Tumor-infiltrating monocytic myeloid-derived suppressor cells contribute to the development of an immunosuppressive tumor microenvironment in gastric cancer.

BACKGROUND: Gastric cancer (GC) is characterized by an immunosuppressive and treatment-resistant tumor immune microenvironment (TIME). Here, we investigated the roles of different immunosuppressive cell types in the development of the GC TIME. METHODS: Single-cell RNA sequencing (scRNA-seq) and multiplex immunostaining of samples from untreated or immune checkpoint inhibitor (ICI)-resistant GC patients were used to examine the correlation between certain immunosuppressive cells and the prognosis of GC patients. RESULTS: The results of the scRNA-seq analysis revealed that tumor-infiltrating monocytic myeloid-derived suppressor cells (TI-M-MDSCs) expressed higher levels of genes with immunosuppressive functions than other immunosuppressive cell types. Additionally, M-MDSCs in GC tissues expressed significantly higher levels of these markers than adjacent normal tissues. The M-MDSCs were most enriched in GC tissues relative to adjacent normal tissues. Among the immunosuppressive cell types assessed, the M-MDSCs were most enriched in GC tissues relative to adjacent normal tissues; moreover, their presence was most strongly associated with a poor prognosis. Immediate early response 3 (IER3), which we identified as a differentially expressed gene between M-MDSCs of GC and adjacent normal tissues, was an independent poor prognostic factor in GC patients (P = 0.0003). IER3+ M-MDSCs expressed higher levels of genes with immunosuppressive functions than IER3- M-MDSCs and were abundant in treatment-resistant GC patients. CONCLUSIONS: The present study suggests that TI-M-MDSCs, especially IER3+ ones, may play a predominant role in the development of the immunosuppressive and ICI-resistant GC TIME.

Tertiary lymphoid structures correlate with enhancement of antitumor immunity in esophageal squamous cell carcinoma.

BACKGROUND: Tertiary lymphoid structures (TLSs) are associated with a favorable prognosis in several cancers. However, the correlation between TLSs and outcomes of esophageal squamous cell carcinoma (ESCC) and the impact of TLSs on the tumor immune microenvironment (TIME) remain unknown. METHODS: We pathologically evaluated the significance of TLSs in ESCC focusing on TLS maturation using 180 ESCC specimens and performed single-cell RNA sequencing (scRNA-seq) using 14 ESCC tissues to investigate functional differences of immune cells according to TLS presence. RESULTS: TLS+ cases had better recurrence-free-survival (RFS) (p < 0.0001) and overall survival (OS) (p = 0.0016) compared with TLS- cases. Additionally, mature TLS+ cases had better RFS and OS compared with immature TLS+ cases (p = 0.019 and p = 0.015) and TLS- cases (p < 0.0001 and p = 0.0002). The scRNA-seq showed that CD8+ T cells in TLS+ tumors expressed high levels of cytotoxic signatures and antigen-presentation of dendritic cells (DCs) was enhanced in TLS+ tumors. Immunohistochemistry showed that the densities of tumor-infiltrating CD8+ T cells and DCs were significantly higher in TLS+ tumors than those in TLS- tumors. CONCLUSIONS: These data suggest the prognostic and functional significance of TLSs in ESCC and provides new insights into TLSs on the TIME.

Contribution of pre-existing neoantigen-specific T cells to a durable complete response after tumor-pulsed dendritic cell vaccine plus nivolumab therapy in a patient with metastatic salivary duct carcinoma.

