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Scientific Reports Jul 2024Targeting intracellular inhibiting proteins has been revealed to be a promising strategy to improve CD8 T cell anti-tumor efficacy. Here, we are focusing on...
Targeting intracellular inhibiting proteins has been revealed to be a promising strategy to improve CD8 T cell anti-tumor efficacy. Here, we are focusing on intracellular inhibiting proteins specific to TCR signaling: DOK1 and DOK2 expressed in T cells. We hypothesized that depletion of intracellular inhibition checkpoint DOK1 and DOK2 could improve CD8 T-cell based cancer therapies. To evaluate the role of DOK1 and DOK2 depletion in physiology and effector function of CD8 T lymphocytes and in cancer progression, we established a transgenic T cell receptor mouse model specific to melanoma antigen hgp100 (pmel-1 TCR Tg) in WT and Dok1/Dok2 DKO (double KO) mice. We showed that both DOK1 and DOK2 depletion in CD8 T cells after an in vitro pre-stimulation induced a higher percentage of effector memory T cells as well as an up regulation of TCR signaling cascade- induced by CD3 mAbs, including the increased levels of pAKT and pERK, two major phosphoproteins involved in T cell functions. Interestingly, this improved TCR signaling was not observed in naïve CD8 T cells. Despite this enhanced TCR signaling essentially shown upon stimulation via CD3 mAbs, pre-stimulated Dok1/Dok2 DKO CD8 T cells did not show any increase in their activation or cytotoxic capacities against melanoma cell line expressing hgp100 in vitro. Altogether we demonstrate here a novel aspect of the negative regulation by DOK1 and DOK2 proteins in CD8 T cells. Indeed, our results allow us to conclude that DOK1 and DOK2 have an inhibitory role following long term T cell stimulations.
Topics: Animals; CD8-Positive T-Lymphocytes; RNA-Binding Proteins; Signal Transduction; Mice; Adaptor Proteins, Signal Transducing; Phosphoproteins; DNA-Binding Proteins; Immunologic Memory; Receptors, Antigen, T-Cell; Mice, Knockout; Cell Line, Tumor; Mice, Transgenic
PubMed: 38956389
DOI: 10.1038/s41598-024-66075-0 -
Scientific Reports Jul 2024The systemic immune-inflammation index (SII), a metric reflecting systemic inflammatory response and immune activation, remains underexplored concerning its correlation...
The systemic immune-inflammation index (SII), a metric reflecting systemic inflammatory response and immune activation, remains underexplored concerning its correlation with mortality among rheumatoid arthritis (RA) patients. This study aimed to delineate the association between SII and both all-cause and cardiovascular mortality within the cohort of American adults diagnosed with RA, utilizing data from the National Health and Nutrition Examination Survey (NHANES) spanning 1999 to 2018. The investigation extracted data from NHANES cycles between 1999 and 2018, identifying RA patients through questionnaire responses. The SII was computed based on complete blood counts, employing the formula: (platelets × neutrophils) / lymphocytes. The optimal SII cutoff value for significant survival outcomes was determined using maximally selected rank statistics. Multivariable Cox proportional hazards models assessed the relationship between SII levels and mortality (all-cause and cardiovascular) among RA patients, with subgroup analyses examining potential modifications by clinical confounders. Additionally, restricted cubic spline (RCS) analyses were conducted to explore the linearity of the SII-mortality association. The study encompassed 2070 American adults with RA, among whom 287 exhibited a higher SII (≥ 919.75) and 1783 a lower SII (< 919.75). Over a median follow-up duration of 108 months, 602 participants died. After adjustments for demographic, socioeconomic, and lifestyle variables, a higher SII was associated with a 1.48-fold increased risk of all-cause mortality (hazard ratio [HR] = 1.48, 95% confidence interval [CI] 1.21-1.81, P < 0.001) and a 1.51-fold increased risk of cardiovascular mortality (HR = 1.51, 95% CI 1.04-2.18, P = 0.030) compared to a lower SII. Kaplan-Meier analyses corroborated significantly reduced survival rates within the higher SII cohort for both all-cause and cardiovascular mortality (P < 0.0001 and P = 0.0004). RCS analyses confirmed a positive nonlinear relationship between SII and mortality rates. In conclusion, the SII offers a straightforward indicator of the equilibrium between detrimental innate inflammation and beneficial adaptive immunity. Our investigation, utilizing a comprehensive and nationally representative sample, reveals that elevated SII levels independently forecast a greater risk of mortality from all causes, as well as cardiovascular-specific mortality, in individuals suffering from RA. These insights underscore the clinical relevance of the SII as an affordable and readily accessible biomarker. Its incorporation into regular clinical practice could significantly enhance the precision of risk assessment and forecasting for patients with RA, facilitating more tailored and effective management strategies. Specifically, patients with high SII levels could be identified for more stringent cardiovascular risk management, including closer monitoring, lifestyle interventions, and aggressive pharmacological treatments to mitigate their increased risk of mortality.
