Dendritic cells can prime anti-tumor CD8+ T cell responses through major histocompatibility complex cross-dressing.

Antigen cross-presentation, wherein dendritic cells (DCs) present exogenous antigen on major histocompatibility class I (MHC-I) molecules, is considered the primary mechanism by which DCs initiate tumor-specific CD8+ T cell responses. Here, we demonstrate that MHC-I cross-dressing, an antigen presentation pathway in which DCs acquire and display intact tumor-derived peptide:MHC-I molecules, is also important in orchestrating anti-tumor immunity. Cancer cell MHC-I expression was required for optimal CD8+ T cell activation in two subcutaneous tumor models. In vivo acquisition of tumor-derived peptide:MHC-I molecules by DCs was sufficient to induce antigen-specific CD8+ T cell priming. Transfer of tumor-derived human leukocyte antigen (HLA) molecules to myeloid cells was detected in vitro and in human tumor xenografts. In conclusion, MHC-I cross-dressing is crucial for anti-tumor CD8+ T cell priming by DCs. In addition to quantitatively enhancing tumor antigen presentation, MHC cross-dressing might also enable DCs to more faithfully and efficiently mirror the cancer cell peptidome.

Trans-vaccenic acid reprograms CD8+ T cells and anti-tumour immunity.

Diet-derived nutrients are inextricably linked to human physiology by providing energy and biosynthetic building blocks and by functioning as regulatory molecules. However, the mechanisms by which circulating nutrients in the human body influence specific physiological processes remain largely unknown. Here we use a blood nutrient compound library-based screening approach to demonstrate that dietary trans-vaccenic acid (TVA) directly promotes effector CD8+ T cell function and anti-tumour immunity in vivo. TVA is the predominant form of trans-fatty acids enriched in human milk, but the human body cannot produce TVA endogenously1. Circulating TVA in humans is mainly from ruminant-derived foods including beef, lamb and dairy products such as milk and butter2,3, but only around 19% or 12% of dietary TVA is converted to rumenic acid by humans or mice, respectively4,5. Mechanistically, TVA inactivates the cell-surface receptor GPR43, an immunomodulatory G protein-coupled receptor activated by its short-chain fatty acid ligands6-8. TVA thus antagonizes the short-chain fatty acid agonists of GPR43, leading to activation of the cAMP-PKA-CREB axis for enhanced CD8+ T cell function. These findings reveal that diet-derived TVA represents a mechanism for host-extrinsic reprogramming of CD8+ T cells as opposed to the intrahost gut microbiota-derived short-chain fatty acids. TVA thus has translational potential for the treatment of tumours.

[Effect of origin, tree age, and harvesting time on content of flavonoids and terpene lactones in Ginkgo Folium].

The content of total flavonol glycosides in Ginkgo Folium in the planting bases was determined by high performance liquid chromatography(HPLC).The samples were extracted by reflux with methanol-25% hydrochloric acid.The HPLC conditions were as follows: Agilent ZORBAX SB-C_(18) column(4.6 mm×250 mm, 5 µm), isocratic elution with mobile phase of 0.4% phosphoric acid solution-methanol(45∶55), flow rate of 1 mL·min~(-1), column temperature of 30 ℃, detection wavelength of 360 nm, and injection vo-lume of 10 µL.A method for the determination of terpene lactones in Ginkgo Folium was established based on ultra-high performance liquid chromatograph-triple-quadrupole/linear ion-trap tandem mass spectrometry(UPLC-QTRAP-MS/MS).The UPLC conditions were as below: gradient elution with acetonitrile-0.1% formic acid, flow rate of 0.2 mL·min~(-1), column temperature of 30 ℃, sample chamber temperature of 10 ℃, and injection volume of 10 µL.The ESI~+and multiple reaction monitoring(MRM) were adopted for the MS.The above methods were used to determine the content of total flavonol glycosides and terpene lactones in 99 batches of Ginkgo Folium from 6 planting bases, and the results were statistically analyzed.The content of flavonoids and terpene lactones in Ginkgo Folium from different origins, from trees of different ages, harvested at different time, from trees of different genders, and processed with different methods was compared.The results showed that the content of total flavonol glucosides in 99 Ginkgo Folium samples ranged from 0.38% to 2.08%, and the total content of the four terpene lactones was in the range of 0.03%-0.87%.The method established in this study is simple and reliable, which can be used for the quantitative analysis of Ginkgo Folium.The research results lay a basis for the quality control of Ginkgo Folium.

