Effects of PACAP Deficiency on Immune Dysfunction and Peyer's Patch Integrity in Adult Mice.

PACAP (pituitary adenylate cyclase activating polypeptide) is a widespread neuropeptide with cytoprotective and anti-inflammatory effects. It plays a role in innate and adaptive immunity, but data are limited about gut-associated lymphoid tissue. We aimed to reveal differences in Peyer's patches between wild-type (WT) and PACAP-deficient (KO) mice. Peyer's patch morphology from young (3-months-old) and aging (12-15-months-old) mice was examined, along with flow cytometry to assess immune cell populations, expression of checkpoint molecules (PD-1, PD-L1, TIM-3, Gal-9) and functional markers (CD69, granzyme B, perforin) in CD3+, CD4+, and CD8+ T cells. We found slight differences between aging, but not in young, WT, and KO mice. In WT mice, aging reduced CD8+ T cell numbers frequency and altered checkpoint molecule expression (higher TIM-3, granzyme B; lower Gal-9, CD69). CD4+ T cell frequency was higher with similar checkpoint alterations, indicating a regulatory shift. In PACAP KO mice, aging did not change cell population frequencies but led to higher TIM-3, granzyme B and lower PD-1, PD-L1, Gal-9, and CD69 expression in CD4+ and CD8+ T cells, with reduced overall T cell activity. Thus, PACAP deficiency impacts immune dysfunction by altering checkpoint molecules and T cell functionality, particularly in CD8+ T cells, suggesting complex immune responses by PACAP, highlighting its role in intestinal homeostasis and potential implications for inflammatory bowel diseases.

Effects of Ruxolitinib on Immune Checkpoint Molecule Expression in JAK2 V617F-Positive Cells.

BACKGROUND: This study aimed to explore the clinical significance of ruxolitinib and its effects on the proliferation and apoptosis of human erythroleukemia (HEL) cells and the expression of immune checkpoint molecules programmed death-1 (PD-1), programmed death-ligand 1 (PD-L1), and regulatory T cells (Tregs) in HEL cells and JAK2 V617F-positive patients with myeloproliferative neoplasms (MPNs). METHODS: JAK2 V617F-positive patients with MPNs admitted to the Baoding No. 1 Hospital from January 2016 to September 2023 were recruited, including 30 patients for the newly diagnosed group and 10 for the treatment group. Additionally, 15 healthy volunteers were selected as the control group. JAK2 V617F mutation was detected by using fluorescence quantitative PCR, and the expression levels of phosphorylated JAK2 (p-JAK2), PD-1, and PD-L1 in fresh bone marrow were examined by immunohistochemistry. HEL cells were treated with ruxolitinib at different concentrations (0, 50, 100, 250, 500, and 1,000 nmol/L). Cell viability was detected by CCK-8 assay. The mRNA expression levels of JAK2, PD-1, and PD-L1 were determined by using fluorescence quantitative PCR. The protein expression of p-JAK2 was detected by Western blot and those of PD-1 and PD-L1 were evaluated by flow cytometry. The expression of PD-1, PD-L1, and Tregs after the 48-hour co-culture of primary bone marrow cells and HEL cells were also analyzed by flow cytometry. RESULTS: In the newly diagnosed group, the bone marrow myeloid cells highly expressed p-JAK2, PD-1, and PD-L1. The Tregs expression in their peripheral blood increased and was significantly higher than those in the treatment and control groups (all p < 0.05). Ruxolitinib at different concentrations could inhibit the proliferation of HEL cells and was positively correlated with treatment time and dose. Additionally, ruxolitinib could reduce p-JAK2, PD-1, and PD-L1 expression in HEL cells and Tregs expression. CONCLUSIONS: Ruxolitinib reduces the expression of p-JAK2, PD-1, and PD-L1 in JAK2 V617F-positive cells by specifically inhibiting the JAK2 signaling pathway, thereby suppressing the progression of MPNs.

Systemic longitudinal immune profiling identifies proliferating Treg cells as predictors of immunotherapy benefit: biomarker analysis from the phase 3 CONTINUUM and DIPPER trials.

