Cells In Tertiary Lymphoid Structures Research Articles

Abstract 6433: Anti-CD36 monoclonal antibody can sensitize the neoadjuvant chemotherapy response in PDAC by eliminating the senescent tertiary lymphatic structure

Abstract Objective: Pancreatic ductal adenocarcinoma (PDAC) is deadly and aggressive. Neoadjuvant chemotherapy (NAC) may reduce tumor volume and alter the resectability of the tumor. The efficacy of neoadjuvant chemotherapy in patients is still limited. Tertiary lymphoid structures (TLSs) develop in peripheral non-lymphoid tissues and are essential for the immune response and correlate with chemotherapy in various tumor types. However, more research is needed to determine how TLSs affect neoadjuvant chemotherapy in PDAC. We aim to determine how neoadjuvant chemotherapy affects tumor-infiltrating lymphocytes (TLSs) in PDAC patients. We also want to find a biomarker to boost PDAC neoadjuvant chemotherapy response. Methods: We retrospectively collected formalin-fixed paraffin embedded (FFPE) tissues from 115 PDAC patients without preoperative treatment and 72 patients pretreated with neoadjuvant chemotherapy. Multispectral images were processed using AI-powered image analysis software (Tissue Gnostics; Zeiss, Germany). The 10X Genomics platform was used to sequence single cells in tissue samples from five patients who received neoadjuvant chemotherapy (NAC) and five patients who had not received any treatment before analysis (pretreatment naïve, PN). TLS was separated using Laser Microdissection. The mouse model was created by orthotopically injecting tumor cells into the pancreas. Results: Patients who received NAC have a senescent microenvironment. High-throughput single-cell sequencing showed that the senescent gene signature score was enriched in the NAC group, especially in immune cells. The percentage of p16+ CD20+ B cells and P16+ CD3+ T cells in TLSs also increased in the NAC group. Spatial transcriptomics analysis exhibited that CD36 is highly expressed in senescent TLSs, which suggested that CD36 may be a marker for senescent TLSs. Moreover, CD36+ TLSs induced the infiltration of MDSCs and regulatory T cells. CD36+ TLSs were an independent prognostic factor for poor overall survival (OS) (HR=0.67, p=0.002) and progression-free survival (PFS) (HR=0.71, p=0.003). A mice orthotopic xenograft model showed that an anti-CD36 monoclonal antibody eliminated senescent TLSs in pancreatic tissue. MDSCs and Tregs in the surrounding tissue also decreased. Additionally, in vivo KPC mice model showed that the combination of an anti-CD36 and chemotherapy reduced tumor volume and increased survival compared to chemotherapy alone. Conclusion: NAC has the potential to induce the senescence of tumor-associated TLSs, a phenomenon that has been linked to unfavorable prognosis in PDAC. CD36 serves as a viable marker for senescent TLSs that can be targeted. The administration of an anti-CD36 monoclonal antibody can potentially enhance the efficacy of chemotherapy in PDAC by selectively eliminating CD36+ senescent TLSs in mouse models. Citation Format: Jingrui Yan, Tianxing Zhou, Chao Yang, Yongjie Xie, Jun Yu, Jihui Hao. Anti-CD36 monoclonal antibody can sensitize the neoadjuvant chemotherapy response in PDAC by eliminating the senescent tertiary lymphatic structure [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6433.

Single-cell transcriptomics reveals granzyme K–expressing cytotoxic Tfh cells in tertiary lymphoid structures in IgG4-RD

