A modification is essential in this process. Benzene-induced depletion of m6A promotes the mRNA stability of gene NFKBIA and regulates the NF-κB/CCL3 pathway, which is regulated by HIF-1α/METTL3/YTHDF2. Overall, our results identified an unidentified role for HIF-1α, m6A, and the NF-kB signaling machinery in erythroid progenitor cells, suggesting that HIF-1α/METTL3/YTHDF2-m6A/NF-κB/CCL3 axis may be a potential prevention and therapeutic target for chronic exposure of humans to benzene-associated anemia and leukemia.

Cell-mediated barriers in cancer immunosurveillance.

The immune cells within the tumor microenvironment (TME) exert multifaceted functions ranging from tumor-antagonizing or tumor-promoting activities. During the initial phases of tumor development, the tumor-antagonizing immune cells in the TME combat cancer cells in an immune surveillance process. However, with time, cancer cells can evade detection and impede the immune cells' effectiveness through diverse mechanisms, such as decreasing immunogenic antigen presentation on their surfaces and/or secreting anti-immune factors that cause tolerance in TME. Moreover, some immune cells cause immunosuppressive situations and inhibit antitumoral immune responses. Physical and cellular-mediated barriers in the TME, such as cancer-associated fibroblasts, tumor endothelium, the altered lipid composition of tumor cells, and exosomes secreted from cancer cells, also mediate immunosuppression and prevent extravasation of immune cells. Due to successful clinical outcomes of cancer treatment strategies the potential barriers must be identified and addressed. We need to figure out how to optimize cancer immunotherapy strategies, and how to combine therapeutic approaches for maximum clinical benefit. This review provides a detailed overview of various cells and molecules in the TME, their association with escaping from immune surveillance, therapeutic targets, and future perspectives for improving cancer immunotherapy.

SHP-1 inhibition targets leukaemia stem cells to restore immunosurveillance and enhance chemosensitivity by metabolic reprogramming.

Leukaemia stem cells (LSCs) in acute myeloid leukaemia present a considerable treatment challenge due to their resistance to chemotherapy and immunosurveillance. The connection between these properties in LSCs remains poorly understood. Here we demonstrate that inhibition of tyrosine phosphatase SHP-1 in LSCs increases their glycolysis and oxidative phosphorylation, enhancing their sensitivity to chemotherapy and vulnerability to immunosurveillance. Mechanistically, SHP-1 inhibition leads to the upregulation of phosphofructokinase platelet (PFKP) through the AKT-ß-catenin pathway. The increase in PFKP elevates energy metabolic activities and, as a consequence, enhances the sensitivity of LSCs to chemotherapeutic agents. Moreover, the upregulation of PFKP promotes MYC degradation and, consequently, reduces the immune evasion abilities of LSCs. Overall, our study demonstrates that targeting SHP-1 disrupts the metabolic balance in LSCs, thereby increasing their vulnerability to chemotherapy and immunosurveillance. This approach offers a promising strategy to overcome LSC resistance in acute myeloid leukaemia.

Evidence and therapeutic implications of biomechanically regulated immunosurveillance in cancer and other diseases.

Disease progression is usually accompanied by changes in the biochemical composition of cells and tissues and their biophysical properties. For instance, hallmarks of cancer include the stiffening of tissues caused by extracellular matrix remodelling and the softening of individual cancer cells. In this context, accumulating evidence has shown that immune cells sense and respond to mechanical signals from the environment. However, the mechanisms regulating these mechanical aspects of immune surveillance remain partially understood. The growing appreciation for the 'mechano-immunology' field has urged researchers to investigate how immune cells sense and respond to mechanical cues in various disease settings, paving the way for the development of novel engineering strategies that aim at mechanically modulating and potentiating immune cells for enhanced immunotherapies. Recent pioneer developments in this direction have laid the foundations for leveraging 'mechanical immunoengineering' strategies to treat various diseases. This Review first outlines the mechanical changes occurring during pathological progression in several diseases, including cancer, fibrosis and infection. We next highlight the mechanosensitive nature of immune cells and how mechanical forces govern the immune responses in different diseases. Finally, we discuss how targeting the biomechanical features of the disease milieu and immune cells is a promising strategy for manipulating therapeutic outcomes.

Immunosurveillance encounters cancer metabolism.