The identification of predictors for immunotherapy is often hampered by the absence of control groups in many studies, making it difficult to distinguish between prognostic and predictive biomarkers. This study presents biomarker analyses from the phase 3 CONTINUUM trial (NCT03700476), the first to show that adding anti-PD-1 (aPD1) to chemoradiotherapy (CRT) improves event-free survival (EFS) in patients with locoregionally advanced nasopharyngeal carcinoma. A dynamic single-cell atlas was profiled using mass cytometry on peripheral blood mononuclear cell samples from 12 pairs of matched relapsing and non-relapsing patients in the aPD1-CRT arm. Using a supervised representation learning algorithm, we identified a Ki67+ proliferating regulatory T cells (Tregs) population expressing high levels of activated and immunosuppressive molecules including FOXP3, CD38, HLA-DR, CD39, and PD-1, whose abundance correlated with treatment outcome. The frequency of these Ki67+ Tregs was significantly higher at baseline and increased during treatment in patients who relapsed compared to non-relapsers. Further validation through flow cytometry (n = 120) confirmed the predictive value of this Treg subset. Multiplex immunohistochemistry (n = 249) demonstrated that Ki67+ Tregs in tumors could predict immunotherapy benefit, with aPD1 improving EFS only in patients with low baseline levels of Ki67+ Tregs. These findings were further validated in the multicenter phase 3 DIPPER trial (n = 262, NCT03427827) and the phase 3 OAK trial of anti-PD-L1 immunotherapy in NSCLC, underscoring the predictive value of Ki67+ Treg frequency in identifying the beneficiaries of immunotherapy and potentially guiding personalized treatment strategies.

[Mouse bone marrow mesenchymal stem cells co-overexpressing IFN-γ/sPD-1 have high biological activity and genetic stability].

Objective To investigate the effects of lentivirus-mediated overexpression of interferon gamma (IFN-γ) and soluble programmed death 1 (sPD-1) on the biological activity and genetic stability of bone marrow mesenchymal stem cells (BMSCs). Methods BMSCs were isolated and cultured by whole bone marrow adhesion method. The expression of surface markers of BMSCs was identified by flow cytometry. IFN-γ and sPD-1 gene sequences with green fluorescent protein (GFP) and red fluorescent protein (RFP) were amplified, and BMSCs overexpressing IFN-γ, sPD-1, and IFN-γ/sPD-1 were constructed by lentiviral transfection. The cell morphology was observed using an inverted microscope. The mRNA and protein expression of IFN-γ and sPD-1 were detected by real-time fluorescence quantitative PCR and Western blot analysis, respectively. The biological activity of the IFN-γ and sPD-1 overexpression BMSCs was assessed through functional assays, while their genetic stability was analysed using karyotyping. Results BMSCs positive for CD44 and CD105 and negative for CD34, CD11b and CD45 were successfully isolated and cultured. Compared with the empty group, IFN-γ and sPD-1 mRNA expression levels were significantly higher in the combined IFN-γ/sPD-1 group, but the growth of cells was similar in all groups; the telomerase activity was significantly reduced in the IFN-γ group, but the changes in telomerase activity were not obvious in the sPD-1 group and the combined IFN-γ/sPD-1 group. Conclusion BMSCs overexpressing IFN-γ and sPD-1 in combination has high biological activity and genetic stability.

Improved antitumor effectiveness of oncolytic HSV-1 viruses engineered with IL-15/IL-15Rα complex combined with oncolytic HSV-1-aPD1 targets colon cancer.