Germinal center (GC) responses controlled by T follicular helper (Tfh) and T follicular regulatory (Tfr) cells are crucial for the generation of high-affinity antibodies. Acquired immune responses to tissue-released antigens might be mainly induced in tertiary lymphoid organs (TLOs) with GCs in affected tissues. IgG4-related disease (IgG4-RD) demonstrates polarized isotype switching and TLOs in affected tissues. We performed single-cell transcriptomics of tissue-infiltrating T cells from these TLOs to obtain a comprehensive, unbiased view of tissue-infiltrating GC-Tfh cells. To identify GC-Tfh-cell subsets in TLOs in patients with IgG4-RD using single-cell transcriptomics. Single-cell RNA sequencing of sorted CD3+ T cells and multicolor immunofluorescence analysis were used to investigate CD4+CXCR5+Bcl6+ GC-Tfh cells in affected lesions from patients with IgG4-RD. Infiltrating CD4+CXCR5+Bcl6+ Tfh cells were divided into 5 main clusters. We detected HLA+ granzyme K+ (GZMK+) Tfh cells with cytotoxicity-associated features in patients with IgG4-RD. We also observed abundant infiltrating Tfr cells with suppressor-associated features in patients with IgG4-RD. These GZMK+ Tfh cells and Tfr cells clustered together in affected tissues from patients with IgG4-RD. This single-cell data set revealed a novel subset of HLA+GZMK+ cytotoxic Tfh cells infiltrating affected organs in patients with IgG4-RD, suggesting that infiltrating Tfr cells might suppress cytotoxic Tfh cells.

Association of tertiary lymphoid structures with outcomes from PD-1 inhibition in advanced malignant pleural mesothelioma.

e20545 Background: Predictive biomarkers of benefit form immunotherapy in malignant mesothelioma patients remain poorly defined. The 9-15 PROMISE-MESO study (NCT02991482) of the European Thoracic Oncology Platform (ETOP) evaluated second-line pembrolizumab against chemotherapy. Pembrolizumab led to an increased response rate compared to chemotherapy, which did not translate to survival benefits. We evaluated if the presence of tertiary lymphoid structures (TLSs) with different compositions or LRRC15+ immune suppressive fibroblasts could predict the clinical benefit from pembrolizumab. Methods: We performed multiplex immune histochemistry analysis on tumor tissues. 144 patients were included in the clinical trial, from whom, 112 had available tumor tissue for analysis: 55 patients in the chemotherapy arm, and 57 patients in the immune therapy arm. We performed the following panel: calretinin or WT1 (mesothelioma cells), CD20, CD23, CD11c, LRRC15, aSMA, and DAPI. We used the Akoya Vectra Polaris platform for analysis. The IFQuant analytical pipeline developed at the Swiss Institute for Bioinformatics (SIB) was used for analyses. Results: We defined three categories of TLSs: general CD20+ TLSs independent of other markers. CD20/CD23 double-positive as mature TLSs (mTLS), and TLSs with dendritic cells (CD11c+, cTLS). Immune suppressive CAFs were defined as LRRC15+ cells/mm2. CD20+ TLSs were identified in 84% of patients' stroma, with a median of 21 TLSs/tumor tissue and 2 TLSs/mm2. mTLSs were rare, only detected in 10 of the 112 patients (9%). cTLSs with dendritic cells were more frequent and present in 45% of all patients (50/112), and roughly half of the TLS+ patients (53%) had CD11c+ cells detected in TLSs. LRRC15+ cancer-associated fibroblasts (CAFs) were detected in 85% of patients, with a median density of 61 cells/mm2. LRRC15- tumors also contained TLSs but had significantly fewer than LRRC15+ tumors (p = 0.0079). We did not find any significant association between the responses or PFS with TLS, mTLS, and LRRC15+ CAFs. We found inverse association between cTLS levels and response to immune therapy (p = 0.037) but not for PFS. Conclusions: Our data shows that advanced malignant mesotheliomas frequently harbor TLSs, but these TLSs are mostly not activated/mature. The absence of antigen-presenting cells in TLSs, like CD11c dendritic cells, is unexpectedly associated with increased response to pembrolizumab. The high prevalence of immune suppressive LRRC15+ CAFs might explain the low response rate to pembrolizumab and could be linked to the absence of maturation of TLSs. Clinical trial information: EudraCT number: 2016-002062-31 .

