scholarly journals Combination Immune Treatment of a Highly Aggressive Orthotopic Murine Glioblastoma With Checkpoint Blockade Inhibition and Neoantigen Vaccination

Neurosurgery ◽  
2019 ◽  
Vol 66 (Supplement_1) ◽  
Author(s):  
Connor Liu ◽  
Maximilian Schaettler ◽  
Jay Bowman-Kirigin ◽  
Diane Bender ◽  
Dale K Kobayashi ◽  
...  

Abstract INTRODUCTION The treatment of glioblastoma remains a challenge for modern therapy. Checkpoint blockade inhibitors (CBI), designed to block inhibitory T-cell signaling, represent attractive potential therapeutic interventions. However, glioblastoma response rates to CBI remain low. To this end, preclinical models are critical to studying multi-modal immune interventions to overcome CBI resistance. Therefore, we set out to identify endogenous neoantigens in a CBI resistant murine glioblastoma and assess the efficacy of neoantigen vaccination in combination with CBI treatment. METHODS Whole exome DNA and RNA sequencing was used to identify expressed, missense mutations in the C57BL/6 derived murine glioblastoma, CT2A. The pVAC-seq software suite was used to identify candidate neoantigens predicted to bind H2-Kb and H2-Db molecules. CD8 + T cells isolated from CT2A tumor-infiltrating lymphocytes (TIL) were screened for neoantigen reactivity by IFN-gamma enzyme linked immunospot assays. Survival analysis was performed on intracranial tumor bearing mice treated with neoantigen vaccination, anti-PD-L1, or combination therapy. RESULTS In silico analysis identified 649 CT2A-derived candidate neoantigens predicted to bind H2-Kb or H2-Db molecules. Of the 40 top-ranking neoantigen candidates, 16 elicited CD8 + TIL responses in mice vaccinated with cognate peptides. Assessing for endogenous reactivity, we identified neoantigen specific CD8 + T cell responses in the intracranial TIL and draining lymph nodes to two H2-Kb restricted, Epb4 (H471L) and Pomgnt1 (R497L), and one H2-Db restricted neoantigen, Plin2 (G332R). Survival studies showed that therapeutic neoantigen vaccination with Epb4, Pomgnt1, and Plin2, in combination with anti-PD-L1 treatment was superior to anti-PD-L1 alone. CONCLUSION We identified endogenous neoantigen specific CD8 + T cells within brain tumors and draining lymph nodes of a CBI resistant murine glioblastoma. Furthermore, we find that neoantigen vaccination significantly augments survival benefit in combination with anti-PD-L1 treatment. These observations provide important preclinical correlates for glioblastoma immunotherapy trials and support further investigation into the effects of multi-modal immunotherapeutic interventions on anti-glioma immunity.

2008 ◽  
Vol 80 (1) ◽  
pp. 129-136 ◽  
Author(s):  
Wânia F. Pereira ◽  
Landi V.C. Guillermo ◽  
Flávia L. Ribeiro-Gomes ◽  
Marcela F. Lopes

Following infection with Leishmania major, T cell activation and apoptosis can be detected in draining lymph nodes of C57BL/6-infected mice. We investigated the mechanisms involved in apoptosis and cytokine expression following Tcellactivation. After two weeks of infection, apoptotic T cells were not detected in draining lymph nodes but activation with anti-CD3 induced apoptosis in both CD4 and CD8 T cells. Treatment with anti-FasLigand, caspase-8 or caspase- 9 inhibitors did not block activation-induced T-cell death. We also investigated whether the blockade of caspase-8 activity would affect the expression of type-1 or type-2 cytokines. At early stages of infection, both CD4 and CD8 T cells expressed IFN-gamma upon activation. Treatment with the caspase-8 inhibitor zIETD-fmk (benzyl-oxycarbonyl-Ile- Glu(OMe)-Thr-Asp(OMe)-fluoromethyl ketone) reduced the proportion of CD8 T cells and IFN-gamma expression in both CD4 and CD8T cells. We conclude that a non apoptotic role of caspase-8 activity may be required for T cell-mediated type-1 responses during L. major infection.