Oncolytic virotherapy is emerging as a promising therapeutic avenue for cancer treatment, harnessing both innate and tumor-specific immune responses for targeted tumor elimination. In this study, we present a novel oncolytic virus (oHSV1-IL15B) derived from herpes simplex virus-1 (HSV-1), armed with IL-15/IL-15Rα complex, with a focus on treating colon cancer combined with oncolytic HSV-1 expressing anti-PD-1 antibody (oHSV1-aPD1). Results from our study reveal that recombinant oHSV-1 virus equipped with IL-15/IL-15Rα complex exhibited significant anti-tumor effects in a murine CT26 colon adenocarcinoma model. Notably, oHSV1-IL15B combined with oHSV-1-aPD1 demonstrates superior tumor inhibition and prolonged overall survival compared to oHSV1-mock and monotherapy groups. Further exploration highlights the impact of oHSV1-IL15B, oHSV-1-aPD1 and combined group on antitumor capacity, revealing a substantial increase in CD8+ T and CD4+ T cell proportions of CT26-bearing BALB/c mice and promoting apoptosis in tumor tissue. The study emphasizes the pivotal role of cytotoxic CD8+T cells in oncolytic virotherapy, demonstrating that recombinant oHSV1-IL15B combined with oncolytic HSV-1-aPD1 induces a robust tumor-specific T cell response. RNA sequence analysis highlighted oHSV1-IL15B combined with oHSV1-aPD1 improved tumors immune microenvironment on immune response, antiviral response-related genes and apoptosis-related genes, which contributed to anti-tumor immunotherapy. The findings underscore the promising antitumor activity achieved through the combination of IL-15/IL-15Rα complex and anti-PD-1 antibody with oHSV-1. This research opens avenues for diverse therapeutic strategies, suggesting the potential of synergistically utilizing cytokines and anti-PD-1 antibody with oncolytic viruses to enhance immunotherapy for cancer management.

Human papillomavirus-encoded circular RNA circE7 promotes immune evasion in head and neck squamous cell carcinoma.

Immune evasion represents a crucial milestone in the progression of cancer and serves as the theoretical foundation for tumor immunotherapy. In this study, we reveal a negative association between Human Papillomavirus (HPV)-encoded circular RNA, circE7, and the infiltration of CD8+ T cells in head and neck squamous cell carcinoma (HNSCC). Both in vitro and in vivo experiments demonstrate that circE7 suppresses the function and activity of T cells by downregulating the transcription of LGALS9, which encodes the galectin-9 protein. The molecular mechanism involves circE7 binding to acetyl-CoA carboxylase 1 (ACC1), promoting its dephosphorylation and thereby activating ACC1. Activated ACC1 reduces H3K27 acetylation at the LGALS9 gene promoter, leading to decreased galectin-9 expression. Notably, galectin-9 interacts with immune checkpoint molecules TIM-3 and PD-1, inhibiting the secretion of cytotoxic cytokines by T cells and promoting T cell apoptosis. Here, we demonstrate a mechanism by which HPV promotes immune evasion in HNSCC through a circE7-driven epigenetic modification and propose a potential immunotherapy strategy for HNSCC that involves the combined use of anti-PD-1 and anti-TIM-3 inhibitors.

Weitiao No. 3 (3) enhances the efficacy of anti-programmed cell death protein-1 immunotherapy by modulating the intestinal microbiota in an orthotopic model of gastric cancer mice.

OBJECTIVE: To explore the effects of Weitiao No. 3 (3, WD-3) on anti-programmed cell death protein-1 (PD-1) immunotherapy in gastric cancer (GC). METHODS: The intestinal microbiota was analyzed by 16S rDNA sequencing of fecal samples from three groups: healthy people (Health), GC patients (GC), and WD-3-treated GC patients (WD-3). Next, we established an orthotopic model of GC mice, which were treated with anti-PD-1, WD-3, or an inoculation of intestinal bacteria. Immune markers CD3, CD4, CD8, and forkhead box protein P3 (FOXP3), and the cell proliferation marker Ki67, were evaluated by immunohistochemistry. Cell apoptosis in GC tumors was assessed by terminal-deoxynucleotidyl-transferase-mediated deoxyuridine triphosphate nick end labeling staining. Enzyme-linked immunosorbent assays (ELISAs) were performed to analyze the serum levels of the following cytokines in GC mice: tumor necrosis factor (TNF)-α, interleukin (IL)-2, IL-6, IL-10, interferon (IFN)-γ, and transforming growth factor (TGF)-ß. RESULTS: Sequencing data showed that there were significant differences in the composition of the gut microbial community among the three human groups. The gut bacteria in the three groups mainly comprised the phyla Firmicutes, Proteobacteria, Bacteroidetes, and Actinobacteria. At the genus level, the relative abundances of Bifidobacterium and Coprococcus showed significant decreases in the GC group, and an obvious increase in the WD-3 group, compared with the Health group. Interestingly, the relative abundance of Saccharopolyspora was only detected in the WD-3 group. The results of in vivo experiments in GC mice showed that WD-3 or anti-PD-1 treatment increased the levels of CD3+, CD4+, and CD8+ T cells, but decreased the levels of FOXP3+ regulatory T cells. Furthermore, WD-3 or PD-1 antibody treatment inhibited proliferation and promoted apoptosis of GC tumor cells. ELISA analysis showed that WD-3 or PD-1 antibody treatment facilitated TNF-α, IL-2, and IFN-γ expression, while suppressing IL-6, IL-10, and TGF-ß expression. Combination therapy with WD-3 and anti-PD-1 intensified all of these effects. CONCLUSION: WD-3 enhanced the immunotherapeutic efficacy of anti-PD-1 by modulating the intestinal microbiota in an orthotopic model of GC mice.