Negligible Role for Deletion Mediated by cDC1 in CD8+ T Cell Tolerance.

Deletion of CD8+ T cells by dendritic cells (DCs) is recognized as a critical mechanism of immune tolerance to self-antigens. Although DC-mediated peripheral deletion of autoreactive CD8+ T cells has been demonstrated using T cells reactive to model Ags, its role in shaping the naturally occurring polyclonal CD8+ T cell repertoire has not been defined. Using Batf3-/- mice lacking cross-presenting CD8α+ and CD103+ DCs (also known as type 1 conventional [cDC1]), we demonstrate that peripheral deletion of CD8+ T cells reactive to a model tissue Ag is dependent on cDC1. However, endogenous CD8+ T cells from the periphery of Batf3-/- mice do not exhibit heightened self-reactivity, and deep TCR sequencing of CD8+ T cells from Batf3-/- and Batf3+/+ mice reveals that cDC1 have a minimal impact on shaping the peripheral CD8+ T cell repertoire. Thus, although evident in reductionist systems, deletion of polyclonal self-specific CD8+ T cells by cDC1 plays a negligible role in enforcing tolerance to natural self-ligands.

[Determination of caffeine content in Ginkgo Folium by ultra high performance liquid chromatography-triple quadrupole mass spectrometry].

In this experiment, an ultra-high performance liquid chromatographytandem triple quadrupole mass spectrometry was established for the determination of caffeine in commercially available Ginkgo Folium. The samples were extracted by ultrasonic method with methanol, and separated on Waters CORTECS T3 column(2.1 mm×100 mm, 2.7 µm), with mobile phase of 0.1% formic acid solution-0.1% formic acid acetonitrile solution for gradient elution, at flow rate of 0.3 mL·min~(-1); column temperature of 30 ℃, and injection volume of 2 µL. Mass spectrometry was conducted at ESI~+ multiple reaction monitoring(MRM) mode; quantitative analysis was conducted with external standard method. The results showed that in the range of 0.099 6-9.96 ng·mL~(-1), there was a good linear relationship between the mass concentration of caffeine and the peak area, R~2=0.999; the average recovery was 84.51%, with RSD of 6.2%. The results of precision, repeatability and stability showed that the RSD was 5.1%, 5.9%, 7.2%, respectively. The content range of caffeine in 10 batches of Ginkgo Folium was 1.52-60.86 µg·kg~(-1). In conclusion, this method is accurate, reliable and reproducible, which provides a reference for the safety study of Ginkgo Folium.

Calreticulin exposure on malignant blasts correlates with improved natural killer cell-mediated cytotoxicity in acute myeloid leukemia patients.

In some settings, cancer cells responding to treatment undergo an immunogenic form of cell death that is associated with the abundant emission of danger signals in the form of damage-associated molecular patterns. Accumulating preclinical and clinical evidence indicates that danger signals play a crucial role in the (re-)activation of antitumor immune responses in vivo, thus having a major impact on patient prognosis. We have previously demonstrated that the presence of calreticulin on the surface of malignant blasts is a positive prognostic biomarker for patients with acute myeloid leukemia (AML). Calreticulin exposure not only correlated with enhanced T-cell-dependent antitumor immunity in this setting but also affected the number of circulating natural killer (NK) cells upon restoration of normal hematopoiesis. Here, we report that calreticulin exposure on malignant blasts is associated with enhanced NK cell cytotoxic and secretory functions, both in AML patients and in vivo in mice. The ability of calreticulin to stimulate NK-cells relies on CD11c+CD14high cells that, upon exposure to CRT, express higher levels of IL-15Rα, maturation markers (CD86 and HLA-DR) and CCR7. CRT exposure on malignant blasts also correlates with the upregulation of genes coding for type I interferon. This suggests that CD11c+CD14high cells have increased capacity to migrate to secondary lymphoid organs, where can efficiently deliver stimulatory signals (IL-15Rα/IL-15) to NK cells. These findings delineate a multipronged, clinically relevant mechanism whereby surface-exposed calreticulin favors NK-cell activation in AML patients.