Although immune checkpoint inhibitors (ICIs) have emerged as new therapeutic options for refractory cancer, they are only effective in select patients. Tumor antigen-pulsed dendritic cell (DC) vaccine therapy activates tumor-specific cytotoxic T lymphocytes, making it an important immunotherapeutic strategy. Salivary ductal carcinoma (SDC) carries a poor prognosis, including poor long-term survival after metastasis or recurrence. In this study, we reported a case of refractory metastatic SDC that was treated with a tumor lysate-pulsed DC vaccine followed by a single injection of low-dose nivolumab, and a durable complete response was achieved. We retrospectively analyzed the immunological factors that contributed to these long-lasting clinical effects. First, we performed neoantigen analysis using resected metastatic tumor specimens obtained before treatment. We found that the tumor had 256 non-synonymous mutations and 669 class I high-affinity binding neoantigen peptides. Using synthetic neoantigen peptides and ELISpot analysis, we found that peripheral blood mononuclear leukocytes cryopreserved before treatment contained pre-existing neoantigen-specific T cells, and the cells obtained after treatment exhibited greater reactivity to neoantigens than those obtained before treatment. Our results collectively suggest that the rapid and long-lasting effect of this combination therapy in our patient may have resulted from the presence of pre-existing neoantigen-specific T cells and stimulation and expansion of those cells following tumor lysate-pulsed DC vaccine and ICI therapy.

Intranodal Administration of Neoantigen Peptide-loaded Dendritic Cell Vaccine Elicits Epitope-specific T Cell Responses and Clinical Effects in a Patient with Chemorefractory Ovarian Cancer with Malignant Ascites.

Chemorefractory ovarian cancer has limited therapeutic options. Hence, new types of treatment including neoantigen-specific immunotherapy need to be investigated. Neoantigens represent promising targets for personalized cancer immunotherapy. We here describe the clinical and immunological effects of a neoantigen peptide-loaded DC-based immunotherapy in a patient with recurrent and chemoresistant ovarian cancer. A 71-year-old female patient with chemorefractory ovarian cancer and malignant ascites received intranodal vaccination of DCs loaded with four neoantigen peptides that were predicted by our immunogenomic pipeline. Following four rounds of vaccinations with this therapy, CA-125 levels were remarkably declined and tumor cells in the ascites were also decreased. Concordantly, the tumor-related symptoms such as respiratory discomfort improved without any adverse reactions. The reactivity against one HLA-A2402-restricted neoantigen peptide derived from a mutated PPM1 F protein was detected in lymphocytes from peripheral blood by IFN-γ ELISPOT assay. Furthermore, the neoantigen (PPM1 F mutant)-specific TCRs were detected in the tumor-infiltrating T lymphocytes post-vaccination. Our results showed that vaccination with intranodal injection of neoantigen peptide-loaded DCs may have clinical and immunological impacts on cancer treatment.

PTPN3 expressed in activated T lymphocytes is a candidate for a non-antibody-type immune checkpoint inhibitor.

It has been shown that protein tyrosine phosphatase non-receptor type (PTPN) 3 inhibits T-cell activation. However, there is no definitive conclusion about how the inhibition of PTPN3 in lymphocytes affects immune functions in human lymphocytes. In the present study, we showed that PTPN3 inhibition significantly contributes to the enhanced activation of activated human lymphocytes. The PTPN3 expression of lymphocytes was significantly increased through the activation process using IL-2 and anti-CD3 mAb. Interestingly, inhibiting the PTPN3 expression in activated lymphocytes significantly augmented the proliferation, migration, and cytotoxicity through the phosphorylation of zeta-chain-associated protein kinase 70 (ZAP-70), lymphocyte-specific protein tyrosine kinase (LCK), and extracellular signal-regulated kinases (ERK). Lymphocyte activation by PTPN3 inhibition was observed only in activated CD3+ T cells and not in NK cells or resting T cells. In therapy experiments using autologous tumors and lymphocytes, PTPN3 inhibition significantly augmented the number of tumor-infiltrated lymphocytes and the cytotoxicity of activated lymphocytes. Our results strongly imply that PTPN3 acts as an immune checkpoint in activated lymphocytes and that PTPN3 inhibitor may be a new non-antibody-type immune checkpoint inhibitor for cancer therapy.

[Development of Holistic Cancer Treatment Centering Cancer Patients - From the Standpoint of Hypoxia and Hedgehog Signaling].

