Search

T lymphocytes that infiltrate the tumor microenvironment (TME) often fail to function as effective anti-cancer agents. Within the TME, cell-to-cell inhibitory interactions play significant roles in dampening their anti-tumor activities. Recent studies have revealed that soluble factors released in the TME by immune and non-immune cells, as well as by tumor cells themselves, contribute to the exacerbation of T cell exhaustion. Our understanding of the cytokine landscape of the TME, their interrelationships, and their impact on cancer development is still at its early stages. In this review, we aim to shed light on Interleukin (IL) -6, IL-9, and IL-10, a small group of JAK/STAT signalingdependent cytokines harboring T cell-suppressive effects in the TME and summarize their mechanisms of action. Additionally, we will explore how advancements in scientific research can help us overcoming the obstacles posed by cytokines that suppress T cells in tumors, with the ultimate objective of stimulating further investigations for the development of novel therapeutic strategies to counteract their tumor-promoting activities. [ABSTRACT FROM AUTHOR]

Simple Summary: Immune checkpoint inhibitors (ICIs) are cancer immunotherapeutics that reinvigorate immune cells' ability to attack tumor cells. Despite remarkable results in some patients, ICIs do not demonstrate the same efficacy across all individuals. In this study, we present the first side-by-side comparison of an agent-based model (ABM) with an ordinary differential equation (ODE) model for ICIs targeting the PD-1/PD-L1 immune checkpoint. We consider tumor cells of high and low antigenicity and two distinct immune-cell kill mechanisms. Using key parameters calibrated from mouse bladder cancer studies, we simulate virtual tumors using both models. Our research identifies crucial tumor-immune characteristics that influence the efficacy of ICIs. By exploring the unique spatial insights provided by the ABM, we underscore the importance of considering the spatial complexity of the tumor microenvironment in mathematical models of ICIs, potentially paving the way for more effective cancer treatments. Since the introduction of the first immune checkpoint inhibitor (ICI), immunotherapy has changed the landscape of molecular therapeutics for cancers. However, ICIs do not work equally well on all cancers and for all patients. There has been a growing interest in using mathematical and computational models to optimize clinical responses. Ordinary differential equations (ODEs) have been widely used for mechanistic modeling in immuno-oncology and immunotherapy. They allow rapid simulations of temporal changes in the cellular and molecular populations involved. Nonetheless, ODEs cannot describe the spatial structure in the tumor microenvironment or quantify the influence of spatially-dependent characteristics of tumor-immune dynamics. For these reasons, agent-based models (ABMs) have gained popularity because they can model more detailed phenotypic and spatial heterogeneity that better reflect the complexity seen in vivo. In the context of anti-PD-1 ICIs, we compare treatment outcomes simulated from an ODE model and an ABM to show the importance of including spatial components in computational models of cancer immunotherapy. We consider tumor cells of high and low antigenicity and two distinct cytotoxic T lymphocyte (CTL) killing mechanisms. The preferred mechanism differs based on the antigenicity of tumor cells. Our ABM reveals varied phenotypic shifts within the tumor and spatial organization of tumor and CTLs despite similarities in key immune parameters, initial simulation conditions, and early temporal trajectories of the cell populations. [ABSTRACT FROM AUTHOR]

Multiple infections enable the recombination of different strains, which may contribute to viral diversity. How multiple infections affect the competition dynamics between the two types of strains, the wild and the immune escape mutant, remains poorly understood. This study develops a novel mathematical model that includes the two strains, two modes of viral infection, and multiple infections. For the representative double-infection case, the reproductive numbers are derived and global stabilities of equilibria are obtained via the Lyapunov direct method and theory of limiting systems. Numerical simulations indicate similar viral dynamics regardless of multiplicities of infections though the competition between the two strains would be the fiercest in the case of quadruple infections. Through sensitivity analysis, we evaluate the effect of parameters on the set-point viral loads in the presence and absence of multiple infections. The model with multiple infections predict that there exists a threshold for cytotoxic T lymphocytes (CTLs) to minimize the overall viral load. Weak or strong CTLs immune response can result in high overall viral load. If the strength of CTLs maintains at an intermediate level, the fitness cost of the mutant is likely to have a significant impact on the evolutionary dynamics of mutant viruses. We further investigate how multiple infections alter the viral dynamics during the combination antiretroviral therapy (cART). The results show that viral loads may be underestimated during cART if multiple-infection is not taken into account. [ABSTRACT FROM AUTHOR]

The recognition by cytotoxic T cells (CTLs) is essential for the clearance of SARS-CoV-2 virus-infected cells. Several viral proteins have been described to be recognized by CTLs. Among them, the spike (S) protein is one of the immunogenic proteins. The S protein acts as a ligand for its receptors, and several mutants with different affinities for its cognate receptors have been reported, and certain mutations in the S protein, such as L452R and Y453F, have been found to inhibit the HLA-A24-restricted CTL response. In this study, we conducted a screening of candidate peptides derived from the S protein, specifically targeting those carrying the HLA-A24 binding motif. Among these peptides, we discovered that NF9 (NYNYLYRLF) represents an immunogenic epitope. CTL clones specific to the NF9 peptide were successfully established. These CTL clones exhibited the ability to recognize endogenously expressed NF9 peptide. Interestingly, the CTL clone demonstrated cross-reactivity with the Y453F peptide (NYNYLFRLF) but not with the L452R peptide (NYNYRYRLF). The CTL clone was able to identify the endogenously expressed Y453F mutant peptide. These findings imply that the NF9-specific CTL clone possesses the capability to recognize and respond to the Y453F mutant peptide. [ABSTRACT FROM AUTHOR]

AbstractThe recognition by cytotoxic T cells (CTLs) is essential for the clearance of SARS-CoV-2 virus-infected cells. Several viral proteins have been described to be recognized by CTLs. Among them, the spike (S) protein is one of the immunogenic proteins. The S protein acts as a ligand for its receptors, and several mutants with different affinities for its cognate receptors have been reported, and certain mutations in the S protein, such as L452R and Y453F, have been found to inhibit the HLA-A24-restricted CTL response. In this study, we conducted a screening of candidate peptides derived from the S protein, specifically targeting those carrying the HLA-A24 binding motif. Among these peptides, we discovered that NF9 (NYNYLYRLF) represents an immunogenic epitope. CTL clones specific to the NF9 peptide were successfully established. These CTL clones exhibited the ability to recognize endogenously expressed NF9 peptide. Interestingly, the CTL clone demonstrated cross-reactivity with the Y453F peptide (NYNYLFRLF) but not with the L452R peptide (NYNYRYRLF). The CTL clone was able to identify the endogenously expressed Y453F mutant peptide. These findings imply that the NF9-specific CTL clone possesses the capability to recognize and respond to the Y453F mutant peptide.

Immunotherapy using immune checkpoint inhibitors (ICIs) has shown superior efficacy compared with conventional chemotherapy in certain cancer types, establishing immunotherapy as the fourth standard treatment alongside surgical intervention, chemotherapy, and radiotherapy. In cancer immunotherapy employing ICIs, CD8‐positive cytotoxic T lymphocytes are recognized as the primary effector cells. For effective clinical outcomes, it is essential that the targeted cancer cells express HLA class I molecules to present antigenic peptides derived from the tumor. However, cancer cells utilize various mechanisms to downregulate or lose HLA class I molecules from their surface, resulting in evasion from immune surveillance. Correlations between prognosis and the integrity of HLA class I molecules expressed by cancer cells have been consistently found across different types of cancer. This paper provides an overview of the regulatory mechanisms of HLA class I molecules and their role in cancer immunotherapy, with a particular emphasis on the significance of utilizing pathological tissues to evaluate HLA class I molecules expressed in cancer cells. [ABSTRACT FROM AUTHOR]

Identification of cytotoxic T lymphocyte (CTL) epitopes from tumor related antigens is a promising approach for malignant tumor immunotherapy. TC2N, a recently identified tumor associated antigen from human glioblastoma, is regarded as a promising target of tumor-specific immunotherapy. As one of the most widely used histocompatibility molecules in Chinese is HLA-Ap0201, we were able to identify the TC2N peptides that are provided by this molecular type. A panel of antigenic peptides produced from TC2N were predicted by using a computer tool. The binding affinities of three peptides with the highest predicted score to the HLA-Ap0201 molecule were evaluated after synthesis. In vitro and in vivo stimulation of the main T-cell response against the predicted peptides. The results demonstrated that TC2N (152-160) was able to release IFN-? and lyse U251 cells in vitro as well as in vivo by eliciting peptide-specific CTLs. Our results indicated that peptide TC2N (152-160) (RLYGSVCDL) was a novel HLA-A2.1-restricted CTL epitope capable of inducing TC2N specific CTLs in vitro. As TC2N might qualify as a viable target for immunotherapeutic approaches for patients with GBM, we speculated that the newly identified epitope RLYGSVCDL would be of potential use in peptide-based, cancer-specific immunotherapy against GBM. [ABSTRACT FROM AUTHOR]

T lymphocytes that infiltrate the tumor microenvironment (TME) often fail to function as effective anti-cancer agents. Within the TME, cell-to-cell inhibitory interactions play significant roles in dampening their anti-tumor activities. Recent studies have revealed that soluble factors released in the TME by immune and non-immune cells, as well as by tumor cells themselves, contribute to the exacerbation of T cell exhaustion. Our understanding of the cytokine landscape of the TME, their interrelationships, and their impact on cancer development is still at its early stages. In this review, we aim to shed light on Interleukin (IL) -6, IL-9, and IL-10, a small group of JAK/STAT signaling-dependent cytokines harboring T cell-suppressive effects in the TME and summarize their mechanisms of action. Additionally, we will explore how advancements in scientific research can help us overcoming the obstacles posed by cytokines that suppress T cells in tumors, with the ultimate objective of stimulating further investigations for the development of novel therapeutic strategies to counteract their tumor-promoting activities.