CD8α+ Dendritic Cells Dictate Leukemia-Specific CD8+ T Cell Fates.

APCs are essential for the orchestration of antitumor T cell responses. Batf3-lineage CD8α+ and CD103+ dendritic cells (DCs), in particular, are required for the spontaneous initiation of CD8+ T cell priming against solid tumors. In contrast, little is known about the APCs that regulate CD8+ T cell responses against hematological malignancies. Using an unbiased approach, we aimed to characterize the APCs responsible for regulating CD8+ T cell responses in a syngeneic murine leukemia model. We show with single-cell resolution that CD8α+ DCs alone acquire and cross-present leukemia Ags in vivo, culminating in the induction of leukemia-specific CD8+ T cell tolerance. Furthermore, we demonstrate that the mere acquisition of leukemia cell cargo is associated with a unique transcriptional program that may be important in regulating tolerogenic CD8α+ DC functions in mice with leukemia. Finally, we show that systemic CD8α+ DC activation with a TLR3 agonist completely prevents their ability to generate leukemia-specific CD8+ T cell tolerance in vivo, resulting instead in the induction of potent antileukemia T cell immunity and prolonged survival of leukemia-bearing mice. Together, our data reveal that Batf3-lineage DCs imprint disparate CD8+ T cell fates in hosts with solid tumors versus systemic leukemia.

The impact of food additives, artificial sweeteners and domestic hygiene products on the human gut microbiome and its fibre fermentation capacity.

PURPOSE: This study investigated the effect of food additives, artificial sweeteners and domestic hygiene products on the gut microbiome and fibre fermentation capacity. METHODS: Faecal samples from 13 healthy volunteers were fermented in batch cultures with food additives (maltodextrin, carboxymethyl cellulose, polysorbate-80, carrageenan-kappa, cinnamaldehyde, sodium benzoate, sodium sulphite, titanium dioxide), sweeteners (aspartame-based sweetener, sucralose, stevia) and domestic hygiene products (toothpaste and dishwashing detergent). Short-chain fatty acid production was measured with gas chromatography. Microbiome composition was characterised with 16S rRNA sequencing and quantitative polymerase chain reaction (qPCR). RESULTS: Acetic acid increased in the presence of maltodextrin and the aspartame-based sweetener and decreased with dishwashing detergent or sodium sulphite. Propionic acid increased with maltodextrin, aspartame-based sweetener, sodium sulphite and polysorbate-80 and butyrate decreased dramatically with cinnamaldehyde and dishwashing detergent. Branched-chain fatty acids decreased with maltodextrin, aspartame-based sweetener, cinnamaldehyde, sodium benzoate and dishwashing detergent. Microbiome Shannon α-diversity increased with stevia and decreased with dishwashing detergent and cinnamaldehyde. Sucralose, cinnamaldehyde, titanium dioxide, polysorbate-80 and dishwashing detergent shifted microbiome community structure; the effects were most profound with dishwashing detergent (R2 = 43.9%, p = 0.008) followed by cinnamaldehyde (R2 = 12.8%, p = 0.016). Addition of dishwashing detergent and cinnamaldehyde increased the abundance of operational taxonomic unit (OTUs) belonging to Escherichia/Shigella and Klebsiella and decreased members of Firmicutes, including OTUs of Faecalibacterium and Subdoligranulum. Addition of sucralose and carrageenan-kappa also increased the abundance of Escherichia/Shigella and sucralose, sodium sulphite and polysorbate-80 did likewise to Bilophila. Polysorbate-80 decreased the abundance of OTUs of Faecalibacterium and Subdoligranulum. Similar effects were observed with the concentration of major bacterial groups using qPCR. In addition, maltodextrin, aspartame-based sweetener and sodium benzoate promoted the growth of Bifidobacterium whereas sodium sulphite, carrageenan-kappa, polysorbate-80 and dishwashing detergent had an inhibitory effect. CONCLUSIONS: This study improves understanding of how additives might affect the gut microbiota composition and its fibre metabolic activity with many possible implications for human health.