Topics: Humans; Arthritis, Rheumatoid; Male; Female; Cardiovascular Diseases; Middle Aged; Inflammation; Nutrition Surveys; Aged; Adult; Cause of Death; Proportional Hazards Models; Risk Factors
PubMed: 38956376
DOI: 10.1038/s41598-024-66152-4 -
Journal For Immunotherapy of Cancer Jul 2024Fludarabine in combination with cyclophosphamide (FC) is the standard lymphodepletion regimen for CAR T-cell therapy (CAR T). A national fludarabine shortage in 2022...
BACKGROUND
Fludarabine in combination with cyclophosphamide (FC) is the standard lymphodepletion regimen for CAR T-cell therapy (CAR T). A national fludarabine shortage in 2022 necessitated the exploration of alternative regimens with many centers employing single-agent bendamustine as lymphodepletion despite a lack of clinical safety and efficacy data. To fill this gap in the literature, we evaluated the safety, efficacy, and expansion kinetics of bendamustine as lymphodepletion prior to axicabtagene ciloleucel (axi-cel) therapy.
METHODS
84 consecutive patients with relapsed or refractory large B-cell lymphoma treated with axi-cel and managed with a uniform toxicity management plan at Stanford University were studied. 27 patients received alternative lymphodepletion with bendamustine while 57 received FC.
RESULTS
Best complete response rates were similar (73.7% for FC and 74% for bendamustine, p=0.28) and there was no significant difference in 12-month progression-free survival or overall survival estimates (p=0.17 and p=0.62, respectively). The frequency of high-grade cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome was similar in both the cohorts. Bendamustine cohort experienced lower proportions of hematological toxicities and antibiotic use for neutropenic fever. Immune reconstitution, as measured by quantitative assessment of cellular immunity, was better in bendamustine cohort as compared with FC cohort. CAR T expansion as measured by peak expansion and area under the curve for expansion was comparable between cohorts.
CONCLUSIONS
Bendamustine is a safe and effective alternative lymphodepletion conditioning for axi-cel with lower early hematological toxicity and favorable immune reconstitution.
Topics: Humans; Bendamustine Hydrochloride; Male; Female; Middle Aged; Aged; Lymphoma, Large B-Cell, Diffuse; Biological Products; Adult; Immunotherapy, Adoptive; Antigens, CD19
PubMed: 38955420
DOI: 10.1136/jitc-2024-008975 -
Journal of the American Chemical Society Jul 2024The messenger RNA (mRNA) vaccines hold great significance in contagion prevention and cancer immunotherapy. However, safely and effectively harnessing innate immunity to...
The messenger RNA (mRNA) vaccines hold great significance in contagion prevention and cancer immunotherapy. However, safely and effectively harnessing innate immunity to stimulate robust and durable adaptive immune protection is crucial, yet challenging. In this study, we synthesized a library of stimuli-responsive bivalent ionizable lipids (srBiv iLPs) with smart molecular blocks responsive to esterase, HO, cytochrome P450, alkaline phosphatase, nitroreductase, or glutathione (GSH), aiming to leverage physiological cues to trigger fast lipid degradation, promote mRNA translation, and induce robust antitumor immunity via reactive oxygen species (ROS)-mediated boosting. After subcutaneous immunization, esterase-responsive vaccine (eBiv-mVac) was rapidly internalized and transported into the draining lymph nodes. It then underwent fast decaging and self-immolative degradation in esterase-rich antigen-presenting cells, releasing sufficient mRNA for antigen translation and massive reactive quinone methides to elevate ROS levels. This resulted in broad activation of innate immunity to boost T cell response, prompting a large number of primed antigen-specific CD8 T cells to circulate and infiltrate into tumors (>1000-fold versus unvaccinated control), thereby orchestrating innate and adaptive immunity to control tumor growth. Moreover, by further combining our vaccination strategy with immune checkpoint blockade, we demonstrated a synergism that significantly amplified the magnitude and function of antigen-specific CD8 T cells. This, in turn, caused potent systemic antitumor efficacy and prolonged survival with high complete response rate in xenograft and metastasis models. Overall, our generalized stimuli-responsive mRNA delivery platform promises a paradigm shift in the design of potent vaccines for cancer immunotherapy, as well as effective and precise carriers for gene editing, protein replacement, and cell engineering.