The mechanism of MMP14-positive tumor-associated fibroblast subsets in inhibiting PD-1 immunotherapy for esophageal cancer through exosomal tsRNA-10522.

Esophageal cancer (EC) continues to pose a significant health risk. Cancer-associated fibroblasts (CAFs), an essential part of the tumor microenvironment (TME), are viewed as potential therapeutic targets. However, their role in tumor mechanisms specific to esophageal cancer remains to be elucidated. This study identified MMP14+ CAFs and MMP14- CAFs using immunofluorescence staining. The cytotoxic activity of CD8 T cells was assessed via western blot and ELISA. Using a transwell test, the migratory potential of MMP14+ CAFs was evaluated. Using flow cytometry, apoptosis was found in the esophageal squamous cell carcinoma cell line KYSE30. To determine the important tsRNAs released by MMP14+ CAFs, tsRNA-seq was used. Two subgroups of EC receiving PD-1 immunotherapy were identified by our research: MMP14+ CAFs and MMP14- CAFs. MMP14+ CAFs showed improved migratory capacity and released more inflammatory factors linked to cancer. Through exosomes, these CAFs may prevent anti-PD-1-treated CD8 T cells from being cytotoxic. Furthermore, exosomal tsRNA from MMP14+ CAFs primarily targeted signaling pathways connected with cancer. Notably, it was discovered that tsRNA-10522 plays a critical role within inhibiting CD8 T cell tumor cell death. The tumor cell killing of CD8 T cells by exosomal tsRNA-10522 is inhibited by a subgroup of cells called MMP14+ CAFs inside the EC microenvironment during PD-1 immunotherapy. This reduces the effectiveness of PD-1 immunotherapy for EC. Our findings demonstrate the inhibitory function of MMP14+ CAFs within EC receiving PD-1 immunotherapy, raising the prospect that MMP14+ CAFs might serve as predictive indicators in EC receiving PD-1 immunotherapy.

A splicing isoform of PD-1 promotes tumor progression as a potential immune checkpoint.

The immune checkpoint receptor, programmed cell death 1 (PD-1, encoded by PDCD1), mediates the immune escape of cancer, but whether PD-1 splicing isoforms contribute to this process is still unclear. Here, we identify an alternative splicing isoform of human PD-1, which carries a 28-base pairs extension retained from 5' region of intron 2 (PD-1^28), is expressed in peripheral T cells and tumor infiltrating lymphocytes. PD-1^28 expression is induced on T cells upon activation and is regulated by an RNA binding protein, TAF15. Functionally, PD-1^28 inhibits T cell proliferation, cytokine production, and tumor cell killing in vitro. In vivo, T cell-specific exogenous expression of PD-1^28 promotes tumor growth in both a syngeneic mouse tumor model and humanized NOG mice inoculated with human lung cancer cells. Our study thus demonstrates that PD-1^28 functions as an immune checkpoint, and may contribute to resistance to immune checkpoint blockade therapy.

Single-cell and spatial transcriptome characterize coinhibitory cell-cell communications during histological progression of lung adenocarcinoma.