[Visual analysis of coronavirus disease 2019 (COVID-19) studies based on bibliometrics].

To analyze the development of coronavirus disease 2019(COVID-19), this study systematically retrieved relevant Chinese and English literatures from both CNKI and Web of Science database platforms by bibliometric research method and CiteSpace 5.5.R2 software to obtain information and visualize relevant literatures. A total of 695 Chinese and 446 English literatures were included in this paper. Statistics showed that China had published most of the literatures and established close cooperation with the United States and the United Kingdom. Through the analysis, Tongji Medical College of Huazhong University of Science and Technology and its affiliated hospitals published the largest number of the publications. Moreover, the highly productive journals including Journal of Traditional Chinese Medicine and The Lancet covered eight major fields, such as medicine, medical virology, radiation medicine, infectious disease, and traditional Chinese medicine. Besides, a total of 35 special COVID-19 funds were recently established to subsidize these studies. The key words and themes analysis indicated that protein structure of COVID-19, receptor targets and mechanisms of action, integration of traditional Chinese and Western medicine, screening and development of antiviral drugs from traditional Chinese medicine and Western medicine, vaccine research as well as epidemiological characteristics and prediction are current study hotspots. This study provides a reference for researchers to rapidly master main study directions of COVID-19 and screen out relevant literatures.

Smooth muscle cell-specific knockout of FBW7 exacerbates intracranial atherosclerotic stenosis.

Intracranial atherosclerotic stenosis (ICAS), the most common cause of stroke worldwide, is associated with high risk of recurrent ischemic stroke. F-box and WD repeat domain containing protein 7 (FBW7), an ubiquitin E3 ligase, is recently suggested to be involved in atherogenesis. However, whether FBW7 affects cerebrovascular remodeling during ICAS remains unknowns. We found that the expression of FBW7 was decreased in mouse brain microvessels from high-fat diet (HFD)-fed atherosclerotic mice. The reduced FBW7 expression was negatively associated with the remodeling of middle cerebral artery (MCA). Specific loss of FBW7 in smooth muscle cells (SMCs) markedly potentiated brain vascular SMC (VSMC) proliferation, migration and subsequent MCA remodeling in atherosclerotic mice. The increase of total reactive oxygen species (ROS) generation and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity in brain microvessels and VSMCs were enhanced after knockout of FBW7, while the mitochondria-derived ROS was unchanged. Analysis of several key subunits of NADPH oxidase revealed that FBW7 deficiency augmented HFD-induced the increase of Nox1 expression, but had no effect on p47phox and p67phox phosphorylation as well as p22phox expression. Both NADPH oxidase specific inhibitor and Nox1 downregulation abrogated the effects of FBW7 deficiency on MCA remodeling. Immunoprecipitation assay identified that FBW7 interacted with Nox1. FBW7 knockout increased Nox1 protein stability by inhibiting ubiquitin-mediated degradation. Collectively, our study demonstrates that SMC-specific deficiency of FBW7 exacerbates ICAS by facilitating Nox1-derived ROS generation, VSMC proliferation and cerebrovascular remodeling.

[Effect of lead pollution on anticoagulant effect of Whitmania pigra based on in vitro anticoagulation experiment].