Abstract Background A minute fraction of patients stands to derive substantial benefits from immunotherapy, primarily attributable to immune evasion. Our objective was to formulate a predictive signature rooted in genes associated with cytotoxic T lymphocyte evasion (CERGs), with the aim of predicting outcomes and discerning immunotherapeutic response in colorectal cancer (CRC). Methods 101 machine learning algorithm combinations were applied to calculate the CERGs prognostic index (CERPI) under the cross−validation framework, and patients with CRC were separated into high− and low−CERPI groups. Relationship between immune cell infiltration levels, immune−related scores, malignant phenotypes and CERPI were further analyzed. Various machine learning methods were used to identify key genes related to both patient survival and immunotherapy benefits. Expression of HOXC6, G0S2, and MX2 was evaluated and the effects of HOXC6 and G0S2 on the viability and migration of a CRC cell line were in−vitro verified. Results The CERPI demonstrated robust prognostic efficacy in predicting the overall survival of CRC patients, establishing itself as an independent predictor of patient outcomes. The low−CERPI group exhibited elevated levels of immune cell infiltration and lower scores for tumor immune dysfunction and exclusion, indicative of a greater potential benefit from immunotherapy. Moreover, there was a positive correlation between CERPI levels and malignant tumor phenotypes, suggesting that heightened CERPI expression contributes to both the occurrence and progression of tumors. Thirteen key genes were identified, and their expression patterns were scrutinized through the analysis of single−cell datasets. Notably, HOXC6, G0S2, and MX2 exhibited upregulation in both CRC cell lines and tissues. Subsequent knockdown experiments targeting G0S2 and HOXC6 resulted in a significant suppression of CRC cell viability and migration. Conclusion We developed the CERPI for effectively predicting survival and response to immunotherapy in patients, and these results may provide guidance for CRC diagnosis and precise treatment.

Tumor immune escape refers to the inability of the immune system to clear tumor cells, which is one of the major obstacles in designing effective treatment schemes for cancer diseases. Although clinical studies have led to promising treatment outcomes, it is imperative to design theoretical models to investigate the long-term treatment effects. In this paper, we develop a mathematical model to study the interactions among tumor cells, immune escape tumor cells, and T lymphocyte. The chimeric antigen receptor (CAR) T-cell therapy is also described by the mathematical model. Bifurcation analysis shows that there exists backward bifurcation and saddle-node bifurcation when the immune intensity is used as the bifurcation parameter. The proposed model also exhibits bistability when its parameters are located between the saddle-node threshold and backward bifurcation threshold. Sensitivity analysis is performed to illustrate the effects of different mechanisms on the backward bifurcation threshold and basic immune reproduction number. Simulation studies confirm the bifurcation analysis results and predict various types of treatment outcomes using different CAR T-cell therapy strengths. Analysis and simulation results show that the immune intensity can be used to control the tumor size, but it has no effect on the control of the immune escape tumor size. The introduction of the CAR T-cell therapy will reduce the immune escape tumor size and the treatment effect depends on the CAR T-cell therapy strength. [ABSTRACT FROM AUTHOR]

Background: A minute fraction of patients stands to derive substantial benefits from immunotherapy, primarily attributable to immune evasion. Our objective was to formulate a predictive signature rooted in genes associated with cytotoxic T lymphocyte evasion (CERGs), with the aim of predicting outcomes and discerning immunotherapeutic response in colorectal cancer (CRC). Methods: 101 machine learning algorithm combinations were applied to calculate the CERGs prognostic index (CERPI) under the cross−validation framework, and patients with CRC were separated into high− and low−CERPI groups. Relationship between immune cell infiltration levels, immune−related scores, malignant phenotypes and CERPI were further analyzed. Various machine learning methods were used to identify key genes related to both patient survival and immunotherapy benefits. Expression of HOXC6, G0S2, and MX2 was evaluated and the effects of HOXC6 and G0S2 on the viability and migration of a CRC cell line were in−vitro verified. Results: The CERPI demonstrated robust prognostic efficacy in predicting the overall survival of CRC patients, establishing itself as an independent predictor of patient outcomes. The low−CERPI group exhibited elevated levels of immune cell infiltration and lower scores for tumor immune dysfunction and exclusion, indicative of a greater potential benefit from immunotherapy. Moreover, there was a positive correlation between CERPI levels and malignant tumor phenotypes, suggesting that heightened CERPI expression contributes to both the occurrence and progression of tumors. Thirteen key genes were identified, and their expression patterns were scrutinized through the analysis of single−cell datasets. Notably, HOXC6, G0S2, and MX2 exhibited upregulation in both CRC cell lines and tissues. Subsequent knockdown experiments targeting G0S2 and HOXC6 resulted in a significant suppression of CRC cell viability and migration. Conclusion: We developed the CERPI for effectively predicting survival and response to immunotherapy in patients, and these results may provide guidance for CRC diagnosis and precise treatment. [ABSTRACT FROM AUTHOR]

The treatment of human immunodeficiency virus (HIV-1) has evolved since the establishment of combination antiretroviral therapy (ART) in the 1990s, providing HIV-infected individuals with approaches that suppress viral replication, prevent acquired immunodeficiency syndrome (AIDS) throughout their lifetime with continuous therapy, and halt HIV transmission. However, despite the success of these regimens, the global HIV epidemic persists, prompting a comprehensive exploration of potential strategies for an HIV cure. Here, we offer a consolidated overview of cell-based therapies for HIV-1, focusing on CAR-T cell approaches, gene editing, and immune modulation. Persistent challenges, including CAR-T cell susceptibility to HIV infection, stability, and viral reservoir control, underscore the need for continued research. This review synthesizes current knowledge, highlighting the potential of cellular therapies to address persistent challenges in the pursuit of an HIV cure. [ABSTRACT FROM AUTHOR]

Epithelial–mesenchymal transition (EMT) is a dynamic program crucial for organismal development and tissue regeneration. Unfortunately, this program is often hijacked by epithelial tumors to facilitate metastasis. Beyond its role in cancer spread, EMT increases cancer cell survival by activating stem cell programs and bypassing apoptotic programs. Importantly, the capacity of EMT to enforce tumor progression by altering the tumor cell phenotype without triggering immune responses opens the intriguing possibility of a mechanistic link between EMT-driven cancers and immune evasion. Indeed, EMT has been acknowledged as a of driver immune evasion, but the mechanisms are still evolving. Here, we review recent insights into the influence of EMT on tumor immune evasion. Specifically, we focus on the mechanistic roles of EMT in immune escape as the basis that may provide a platform for innovative therapeutic approaches in advanced tumors. We summarize promising therapeutic approaches currently in clinical trials and trending preclinical studies aimed at reinvigorating the tumor microenvironment to create immune-permissive conditions that facilitates immune-mediated tumor clearance. We anticipate that this will assist researchers and pharmaceutical companies in understanding how EMT compromises the immune response, potentially paving the way for effective cancer therapies. [ABSTRACT FROM AUTHOR]

This study investigated the immunological features and therapeutic potential of extracellular vesicle-like nanoparticles isolated from the marine macroalgae Sargassum fusiforme (SF-NPs). SF-NPs were approximately 266.4 nm in size, and comprehensive metabolomic analysis revealed 38 metabolites. SF-NPs can upregulate dendritic cell (DC) maturation markers, increase pro-inflammatory cytokine production, and enhance antigen presentation capacity. DC maturation is regulated by the mitogen-activated protein kinase and nuclear factor-kappa B pathways. Notably, SF-NPs-primed DCs orchestrated robust CD4+ and CD8+ T-cell proliferation, fostering potent Type 1 T-helper (Th1) responses and cytotoxic T lymphocyte (CTL) activity. In a cyclophosphamide-induced immunosuppression mouse model, SF-NPs restored and activated immune cell populations, including DCs, natural killer, CD4+ T, and CD8+ T cells. SF-NPs reversed cyclophosphamide-induced Type 2 T-helper and regulatory T cell-biased responses, favoring Th1 and CTL responses, including multifunctional T cell responses. This study highlighted the potential of SF-NPs as therapeutic candidates for diseases requiring Th1 and CTL responses.