Recently, hypoxia that is one of cancer microenvironments, takes much attention. Because circumstance that we usually perform experiment is 20% O2 condition, it is likely that different signaling pathways may be activated in vivo cancer. We focused Hedgehog(Hh)signaling as one of activated pathways under hypoxia. It has been shown that Hh signaling is activated under hypoxia, followed by inducing malignant phenotypes in pancreatic cancer. Therefore, Hh signaling inhibitor should elicit anti-tumor effect. However, if we consider "whole-person therapy" we should confirm how Hh signaling affects the function of immune cells. In the present study, we describe hypoxia/Hh signaling/functions of cancer cells and immune cells focusing our previous results.

Hedgehog signaling regulates PDL-1 expression in cancer cells to induce anti-tumor activity by activated lymphocytes.

We investigated whether hypoxia-induced activation of Hh signaling contributes to PDL-1 expression in cancer and whether it affects the anti-tumor function of activated lymphocytes. Hypoxia augmented PDL-1 expression and inhibition of Hh signaling reduced PDL-1 expression under hypoxia. When activated lymphocytes were cocultured with cancers treated with a Hh inhibitor, activated lymphocyte cell numbers increased under hypoxia. In contrast, this increase was abrogated when cancer cells were treated with a PDL-1 neutralizing antibody. These results suggest that Hh signaling is one of regulatory pathways of PDL-1 expression under hypoxia and that inhibiting Hh signaling may induce lymphocyte anti-tumor activity.

Inhibition of PTPN3 Expressed in Activated Lymphocytes Enhances the Antitumor Effects of Anti-PD-1 Therapy in Head and Neck Cancer, Especially in Hypoxic Environments.

In the tumor microenvironment, wherein cytotoxic lymphocytes interact with cancer cells, lymphocyte exhaustion, an immune checkpoint inhibitor target, is promoted. However, the efficacy of these inhibitors is limited, and improving response rates remains challenging. We previously reported that protein tyrosine phosphatase nonreceptor type (PTPN) 3 is a potential immune checkpoint molecule for activated lymphocytes and that PTPN3 inhibition should be a focus area for cancer immunotherapy development. Therefore, in this study, we focused on PTPN3-suppressive therapy in terms of lymphocyte exhaustion under hypoxic conditions, which are a cancer microenvironment, and investigated measures for improving the response to anti-programmed death receptor (PD)-1 antibody drugs. We found that PTPN3 expression was upregulated in activated lymphocytes under hypoxic conditions, similar to the findings for other immune checkpoint molecules, such as PD-1, T cell immunoglobulin mucin-3, and lymphocyte-activation gene-3; furthermore, it functioned as a lymphocyte exhaustion marker. In addition, PTPN3-suppressed activated lymphocytes promoted the mammalian target of rapamycin (mTOR)-Akt signaling pathway activation and enhanced proliferation, migration, and cytotoxic activities under hypoxic conditions. Furthermore, PTPN3 suppression in activated lymphocytes increased PD-1 expression and enhanced the antitumor effects of anti-PD-1 antibody drugs against head and neck cancer in vitro and in vivo. These results suggest that the suppression of PTPN3 expression in activated lymphocytes enhances the therapeutic effect of anti-PD-1 antibody drugs in head and neck cancer, especially under hypoxic conditions that cause lymphocyte exhaustion.

Blockade of histamine receptor H1 augments immune checkpoint therapy by enhancing MHC-I expression in pancreatic cancer cells.