Cancers ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 4616
Author(s):  
Yasuhiro Kanda ◽  
Taku Okazaki ◽  
Tomoya Katakai

The migration status of T cells within the densely packed tissue environment of lymph nodes reflects the ongoing activation state of adaptive immune responses. Upon encountering antigen-presenting dendritic cells, actively migrating T cells that are specific to cognate antigens slow down and are eventually arrested on dendritic cells to form immunological synapses. This dynamic transition of T cell motility is a fundamental strategy for the efficient scanning of antigens, followed by obtaining the adequate activation signals. After receiving antigenic stimuli, T cells begin to proliferate, and the expression of immunoregulatory receptors (such as CTLA-4 and PD-1) is induced on their surface. Recent findings have revealed that these ‘immune checkpoint’ molecules control the activation as well as motility of T cells in various situations. Therefore, the outcome of tumor immunotherapy using checkpoint inhibitors is assumed to be closely related to the alteration of T cell motility, particularly in tumor-draining lymph nodes (TDLNs). In this review, we discuss the migration dynamics of T cells during their activation in TDLNs, and the roles of checkpoint molecules in T cell motility, to provide some insight into the effect of tumor immunotherapy via checkpoint blockade, in terms of T cell dynamics and the importance of TDLNs.


Blood ◽  
2006 ◽  
Vol 108 (7) ◽  
pp. 2257-2264 ◽  
Author(s):  
Sophie Laffont ◽  
Jérôme D. Coudert ◽  
Lucile Garidou ◽  
Laurent Delpy ◽  
Aurélie Wiedemann ◽  
...  

Abstract Accumulating evidence indicates that, in absence of CD8+ T-cell activation, CD4+ T-cell–mediated allograft rejection is associated with a dominant Th2-cell response and eosinophil infiltrates. In this study, we analyzed the mechanisms by which CD8+ T cells regulate alloreactive CD4+ T-cell priming and differentiation into interleukin 4 (IL-4)–producing cells. We showed that interferon γ (IFN-γ) production by CD8+ T cells was dispensable for the inhibition of Th2-cell development, as well as tissue eosinophilia and type 2 cytokine production in the rejected grafts. Since we noticed that CD8+ T cells not only suppressed Th2 differentiation, but also down-modulated the overall priming of alloreactive CD4+ T cells, we evaluated whether CD8+ T cells act by limiting the accumulation of donor-derived dendritic cells (DCs) in lymph nodes. We found that indeed, alloreactive CD8+ T cells rapidly eliminated allogeneic DCs from T-cell areas of draining lymph nodes, through a perforin-dependent mechanism. Thus, our data demonstrate that cytotoxic T lymphocyte (CTL)–mediated clearance of allogeneic DCs is a negative feedback mechanism that limits the duration of alloantigen presentation in draining lymph nodes, thereby modulating the amplitude and polarization of the primary alloreactive CD4+ T-cell responses.


Author(s):  
Jens Blobner ◽  
Michael Kilian ◽  
Chin Leng Tan ◽  
Katrin Aslan ◽  
Khwab Sanghvi ◽  
...  

Abstract Background Glioblastomas, the most common primary malignant brain tumors, are considered immunologically cold malignancies due to growth in an immune sanctuary site. While peptide vaccines have shown to generate intra-tumoral antigen-specific T cells, the identification of these tumor-specific T cells is challenging and requires detailed analyses of tumor tissue. Several studies have shown that CNS antigens may be transported via lymphatic drainage to cervical lymph nodes, where antigen-specific T cell responses can be generated. Therefore, we investigated whether glioma-draining lymph nodes (TDLN) may constitute a reservoir of tumor-reactive T cells. Methods We addressed our hypothesis by flow cytometric analyses of chicken ovalbumin (OVA)-specific CD8 + T cells as well as T cell receptor beta (TCRβ) next-generation-sequencing (TCRβ-NGS) of T cells from tumor tissue, TDLN, spleen, and inguinal lymph nodes harvested from experimental mouse GL261 glioma models. Results Longitudinal dextramer-based assessment of specific CD8 + T cells from TDLN did not show tumor model antigen reactivity. Unbiased immunogenomic analysis revealed a low overlap of TCRβ sequences from glioma-infiltrating CD8 + T cells between mice. Enrichment-scores, calculated by the ratio of productive frequencies of the different TCRβ-CDR3 amino-acid (aa) rearrangements of CD8 + T cells derived from tumor, TDLN, inguinal lymph nodes, and spleen demonstrated a higher proportion of tumor-associated TCR in the spleen compared to TDLN. Conclusions In experimental glioblastoma, our data did not provide evidence that glioma-draining cervical lymph nodes are a robust reservoir for spontaneous glioma-specific T cells highlighting the requirement of detailed analyses of glioma-infiltrating T cells for the discovery of tumor-specific TCR.


2015 ◽  
Vol 135 (4) ◽  
pp. 1007-1015 ◽  
Author(s):  
Satoshi Nakamizo ◽  
Gyohei Egawa ◽  
Michio Tomura ◽  
Shunsuke Sakai ◽  
Soken Tsuchiya ◽  
...  