Epstein‒Barr virus (EBV) is a human herpes virus that is saliva-transmissible and universally asymptomatic. It has been confirmed that more than 90% of the population is latently infected with EBV for life. EBV can cause a variety of related cancers, such as nasopharyngeal carcinoma, diffuse large B-cell lymphoma, and Burkitt lymphoma. Currently, many clinical studies have demonstrated that EBV-specific cytotoxic T lymphocytes and other cell therapies can be safely and effectively transfused to prevent and treat some diseases caused by EBV. This review will mainly focus on discussing EBV-specific cytotoxic T lymphocytes and will touch on therapeutic EBV vaccines and chimeric antigen receptor T-cell therapy briefly. [ABSTRACT FROM AUTHOR]

Background: Our previous studies found that high-intensity focused ultrasound (HIFU) stimulated tumor-specific T cells in a mouse H22 tumor model, and adoptive transfer of the T cells from HIFU-treated mice could subsequently elicit stronger inhibition on the growth and progression of the implanted tumors. The aim of this study was to investigate the mechanism of T cells from focused ultrasound ablation in HIFU-mediated immunomodulation. Methods: Sixty H22 tumor-bearing mice were treated by either HIFU or sham- HIFU, and 30 naïve syngeneic mice served as controls. All mice were euthanized on day 14 after HIFU and splenic T cell suspensions were obtained in each group. Using an adoptive cell transfer model, a total of 1 × 106 T cells from HIFU treatedmice were intravenously injected into each syngeneic H22 tumor-bearing mouse twice on day 3 and 4, followed by the sacrifice for immunological assessments at 14 days after the adoptive transfer. Results: T cells from HIFU-treated mice could significantly enhance the cytotoxicity of CTLs (p < 0.001), with a significant increase of TNF-a (p < 0.001) and IFN-g secretion (p < 0.001). Compared to control and sham-HIFU groups, the number of Fas ligand+ and perforin+ tumor-infiltrating lymphocytes (TILs) and apoptotic H22 tumor cells were significantly higher (p < 0.001) in the HIFU group. There were linear correlations between apoptotic tumor cells and Fas ligand+ TILs (r = 0.9145, p < 0.001) and perforin+ TILs (r = 0.9619, p < 0.001). Conclusion: T cells from HIFU-treated mice can subsequently mediate cellular antitumor immunity, which may play an important role in the HIFU-based immunomodulation. [ABSTRACT FROM AUTHOR]

Background and Objectives: Inflammatory interstitial fibrosis and tubular atrophy (i-IFTA) is an inflammation in the area of tubular atrophy and fibrosis. i-IFTA is poorly associated with graft outcome and associated with infiltration of inflammatory mononuclear cells. A cytotoxic T cell is a granzyme B+CD8+CD3+ T cell, mainly secret granzyme B. Granzyme B is a serine protease that may mediate allograft injury and inflammatory interstitial fibrosis and tubular atrophy (i-IFTA). However, there is no report identifying the association of granzyme B with i-IFTA after a long post-transplant interval. Material and Methods: In this study, we have measured the cytotoxic T-cell frequency with flow cytometry, serum and PBMCs culture supernatants granzyme-B levels with ELISA and intragraft granzyme-B mRNA transcript expression with the RT-PCR in RTRs in 30 patients with biopsy-proven i-IFTA and 10 patients with stable graft function. Result: The frequency of cytotoxic T cells (CD3+CD8+ granzyme B+) in SGF vs. i-IFTA was (27.96 ± 4.86 vs. 23.19 ± 3.85%, p = 0.011), the serum granzyme-B level was (100.82 ± 22.41 vs. 130.32 ± 46.60, p = 0.038 pg/mL) and the intragraft granzyme-B mRNA transcript expression was (1.01 ± 0.048 vs. 2.10 ± 1.02, p < 0.001 fold). The frequency of CD3+ T cells in SGF vs. i-IFTA was (66.08 ± 6.8 vs. 65.18 ± 9.35%; p = 0.68) and that of CD3+CD8+ T cells was (37.29 ± 4.11 vs. 34.68 ± 5.43%; p = 0.28), which were similar between the 2 groups. CTLc frequency was negatively correlated with urine proteinuria (r = −0.51, p < 0.001), serum creatinine (r = −0.28, p = 0.007) and eGFR (r = −0.28, p = 0.037). Similarly, the PBMC culture supernatants granzyme-B level was negatively correlated with urine proteinuria (r = −0.37, p < 0.001) and serum creatinine (r = −0.31, p = 0.002), while the serum granzyme-B level (r = 0.343, p = 0.001) and intragraft granzyme-B mRNA transcript expression (r = 0.38, p < 0.001) were positively correlated with proteinuria. Conclusions: A decrease in the CTLc frequency in circulation and an increased serum granzyme-B level and intragraft granzyme-B mRNA expression shows that cytotoxic T cells may mediate the allograft injury in RTRs with i-IFTA by releasing granzyme B in serum and intragraft tissue. [ABSTRACT FROM AUTHOR]

The identification of novel biomarkers and therapeutic targets in advanced cancer is critical for improving cancer diagnosis and therapeutics. Survivin (SV) is highly expressed predominantly in most cancer cells and tissues but is absent or undetectable in terminally differentiated normal adult tissues. Therefore, it functions as an almost universal tumor antigen. Peptides are short chains of amino acids linked by peptide bonds. To obtain novel SV decamers that are able to induce SV-specific cytotoxic T lymphocytes (CTLs) with a higher cytotoxic efficiency against cancer cells, major histocompatibility complex (MHC) peptide binding algorithms were conducted to predict nine modified SV95 decamers (from SV95-2 to SV95-10) based on the natural SV95-104 peptide sequence of ELTLGEFLKL (here defined as SV95-1). The fluorescent density of each SV95 peptide was determined by a MHC stability assay, followed by the generation of SV95-specific CTLs with each SV95 peptide (from SV95-1 to SV95-10) and human dendritic cells (DCs) loaded with Poly(lactic-co-glycolic) acid (PLGA) nanoparticles encapsulated with SV95 peptide. Finally, IFN-γ ELISpot and CytoTox 96® Non-Radioactive Cytotoxicity Assays were employed to verify their cytotoxic efficiency of the SV95-specific CTLs generated with the corresponding artificial antigen presenting cells (aAPCs) containing SV95 (SV95-1 to SV95-10) peptide. Furthermore, the cytotoxicity of the SV95 specific CTLs generated with nine mutated SV95 peptides was compared to the one generated with natural SV95-1 peptide and TIL2080 cells. The results indicated that the HLA-A2-restricted mutated SV95 epitope decamers (SV95-6 and SV95-7) showed significant higher binding ability compared to natural peptide SV95-1 in MHC stability assay. More importantly, SV95-specific CTLs with higher cytotoxicity were successfully induced with both SV95-6 and SV95-7 peptides, which significantly eliminated target cells (not only SV95-1 peptide pulsed T2 cells, but also both HLA-A2 and SV positive cancer cells) when compared to those generated with natural SV95-1 peptide and TIL2080 cells. These findings suggest that the SV95-6 and SV95-7 peptides are two novel HLA-A2-restricted CTL epitopes and may be useful for the immunotherapy for patients with survivin expressing cancer.

Highlights Anti-cancer effects of hAEC depend on cancer type. Cross-reactive humoral responses do not mediate anti-cancer effects of hAEC. Anti-cancer effects of hAECs are mainly mediated by small-extracellular vesicles (sEV). hAEC-derived sEV (AD-sEV) trigger the Warburg’s effect leading to Arginine consumption and cancer cell apoptosis. AD-sEV substantially inhibits tumor development and increases survival and CTL responses.