Integrative analysis of tertiary lymphoid structures and immune microenvironment in patients with esophageal carcinoma.

Esophageal squamous cell carcinoma (ESCC) is one of the most common upper gastrointestinal malignancies worldwide. Tertiary lymphoid structures (TLS) are tumor-infiltrating immune cells aggregates coupled with stromal cells which are similar to secondary lymphoid organs. The objective of this study is to explore the predictive effects of two common genes associated with TLS models on prognosis and immunotherapy effects in ESCC patients. Clinical information for ESCC patients in the TCGA(The Cancer Genome Altas) cohort and GSE 53625 were collected. All of the samples were classified as either high score group or low score group based on two TLS signatures, and the association between TLS signatures and survival, clinical indicators, genomic burden, stemness indices analysis, tumor microenvironment and immunotherapy response were performed. Furthermore, the mature TLS was also assessed in ESCC tissue microarray. In our study, we quantified the score of TLS_9 and TLS_12, respectively, reflecting the different statuses of TLS (TLS_9 = B and T cells in TLSs; TLS_12 = neogenesis of TLSs). Subsequently, we explored the effect of TLS score on ESCC tumor microenvironment quantified by multiple algorithms. We found that a correlation analysis indicated that TLS_9 and TLS_12 were all positively correlated with CD8+ T cell, NK cells, CD4+ T cells, M1 macrophages and so on. Meanwhile, some cells present a different correlation pattern of TLS_9 and TLS_12, including activated CD4+ memory T cells and Tgd cells. Immune-related analysis revealed that the TLS_12 and TLS_9 scores were all positively correlated with immune dysfunction, yet negatively correlated with immune exclusion. Following this, the biological roles of TLS_9 and TLS_12 scores were investigated. Also, we noticed that the TLS score could significantly affect the CAFs infiltration and be associated with the genomic burden and tumor stemness. In addition, we explored the prognostic value of mature TLS through tissue microarray (TMA). Our result displayed ESCC patients with the presence of mature TLS had a better prognosis than ESCC patients without it. Our study indicated that ESCC patients with the presence of TLS had better outcomes and an inflamed immune microenvironment. In addition, both TLS-9 and TLS-12 gene signatures could be used as potential biomarkers for the immunotherapy of ESCC patients.

037 The intra-niche activation of clonal CXCL13+CD4+ T cells in tertiary lymphoid structures associated with non-healing blisters of pemphigus

037 The intra-niche activation of clonal CXCL13+CD4+ T cells in tertiary lymphoid structures associated with non-healing blisters of pemphigus

Cancer-Associated B Cells in Sarcoma.

Despite being one of the first types of cancers studied that hinted at a major role of the immune system in pro- and anti-tumor biology, little is known about the immune microenvironment in sarcoma. Few types of sarcoma have shown major responses to immunotherapy, and its rarity and heterogeneity makes it challenging to study. With limited systemic treatment options, further understanding of the underlying mechanisms in sarcoma immunity may prove crucial in advancing sarcoma care. While great strides have been made in the field of immunotherapy over the last few decades, most of these efforts have focused on harnessing the T cell response, with little attention on the role B cells may play in the tumor microenvironment. A growing body of evidence suggests that B cells have both pro- and anti-tumoral effects in a large variety of cancers, and in the age of bioinformatics and multi-omic analysis, the complexity of the humoral response is just being appreciated. This review explores what is currently known about the role of B cells in sarcoma, including understanding the various B cell populations associated with sarcoma, the organization of intra-tumoral B cells in tertiary lymphoid structures, recent trials in immunotherapy in sarcoma, intra-tumoral immunoglobulin, the pro-tumor effects of B cells, and exciting future areas for research.