2009 ◽  
Vol 84 (4) ◽  
pp. 2078-2089 ◽  
Author(s):  
Shawn D. Blackburn ◽  
Alison Crawford ◽  
Haina Shin ◽  
Antonio Polley ◽  
Gordon J. Freeman ◽  
...  

ABSTRACT The PD-1/PD-L pathway plays a major role in regulating T-cell exhaustion during chronic viral infections in animal models, as well as in humans, and blockade of this pathway can revive exhausted CD8+ T cells. We examined the expression of PD-1 and its ligands, PD-L1 and PD-L2, in multiple tissues during the course of chronic viral infection and determined how the amount of PD-1 expressed, as well as the anatomical location, influenced the function of exhausted CD8 T cells. The amount of PD-1 on exhausted CD8 T cells from different anatomical locations did not always correlate with infectious virus but did reflect viral antigen in some tissues. Moreover, lower expression of PD-L1 in some locations, such as the bone marrow, favored the survival of PD-1Hi exhausted CD8 T cells, suggesting that some anatomical sites might provide a survival niche for subpopulations of exhausted CD8 T cells. Tissue-specific differences in the function of exhausted CD8 T cells were also observed. However, while cytokine production did not strictly correlate with the amount of PD-1 expressed by exhausted CD8 T cells from different tissues, the ability to degranulate and kill were tightly linked to PD-1 expression regardless of the anatomical location. These observations have implications for human chronic infections and for therapeutic interventions based on blockade of the PD-1 pathway.


2021 ◽  
Vol 12 ◽  
Author(s):  
Lilja Hardardottir ◽  
Maria Victoria Bazzano ◽  
Laura Glau ◽  
Luca Gattinoni ◽  
Angela Köninger ◽  
...  

CD8+ T cells are the most frequent T cell population in the immune cell compartment at the feto-maternal interface. Due to their cytotoxic potential, the presence of CD8+ T cells in the immune privileged pregnant uterus has raised considerable interest. Here, we review our current understanding of CD8+ T cell biology in the uterus of pregnant women and discuss this knowledge in relation to a recently published immune cell Atlas of human decidua. We describe how the expansion of CD8+ T cells with an effector memory phenotype often presenting markers of exhaustion is critical for a successful pregnancy, and host defense towards pathogens. Moreover, we review new evidence on the presence of long-lasting immunological memory to former pregnancies and discuss its impact on prospective pregnancy outcomes. The formation of fetal-specific memory CD8+ T cell subests in the uterus, in particular of tissue resident, and stem cell memory cells requires further investigation, but promises interesting results to come. Advancing the knowledge of CD8+ T cell biology in the pregnant uterus will be pivotal for understanding not only tissue-specific immune tolerance but also the etiology of complications during pregnancy, thus enabling preventive or therapeutic interventions in the future.


2021 ◽  
Author(s):  
To-Ha Thai ◽  
Phuong Le ◽  
Ngoc Ha ◽  
Ngan Tran ◽  
Andrew Newman ◽  
...  

Abstract Checkpoint blockade can reverse CD8+ T-cell functional exhaustion, and TCF-1 is essential for this process. However, identifying mechanisms that can prevent functional senescence and potentiate CD8+ T-cell persistence in checkpoint blockade non-responsive tumors remains a challenge. We demonstrate that targeting Cbx3/HP1γ causes augmented transcription initiation, chromatin remodeling at Lef1 and Il21r leading to increased transcriptional activity at these loci. Mechanistic studies show LEF-1 and IL-21R are required for Cbx3/HP1γ-deficient CD8+ effector T cells to persist resulting in improved control of ovarian cancer, melanoma and neuroblastoma in pre-clinical models. Cbx3/HP1γ-deficient CD8+ T cells enhanced persistence in the TME facilitates remodeling of the chemokine/receptor landscape that ensures their optimal tumor invasion at the expense of CD4+ Tregs. Thus, CD8+ T cells heightened effector function consequent to Cbx3/HP1γ deficiency may be distinct from functional reactivation by checkpoint blockade, implicating Cbx3/HP1γ as a viable cancer T-cell-based therapy target for resistant, non-responsive solid tumors.