PubMed: 38955767
DOI: 10.1021/jacs.4c04331 -
JCI Insight Jul 2024Upon infection, naïve CD8+ T cells differentiate into cytotoxic effector cells to eliminate the pathogen-infected cells. Although many mechanisms underlying this...
Upon infection, naïve CD8+ T cells differentiate into cytotoxic effector cells to eliminate the pathogen-infected cells. Although many mechanisms underlying this process have been demonstrated, the regulatory role of chromatin remodel system in this process remains largely unknown. Here we showed that BRD7, a component of the polybromo-associated BRG1-associated factor complex (PBAF), was required for naïve CD8+ T cells to differentiate into functional short-lived effector cells (SLECs) in response to acute infections caused by influenza virus or lymphocytic choriomeningitis virus (LCMV). BRD7-deficiency in CD8+ T cells resulted in profound defects in effector population and functions, thereby impairing viral clearance and host recovery. Further mechanical studies indicated that the expression of BRD7 significantly turned to high from naïve CD8+ T cells to effector cells, bridged BRG1 and PBRM1 to the core module of PBAF complex, consequently facilitating the assembly of PBAF complex rather than BAF complex in the effector cells. The PBAF complex changed the chromatin accessibility at the loci of Tbx21 gene and up-regulated its expression, leading to the maturation of effector T cells. Our research confirms BRD7 and the PBAF complex are key in CD8+ T cell development and present a significant target for advancing immune therapies.
PubMed: 38954484
DOI: 10.1172/jci.insight.171605 -
Cancer Immunology, Immunotherapy : CII Jul 2024Tissue-resident memory CD103+CD8+ T cells (CD103+CD8+ TRMs) are important components of anti-tumor immunity. However, the significance of CD103+CD8+ TRMs in colorectal...
BACKGROUND
Tissue-resident memory CD103+CD8+ T cells (CD103+CD8+ TRMs) are important components of anti-tumor immunity. However, the significance of CD103+CD8+ TRMs in colorectal cancer (CRC) and their advantages remain unclear.
METHODS
Clinical data and specimens were used to evaluate the significance of CD103+CD8+ TRMs in CRC. A mouse subcutaneous tumorigenesis model and colony-formation assay were conducted to evaluate the anti-tumor effects of CD103+CD8+ TRMs. Finally, the infiltration density and function of CD103+CD8+ TRMs in the tumors were evaluated using flow cytometry.
RESULTS
In this study, we showed that highly infiltrated CD103+CD8+ TRMs were associated with earlier clinical stage and negative VEGF expression in CRC patients and predicted a favorable prognosis for CRC/CRC liver metastases patients. Interestingly, we also found that CD103+CD8+ TRMs may have predictive potential for whether CRC develops liver metastasis in CRC. In addition, we found a positive correlation between the ratio of the number of α-SMA+ vessels to the sum of the number of α-SMA+ and CD31+ vessels in CRC, and the infiltration level of CD103+CD8+ TRMs. In addition, anti-angiogenic therapy promoted infiltration of CD103+CD8+ TRMs and enhanced their ability to secrete interferon (IFN)-γ, thus further improving the anti-tumor effect. Moreover, in vivo experiments showed that compared with peripheral blood CD8+ T cells, CD103+CD8+ TRMs infused back into the body could also further promote CD8+ T cells to infiltrate the tumor, and they had a stronger ability to secrete IFN-γ, which resulted in better anti-tumor effects.
CONCLUSION
We demonstrated that CD103+CD8+ TRMs have the potential for clinical applications and provide new ideas for combined anti-tumor therapeutic strategies, such as anti-tumor angiogenesis therapy and CAR-T combined immunotherapy.