BACKGROUND: Although immune checkpoint blockade (ICB) therapy has proven to be extremely effective at managing certain cancers, its efficacy in treating pancreatic ductal adenocarcinoma (PDAC) has been limited. Therefore, enhancing the effect of ICB could improve the prognosis of PDAC. In this study, we focused on the histamine receptor H1 (HRH1) and investigated its impact on ICB therapy for PDAC. METHODS: We assessed HRH1 expression in pancreatic cancer cell (PCC) specimens from PDAC patients through public data analysis and immunohistochemical (IHC) staining. The impact of HRH1 in PCCs was evaluated using HRH1 antagonists and small hairpin RNA (shRNA). Techniques including Western blot, flow cytometry, quantitative reverse transcription polymerase chain reaction (RT-PCR), and microarray analyses were performed to identify the relationships between HRH1 and major histocompatibility complex class I (MHC-I) expression in cancer cells. We combined HRH1 antagonism or knockdown with anti-programmed death receptor 1 (αPD-1) therapy in orthotopic models, employing IHC, immunofluorescence, and hematoxylin and eosin staining for assessment. RESULTS: HRH1 expression in cancer cells was negatively correlated with HLA-ABC expression, CD8+ T cells, and cytotoxic CD8+ T cells. Our findings indicate that HRH1 blockade upregulates MHC-I expression in PCCs via cholesterol biosynthesis signaling. In the orthotopic model, the combined inhibition of HRH1 and αPD-1 blockade enhanced cytotoxic CD8+ T cell penetration and efficacy, overcoming resistance to ICB therapy. CONCLUSIONS: HRH1 plays an immunosuppressive role in cancer cells. Consequently, HRH1 intervention may be a promising method to amplify the responsiveness of PDAC to immunotherapy.

Intratumoral FOXP3+VEGFR2+ regulatory T cells are predictive markers for recurrence and survival in patients with colorectal cancer.

Previously, we have shown that CD8(+)T/FOXP3(+) cell ratio but not FOXP3(+) cell number alone is an independent prognostic factor for colorectal cancer. In the present study, we evaluated whether the number of intratumoral FOXP3(+)VEGFR2(+) (itFOXP3(+)VEGFR2(+)) T cells alone could be a predictive factor for survival prognosis in patients with colorectal cancer. Distribution of regulatory T cells (Tregs) at tumor sites derived from 88 patients with primary colorectal cancer was fluorescence-immunohistochemically examined. Relatively low number of itFOXP3(+)VEGFR2(+) cells significantly correlated with better [corrected] disease-free survival (DS) and overall survival (OS); multivariate analysis indicated that number of itFOXP3(+)VEGFR2(+) cells is an independent predictive and prognostic factor of DS and OS while neither intratumoral FOXP3(+) cell number nor intratumoral FOXP3(+)VEGFR2(-) cell number alone showed significant correlation with DS or OS. These results suggest that FOXP3(+)VEGFR2(+) may be a better predictive Treg marker than FOXP3(+) alone for recurrence and survival in patients with colorectal cancer.

The Hedgehog inhibitor suppresses the function of monocyte-derived dendritic cells from patients with advanced cancer under hypoxia.

Immunotherapy using monocyte derived dendritic cells (Mo-DCs) from cancer patients has been developed; however, the Mo-DCs regularly studied have been derived from non-cancer bearing donors or mice, and evaluated in normoxic conditions. In the present study, we investigated the effects of Hedgehog (Hh) inhibitors which are being developed as molecular target drugs for cancer on the functions of Mo-DCs derived from patients with advanced cancer when cultured in a tumor-like hypoxic environment. Mo-DC induction, migration, chemotaxis, phagocytosis, maturation, IL-12 p40 or p70 secretion and the allogeneic lymphocyte stimulation activity of Mo-DCs from patients with advanced cancer were all significantly inhibited by the Hh inhibitor, cyclopamine under hypoxic conditions. Our results suggest that Hh signaling plays an important role in the maintenance and function of Mo-DCs derived from patients with advanced cancer when cultured under hypoxic conditions.

The Hedgehog inhibitor cyclopamine impairs the benefits of immunotherapy with activated T and NK lymphocytes derived from patients with advanced cancer.