2021 ◽  
Author(s):  
◽  
Sabine Kuhn

<p><b>The anti-tumour immune response is often not potent enough to prevent or eradicate disease. Dendritic cells (DCs) are professional antigen-presenting cells that are critical for the initiation of immune responses. While DCs frequently infiltrate tumours, lack of activation together with immuno-suppressive factors from the tumour can hamper an effective anti-tumour immune response.</b></p> <p>In this thesis, the ability of microbial stimuli and danger signals to overcome suppression and re-programme DCs and macrophages to an immuno-stimulatory phenotype was investigated. Whole live Mycobacterium smegmatis and BCG were used to provide multiple pathogen-associated molecular patterns. The intracellularly-recognised toll-like-receptor (TLR) ligands CpG and Poly IC, as well as the extracelullarly recognised TLR ligand LPS, and the danger signal monosodium-urate crystals (MSU) were also included.</p> <p>Bone-marrow derived DCs were found to respond to all adjuvants in vitro and DCs in tumour cell suspensions could be activated ex vivo. To assess the ability of adjuvants to enhance anti-tumour responses in vivo, immune-competent mice bearing established subcutaneous B16F1 melanomas were injected peri-tumorally with the different adjuvants. In line with previous reports, CpG treatment was effective in delaying tumour growth and increasing survival. A similar effect was found with Poly IC, but not with LPS, M. smegmatis, BCG or MSU alone. Combination of M. smegmatis + MSU, however, significantly delayed tumour growth and prolonged survival, while combinations of MSU + BCG or LPS were ineffective. Similar results were obtained using the B16.OVA melanoma and E.G7-OVA thymoma subcutaneous tumour models. In addition, Poly IC and MSU + M. smegmatis reduced primary tumour growth as well as lung metastases in the orthotopic 4T1 breast carcinoma model.</p> <p>Both Poly IC and MSU + M. smegmatis elicited an anti-tumour immune response that required CD8 T cells as well as NK cells. These treatments also resulted in increased proliferation of CD8 T cells and NK cells in tumour-draining lymph nodes, augmented infiltration of effector cells into the tumour, as well as enhanced production of in ammatory cytokines by effector cells and DCs in tumours. In addition, MSU + M. smegmatis also stimulated CD4 T cell proliferation, tumour-infiltrationand activation, while at the same time decreasing the frequency of regulatory T cells in tumours.</p> <p>Activation of a successful immune response to tumours was associated with early induction of IL-12 and IFNʸ, as well as moderate levels of pro-inflammatory cytokines at the tumour site and systemically. Furthermore, anti-tumour activity correlated with the induction of inflammatory monocyte-derived DCs in tumour-draining lymph nodes. These DCs were also observed in adjuvant treated tumours and their appearance was preceded by accumulation of inflammatory monocytes at the tumour site.</p> <p>These findings suggest that specific natural adjuvants can successfully modify the tumour environment and enhance the innate and adaptive anti-tumour immune response to delay tumour progression and increase survival.</p>


2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi104-vi104
Author(s):  
Elizabeth Ogando-Rivas ◽  
Paul Castillo ◽  
Noah Jones ◽  
Vrunda Trivedi ◽  
Jeffrey Drake ◽  
...  

Abstract BACKGROUND Adoptive T-cell therapies have been successfully used as treatment for patients diagnosed with advanced cancers. Unfortunately, for some refractory cancers, they have failed. To overcome this, checkpoint inhibitors have shown to rescue immune anti-tumor responses. We hypothesized that in-vitro checkpoint blockade during T-cell stimulation and expansion with RNA-pulsed dendritic cells may enhance the activity of antigen-specific T-cells and improve the efficacy of ACT platforms. METHODS Human PBMCs were isolated from CMV seropositive donors to generate DCs and pulsed them with CMVpp65-mRNA to educate T-cells in co-culture for 15-days. We targeted pp65 antigen which is ubiquitously expressed by glioblastoma cells. Three checkpoint blockade conditions were evaluated (anti-PD1, anti-Tim3 and anti-PD1+Tim3). IL2 was added every 3 days as well as the blockade antibodies. Immunephenotyping was performed on Day-0 and Day-15. Polyfunctional antigen specific responses were evaluated upon rechallenge with CMVpp65 peptides. RESULTS CMVpp65 activated CD8+ T-cells upregulate Lag3 and Tim3 (p= &lt; 0.0001). Tim3 blockade alone or in combination led to a significant upregulation of Lag3 expression on CD8+pp65Tetramer+ central memory, effector memory, and TEMRA T-cells. This latter T-cell subset uniquely maintain double-positive Tim3/Lag3 expression after blockade. In contrast, PD-1 blockade had minimal effects on Tim3 or Lag3 expression. In addition, IFN-g secretion was reduced in T-cells treated with Tim3 blockade in a dose-dependent manner (p= 0.004). CONCLUSION In this study, we have identified a potential activating component of Tim3 and linkage between Tim3 and Lag3 signaling upon blocking Tim3 axis during T-cell antigen presenting cell interactions that should be considered when targeting immune checkpoints for clinical use.


Sign in / Sign up

Export Citation Format

Share Document