Topics: Colorectal Neoplasms; Integrin alpha Chains; Animals; Humans; CD8-Positive T-Lymphocytes; Mice; Liver Neoplasms; Antigens, CD; Prognosis; Female; Male; Immunologic Memory; Biomarkers, Tumor; Memory T Cells; Lymphocytes, Tumor-Infiltrating; Middle Aged
PubMed: 38954030
DOI: 10.1007/s00262-024-03709-2 -
Cancer Immunology, Immunotherapy : CII Jul 2024Tumor immunotherapies targeting PD-(L)1 exhibit anti-tumor efficacy in only 10-30% of patients with various cancers. Literature has demonstrated that a "hot tumor" which...
Tumor immunotherapies targeting PD-(L)1 exhibit anti-tumor efficacy in only 10-30% of patients with various cancers. Literature has demonstrated that a "hot tumor" which contains high T lymphocytes in the tumor microenvironment exhibits a better response to immunotherapies than a "cold tumor." This study aimed to investigate whether tumor-intrinsic IFNα and CXCL10 determine the recruitment and activation of CD8 T cells to become "hot tumor." In this study, we found that CXCL10 overexpressed in a variety of tumors including lung, colon, and liver tumors with a correlation with PD-L1. High PD-L1 and CXCL10 are associated with better survival rates in tumor patients receiving immunotherapies. IFNs-downstream transcriptional factor IRF-1 and STAT1 were correlated with PD-L1 and CXCL10 expression. We demonstrated that IRF-1 and STAT1 were both bound with the promoters of PD-L1 and CXCL10, sharing the same signaling pathway and determining IFNs-mediated PD-L1 and CXCL10 expression. In addition, IFNα significantly increased activation marker IFNγ in PBMCs, promoting M1 type monocyte differentiation, CD4 T, and CD8 T cell activation. Particularly, we found that CD8 T lymphocytes abundantly expressed CXCR3, a receptor of CXCL10, by flow cytometry, indicating that tumor-intrinsic CXCL10 potentially recruited CD8 T in tumor microenvironment. To demonstrate the hypothesis, immunotherapy-sensitive CT26 and immunotherapy-resistant LL/2 were used and we found that CT26 cells exhibited higher IFNα, IFNγ, CXCL10, and PD-L1 levels compared to LL/2, leading to higher IFNγ expression in mouse splenocytes. Moreover, we found that CD8 T cells were recruited by CXCL10 in vitro, whereas SCH546738, an inhibitor of CXCR3, inhibited T cell migration and splenocytes-mediated anti-tumor effect. We then confirmed that CT26-derived tumor was sensitive to αPD-L1 immunotherapy and LL/2-tumor was resistant, whereas αPD-L1 significantly increased T lymphocyte activation marker CD107a in CT26-derived BALB/c mice. In conclusion, this study revealed that CXCL10 expression is correlated with PD-L1 in tumors, sharing the same signaling pathway and associating with better immunotherapeutic efficacy. Further evidence in the syngeneic tumor models demonstrated that immunotherapy-sensitive CT26 intrinsically exhibited higher IFNα and CXCL10 compared to immunotherapy-resistant LL/2 to recruit and activate CD8 T cells in the tumor microenvironment, exhibiting "hot tumor" characteristic of sensitizing αPD-L1 immunotherapies.
Topics: Chemokine CXCL10; Tumor Microenvironment; Animals; Mice; Humans; Interferon-alpha; Immunotherapy; Neoplasms; Lymphocyte Activation; Cell Line, Tumor; CD8-Positive T-Lymphocytes; B7-H1 Antigen; Female; STAT1 Transcription Factor
PubMed: 38953994
DOI: 10.1007/s00262-024-03761-y -
Der Nervenarzt Jul 2024While the neuronal mechanisms of epileptic hyperexcitability (HE) have been studied in detail, recent findings suggest that extraneuronal, mainly immune-mediated... (Review)
Review
OBJECTIVE
While the neuronal mechanisms of epileptic hyperexcitability (HE) have been studied in detail, recent findings suggest that extraneuronal, mainly immune-mediated inflammatory and vascular mechanisms play an important role in the development and progression of HE in epilepsy and the cognitive and behavioral comorbidities.
MATERIAL AND METHODS
Narrative review.