Hedgehog (Hh) signaling is activated in various types of cancer and contributes to the progression, proliferation, and invasiveness of cancer cells. Many Hh inhibitors are undergoing clinical trial and show promise as anticancer drugs. Hh signaling is also induced in the activated T and NK (TNK) lymphocytes that are used in immunotherapy. Activated TNK lymphocyte therapy is anticipated to work well within a tumor's hypoxic environment. However, most studies on the immunobiological functions of activated TNK lymphocytes have been conducted on healthy donor samples, under normoxic conditions. In the present study, we evaluated the effects of Hh inhibition and oxygen concentrations on the function of activated TNK lymphocytes derived from patients with advanced cancer. Proliferation, migration, surface NKG2D expression, and cytotoxicity were all significantly inhibited, and IFN-γ secretion was significantly increased upon Hh inhibitor treatment of activated TNK lymphocytes under hypoxic conditions in vitro. Tumors from mice injected with cyclopamine-treated activated TNK lymphocytes showed a significant increase in tumor size and had fewer apoptotic cells compared with the tumors in mice injected with control activated TNK lymphocytes. These results suggest that Hh signaling plays a pivotal role in activated TNK lymphocyte cell function. Combination therapy using Hh inhibitors and activated TNK lymphocytes derived from patients with advanced cancer may not be advantageous.

PTPN3 inhibition contributes to the activation of the dendritic cell function to be a promising new immunotherapy target.

PURPOSE: In a previous study, protein tyrosine phosphatase non-receptor type (PTPN) 3 was identified as an immune checkpoint molecule in lymphocytes, and its potential as a novel target for cancer immunotherapy was anticipated. However, evaluation of dendritic cell (DC) function as antigen-presenting cells is critical for the development of immunotherapy. In this study, we aimed to analyze the biological effect of PTPN3 on DCs induced from human peripheral blood monocytes obtained from healthy individuals. METHODS: We used short-interfering RNA to knock down PTP3 in DCs. For DC maturation, we added cancer cell lysate and tumor necrosis factor-α/interferon-α to immature DCs. In the cytotoxic assay, the target cancer cells were SBC5, unmatched with DCs from healthy human leukocyte antigen (HLA)-A24, or Sq-1, matched with DCs. Enzyme-linked immunosorbent assay was used to determine the amount of cytokines. To examine the intracellular signaling system, intracellular staining was used. RESULTS: PTPN3 knockdown significantly increased the number of DCs, expression of CD80 and chemokine receptor (CCR)7, and production of interleukin-12p40/p70 in mature DCs. In the HLA-A24-restricted DC and human lung squamous cell carcinoma cell cytotoxic assay, inhibition of PTPN3 expression in mature DCs induced cytotoxic T lymphocytes with increased production of INF-γ and granzyme B, and enhanced toxicity against cancer cells and migration to cancer. Furthermore, inhibition of PTPN3 expression activated the mitogen-activated protein kinase pathway in DCs. CONCLUSION: Based on our findings, inhibition of PTPN3 expression could contribute to the development of novel cancer immunotherapies that activate not only lymphocytes but also DCs.

Immunological analysis of hybrid neoantigen peptide encompassing class I/II neoepitope-pulsed dendritic cell vaccine.

Neoantigens/ are tumor-specific antigens that evade central immune tolerance mechanisms in the thymus. Long-term tumor-specific cytotoxic T lymphocyte activity maintenance requires class II antigen-reactive CD4+ T cells. We had previously shown that intranodal vaccination with class I neoantigen peptide-pulsed dendritic cells (DCs) induced a robust immune response in a subset of patients with metastatic cancer. The present study aimed to perform a detailed ex vivo analysis of immune responses in four patients receiving an intranodal hybrid human leukocyte antigen class II neoantigen peptide encompassing a class I neoantigen epitope (hybrid neoantigen)-pulsed DC vaccine. After vaccination, strong T-cell reactions against the hybrid class II peptide and the class I-binding neoantigen peptide were observed in all four patients. We found that hybrid class II neoantigen peptide-pulsed DCs stimulated CD4+ T cells via direct antigen presentation and CD8+ T cells via cross-presentation. Further, we demonstrated that hybrid class II peptides encompassing multiple class I neoantigen epitope-pulsed DCs could present multiple class I peptides to CD8+ T cells via cross-presentation. Our findings provide insight into the mechanisms underlying hybrid neoantigen-pulsed DC vaccine therapy and suggest future neoantigen vaccine design.