Adverse effects of low serum lipoprotein cholesterol on the immune microenvironment in gastric cancer: a case‒control study

BackgroundCholesterol is crucial for tumor immune microenvironment (TIME) remodeling. Serum lipoprotein cholesterol is closely associated with gastric cancer (GC) progression, but whether it affects TIME remodeling is unknown.MethodsGC patients with differential serum high-density lipoprotein (HDL) or low-density lipoprotein (LDL) cholesterol levels were collected. After balancing the baseline, immunohistochemical staining was performed on serial whole-tissue sections to detect B-cell and T-cell subsets, macrophages, and PD-L1. Features of tertiary lymphoid structures (TLSs) and the extra-TLS zone, including TLS distribution and maturation, immune cell density, and PD-L1 expression, were measured by annotating TLSs or regions of interest (ROIs) in the extra-TLS zone.ResultsA total of 9,192 TLSs and over 300 ROIs from 61 patients were measured. Compared to HDL-normal patients, HDL-low patients had a decreased secondary-TLS fraction or density but an elevated NK-cell density in the extra-TLS zone. Compared to LDL-normal patients, LDL-low patients had a higher ratio of PD-1 + T follicular helper cells to CD20 + B cells in TLSs, a higher ratio of PD-1 + T cells to CD8 + T cells and increased PD-1 + T-cell density in the extra-TLS zone. Different correlations were found in groups with differential HDL or LDL levels. Cell dynamics in the immune response were weaker in patients with low lipoprotein cholesterol. TLS parameters reached their peak earlier than those of the extra-TLS zone along with tumor progression.ConclusionLow serum lipoprotein cholesterol caused adverse effects on antitumor immunity in GC. Lipid management or immunometabolic drugs deserve more attention.

Regulation of follicular T helper cell differentiation in antitumor immunity.

Follicular T helper (Tfh) cells are a subset of CD4+ T cells that play an important role in the formation of germinal centers and the maturation and differentiation of affinity-matured B cells. Recent studies have demonstrated important functions of Tfh cells in tertiary lymphoid structures of tumors, revealing great potential of Tfh cells in tumor immunity. However, Tfh development is incompletely understood. The differentiation of Tfh cells is a complex, multistage process regulated at the DNA, RNA and protein levels. This review just summarizes current research on the molecular mechanisms of Tfh cell differentiation to better understand the role of Tfh cells in antitumor immunity.

Tertiary lymphoid structures: Associated multiple immune cells and analysis their formation in hepatocellular carcinoma.

The prognostic value of immune cells in tertiary lymphoid structures (TLSs) remains unclear in hepatocellular carcinoma (HCC). Here, 59 of 145 patients had TLSs in training set, 48 of 120 patients had TLSs in testing set. Immunohistochemistry (IHC) were used to label CD3+ T cells, CD20+ B cells, CD8+ T cells, CD208+ dendritic cells, and CD21+ follicular dendritic cells in TLSs. High CD20+, CD208+, and CD8+ cell densities were favorable prognostic factors for overall survival (OS). High CD3+, CD20+, CD208+, and CD8+ cell densities were significantly associated with reduced early recurrence. TLSs were divided into three grades (A, B, and C) based on immune cell density. Patients with grade C or B had significantly improved OS. Patients with grade C had the lowest recurrence rate, followed by those with grade B, while patients with grade A had the highest recurrence rate. The stromal, immune, and ESTIMATE scores derived from the ESTIMATE package were significantly higher and tumor purity was significantly lower in patients with TLSs. Patients with TLSs had significantly higher relative numbers of memory B cells, plasma cells, CD8+ T cells, NK cells, and dendritic cells and lower relative numbers of Treg cells, macrophages, and M2 macrophages according to the CIBERSORT assessment. Bioinformatics analysis and experiments confirmed that KLRK1 and GZMA expression are associated TLSs formation and can predict TLSs existence. Grade B and grade C were favorable prognostic factors for OS and recurrence and could represent immune-active tumors.