Leech has a good anticoagulant activity and is one of the raw materials for treatment of many cardiovascular and cerebrovascular diseases. This study was based on in vitro anticoagulant experiments( APTT and PT) to investigate the effects of lead contamination on the anticoagulant effect of leech. At present,the Hirudo circulating in the market are dominated by Whitmania pigra,therefore Wh. pigra were cultivated under a different lead pollution for 50 days. Then,the effects of Wh. pigra extract,extracting from different cultivating environment,on activated partial thrombin time( APTT) and prothrombin time( PT) were determined by automatic coagulation instrument. The results showed that the Wh. pigra extract significantly prolonged the APTT compared with the saline group.The APTT of the lead-high residual Wh. pigra was shorter than that of the blank Wh. pigra. The Wh. pigra extracts from different treatment groups had little effect on PT. The results showed that the lead residue in the Wh. pigra increased with the increase of lead in the cultured soil,the lead residual of the Pb-H group was( 10. 66±2. 79) mg·kg~(-1),which exceeded the lead limit specified in the 2015 edition of the Chinese Pharmacopoeia. The results indicated that growth environment pollution is one of the important factors causing excessive lead in Wh. pigra. Lead pollution will reduce the anticoagulant effect of Wh. pigra and affect its clinical efficacy.

[Diversity of fungi on surface of Pheretima].

Traditional Chinese medicines( TCMs) are easily contaminated by fungi during planting,harvesting,processing,transportation and storage. The 2015 version of Chinese Pharmacopoeia stipulates the detection of aflatoxin in Dilong. After reviewing the literature,it has been found that there are no domestic and foreign scholars who have studied the surface fungi of Dilong. Pheretima,known as Dilong in China,is a commonly used TCMs in animal. In this experiment,8 batches of Dilong were collected from retail pharmacies in Beijing. The fungi on the surface of Dilong were cultured by traditional plate method and the single strain was obtained by the top purification method. The fungal colony morphology,microstructure characteristics and DNA barcode were used to isolate and identify the fungi. At the same time,based on Illumina Hi Seq 2500 high-throughput sequencing platform,the diversity of fungi on the surface of Dilong was analyzed. The results showed that 287 strains of 9 species of fungi were isolated and identified by plate method. Combined with 3 kinds of identification method,eight of nine fungi could be identified,respectively,Aspergillus niger,Penicillium,Alternaria nees,A. flavus,and Penicillium oxalicum,Humicola sp.,Talaromyces purpurogenus and A. insuetus,1 kind of fungi was not identified yet. Among them,Penicillium and Aspergillus were the dominant genus. The results of high-throughput sequencing belonged to 2 boundaries,6 gates,19 classes,44 orders,98 families,127 genus and 121 species in different classification levels. Wallemia,Aspergillus and Cordyceps were the dominant genus,and the relative abundances are 63. 33%,15. 28%,and 10. 28%,respectively. Through the diversity study on the surface fungi of Dilong in Beijing retail pharmacies,it can provide a reference for its safe storage and clinical use.

MicroRNA-182-5p attenuates cerebral ischemia-reperfusion injury by targeting Toll-like receptor 4.

Cerebral ischemia-reperfusion-induced microglial activation causes neuronal death through the release of inflammatory cytokines. Increasing evidence suggests that microRNAs (miRNAs) exert a neuroprotective effect by modulating the inflammatory process in cerebral ischemia-reperfusion injury. Furthermore, Toll-like receptor 4 (TLR4) is increasingly being considered to have a significant role in the regulation of inflammation. However, whether miRNAs mediate their neuroprotective effects by regulating TLR4-mediated inflammatory responses remains unknown. To explore this gap in the literature, we conducted both in vitro and in vivo experiments. In vitro: BV2 cells were activated by oxygen-glucose deprivation (OGD). TLR4 and inflammatory cytokine (TNF-a, IL-6, and IL-1ß) transcription and translation expression levels were assessed using RT-PCR, ELISA, and western blot. BV2 cells were transfected with miR-182-5p mimics, inhibitors, siTLR4, or negative control (NC) using lipofectamine 2000 reagent. To confirm whether TLR4 is a direct target of miR-182-5p, we performed a luciferase reporter assay. In BV2 cells, we observed that OGD upregulated TLR4 expression, but downregulated miR-182-5p expression. We determined that miR-182-5p inhibited TLR4 by directly binding to its 3'-UTR. Furthermore, miR-182-5p suppressed the release of TNF-a, IL-6, and IL-1ß. In vivo: A middle cerebral artery occlusion (MCAO) rat model was used to mimic cerebral ischemia-reperfusion. Iba1 and TLR4 double staining was used to demonstrate that the target of miR-182-5p in microglial cells, and the mediator of the anti-inflammatory effect, is TLR4. TTC staining was performed to evaluate the infarct volume. Compared to the animals treated with miR-182-5p NC and normal saline, rats treated with miR-182-5p mimics demonstrated significantly enhanced neurological functions. TTC staining results were consistent with neurological function test findings. In summary, our data suggested that miR-182-5p exhibits potential neuroprotective effects in the cerebral ischemia-reperfusion injury via the regulation of the TLR4-mediated inflammatory response.