Neoadjuvant chemotherapy enhances anti-tumor immune response of tumor microenvironment in human esophageal squamous cell carcinoma.

Although chemotherapy has been an essential treatment for cancer, the development of immune checkpoint blockade therapy was revolutionary, and a comprehensive understanding of the immunological tumor microenvironment (TME) has become crucial. Here, we investigated the impact of neoadjuvant chemotherapy (NAC) on immune cells in the TME of human esophageal squamous cell carcinoma using single cell RNA-sequencing. Analysis of 30 fresh samples revealed that CD8+/CD4+ T cells, dendritic cells (DCs), and macrophages in the TME of human esophageal squamous cell carcinoma showed higher levels of an anti-tumor immune response in the NAC(+) group than in the NAC(-) group. Furthermore, the immune cells of the NAC(+) group interacted with each other resulting in enhanced anti-tumor immune response via various cytokines, including IFNG in CD8+/CD4+ T cells, EBI3 in DCs, and NAMPT in macrophages. Our results suggest that NAC potentially enhances the anti-tumor immune response of immune cells in the TME.

Single-cell transcriptome analysis reveals functional changes in tumour-infiltrating B lymphocytes after chemotherapy in oesophageal squamous cell carcinoma.

BACKGROUND: Tumour immune microenvironment is related with carcinogenesis and efficacy of immunotherapy. B cells play major roles in humoral immunity, but detailed functions of tumour-infiltrating B lymphocytes (TIL-Bs) are unknown. Therefore, our aim was to investigate the functional heterogeneity of TIL-Bs in oesophageal squamous cell carcinoma (ESCC) and lymph nodes (LNs) during chemotherapy. METHODS: Single-cell transcriptome analysis was performed on 23 specimens. We also performed immunohistochemical analysis of immunoglobulin κ C (IGKC), an antibody-secreting cell (ASC) marker, in 166 ESCC samples and evaluated the implication of IGKC in 2-year recurrence free survival (RFS) and 3-year overall survival (OS). RESULTS: A total of 81,246 cells were grouped into 24 clusters. We extracted B cell clusters based on canonical markers and identified 12 TIL-B subtypes in ESCC. We found that several functions, such as co-stimulation and CD40 signalling, were enhanced in TIL-Bs after chemotherapy. The proportion of naive B cells (NBCs) decreased and B cell activation genes were up-regulated in NBCs after chemotherapy. The proportion of ASCs in tumours increased with the loss of migratory abilities and antibody production in ASCs was promoted after chemotherapy. Differentially expressed genes up-regulated with chemotherapy in ASCs correlated with prolonged survival with oesophageal cancer (p = .028). In a metastatic LN, the ASC proportion increased and B cell differentiation was enhanced. In immunohistochemical analysis, RFS and OS of high IGKC expression cases were significantly better than those of low IGKC expression cases (RFS: p < .0001, OS: p < .0001). And in multivariable analysis, the expression of IGKC was an independent favourable prognostic factor for RFS (hazard ratio (HR): 0.23, 95% confidence interval (CI): 0.12-0.45, p < .0001) and OS (HR: 0.20, 95% CI: 0.086-0.47, p = .0002) in ESCC. CONCLUSIONS: Our findings provide novel insights for the heterogeneity of TIL-Bs during chemotherapy and will be useful to understand the clinical importance of TIL-Bs.

Inclusive estimation of complex antigen presentation functions of monocyte-derived dendritic cells differentiated under normoxia and hypoxia conditions.