Abstract 6109: Clonal relationship of B cells between tertiary lymphoid structures (TLSs) and tumor infiltrating lymphocytes (TILs) in advanced endometrial cancer

Abstract Objective: Tertiary lymphoid structures (TLSs) are known to be a marker of peripheral inflammation. While high densities of TLSs were reported to be associated with longer patient survival in several cancer types, there is no direct evidence where B cells in TLSs(TLBs) are derived from and whether these clones are consistent with tumor infiltrating B cells (TIBs), in endometrial cancer. Methods: We analyzed the pathological distribution of TLSs and TIBs in human endometrial cancer samples using immunohistochemistry of a series of B cell markers and evaluated the relationship with patients’ clinical outcomes. Additionally, we micro-dissected six pairs of tumor nests and their neighbor TLSs and analyzed the clonal consistency between TLBs and TIBs using the sequencing of complementarity-determining region (CDR) of B cell receptor (BCR). Results: In 104 patients with endometrial cancer, TLSs were detected in 81 patients (78%), and the absence of TLS was related to worse progression-free survival (PFS) (HR, 0.15, P <0.01). Among TLS-detected cases, the high number of TIBs was significantly associated with better PFS (P<0.05). BCR analyses in the six patients found that three patients with advanced stage had a unique B cell clones in common between TLBs and TIBs, while the other three patients with early stage did not have any common B cell clones. The frequency of common B cell clones in the former three patients were 10.3% (5250/51146 reads), 9.7% (1873/19369 reads) and 3.0% (1034/34618 reads). Conclusion: TLSs and TIBs are associated with better prognosis in endometrial cancer. Common B cell clones were found in the advanced stage cases, suggesting that B cells may have gradually acquired immunospecificity in TLSs. Citation Format: Haruka Suzuki, Junzo Hamanishi, Meng Qin, Masayo Ukita, Akihiko Ueda, Shunsuke Kawahara, Koji Yamanoi, Taito Miyamoto, Shiro Takamatsu, Mana Taki, Yoko Hosoe, Takashi Kobayashi, Ken Yamaguchi, Masaki Mandai. Clonal relationship of B cells between tertiary lymphoid structures (TLSs) and tumor infiltrating lymphocytes (TILs) in advanced endometrial cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6109.

CD20+CD22+ADAM28+ B Cells in Tertiary Lymphoid Structures Promote Immunotherapy Response.

BackgroundAs the indication for immunotherapy is rapidly expanding, it is crucial to accurately identify patients who are likely to respond. Infiltration of B cells into many tumor types correlates with a good response to immune checkpoint inhibitor (ICI) therapy. However, B cells’ roles in the anti-tumor response are far from clear.MethodsBased on single-cell transcriptomic data for ICI-treated patients, we identified a B-cell cluster [BIR (ICI-Responsive B) cells] and described the phenotype, cell–cell communication, biological processes, gene signature, and prognosis value of BIR cells through bioinformatic analysis, tissue immunofluorescence, and animal experiments. Surgery samples from 12 non-small cell lung carcinoma (NSCLC) patients with adjuvant checkpoint blockade were evaluated as external validation.ResultsBIR cells were identified as a subset of CD20+CD22+ADAM28+ B cells with a memory phenotype. Bioinformatic analysis revealed that BIR cells had enhanced cell viability and epigenetic regulation, and that ALOX5AP, MIF, and PTPRC/CD45 expressed by myeloid cells may be critical coordinators of diverse biological processes of BIR cells. Immunofluorescence confirmed the presence of BIR cells in tertiary lymphoid structures (TLSs) in skin SCC, RCC, CRC, and breast cancer. BIR-associated gene signatures correlate with positive outcomes in patients with melanoma, glioblastoma, NSCLC, HNSCC, or RCC treated with ICI therapy, and BIR-cell density predicted NSCLC patients’ response to checkpoint immunotherapy. In line with this, melanoma-bearing mice depleted of BIR cells were resistant to ICIs.ConclusionsCD20+CD22+ADAM28+ BIR cells were present in cancer-associated TLS and promoted the response to ICI therapy.