Tumor cells reprogram nutrient acquisition and metabolic pathways to meet their energetic, biosynthetic, and redox demands. Similarly, metabolic processes in immune cells support host immunity against cancer and determine differentiation and fate of leukocytes. Thus, metabolic deregulation and imbalance in immune cells within the tumor microenvironment have been reported to drive immune evasion and to compromise therapeutic outcomes. Interestingly, emerging evidence indicates that anti-tumor immunity could modulate tumor heterogeneity, aggressiveness, and metabolic reprogramming, suggesting that immunosurveillance can instruct cancer progression in multiple dimensions. This review summarizes our current understanding of how metabolic crosstalk within tumors affects immunogenicity of tumor cells and promotes cancer progression. Furthermore, we explain how defects in the metabolic cascade can contribute to developing dysfunctional immune responses against cancers and discuss the contribution of immunosurveillance to these defects as a feedback mechanism. Finally, we highlight ongoing clinical trials and new therapeutic strategies targeting cellular metabolism in cancer.

Immunosurveillance associated with upper respiratory symptoms in elite swimmers: The 8-month period leading into Commonwealth Games.

OBJECTIVES: To monitor individual mucosal immunity and identify potential risk factors of upper respiratory symptoms in elite swimmers over a competitive season. DESIGN: Eight-month longitudinal study, observing mucosal immunity, Epstein-Barr virus status, training loads and illness symptoms of elite international swimmers, leading into the Commonwealth Games 2018. METHODS: Participants were fourteen elite swimmers (age ±â€¯standard deviation = 19.9 ±â€¯0.8 years, height = 178.9 ±â€¯6.3 cm, and mass = 75.0 ±â€¯7.7 kg). Self-reported upper respiratory symptoms, training load and saliva samples were collected weekly. Venous blood samples were taken at study commencement to determine Epstein-Barr virus status. RESULTS: Throughout the study, 70 episodes of upper respiratory symptoms were recorded resulting in 34 days of missed training. Incidence (p = 0.001), severity (p = 0.022), and duration of upper respiratory symptoms (p = 0.001) were significantly higher during high training loads, compared to low. Eight swimmers (61 %) had evidence of past infection with Epstein-Barr virus, but this had no relationship with incidence, severity, or duration of upper respiratory symptoms (p > 0.05). Relative individual salivary immunoglobulin A concentration was 12 % lower when upper respiratory symptoms were present but was not statistically significant (p = 0.101). CONCLUSIONS: This study highlights the importance of individual athlete monitoring, to identify swimmers at increased illness risk. Identification of possible risk factors for upper respiratory symptoms, such as increased training load, may allow for modifications in training or other illness preventative strategies for elite swimmers.

Immunosurveillance in clinical cancer management.

The progression of cancer involves a critical step in which malignant cells escape from control by the immune system. Antineoplastic agents are particularly efficient when they succeed in restoring such control (immunosurveillance) or at least establish an equilibrium state that slows down disease progression. This is true not only for immunotherapies, such as immune checkpoint inhibitors (ICIs), but also for conventional chemotherapy, targeted anticancer agents, and radiation therapy. Thus, therapeutics that stress and kill cancer cells while provoking a tumor-targeting immune response, referred to as immunogenic cell death, are particularly useful in combination with ICIs. Modern oncology regimens are increasingly using such combinations, which are referred to as chemoimmunotherapy, as well as combinations of multiple ICIs. However, the latter are generally associated with severe side effects compared with single-agent ICIs. Of note, the success of these combinatorial strategies against locally advanced or metastatic cancers is now spurring successful attempts to move them past the postoperative (adjuvant) setting to the preoperative (neoadjuvant) setting, even for patients with operable cancers. Here, the authors critically discuss the importance of immunosurveillance in modern clinical cancer management.

Ibrutinib-based therapy reinvigorates CD8+ T cells compared to chemoimmunotherapy: immune monitoring from the E1912 trial.

ABSTRACT: Bruton tyrosine kinase inhibitors (BTKis) that target B-cell receptor signaling have led to a paradigm shift in chronic lymphocytic leukemia (CLL) treatment. BTKis have been shown to reduce abnormally high CLL-associated T-cell counts and the expression of immune checkpoint receptors concomitantly with tumor reduction. However, the impact of BTKi therapy on T-cell function has not been fully characterized. Here, we performed longitudinal immunophenotypic and functional analysis of pretreatment and on-treatment (6 and 12 months) peripheral blood samples from patients in the phase 3 E1912 trial comparing ibrutinib-rituximab with fludarabine, cyclophosphamide, and rituximab (FCR). Intriguingly, we report that despite reduced overall T-cell counts; higher numbers of T cells, including effector CD8+ subsets at baseline and at the 6-month time point, associated with no infections; and favorable progression-free survival in the ibrutinib-rituximab arm. Assays demonstrated enhanced anti-CLL T-cell killing function during ibrutinib-rituximab treatment, including a switch from predominantly CD4+ T-cell:CLL immune synapses at baseline to increased CD8+ lytic synapses on-therapy. Conversely, in the FCR arm, higher T-cell numbers correlated with adverse clinical responses and showed no functional improvement. We further demonstrate the potential of exploiting rejuvenated T-cell cytotoxicity during ibrutinib-rituximab treatment, using the bispecific antibody glofitamab, supporting combination immunotherapy approaches.