Adoptive T-cell therapy (ACT) is successfully applied in cancer treatment; however, its efficiency can be limited by a low viability, short persistence time, and loss of functional activity of T-cells after adoptive transfer. The search for novel immunomodulators that can improve the viability, expansion, and functions of T-cells after their infusion with the minimal side effects could contribute to the development of more efficient and safe ACT strategies. Recombinant human cyclophilin A (rhCypA) is of particular interest in this respect, as it exhibits pleiotropic immunomodulatory activity and stimulates both innate and adaptive anti-tumor immunity. Here, we evaluated the effect of rhCypA on the efficacy of ACT in the mouse EL4 lymphoma model. Lymphocytes from transgenic 1D1a mice with an inborn pool of EL4-specific T-cells were used as a source of tumor-specific T-cells for ACT. In models of immunocompetent and immunodeficient transgenic mice, the course (3 days) rhCypA administration was shown to significantly stimulate EL4 rejection and prolong the overall survival of tumor-bearing mice after adoptive transfer of lowered doses of transgenic 1D1a cells. Our studies showed that rhCypA significantly improved the efficacy of ACT by enhancing the effector functions of tumor-specific cytotoxic T-cells. These findings open up the prospects for the development of innovative strategies of adoptive T-cell immunotherapy for cancer using rhCypA as an alternative to existing cytokine therapies. [ABSTRACT FROM AUTHOR]

Major diseases, such as cancer and COVID‐19, are frightening global health problems, and sustained action is necessary to develop vaccines. Here, for the first time, ethoxy acetalated dextran nanoparticles (Ace‐Dex‐NPs) are functionalized with 9‐N‐(4H‐thieno[3,2‐c]chromene‐2‐carbamoyl)‐Siaα2−3Galβ1−4GlcNAc (TCCSia‐LacNAc) targeting macrophages as a universal vaccine design platform. First, azide‐containing oxidized Ace‐Dex‐NPs are synthesized. After the NPs are conjugated with ovalbumin (OVA) and resiquimod (Rd), they are coupled to TCCSia‐LacNAc‐DBCO to produce TCCSia‐Ace‐Dex‐OVA‐Rd, which induce a potent, long‐lasting OVA‐specific cytotoxic T‐lymphocyte (CTL) response and high anti‐OVA IgG, providing mice with superior protection against tumors. Next, this strategy is exploited to develop vaccines against infection by severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2). The receptor‐binding domain (RBD) of the SARS‐CoV‐2 spike protein is the main target for neutralizing antibodies. The TCCSia‐Ace‐Dex platform is preferentially used for designing an RBD‐based vaccine. Strikingly, the synthetic TCCSia‐Ace‐Dex‐RBD‐Rd elicited potent RBD‐neutralizing antibodies against live SARS‐CoV‐2 infected Vero E6 cells. To develop a universal SARS‐CoV‐2 vaccine, the TCCSia‐Ace‐Dex‐N‐Rd vaccine carrying SARS‐CoV‐2 nucleocapsid protein (N) is also prepared, which is highly conserved among SARS‐CoV‐2 and its variants of concern (VOCs), including Omicron (BA.1 to BA.5); this vaccine can trigger strong N‐specific CTL responses against target cells infected with SARS‐CoV‐2 and its VOCs. [ABSTRACT FROM AUTHOR]

Purpose: Cisplatin-containing combination chemotherapy has been the standard of care since the late 1980s, but the response rate is <50%. Studies have shown that the efficiency of chemotherapy differs among molecular subtypes of bladder cancer. In this study, we aimed to correlate FOXA1, a marker for differentiation of the basal and luminal subtypes, with tumor immune cell infiltration and the effect of chemotherapy in bladder cancer. Materials and Methods: Eighty-three patients with bladder cancer treated with chemotherapy were reviewed. Clinicopathological variables for each case were recorded. FOXA1, M2 tumor-associated macrophage (TAM), dendritic cell (DC), and cytotoxic T lymphocyte (CTL) were examined by immunohistochemistry. The relationship between FOXA1, immune cell infiltration, and clinical response to chemotherapy was assessed. Results: The overall objective response rate was 34%. The objective response rate for tumors with lower FOXA1 expression was 58% and for tumors with higher FOXA1 expression was 12%. Tumors with infiltrated M2 TAM proportion <3% had a higher objective response rate compared with infiltrated M2 TAM proportion >3% tumors (46% vs. 21%, p = 0.02). Tumors with infiltrated CTL proportion >5% had a higher objective response rate compared with infiltrated CTL proportion <5% tumors (50% vs. 17%, p = 0.002). DCs showed no significant differences. We found that the objective response rate for tumors with lower FOXA1 expression, proportion <3% M2 TAM infiltration, and proportion >5% CTL infiltration is 82%. Lower FOXA1 expression was associated with low M2 TAM infiltration and high CTL infiltration. Conclusions: Thus, we showed that in patients with bladder cancer who received chemotherapy, the higher clinical response rate is associated with low FOXA1 expression, low M2 TAM infiltration, and high CTL infiltration. [ABSTRACT FROM AUTHOR]

Mesenchymal stromal/stem cells (MSCs) have been considered an attractive source of cytotherapy due to their promising effects on treating various diseases. Allogeneic MSCs (allo-MSCs) are extensively used in clinical trials due to their convenient preparation and credible performance. Traditionally, allo-MSCs are considered immunoprivileged with minimal immunogenicity and potent immunomodulatory capacity. However, growing evidence has suggested that allo-MSCs also induce immune response and cause rejection after transplantation, but the underlying cellular and molecular mechanisms remain to be elucidated. Here, we demonstrated that allografted MSCs upregulated MHC-II upon stimulation of IFN-γ in hepatic inflammatory environment by using mouse model of CCl4-induced liver injury. MHC-II upregulation enhanced the immunogenicity of allo-MSCs, leading to the activation of alloreactive T cells and rejection of allo-MSCs. However, MHC-II deficiency impaired the allogenic reactivity, thereby rescuing the loss of allo-MSCs. Mechanistically, CD4+ cytotoxic T lymphocytes (CTLs), rather than CD8+ CTLs, acted as the major effector for allo-MSC rejection. Under liver injury condition, the transplanted allo-MSCs upregulated CD80 and PD-L1, and CD8+ CTLs highly expressed CTLA-4 and PD-1, thereby inducing immune tolerance of CD8+ T cells to allo-MSCs. On the contrary, CD4+ CTLs minimally expressed CTLA-4 and PD-1; thus, they remain cytotoxic to allo-MSCs. Consequently, transplantation of MHC-II-deficient allo-MSCs substantially promoted their therapeutic effects in treating liver injury. This study revealed a novel mechanism of MSC allograft rejection mediated by CD4+ CTLs in injured liver, which provided new strategies for improving clinical performance of allo-MSCs in benefiting hepatic injury repair. [ABSTRACT FROM AUTHOR]

Although a high level of promiscuity for heterologous epitopes is believed to exist for cellular immunity, limited data explore this issue for human immunodeficiency virus type 1 (HIV-1)-specific CD8+ T lymphocyte (CTL) responses. Here, we found an unexpected degree of heterologous cross-reactivity against HIV-1 epitopes, in addition to the targeted index epitope. Most CTL clones screened cross-reacted against other known HIV-1 epitopes of the same major histocompatibility complex type I (MHC-I) restriction, up to 40% of tested nonindex epitopes in some cases. The observed cross-reactivity was universally lower avidity than recognition of the index epitope when examined for several A*02- and B*57-restricted CTL clones, demonstrating that the high concentrations of exogenous epitope typically used for screening of CTL responses are prone to detect such cross-reactivity spuriously. In agreement with this, we found that these cross-reactive responses do not appear to mediate CTL activity against HIV-1-infected cells. Overall, our data indicate that low-level cross-reactivity is remarkably common for HIV-1-specific CTLs. The role of this phenomenon is unclear, but low-avidity interactions have been shown to foster homeostatic proliferation of memory T cells.IMPORTANCE This study raises two issues related to HIV-1-specific CTL responses. These are key immune responses that retard disease progression in infected persons that are highly relevant to immunotherapies and vaccines for HIV-1. First, we make the novel observation that these responses are promiscuous and that CTLs targeting one epitope may cross-recognize other, completely distinct epitopes in the virus. While these are low-avidity interactions that do not appear to contribute directly to the antiviral activity of CTLs, this raises interesting biologic implications regarding the purpose of the phenomenon, such as providing a stimulus for these responses to persist long term. Second, the data raise a technical caveat to detection of CTL responses against particular epitopes, suggesting that some methodologies may unintentionally detect cross-reactivity and overestimate responses against an epitope.