PD-1+CXCR5−CD4+ Th-CXCL13 cell subset drives B cells into tertiary lymphoid structures of nasopharyngeal carcinoma

BackgroundA major current challenge is to exploit tertiary lymphoid structures (TLSs) to promote the lymphocyte infiltration, activation and differentiation by tumor antigens to increase antitumor immune responses. The mechanisms that...

CXCL13 shapes immunoactive tumor microenvironment and enhances the efficacy of PD-1 checkpoint blockade in high-grade serous ovarian cancer

BackgroundMost patients with high-grade serous ovarian cancer (HGSC) lack an effective response to immune checkpoint blockade, highlighting the need for more knowledge about what is required for successful treatment. As...

High infiltration of B cells in tertiary lymphoid structures, TCR oligoclonality, and neoantigens are part of esophageal squamous cell carcinoma microenvironment.

Esophageal squamous cell carcinoma (ESCA) exhibits high intratumoral molecular heterogeneity posing a challenge to cancer therapy. Immune checkpoint blockade therapy has been approved for this disease, but with modest results. RNA-Seq data from paired tumor and surrounding nonmalignant tissue from 14 patients diagnosed with ESCA without previous treatment and from The Cancer Genome Atlas-ESCA cohort were analyzed. Herein, we investigated ESCA immune landscape including mutation-derived neoantigens and immune cell subpopulations. Tumor-associated antigen expression was determined by in silico analyses and confirmed by immunohistochemistry showing that PRAME, CEACAM4, and MAGEA11 proteins are expressed on tumors. Immune checkpoint molecules gene expression was higher in the tumor compared with surrounding nonmalignant tissue, but its expression varies greatly among patients. TCR repertoire and BCR transcripts analysis evidenced low clonal diversity with one TCR clone predicted to be specific for a MAGEA11-derived peptide. A high number of B-cell clones infiltrating the tumors and the abundance of these cells in tertiary lymphoid structures observed in ESCA tumors support B cells as a potential immune modulator in this tumor.

Distinct B cell signatures and tertiary lymphoid structures are driven by two etiol-ogies in head and neck cancer

Abstract B cells can regulate immune responses by presenting antigen, producing antigen-specific antibodies and immunomodulatory cytokines. Their role in the anti-tumor immune response is poorly understood. However, in many cancers including head and neck squamous cell carcinoma (HNSCC), intratumoral B cells correlate with better survival. HNSCC has two distinct etiologies (HPV−) and (HPV+) where patients who are HPV+ have increased B cell infiltration and respond better to therapy. We hypothesized that (1) intratumoral B cell phenotype is different between HPV+ and HPV− HNSCC (2) location within the tumor microenvironment (TME) is distinct and (3) antibodies produced by intratumoral B cell in HPV+ HNSCC are specific for viral antigens. Using single-cell RNA sequencing and spectral flow cytometry, we observed that B cell signatures in HPV− HNSCC patients were predominantly memory B cells and plasma cells, while the signatures in HPV+ HNSCC were naïve and germinal center (GC) B cells. Further, we quantified B cells in tertiary lymphoid structures (TLS) using multispectral immunofluorescence, and the presence of GC-rich TLS were increased in HPV+ patients. In fact, GC-rich TLS within the tumor of HPV+ patients correlated with increased overall survival. Overall, high enrichment for GC B cells were positively associated with longer progression-free survival. Antibodies produced by intratumoral B cells from HPV+ patients were positive for HPV viral antigens. Ultimately, characterization of B cell phenotype and function in HNSCC is important for devising new therapeutic options for cancer patients. Specifically, therapeutics to enhance B cell responses in the TME should be prioritized as a compliment to T-cell mediated therapies.

Immunological potential of tertiary lymphoid structures surrounding the primary tumor in gastric cancer.