Cell fusion upregulates PD-L1 expression for evasion from immunosurveillance.

MSCs (mesenchymal stem cells), responsible for tissue repair, rarely undergo cell fusion with somatic cells. Here, we show that ~5% of bladder cancer cells (UMUC-3) fuses with bone marrow-derived MSC (BM-MSC) in co-culture and maintains high tumorigenicity. In eleven fusion cell clones that have been established, Mb-scale deletions carried by the bladder cancer cells are mostly absent in the fusion cells, but copy number gains contributed by the cancer cells have stayed. Fusion cells exhibit increased populations of mitotic cells with 3-polar spindles, indicative of genomic instability. They grow faster in vitro and exhibit higher colony formation in anchorage-independent growth assay in soft agar than the parent UMUC-3 does. Fusion cells develop tumors, after 4 weeks of time lag, as efficiently as the parent UMUC-3 does in xenograft experiments. 264 genes are identified whose expression is specifically altered in the fusion cells. Many of them are interferon-stimulated genes (ISG), but are activated in a manner independent of interferon. Among them, we show that PD-L1 is induced in fusion cells, and its knockout decreases tumorigenesis in a xenograft model. PD-L1 is induced in a manner independent of STAT1 known to regulate PD-L1 expression, but is regulated by histone modification, and is likely to inhibit phagocytosis by PD1-expressing macrophages, thus protecting cancer cells from immunological attacks. The fusion cells overexpress multiple cytokines including CCL2 that cause tumor progression by converting infiltrating macrophages to tumor-associated-macrophage (TAM). The results present mechanisms of how cell fusion promotes tumorigenesis, revealing a novel link between cell fusion and PD-L1, and underscore the efficacy of cancer immunotherapy.

Elucidating Immune Monitoring of Tissue-Resident Macrophages by Intravital Microscopy.

Intravital microscopy is an invaluable tool to study in real time the dynamic behavior of leukocytes in vivo. We describe herein a simple protocol for time-lapse imaging of tissue-resident macrophages in intact kidney, liver, and spleen in live mice. This method can be used in any commercially available inverted confocal microscope, doesn't require expensive lasers or optics, exhibits minimal organ perturbation, photo bleaching, or phototoxicity, and, hence, it enables the study of tissue-resident macrophages in situ and in vivo under steady state and inflammation.

Calligraphy of Nanoplasmonic Bioink-Based Multiplex Immunosensor for Precision Immune Monitoring and Modulation.

Immunomodulation therapies have attracted immense interest recently for the treatment of immune-related diseases, such as cancer and viral infections. This new wave of enthusiasm for immunomodulators, predominantly revolving around cytokines, has spurred emerging needs and opportunities for novel immune monitoring and diagnostic tools. Considering the highly dynamic immune status and limited window for therapeutic intervention, precise real-time detection of cytokines is critical to effectively monitor and manage the immune system and optimize the therapeutic outcome. The clinical success of such a rapid, sensitive, multiplex immunoanalytical platform further requires the system to have ease of integration and fabrication for sample sparing and large-scale production toward massive parallel analysis. In this article, we developed a nanoplasmonic bioink-based, label-free, multiplex immunosensor that can be readily "written" onto a glass substrate via one-step calligraphy patterning. This facile nanolithography technique allows programmable patterning of a minimum of 3 µL of nanoplasmonic bioink in 1 min and thus enables fabrication of a nanoplasmonic microarray immunosensor with 2 h simple incubation. The developed immunosensor was successfully applied for real-time, parallel detection of multiple cytokines (e.g., interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and transforming growth factor-beta (TGF-ß)) in immunomodulated macrophage samples. This integrated platform synergistically incorporates the concepts of nanosynthesis, nanofabrication, and nanobiosensing, showing great potential in the scalable production of label-free multiplex immunosensing devices with superior analytical performance for clinical applications in immunodiagnostics and immunotherapy.