The improved survival rate of ovarian cancer (OC) is related to the action of infiltrating cytotoxic T lymphocytes (CTLs). Recently, oncolytic adenoviruses (OAds) have emerged as a key player in treating solid tumors; however, the immunosuppressive tumor microenvironment (TME) and the body-mediated antiviral immune response limit their therapeutic effect. In this study, we tested the hypothesis that bispecific T-cell engagers (BiTEs) could activate and redirect CTLs to increase the anti-tumor effect of OAds. We modified the parental OAd to express a MUC16-targeting BiTE antibody (OAd-MUC16-BiTE), which retained its oncolytic properties and replication ability in vitro. This BiTE secreted from infected tumor cells into the microenvironment binds to MUC16 on target cells and cross‐links them to CD3 on T cells, leading to activation, proliferation, and toxicity of T cells against MUC16+ tumor cells. In cell coculture assays, OAd-MUC16-BiTE–mediated oncolysis enhanced T-cell–mediated tumor cell killing and bystander effect. In ex vivo tumor cultures freshly derived from OC patients, OAd-MUC16-BiTE overcame the suppressed immune TME, achieving stronger toxicity than the parental virus. Moreover, in the cell-derived xenograft and patient-derived xenograft model, OAd-MUC16-BiTE showed stronger antitumor activity and increased the number of CTLs, compared with the parental virus. Further, we demonstrated that the OAd-MUC16-BiTE-mediated anti-tumor activity is related to the reversal of the TME and improved MHC I antigen presentation. Overall, our results show how arming OAds with BiTE can overcome limitations in oncolytic virotherapy, yielding a potent therapy that is ready for clinical assessment.

We identified here mechanism by which hAECs exert their anti-cancer effects. We showed that vaccination with live hAEC conferred effective protection against murine colon cancer and melanoma but not against breast cancer in an orthotopic cancer cell inoculation model. hAEC induced strong cross-reactive antibody response to CT26 cells, but not against B16F10 and 4T1 cells. Neither heterotopic injection of tumor cells in AEC-vaccinated mice nor vaccination with hAEC lysate conferred protection against melanoma or colon cancer. Nano-sized AEC-derived small-extracellular vesicles (sEV) (AD-sEV) induced apoptosis in CT26 cells and inhibited their proliferation. Co-administration of AD-sEV with tumor cells substantially inhibited tumor development and increased CTL responses in vaccinated mice. AD-sEV triggered the Warburg’s effect leading to Arginine consumption and cancer cell apoptosis. Our results clearly showed that it is AD-sEV but not the cross-reactive immune responses against tumor cells that mediate inhibitory effects of hAEC on cancer development. Our results highlight the potential anti-cancer effects of extracellular vesicles derived from hAEC.Highlights: Anti-cancer effects of hAEC depend on cancer type. Cross-reactive humoral responses do not mediate anti-cancer effects of hAEC. Anti-cancer effects of hAECs are mainly mediated by small-extracellular vesicles (sEV). hAEC-derived sEV (AD-sEV) trigger the Warburg’s effect leading to Arginine consumption and cancer cell apoptosis. AD-sEV substantially inhibits tumor development and increases survival and CTL responses. [ABSTRACT FROM AUTHOR]

Aims: This study was conducted to explore the high-intensity focused ultrasound (HIFU) prepared antigen-sensitized dendritic cells (DC) and the induction of cytotoxic T lymphocyte (CTL) killing effects by DC and to observe their anti-tumor immunity effects on BALB/c mice.Methods and Material: GM-CSF and IL-4 were used to culture the mouse bone marrow-derived DC. HIFU was used to prepare CT-26 tumor cell antigen-sensitive DC vaccines. The capability of T cell proliferation was detected by 3H-TdR, and the CTL cytotoxicity was detected using standard 4h51Cr release assay. The DC-based tumor vaccine prepared using HIFU irradiation was given to normal BALB/c mice. The mice were injected with CT-26 cancer cells subcutaneously seven days later. Further, the occurrence time of the tumor, its weight and volume on the 20th day was observed, and the allergic DC group challenged using repeated-freezing-thawing method alone with the normal saline control group (negative control group) were used to compare group differences.Results: DC in the HIFU group, tumor cell freeze-thawing group, tumor supernatant group, and phosphate buffer solution (PBS) group could induce T cell proliferation in vitro. However, the ability to induce T cell proliferation of DC in the HIFU group and tumor cell freeze-thawing group was significantly higher than those in the tumor supernatant and PBS groups (P < 0. 05). CTL induced in vitro by DC in the HIFU group, and the tumor cell freeze-thawing group had significant cytotoxicity to colon cancer, being significantly different from those in the tumor supernatant and PBS groups (P < 0.05). There was no significant difference between the cytotoxicity of CTL induced in vitro in the HIFU group and the tumor cell freeze-thawing group (P > 0.05). Additionally, significant differences in the occurrence time of the tumor, its weight and volume on the 20th day, and the median survival time of mice among the HIFU group, the repeated-freezing-thawing group, and the negative control group were observed (P < 0.01 or P < 0.05). There was a significant difference between the HIFU and the repeated-freezing-thawing group (P < 0.05).Conclusions: HIFU prepared antigen-sensitized DC could cause substantial proliferation of T cells and CTL with strong anti-tumor effects. The DC-based tumor vaccine prepared using HIFU irradiation affected active immunization on the tumor occurrence in vitro and was better than the DC-based tumor vaccine prepared using the repeated-freezing-thawing method. [ABSTRACT FROM AUTHOR]

Background and Objectives: Inflammatory interstitial fibrosis and tubular atrophy (i-IFTA) is an inflammation in the area of tubular atrophy and fibrosis. i-IFTA is poorly associated with graft outcome and associated with infiltration of inflammatory mononuclear cells. A cytotoxic T cell is a granzyme B+CD8+CD3+ T cell, mainly secret granzyme B. Granzyme B is a serine protease that may mediate allograft injury and inflammatory interstitial fibrosis and tubular atrophy (i-IFTA). However, there is no report identifying the association of granzyme B with i-IFTA after a long post-transplant interval. Material and Methods: In this study, we have measured the cytotoxic T-cell frequency with flow cytometry, serum and PBMCs culture supernatants granzyme-B levels with ELISA and intragraft granzyme-B mRNA transcript expression with the RT-PCR in RTRs in 30 patients with biopsy-proven i-IFTA and 10 patients with stable graft function. Result: The frequency of cytotoxic T cells (CD3+CD8+ granzyme B+) in SGF vs. i-IFTA was (27.96 ± 4.86 vs. 23.19 ± 3.85%, p = 0.011), the serum granzyme-B level was (100.82 ± 22.41 vs. 130.32 ± 46.60, p = 0.038 pg/mL) and the intragraft granzyme-B mRNA transcript expression was (1.01 ± 0.048 vs. 2.10 ± 1.02, p < 0.001 fold). The frequency of CD3+ T cells in SGF vs. i-IFTA was (66.08 ± 6.8 vs. 65.18 ± 9.35%; p = 0.68) and that of CD3+CD8+ T cells was (37.29 ± 4.11 vs. 34.68 ± 5.43%; p = 0.28), which were similar between the 2 groups. CTLc frequency was negatively correlated with urine proteinuria (r = −0.51, p < 0.001), serum creatinine (r = −0.28, p = 0.007) and eGFR (r = −0.28, p = 0.037). Similarly, the PBMC culture supernatants granzyme-B level was negatively correlated with urine proteinuria (r = −0.37, p < 0.001) and serum creatinine (r = −0.31, p = 0.002), while the serum granzyme-B level (r = 0.343, p = 0.001) and intragraft granzyme-B mRNA transcript expression (r = 0.38, p < 0.001) were positively correlated with proteinuria. Conclusions: A decrease in the CTLc frequency in circulation and an increased serum granzyme-B level and intragraft granzyme-B mRNA expression shows that cytotoxic T cells may mediate the allograft injury in RTRs with i-IFTA by releasing granzyme B in serum and intragraft tissue.

Objective: The study evaluated the efficacy of combined epigenetic drugs of decitabine (DAC), valproic acid (VPA), and trichostatin A (TSA) on immunotherapy against glioma. Methods: The expression and prognosis of MAGE-D4 in glioma were analyzed online, and the expression of MAGE-D4 and HLA-A2 in glioma induced by epigenetic drugs was detected by qRT-PCR, Western blot, and flow cytometry. The methylation status of the MAGE-D4 promoter was determined by pyrosequencing. An HLA-A2 restricted MAGE-D4 peptide was predicted and synthesized. An affinity assay and a peptide/HLA complex stability assay were performed to determine the affinity between peptide and HLA. CCK8 assay, CFSE assay, ELISA and ELISPOT were performed to detect the function of MAGE-D4 peptide-specific T cells. Flow cytometry, ELISA, and cytotoxicity assays were used to detect the cytotoxicity effect of MAGE-D4 peptidespecific T cells combined with epigenetic drugs against glioma in vitro. Finally, the glioma-loaded mouse model was applied to test the inhibitory effect of specific T cells on gliomas in vivo. Results: MAGE-D4 was highly expressed in glioma and correlated with poor prognosis. Glioma cells could be induced to express MAGE-D4 and HLA-A2 by epigenetic drugs. MAGE-D4-associated peptides were found that induce DCs to stimulate the highest T-cell activities of proliferation, IL-2 excretion, and IFN-g secretion. MAGE-D4 peptide-specific T cells treated with TSA only or combining TSA and DAC had the most cytotoxicity effect, and its cytotoxicity effect on glioma cells decreased significantly after HLA blocking. In vivo experiments also confirmed that MAGE-D4-specific T cells inhibit TSA-treated glioma. Conclusion: MAGE-D4 is highly expressed in glioma and correlated with the prognosis of glioma. The novel MAGE-D4 peptide identified was capable of inducing MAGE-D4-specific T cells that can effectively inhibit glioma growth, and the epigenetic drug application can enhance this inhibition. [ABSTRACT FROM AUTHOR]