PD-1 regulates extrathymic regulatory T-cell differentiation.

Treg cells and the programed death-1/programed death ligand-1 (PD-1/PD-L1) pathway are both critical for maintaining peripheral tolerance to self-Ags. A significant subset of Treg cells constitutively expresses PD-1, which prompted an investigation into the role of PD-1/PD-L1 interactions in Treg-cell development, function, and induction in vivo. The phenotype and abundance of Treg cells was not significantly altered in PD-1-deficient mice. The thymic development of polyclonal and monospecific Treg cells was not negatively impacted by PD-1 deficiency. The suppressive function of PD-1(-/-) Treg cells was similar to their PD-1(+/+) counterparts both in vitro and in vivo. However, in three different in vivo experimental settings, PD-1(-/-) conventional CD4(+) T cells demonstrated a strikingly diminished tendency toward differentiation into peripherally induced Treg (pTreg) cells. Our results demonstrate that PD-1 is dispensable for thymic Treg-cell development and suppressive function, but is critical for the extrathymic differentiation of pTreg cells in vivo. These data suggest that Ab blockade of the PD-1/PD-L1 pathway may augment T-cell responses by acting directly on conventional T cells, and also by suppressing the differentiation of pTreg cells.

T-cell States, Repertoire, and Function in Classical Hodgkin Lymphoma Revealed through Single-Cell Analyses.

The classical Hodgkin lymphoma (cHL) environment is comprised of a dense and complex immune cell infiltrate interspersed with rare malignant Hodgkin-Reed-Sternberg (HRS) cells. HRS cells are actively surveilled by endogenous T cells, but data linking phenotypic and functional T-cell states with clonality at the single-cell level in cHL is lacking. To address this knowledge gap, we performed paired single-cell RNA and T-cell receptor sequencing on 14 cHL and 5 reactive lymphoid tissue specimens. Conventional CD4+ T cells dominated the cHL landscape. However, recurrent clonal expansion within effector and exhausted CD8+ T-cell and regulatory T-cell clusters was uniquely observed in cHL specimens. Multiplex flow cytometric analysis revealed that most lymphoma-resident T cells produced effector cytokines upon ex vivo restimulation, arguing against a profound dysfunctional T-cell state in cHL. Our results raise new questions about the nature of T cells that mediate the antilymphoma response following programmed cell death protein 1 (PD-1) blockade therapy in cHL.

Integrative genomic analysis identifies unique immune environments associated with immunotherapy response in diffuse large B cell lymphoma.

Most diffuse large B-cell lymphoma (DLBCL) patients treated with bispecific antibodies (BsAb) or chimeric antigen receptor (CAR) T cells fail to achieve durable treatment responses, underscoring the need for a deeper understanding of mechanisms that regulate the immune environment and response to treatment. Here, an integrative, multi-omic approach was employed to characterize DLBCL immune environments, which effectively segregated DLBCLs into four quadrants - termed DLBCL-immune quadrants (IQ) - defined by cell-of-origin and immune-related gene set expression scores. Recurrent genomic alterations were enriched in each IQ, suggesting that lymphoma cell-intrinsic alterations contribute to orchestrating unique DLBCL immune environments. In relapsed/refractory DLBCL patients, DLBCL-IQ assignment correlated significantly with clinical benefit with the CD20 x CD3 BsAb, mosunetuzumab, but not with CD19-directed CAR T cells. DLBCL-IQ provides a new framework to conceptualize the DLBCL immune landscape and uncovers the differential impact of the endogenous immune environment on outcomes to BsAb and CAR T cell treatment.