Tertiary lymphoid structures (TLSs), which consist of B cells, T cells, follicular dendritic cells and high endothelial venules, have recently been found to be associated with effective antitumor immune responses in patients with cancer. Tumor-infiltrating T cells and B cells have each been demonstrated to be associated with survival in patients with cancer. We hypothesized that TLSs, an assembly of immune cells, may be important for the initiation and/or maintenance of T cell and B cell responses against tumors. The aim of the present study was to examine the cellular mechanism of B cells in TLSs within gastric cancer and to understand the antitumor immune response of TLSs. Each B cell subset in a tumor was examined using flow cytometry to evaluate B cell differentiation and the functional status of B cells. In addition, B cell clonality was investigated by analyzing the B cell antigen receptor gene using PCR, and the function and formation/maintenance of TLSs were evaluated using reverse transcription-quantitative PCR. Tumor-infiltrating B cells were more differentiated compared with that in distant non-tumor tissues and tumor-draining lymph nodes. The PCR results revealed specific BCR gene expression in tumor-infiltrating B cells. The expression of co-stimulatory factors, CD80 and CD86, was observed, in addition to the constantly expressed major histocompatibility complex molecules (HLA-ABC and HLA-DR). CD70 was expressed in addition to CD27 in both CD20+ B cells and CD8+ T cells, indicating that these factors are activated together through their interaction. The mRNA expression levels of CCL21, CXCL13, PD-L1, perforin and granzyme B in TLSs was significantly higher compared with that in non-TLSs. The majority of tumor-infiltrating B cells in gastric cancer exist in the form of TLSs around the tumor and have been antigen-sensitized and differentiated, and proliferated in TLSs but not in the lymph nodes. In addition, B cells in TLSs might primarily function as antigen-presenting cells and be associated with the induction of cytotoxic T cells.

Association of IL-36γ with tertiary lymphoid structures and inflammatory immune infiltrates in human colorectal cancer.

IL-1 family cytokines play a dual role in the gut, with different family members contributing either protective or pathogenic effects. IL-36γ is an IL-1 family cytokine involved in polarizing type-1 immune responses. However, its function in the gut, including in colorectal cancer pathogenesis, is not well appreciated. In a murine model of colon carcinoma, IL-36γ controls tertiary lymphoid structure formation and promotes a type-1 immune response concurrently with a decrease in expression of immune checkpoint molecules in the tumor microenvironment. Here, we demonstrate that IL-36γ plays a similar role in driving a pro-inflammatory phenotype in human colorectal cancer. We analyzed a cohort of 33 primary colorectal carcinoma tumors using imaging, flow cytometry, and transcriptomics to determine the pattern and role of IL-36γ expression in this disease. In the colorectal tumor microenvironment, we observed IL-36γ to be predominantly expressed by M1 macrophages and cells of the vasculature, including smooth muscle cells and high endothelial venules. This pattern of IL-36γ expression is associated with a CD4+ central memory T cell infiltrate and an increased density of B cells in tertiary lymphoid structures, as well as with markers of fibrosis. Conversely, expression of the antagonist to IL-36 signaling, IL-1F5, was associated with intratumoral expression of checkpoint molecules, including PD-1, PD-L1, and CTLA4, which can suppress the immune response. These data support a role for IL-36γ in the physiologic immune response to colorectal cancer by sustaining inflammation within the tumor microenvironment.

Specific genetic alterations and tumor immune contexture characterize ovarian tumors with paraneoplastic degeneration and anti-Yo antibodies