Background: Granzyme-B is a serine proteinase expressed and released mainly by the cytotoxic T and NK cell. Granules intact Granzyme-B is directly delivered into the target cell, while extracellular Granzyme-B, released in serum leads to nonspecific cleavages of extracellular matrix molecules like vitronectin, collagen, TGF-ß, IL-1 and invites systemic inflammation, tissue remodeling and fibrosis leading to the development of chronic renal allograft dysfunction. Objective: We aimed to immunophenotype the Granzyme-B positive T-lymphocyte subset and Granzyme-B role in the development of chronic renal allograft dysfunction. Methods: We have analyzed the Granzyme-B+CD8+T/CD8neg and Granzyme-B+CD3+/CD3neg cell subset by the flowcytometry and serum Granzyme-B level by the enzyme-linked immunosorbent assay. Results: We have found that the frequency of Granzyme-B+ CD8neg CD3+T cell, Granzyme-B+ CD8lowCD3+T cell and Granzyme-B+ CD8high CD3+T cell subset was significantly lower and serum Granzyme-B level was significantly higher in CAD group. The frequency of CD3+T, CD3neg lymphocyte, CD8neg CD3+T, CD8lowCD3+T, CD8high CD3+T, Granzyme-B+CD3negCD8neg lymphocyte was similar between the group. The frequency of CD3+CD8negGzm-B+ cell was negatively correlated with serum creatinine and CD3+CD8highGzm-B+ cell was negatively correlated with serum Granzyme-B level. Similarly, Serum Granzyme-B level was positively correlated with serum creatinine, urine proteinuria and negatively with eGFR. Conclusion: The circulating frequency of Granzyme-B+ CD8neg CD3+T cell, Granzyme-B+ CD8lowCD3+T cell and Granzyme-B+ CD8high CD3+T cell subsets were significantly lower and serum Granzyme-B level was significantly higher in renal allograft recipients with CAD. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is a malignant tumor with high mortality, but lacks effective treatments. Carcinoembryonic antigen glypican-3 (GPC3) is a tumor-associated antigen overexpressed in HCC but rarely expressed in healthy individuals and thus is one of the most promising therapeutic targets. T cell epitope-based vaccines may bring light to HCC patients, especially to the patients at a late stage. However, few epitopes from GPC3 were identified to date, which limited the application of GPC3-derived epitopes in immunotherapy and T cell function detection. In this study, a total of 25 HLA-A0201 restricted GPC3 epitopes were in silico predicted and selected as candidate epitopes. Then, HLA-A0201+/GPC3+ HCC patients' PBMCs were collected and co-stimulated with the candidate epitope peptides in ex vivo IFN-γ Elispot assay, by which five epitopes were identified as real-world epitopes. Their capacity to elicit specific CD8+ T cells activation and proliferation was further confirmed by in vitro co-cultures of patients' PBMCs with peptide, in vitro co-cultures of healthy donors' PBLs with DCs and peptide, T2 cell binding assay as well as HLA-A2 molecule stability assay. Moreover, the in vivo immunogenicity of the five validated epitopes was confirmed by peptides cocktail/poly(I:C) vaccination in HLA-A0201/DR1 transgenic mice. Robust epitope-specific CD8+ T cell responses and cytotoxicity targeting HepG2 cells were observed as detected by IFN-γ Elispot, intracellular IFN-γ staining and cytolysis assay. This study provided novel GPC3 CTL epitopes for the development of T cell epitope vaccines and evaluation of GPC3 specific T cell responses. [ABSTRACT FROM AUTHOR]

Nonresolving inflammation is involved in the initiation and progression process of tumorigenesis. Src homology 2 domain-containing tyrosine phosphatase 2 (SHP2) is known to inhibit acute inflammation but its role in chronic inflammation-associated cancer remains unclear. The role of SHP2 in T cells in dextran sulfate sodium (DSS)-induced colitis and azoxymethane-DSS-induced colitis-associated carcinogenesis was examined using SHP2CD4-/- conditional knockout mice. SHP2 deficiency in T cells aggravated colitis with increased level of pro-inflammatory cytokines including IFN-γ and IL-17A. In contrast, the SHP2CD4-/- mice developed much fewer and smaller tumors than wild type mice with higher level of IFN-γ and enhanced cytotoxicity of CD8+ T cells in the tumor and peritumoral areas. At the molecular level, STAT1 was hyper-phosphorylated in T cells lacking SHP2, which may account for the increased Th1 differentiation and IFN-γ secretion. IFN-γ neutralization or IFN-γ receptor knockout but not IL-17A neutralization, abrogated the anti-tumor effect of SHP2 knockout with lowered levels of perforin 1, FasL and granzyme B. Finally, the expression of granzyme B was negatively correlated with the malignancy of colon cancer in human patients. In conclusion, these findings suggest a new strategy to treat colitis-associated cancer via targeting SHP2.

Transforming growth factor β (TGFβ) is an important differentiation factor for cytotoxic T lymphocytes (CTLs) and alters the expression levels of several of homing receptors during infection. SMAD4 is part of the canonical signaling network used by members of the transforming growth factor family. For this study, genetically modified mice were used to determine how SMAD4 and TGFβ receptor II (TGFβRII) participate in transcriptional programming of pathogen-specific CTLs. We show that these molecules are essential components of opposing signaling mechanisms, and cooperatively regulate a collection of genes that determine whether specialized populations of pathogen-specific CTLs circulate around the body, or settle in peripheral tissues. TGFβ uses a canonical SMAD-dependent signaling pathway to downregulate Eomesodermin (EOMES), KLRG1, and CD62L, while CD103 is induced. Conversely, in vivo and in vitro data show that EOMES, KLRG1, CX3CR1, and CD62L are positively regulated via SMAD4, while CD103 and Hobit are downregulated. Intravascular staining also shows that signaling via SMAD4 promotes formation of long-lived terminally differentiated CTLs that localize in the vasculature. Our data show that inflammatory molecules play a key role in lineage determination of pathogen-specific CTLs, and use SMAD-dependent signaling to alter the expression levels of multiple homing receptors and transcription factors with known functions during memory formation.

Xiuxiu Lin,1 Anhui Xu,1 Li Zhou,1 Na Zhao,1 Xinhui Zhang,2 Jin Xu,3 Shanglong Feng,2 Changcheng Zheng1 1Department of Hematology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, People’s Republic of China; 2Department of Hematology, Anhui Provincial Hospital, Anhui Medical University, Hefei, People’s Republic of China; 3Wannan Medical College, Wuhu, People’s Republic of ChinaCorrespondence: Changcheng ZhengDepartment of Hematology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, People’s Republic of ChinaTel/ Fax +86-551-62284476Email zhengchch1123@ustc.edu.cnBackground: Primary immune thrombocytopenia (ITP) is defined as an acquired autoimmune disease characterized by isolated thrombocytopenia. This work is to further clarify the relationship between T cell immune dysfunction and the pathogenesis of ITP.Methods: 37 adult patients with ITP were selected and were classified into newly diagnosed ITP (nITP, n = 13), persistent ITP (pITP, n = 6) and chronic ITP (cITP n = 18). The frequency of cytotoxic T lymphocytes (Tc1, Tc2, and Tc17) and helper T cells (Th1, Th2, and Th17), Tregs, and the expression of chemokine receptors and PD-1 on CD4+ T cells were investigated by flow cytometry. Plasma levels of T cell-related cytokines (IL-2, IL-4, IL-6, IL-10, TNF-α, IFN-γ, IL-17) were measured by cytometric beads array (CBA).Results: The percentage of Tc1 in cITP was greatly higher than nITP and healthy controls (p < 0.05, p < 0.01). The percentage of Treg in nITP and cITP groups was remarkably lower than those in healthy control group (p < 0.05, p < 0.001); and according to platelet count analysis (PLT< 50x109/L or PLT> 50x109/L), Treg cells in ITP group were significantly lower than those in healthy control group (p < 0.001, p < 0.05). The percentage of CD4+CXCR3+ of cITP was significantly higher than healthy controls and nITP (p < 0.01, p < 0.05). The percentage of CD4+CCR6+ in cITP was significantly higher than healthy controls and nITP (p < 0.001, p < 0.05). The expression of PD-1 in cITP patients was higher than healthy control (p < 0.05), but there was no significant difference among nITP, pITP and cITP (p = 0.25). The levels of IL-2, IFN-γ and TNFα in nITP group and cITP group were significantly higher than those in healthy control group (p < 0.01, p < 0.05; p < 0.01, p < 0.05; p < 0.05, p < 0.05), and the level of IL-10 in nITP group was significantly higher than that in pITP group (p < 0.05).Conclusion: Our results suggest that T lymphocyte immune dysfunction does exist in adult ITP patients and plays an important role in the pathogenesis of ITP.Keywords: primary immune thrombocytopenia, T helper cells, cytotoxic T lymphocyte, regulatory T cells