RESULTS
As in autoimmune (limbic) encephalitis (ALE/AIE) or Rasmussen's encephalitis (RE), the primary adaptive and innate immune responses and associated changes in the blood-brain barrier (BBB) and neurovascular unit (NVU) can cause acute cortical hyperexcitability (HE) and the development of hippocampal sclerosis (HS) and other structural cortical lesions with chronic HE. Cortical HE, which is associated with malformation of cortical development (MCD) and low-grade epilepsy-associated tumors (LEAT), for example, can be accompanied by secondary adaptive and innate immune responses and alterations in the BBB and NVU, potentially modulating the ictogenicity and epileptogenicity. These associations illustrate the influence of adaptive and innate immune mechanisms and associated changes in the BBB and NVU on cortical excitability and vice versa, suggesting a dynamic and complex interplay of these factors in the development and progression of epilepsy in general.
DISCUSSION
The described concept of a neuro-immune-vascular interaction in focal epilepsy opens up new possibilities for the pathogenetic understanding and thus also for the selective therapeutic intervention.
PubMed: 38953922
DOI: 10.1007/s00115-024-01695-5 -
Advanced Science (Weinheim,... Jul 2024In situ cancer vaccination is an attractive strategy that stimulates protective antitumor immunity. Cytotoxic T lymphocytes (CTLs) are major mediators of the adaptive...
In situ cancer vaccination is an attractive strategy that stimulates protective antitumor immunity. Cytotoxic T lymphocytes (CTLs) are major mediators of the adaptive immune defenses, with critical roles in antitumor immune response and establishing immune memory, and are consequently extremely important for in situ vaccines to generate systemic and lasting antitumor efficacy. However, the dense extracellular matrix and hypoxia in solid tumors severely impede the infiltration and function of CTLs, ultimately compromising the efficacy of in situ cancer vaccines. To address this issue, a robust in situ cancer vaccine, Au@MnO nanoparticles (AMOPs), based on a gold nanoparticle core coated with a manganese dioxide shell is developed. The AMOPs modulated the unfavorable tumor microenvironment (TME) to restore CTLs infiltration and function and efficiently induced immunogenic cell death. The Mn-mediated stimulator of the interferon genes pathway can be activated to further augment the therapeutic efficacy of the AMOPs. Thus, the AMOPs vaccine successfully elicited long-lasting antitumor immunity to considerably inhibit primary, recurrent, and metastatic tumors. This study not only highlights the importance of revitalizing CTLs efficacy against solid tumors but also makes progress toward overcoming TME barriers for sustained antitumor immunity.
PubMed: 38953329
DOI: 10.1002/advs.202403158 -
Frontiers in Immunology 2024Human Herpesvirus 6B (HHV-6B) impedes host immune responses by downregulating class I MHC molecules (MHC-I), hindering antigen presentation to CD8+ T cells....
INTRODUCTION
Human Herpesvirus 6B (HHV-6B) impedes host immune responses by downregulating class I MHC molecules (MHC-I), hindering antigen presentation to CD8+ T cells. Downregulation of MHC-I disengages inhibitory receptors on natural killer (NK) cells, resulting in activation and killing of the target cell if NK cell activating receptors such as NKG2D have engaged stress ligands upregulated on the target cells. Previous work has shown that HHV-6B downregulates three MHC-like stress ligands MICB, ULBP1, and ULBP3, which are recognized by NKG2D. The U20 glycoprotein of the related virus HHV-6A has been implicated in the downregulation of ULBP1, but the precise mechanism remains undetermined.
METHODS
We set out to investigate the role of HHV-6B U20 in modulating NK cell activity. We used HHV-6B U20 expressed as a recombinant protein or transduced into target cells, as well as HHV-6B infection, to investigate binding interactions with NK cell ligands and receptors and to assess effects on NK cell activation. Small-angle X-ray scattering was used to align molecular models derived from machine-learning approaches.
RESULTS
We demonstrate that U20 binds directly to ULBP1 with sub-micromolar affinity. Transduction of U20 decreases NKG2D binding to ULBP1 at the cell surface but does not decrease ULBP1 protein levels, either at the cell surface or in toto. HHV-6B infection and soluble U20 have the same effect. Transduction of U20 blocks NK cell activation in response to cell-surface ULBP1. Structural modeling of the U20 - ULBP1 complex indicates some similarities to the m152-RAE1γ complex.
Topics: Humans; Killer Cells, Natural; Herpesvirus 6, Human; GPI-Linked Proteins; NK Cell Lectin-Like Receptor Subfamily K; Lymphocyte Activation; Protein Binding; Viral Proteins; Glycoproteins; Intracellular Signaling Peptides and Proteins
PubMed: 38953028
DOI: 10.3389/fimmu.2024.1363156