Background Paraneoplastic cerebellar degeneration with anti-Yo antibodies (Yo-PCD) are rare autoimmune neurological diseases triggered by ovary or breast cancers. However, mechanisms allowing breakdown of immune tolerance to tumor antigens (Ags) are still unclear. Methods We collected 25 samples of Yo-PCD ovarian cancers to analyze the immunohistological (IHC) characteristics of these tumors and to perform genomic study by aCGH and NGS. We compared the results to 116 ovarian tumors without Yo-PCD. Results Yo-PCD ovarian tumors strikingly differ from those of non-PCD patients. Although 23 out of 25 are histologically classical high-grade serous carcinoma, they are characterized by increased immune cell infiltration, organization of T and B cells in tertiary lymphoid structures and presence of mature DC in contact with tumor cells. Analyzing the genes encoding for the Yo Ags, e.g. CDR2 and CDR2L, CGH revealed significant recurrent gains in CDR2L gene copy numbers in Yo-PCD tumors. CDR2L overexpression was detected by IHC in all Yo-PCD ovarian cancers. Moreover, NGS analysis revealed that 65% of the Yo-PCD ovarian cancer presented missense or non-sense mutations in at least 1 of the Yo Ags, while only 0.1% of un-selected ovarian tumors were mutated. No constitutional mutations were detected in Yo-PCD patients. Finally, all but 2 Yo-PCD ovarian cancers carried at least one genetic alteration on CDR2 or CDR2L genes (gains and/or mutations). Conclusions Altogether, these data show that genetic alteration of onconeural Ags, including gains and mutations, might be instrumental for induction of the remarkable anti-tumor immune response characterizing PCD.

B cells in tertiary lymphoid structures are associated with favorable prognosis in gastric cancer

BackgroundThe role of tumor-infiltrating B cells in the tumor microenvironment is still unclear. Recent studies have reported that B cells and tertiary lymphoid structures (TLSs) that contain B cell follicles correlate with the favorable prognosis of cancer patients. The aim of this study was to investigate the association between tumor-infiltrating B cells and clinicopathological features in gastric cancer. MethodsTumor blocks were obtained from 226 patients with stage Ib to stage IV gastric cancer. The density of CD20+ B cells within the tumor and in the invasive margin area was assessed using immunohistochemistry. We also evaluated CD3+ T cells, CD21+ follicular dendritic cells, Bcl6+ germinal center B cells, and PNAd+ high endothelial venules to show the presence of TLSs. ResultsTumor-infiltrating B cells were mostly organized as clusters that were surrounded by CD3+ T cells. The B cell area contained follicular dendritic cells and some clusters contained Bcl6+ B cells. High endothelial venules were present around follicles. We identified these follicles as TLSs. A high number of CD20+ B cells were associated with significantly better overall survival, and multivariate analysis also showed that CD20 high was one of the independent predictors of prognosis. In addition, there was a significant correlation between CD20+ B cell and CD8+ T cell infiltration. ConclusionsB cells mostly infiltrated tumors as TLSs and were associated with better prognosis in patients with gastric cancer.

Presence of B Cells in Tertiary Lymphoid Structures Is Associated with a Protective Immunity in Patients with Lung Cancer

It is now well established that immune responses can take place outside of primary and secondary lymphoid organs. We previously described the presence of tertiary lymphoid structures (TLS) in patients with non-small cell lung cancer (NSCLC) characterized by clusters of mature dendritic cells (DCs) and T cells surrounded by B-cell follicles. We demonstrated that the density of these mature DCs was associated with favorable clinical outcome. To study the role of follicular B cells in TLS and the potential link with a local humoral immune response in patients with NSCLC. The cellular composition of TLS was investigated by immunohistochemistry. Characterization of B-cell subsets was performed by flow cytometry. A retrospective study was conducted in two independent cohorts of patients. Antibody specificity was analyzed by ELISA. Consistent with TLS organization, all stages of B-cell differentiation were detectable in most tumors. Germinal center somatic hypermutation and class switch recombination machineries were activated, associated with the generation of plasma cells. Approximately half of the patients showed antibody reactivity against up to 7 out of the 33 tumor antigens tested. A high density of follicular B cells correlated with long-term survival, both in patients with early-stage NSCLC and with advanced-stage NSCLC treated with chemotherapy. The combination of follicular B cell and mature DC densities allowed the identification of patients with the best clinical outcome. B-cell density represents a new prognostic biomarker for NSCLC patient survival, and makes the link between TLS and a protective B cell-mediated immunity.