We present the case of a patient with multiple tyrosine kinase inhibitor (TKI)-refractory chronic phase chronic myeloid leukemia (CP-CML) with a T315I mutation of abl1. Dasatinib, a second-generation TKI, was administered as the initial treatment but achieved neither a cytogenetic nor molecular response. A mutational analysis of abl1 revealed that the patient had a T315I mutation. The patient was then administered ponatinib, a third-generation TKI, which is thought to be effective against T315I; however, the complete blood counts became within normal limits, and neither a cytogenetic nor molecular response was achieved. However, the patient has maintained a healthy chronic phase (with no blast crises) for more than 5½ years since the diagnosis of CP-CML. T-cell receptor (TCR) repertoire analyses using peripheral blood revealed a remarkable clonal expansion of effector cytotoxic T lymphocytes (CTLs) that contained TCR V beta 13.6. We observed the clonal expansion of naïve CTLs with TCR V beta 13.6; however, no clonality was observed in the memory CTLs. The naïve and effector CTLs persisted at very high percentages since the seventh month after starting dasatinib. The CTLs could not have led to the molecular response; therefore, there might be plenty of CML stem cells remaining in the bone marrow. Therefore, although the CTLs might have prevented the disease from developing blast crises over more than 5 years, the CTLs might not have been able to become memory CTLs.

Determining the appropriate source of antigens for optimal antigen presentation to T cells is a major challenge in designing dendritic cell (DC) -based therapeutic strategies against hepatocellular carcinoma (HCC). Tumor-derived exosomes (Tex) express a wide range of tumor antigens, making them a promising source of antigens for DC vaccines. As reported, the exosomes secreted by tumor cells can inhibit the antitumor function of immune cells. In this study, we transfected hepatocellular carcinoma cells with Rab27a to enhance the yield of exosomes, which were characterized using transmission electron microscopy and Western blot analysis. We found that Tex secreted by overexpressing Rab27a Hepatocellular carcinoma cell lines pulsed DC is beneficial for the differentiation and maturation of DCs but inhibits the secretion of the IL-12 cytokine. Consequently, we developed a complementary immunotherapy approach by using Tex as an antigen loaded onto DCs, in combination with the cytokine IL-12 to induce antigen-specific cytotoxic T lymphocytes （CTLs）. The results indicated that the combination of DC-Tex and IL-12 was more effective in stimulating T lymphocyte proliferation, releasing IFN-γ， and enhancing cytotoxicity compared to using exosomes or IL-12 alone. Additionally, the inclusion of IL-12 also compensated for the reduced IL-2 secretion by DCs caused by Tex. Moreover, in a BALB/c nude mice model of hepatocellular carcinoma, CTLs induced by DC-Tex combined with IL-12 maximized the tumor-specific T-cell immune effect and suppressed tumor growth. Thus, Tex provides a novel and promising source of antigens, with cytokines compensating for the shortcomings of Tex as a tumor antigen. This work helps to clarify the role of exosomes in tumor immunotherapy and may offer a safe and effective prospective strategy for the clinical application of exosome-based cellular immunotherapy. [ABSTRACT FROM AUTHOR]

Vascular endothelial growth factor (VEGF) has important effects on hematopoietic and immune cells. A link between VEGF expression, tumor progression, and metastasis has been established in various solid tumors; however, the impact of VEGF expression by hematopoietic neoplasias remains unclear. Here, we investigated the role of VEGF in plasma cell neoplasia. Overexpression of VEGF in MOPC 315 tumor cells (MOPCSVm) had no effect on their growth in vitro. However, constitutive ectopic expression of VEGF dramatically reduced tumorigenicity of MOPC 315 when implanted subcutaneously into BALB/c mice. Mice implanted with MOPCSVm effectively rejected tumor grafts and showed strong cytotoxic T lymphocyte (CTL) activity against parental MOPC 315 cells. MOPCSVm implants were not rejected in nude mice, suggesting the process is T-cell-dependent. Adoptive transfer of splenocytes from recipients inoculated with MOPCSVm cells conferred immunity to naïve BALB/c mice, and mice surviving inoculation with MOPCSVm rejected the parental MOPC 315 tumor cells following a second inoculation. Immunohistochemical analysis showed that MOPCSVm induced a massive infiltration of CD3+ cells and MHC class II+ cells in vivo. In addition, exogenous VEGF induced the expression of CCR3 in T cells in vitro. Together, these data are the first to demonstrate that overexpression of VEGF in plasmacytoma inhibits tumor growth and enhances T-cell-mediated antitumor immune response. [ABSTRACT FROM AUTHOR]

Supplemental Digital Content is available in the text Objectives: To elucidate the efficacy of adjuvant vaccine monotherapy using 3 Human Leukocyte Antigen (HLA)-A∗24-restricted tumor-specific peptide antigens for ESCC, upregulated lung cancer 10, cell division cycle associated 1, and KH domain-containing protein overexpressed in cancer 1. Summary of Background Data: ESCC patients with pathologically positive nodes (pN(+)) have a high risk for postoperative recurrence, despite curative resection after preoperative therapy. Subclinical micrometastases are an appropriate target for cancer vaccine. Methods: This is a non-randomized prospective phase II clinical trial (UMIN000003557). ESCC patients curatively resected after preoperative therapy with pN(+) were allocated into the control and vaccine groups (CG and VG) according to the HLA-A status. One mg each of three epitope peptides was postoperatively injected 10 times weekly followed by 10 times biweekly to the VG. The primary and secondary endpoints were relapse-free survival (RFS) and esophageal cancer-specific survival (ECSS), respectively. Results: Thirty were in the CG and 33 in the VG. No significant difference was observed in RFS between the CG and VG (5-year RFS: 32.5% vs 45.3%), but the recurrence rate significantly decreased with the number of peptides which induced antigen-specific cytotoxic T lymphocytes. The VG showed a significantly higher 5-year ECSS than the CG (60.0% vs 32.4%, P = 0.045) and this difference was more prominent in patients with CD8+ and programmed death-ligand 1 double negative tumor (68.0% vs 17.7%, P = 0.010). Conclusions: Our cancer peptide vaccine might improve the survival of ESCC patients, which is warranted to be verified in the phase III randomized controlled study. [ABSTRACT FROM AUTHOR]

We present the case of a 78-year-old male patient who was diagnosed with anaplastic lymphoma kinase (ALK)-negative, CC chemokine receptor 4 (CCR4)-negative, and CD30-positive anaplastic large cell lymphoma (ALCL). The patient had a past medical history of adult T-cell leukemia/lymphoma and colon cancers that had developed simultaneously approximately 2 years prior to the development of ALCL that were treated with immunochemotherapy and resection, respectively. Initial treatment for ALCL included brentuximab vedotin, an anti-CD30 monoclonal antibody-monomethyl auristatin E conjugate; however, we were unable to achieve a sufficient treatment effect. Romidepsin, an oral histone deacetylase inhibitor, was introduced as salvage chemotherapy; complete remission was attained. Interestingly, a reversal of the CD4/CD8 ratio and a reduction in human T-lymphotropic virus type 1 (HTLV-1) virus load was observed after 2 cycles of immunochemotherapy; the patient experienced upregulation of HTLV-1 Tax-specific cytotoxic T lymphocytes after a herpes zoster infection and the completion of immunotherapy. The immunologic status was maintained from the time of diagnosis through the completion of romidepsin therapy. Our findings indicate that romidepsin can be used safely and effectively to treat ALCL without impairing cellular immunity to HTLV-1.

This case report is about a patient who suffered from Philadelphia chromosome (Ph1)-positive acute lymphoblastic leukemia. The blasts were positive for myeloid-lineage markers including CD13 and CD33, as well as B-cell-lineage markers. Minor bcr-abl1 mRNA was detected by real-time quantitative polymerase chain reaction. Chromosomal abnormality monosomy 7 was also observed, in addition to Ph1. Despite treatment difficulties that were anticipated based on these findings, the patient had long-time complete molecular response (CMR) for approximately 5 years using chemotherapy and two tyrosine kinase inhibitors, imatinib and dasatinib. Lymphocytes were elevated after the patient switched from imatinib to dasatinib, and a T-cell receptor (TCR) V beta gene repertoire analysis revealed oligoclonal expansion of effector and memory cytotoxic T lymphocytes (CTLs), including Wilms tumor 1-specific CTLs. More specifically, the two memory CTLs expressing TCR V beta 3 and V beta 7.1 gradually increased after dasatinib administration. The activation and maintenance of anti-leukemia immunity may have allowed the patient to obtain long-time CMR. These results highlight that obtaining memory CTLs for leukemia cells may lead to safe withdrawal from dasatinib in the patient.