A Rare Case of Basal Cell Adenocarcinoma of the Right Submandibular Gland.

Basal cell adenocarcinoma of the submandibular gland is an extremely rare carcinoma of the salivary gland that originates from the basal cells of the submandibular gland. Due to its rarity, there are relatively few case reports and literature on this cancer. After comprehensive clinical, imaging, and pathologic analyses, we confirmed the patient's diagnosis and documented the consultation in detail. The purpose of this article is to report the case of a patient with basal cell adenocarcinoma of the submandibular gland and to perform a review of the relevant literature to improve the understanding of this rare disease.

AVPR2 is a potential prognostic biomarker and correlated with immune infiltration in head and neck squamous cell carcinoma.

PURPOSE: To explore the potential of AVPR2 in the immunotherapy of head and neck squamous cell carcinoma (HNSCC), thus providing insights into a novel antitumour strategy. METHODS: In this study, we performed a comprehensive analysis of the AVPR2 gene in HNSCC using public datasets from The Cancer Genome Atlas and Gene Expression Omnibus. We explored the potential molecular mechanism of HNSCC in clinical prognosis and tumour immunity from the aspects of gene expression, prognosis, immune subtypes, and immune infiltration. RESULTS: AVPR2 expression was significantly downregulated in primary HNSCC tissue compared with normal tissue. HNSCC patients with high AVPR2 expression had a better prognosis. Moreover, the results of GSEA showed that immune subtype surface AVPR2 is involved in immune modulation. Furthermore, significant strong correlations between AVPR2 expression and infiltrating immune cells existed in HNSCC, and marker genes of infiltrating immune cells were also significantly related to AVPR2 expression in HNSCC. These results suggest that AVPR2 expression can influence the infiltration of tumour immune cells. Finally, we found that only high levels of B-cell infiltration, rather than those of other immune cells, can predict a longer overall survival in patients with HNSCC. Future studies are needed to explore the role of AVPR2 and tumour-infiltrating B cells in HNSCC. CONCLUSIONS: The AVPR2 gene may be a prognostic biomarker of HNSCC. Moreover, AVPR2 may play a role in HNSCC immune modulation, and the regulation of tumour-infiltrating B cells by AVPR2 may be a key link.

TIGIT is a key inhibitory checkpoint receptor in lymphoma.

BACKGROUND: PD-1 checkpoint blockade therapy (CBT) has greatly benefited patients with select solid tumors and lymphomas but has limited efficacy against diffuse large B-cell lymphoma (DLBCL). Because numerous inhibitory checkpoint receptors have been implicated in driving tumor-specific T cell dysfunction, we hypothesized that combinatorial CBT would enhance the activity of anti-PD-1-based therapy in DLBCL. T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT) is a coinhibitory receptor expressed on dysfunctional tumor-infiltrating T cells, and TIGIT blockade has demonstrated encouraging activity in combination with PD-1 blockade in murine tumor models and in clinical studies. However, the degree to which TIGIT mediates T cell dysfunction in DLBCL has not been fully explored. RESULTS: Here, we demonstrate that TIGIT is broadly expressed on lymphoma-infiltrating T cells (LITs) across a variety of human lymphomas and is frequently coexpressed with PD-1. TIGIT expression is particularly common on LITs in DLBCL, where TIGIT+ LITs often form distinct cellular communities and exhibit significant contact with malignant B cells. TIGIT+/PD-1+ LITs from human DLBCL and murine lymphomas exhibit hypofunctional cytokine production on ex vivo restimulation. In mice with established, syngeneic A20 B-cell lymphomas, TIGIT or PD-1 mono-blockade leads to modest delays in tumor outgrowth, whereas PD-1 and TIGIT co-blockade results in complete rejection of A20 lymphomas in most mice and significantly prolongs survival compared with mice treated with monoblockade therapy. CONCLUSIONS: These results provide rationale for clinical investigation of TIGIT and PD-1 blockade in lymphomas, including DLBCL.