Dendritic cells (DCs) generated from monocytes under 20% O2 are now used as therapeutic tools for cancer patients. However, the O2 concentration is between 3 and 0.5% in most tissues. We evaluated these complicated functions of DCs under oxygen tensions mimicking in vivo situations. Immature DCs (imDCs) were generated from monocytes using IL-4 and GM-CSF under normoxia (20% O2; N-imDCs) or hypoxia (1% O2; H-imDCs). Mature DCs (mDCs) were induced with LPS. DCs were further exposed to normoxia (N/N-DCs) or hypoxia (N/H-DCs and H/H-DCs) conditions. Using a 2-D culture system, H-DCs were smaller in size than N-DCs, and H/H-DCs exhibited higher allo-T cell stimulation ability than N/N-DCs and N/H-DCs. On the other hand, motility and phagocytic ability of H/H-DCs were significantly lower than those of N/H-DCs and N/N-DCs. In a 3-D culture system, however, maturation of H/H-imDCs and N/H-imDCs was suppressed compared with N/N-imDCs as a result of their decreased motility and phagocytosis. Interestingly, silencing of HIF-1α by RNA interference decreased CD83 expression without affecting any antigen presentation abilities except for the ability to stimulate the allo-T cell population. Our data could help our understanding of DCs, especially therapeutic DCs, in vivo.

Two-dimensional single-shot tomography using a virtually imaged phased array and a spatial phase modulator.

A virtually imaged phased array (VIPA) installed optical interferometer has been expanded to the two-dimensional (2D) tomography from the previous one-dimensional single-shot imaging technique with keeping the resolution and the measurement range. A single-shot measurement has been realized by a spatial phase modulator installed in the optical interferometer and tracing the delay time to pixel numbers on a 2D charge-coupled device (CCD) image sensor. The flexibility of the sample position was experimentally confirmed to be >25 mm, in relation to the VIPA coherency, for which the number of the interference order was confirmed to be 35. As a demonstration, a surface profile of stacked gauge blocks was observed. The repeatability of the surface position was 5 µm for the surface profilometry. In addition, a multilayer structure was observed using a glass plate. The experimental resolution was 53 µm when the amplified spontaneous emission light generated by the optical fiber amplifier was used for the light source. The single-shot measurement was confirmed by the 2D-CCD at a frame rate of 30 frames per second (FPS), and it provided evidence that the 2D scanless profilometry was successfully achieved using the VIPA optical device.

Lymph Nodes as Anti-Tumor Immunotherapeutic Tools: Intranodal-Tumor-Specific Antigen-Pulsed Dendritic Cell Vaccine Immunotherapy.

Hundreds of lymph nodes (LNs) are scattered throughout the body. Although each LN is small, it represents a complete immune organ that contains almost all types of immunocompetent and stromal cells functioning as scaffolds. In this review, we highlight the importance of LNs in cancer immunotherapy. First, we review recent reports on structural and functional properties of LNs as sites for antitumor immunity and discuss their therapeutic utility in tumor immunotherapy. Second, we discuss the rationale and background of ultrasound (US)-guided intranodal injection methods. In addition, we review intranodal administration therapy of tumor-specific-antigen-pulsed matured dendritic cells (DCs), including neoantigen-pulsed vaccines.

VEGFR2 is selectively expressed by FOXP3high CD4+ Treg.

CD25+ FOXP3+CD4+ T cells (Treg) have been considered to play an important role in immune tolerance against several tumor antigens. It has also been indicated that high-level expression of FOXP3 (FOXP3high) is sufficient to confer suppressive activity to normal non-Treg. Here, we showed for the first time that vascular endothelial growth factor receptor 2 (VEGFR2) is selectively expressed by FOXP3high but not FOXP3low Treg. Such VEGFR2+ Treg exist in several tissues including PBMC and malignant effusion-derived lymphocytes. In conclusion, VEGFR2 may be a novel target for controlling Treg with highly suppressive function.