Herein, we present the case of a patient who suffered from adult T-cell leukemia/lymphoma (ATLL) and hepatocellular carcinoma (HCC) after obtaining a sustained virological response following treatment with a direct-acting antiviral (DAA) at different points in time. The patient went into complete remission (CR) for ATLL. Unfortunately, subsequent relapse of ATLL was observed. This situation was overcome using chemotherapy with pegylated interferon alpha-2b. Human T lymphotropic virus type 1 Tax-specific cytotoxic T lymphocytes (CTLs) were recognized after obtaining second CR, and those CTLs have been maintained for many years. After 4 years from the second CR, chronic hepatitis type C was treated with a DAA, and sustained virological response was attained. However, the occurrence of HCC was detected. Surprisingly, the tumor disappeared spontaneously. Hepatitis virus type C-specific CTLs were also detected in the patient. T-cell receptor (TCR) V beta gene repertoire analyses revealed oligoclonal expansion of effector and memory CTLs. The number of CTLs expressing the TCR V beta 13.1 has increased over the years since HCC occurrence. The activation and maintenance of anticancer cellular immunity may have allowed the patient to obtain long-term survival and overcome two lethal neoplasms.

Abstract Background Prediction and identification of cytotoxic T lymphocyte (CTL) epitopes from tumor associated antigens is a crucial step for the development of tumor immunotherapy strategy. Endocan has been identified as antigen overexpressed in various tumors. Methods In this experiment, we predicted and identified HLA-A2-restricted CTL epitopes from endocan by using the following procedures. Firstly, we predicted the epitopes from the amino acid sequence of endocan by computer-based methods; Secondly, we determined the affinity of the predicted peptide with HLA-A2.1 molecule by peptide-binding assay; Thirdly, we elicited the primary T cell response against the predicted peptides in vitro; Lastly, we tested the specific CTLs toward endocan and HLA-A2.1 positive target cells. Results These data demonstrated that peptides of endocan containing residues 4–12 and 9–17 could elicit specific CTLs producing interferon-γ and cytotoxicity. Conclusions Therefore, our findings suggested that the predicted peptides were novel HLA-A2.1-restricted CTL epitopes, and might provide promising target for tumor immunotherapy.

Increased human T-cell leukemia virus type 1 (HTLV-1) proviral load (PVL) is a significant risk factor for HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). There is controversy surrounding whether HTLV-1-specific cytotoxic T lymphocytes (CTLs) are beneficial or harmful to HAM/TSP patients. Recently, HTLV-1 Tax 301-309 has been identified as an immunodominant epitope restricted to HLA-A*2402. We investigated whether HLA-A*24 reduces HTLV-1 PVL and the risk of HAM/TSP using blood samples from 152 HAM/TSP patients and 155 asymptomatic HTLV-1 carriers. The allele frequency of HLA-A*24 was higher in HAM/TSP patients than in asymptomatic HTLV-1 carriers (72.4% vs. 58.7%, odds ratio 1.84), and HLA-A*24-positive patients showed a 42% reduction in HTLV-1 PVL compared to negative patients. Furthermore, the PVL negatively correlated with the frequency of Tax 301-309-specific CTLs. These findings are opposite to the effects of HLA-A*02, which reduces HTLV-1 PVL and the risk of HAM/TSP. Therefore, we compared the functions of CTLs specific to Tax 11-19 or Tax 301-309, which are immunodominant epitopes restricted to HLA-A*0201 or HLA-A*2402, respectively. The maximum responses of these CTLs were not different in the production of IFN-γ and MIP-1β or in the expression of CD107a-a marker for the degranulation of cytotoxic molecules. However, Tax 301-309-specific CTLs demonstrated 50-fold higher T-cell avidity than Tax 11-19-specific CTLs, suggesting better antigen recognition at low expression levels of the antigens. These findings suggest that HLA-A*24, which induces sensitive HTLV-1-specific CTLs, increases the risk of HAM/TSP despite reducing HTLV-1 PVL.

Purpose: This study aimed to develop and validate a prognostic model for metastasis-free survival (MFS) based on genes that may functionally interact with cytotoxic T lymphocytes (CTLs) and M2 macrophages in patients with triple-negative breast cancer (TNBC) who underwent adjuvant radiotherapy. Methods: The transcriptional and phenotypic profiles of TNBC and other breast cancer subtypes were downloaded from gene expression omnibus (GEO). The abundance of infiltrated immune cells was evaluated through CIBERSORTx or MCP-counter. A weighted linear model, the score for MFS (SMFS), was developed using the least absolute shrinkage and selection operator (LASSO) in GSE58812 and validated in GSE2034 and GSE12276. The biological implication of the SMFS was explored by evaluating its associations with TNBC molecular subtypes and other radiosensitivity- or immune-related signatures. Results: A model consisting of the PCDH12/ELP3, PCDH12/MSRA, and FAM160B2/MSRA gene expression ratios with non-zero coefficients finally selected by LASSO was developed using GSE58812. In GSE2034 (treatment with adjuvant radiotherapy), the SMFS was significantly associated with MFS in TNBC patients (hazard ratio (HR) = 8.767, 95% confidence interval (CI) 1.856–41.408, P = 0.006) and, to a lesser extent, in non-TNBC patients (HR = 2.888, 95% CI 1.076–7.750, P = 0.035). However, the interaction of subtype (TNBC vs non-TNBC) and the SMFS tended to be significant (Pinteraction = 0.081). In contrast, the SMFS was not significantly associated with MFS in either TNBC patients (P = 0.499) or non-TNBC patients (P = 0.536) in GSE12276 (treatment without radiotherapy). Among the four TNBC molecular subtypes, the c1 and c4 subtypes exhibited higher CTL infiltration and lower SMFS values than the c2 and c3 subtypes. In addition, the SMFS was positively correlated with the abundance of endothelial cells (r = 0.413, P < 0.001). Conclusion: The proposed model has the potential to predict MFS in TNBC patients after adjuvant radiotherapy, and the SMFS may represent a measurement of tumor immune suppression. [ABSTRACT FROM AUTHOR]

Acute cellular rejection (ACR) is a common complication after lung transplantation, which is mainly caused by the immune response of T lymphocytes recognizing the major histocompatibility complex on the cellular surface of grafts. It is currently considered as the main pattern of acute rejection. ACR is not only a direct cause of death of recipients, but also a high-risk factor for chronic rejection after lung transplantation. Nevertheless, it is a challenging task to deliver the diagnosis and treatment of ACR following lung transplantation. In this article, new progresses on the risk factors, pathogenesis, diagnosis and treatment of ACR in lung transplant recipients were summarized, aiming to improve the diagnostic and treatment efficiency of ACR and prolong the survival of recipients. [ABSTRACT FROM AUTHOR]

Graft-versus-host disease (GVHD) is a physiological response of the graft to allogeneic hosts. However, the effector cells, affected organ(s), and cytokines in the GVHD remain controversially discussed, without having determined a particular cytotoxic activity of the graft against the host. After i.v. injection of C57BL/6 (H-2b) spleen cells into irradiated BDF1 (H-2b/d) mice, the hosts developed interferon-gamma (IFN-γ)-dependent bone marrow (BM) GVHD on days 5–17. When H-2DdKd transgenic H-2b lymphoma cells were i.p. inoculated into irradiated, H-2b splenocyte-transplanted H-2b/d mice, the infiltration of macrophages cytotoxic against H-2DdKd transgenic H-2b mouse skin epithelia (a GVHD activity) into the peritoneal cavity preceded several days the infiltration of interleukin (IL)-2-dependent cytotoxic T lymphocytes (CTLs) to achieve a graft-versus-leukemia (GVL) effect. In contrast, allogeneic BM transplanted alone into the irradiated mice did not induce GVHD for 44 days, whereas i.v. injection of graft anti-host macrophages or graft anti-host CTLs along with allogeneic BM, respectively, induced GVHD or promoted the GVL effect in the absence of GVHD. These results revealed that macrophage-induced GVHD and the CTL-mediated GVL effect were a set (Th1: IFN-γ/IL-2) response of the graft to allogeneic hosts and leukemia cells, respectively, and that graft T cell activation rather than inhibition skipped GVHD after BM transplantation. [ABSTRACT FROM AUTHOR]