Introduction: Lung adenocarcinoma, a prevalent and lethal malignancy globally, is characterized by significant tumor heterogeneity and a complex tumor immune microenvironment during its histologic pattern progression. Understanding the intricate interplay between tumor and immune cells is of paramount importance as it could potentially pave the way for the development of effective therapeutic strategies for lung adenocarcinoma. Methods: In this study, we run comparative analysis of the single-cell transcriptomic data derived from tumor tissues exhibiting four distinct histologic patterns, lepidic, papillary, acinar and solid, in lung adenocarcinoma. Furthermore, we conducted immunofluorescence assay and spatial transcriptomic sequencing to validated the spatial co-localization of typical co-inhibitory factors. Results and Discussion: Our analysis unveiled several co-inhibitory receptor-ligand interactions, including PD1-PDL1, PVR-TIGIT and TIGIT-NECTIN2, that potentially exert a pivotal role in recruiting immunosuppressive cells such as M2 macrophages and Tregs into LUAD tumor, thereby establishing immunosuppressive microenvironment and inducing T cells to exhaustion state. Furthermore, The expression level of these co-inhibitory factors, such as NECTIN2 and PVR, were strongly correlated with low immune infiltration, unfavorable patient clinical outcomes and limited efficacy of immunotherapy. We believe this study provides valuable insights into the heterogeneity of molecular, cellular interactions leading to immunosuppressive microenvironment during the histological progression of lung adenocarcinoma. The findings could facilitate the development of novel immunotherapy for lung cancer.

High PD-1 and CTLA-4 expression correlates with host immune suppression in patients and a mouse model infected with Echinococcus multilocularis.

BACKGROUND: Alveolar echinococcosis (AE), a fatal disease caused by Echinococcus multilocularis, often affects the liver, with tumor-like growth. However, the mechanism by which E. multilocularis evades host immune surveillance remains unclear. METHODS: We collected liver specimens from hepatic alveolar echinococcosis (HAE) patients and established a mouse model of E. multilocularis infection. Immunofluorescence staining and flow cytometry were performed to analyze programmed cell death protein 1 (PD-1) and cytotoxic T lymphocyte associated antigen 4 (CTLA-4) expression in human samples, while flow cytometry and quantitative real-time polymerase chain reaction (PCR) were performed for similar analyses in mouse samples. Cell proliferation and protoscolex (PSC) killing assays were designed to explore how E. multilocularis induces host immunosuppression. RESULTS: An inflammatory reaction band with high PD-1 and CTLA-4 expression was found in close liver tissue (CLT). The ratio of regulatory T cells (Tregs) was higher in CLT than in distant liver tissue (DLT), and Tregs in CLT tended to express higher levels of PD-1 and CTLA-4 than those in DLT from HAE patients. Echinococcus multilocularis-infected mice showed significantly elevated expression of PD-1 and CTLA-4 on splenocytes and peritoneal cells. PD-1/PD-L1 or CTLA-4 pathway blockade could relieve the immunosuppressive effects of Tregs from infected mice and enhance PSC killing by mouse splenocytes. CONCLUSIONS: E. multilocularis regulated the function of T cells via the PD-1/PD-L1- and CTLA-4-dependent pathways and subsequently evaded host immune attacks. These findings provide insights for investigating the pathogenic mechanism of AE.

KLHDC8A Regulates M1/M2 Macrophage Polarization Through the PD-1/STAT3 Pathway to Promote Papillary Thyroid Cancer Development.

BACKGROUND: Papillary thyroid cancer (PTC) is one of the most frequent endocrine malignancies. Kelch domain containing 8A (KLHDC8A) is reported as an epigenetically driven oncogene, but the role of KLHDC8A in PTC is still unclear. This study aimed to explore the function of KLHDC8A in PTC progression. METHODS: KLHDC8A expression was analyzed by the Gene Expression Profiling Interactive Analysis (GEPIA) website, quantitative real-time PCR (qRT-PCR), and western blot. The viability of PTC cells (TPC-1 and BCPAP) was assessed by cell counting kit-8 (CCK-8) kit. A transwell assay was carried out to evaluate the invasion and migration of PTC cells. Macrophage polarization-associated markers were determined by qRT-PCR and western blot. Mice tumor xenograft models were established to analyze the role of KLHDC8A in vivo. Pathway-related proteins (programmed cell death protein 1 (PD-1) and signal transducer and activator of transcription 3 (STAT3)) were determined by western blot. RESULTS: GEPIA demonstrated that KLHDC8A was highly expressed in PTC (p < 0.05). Knockdown of KLHDC8A hindered cell viability, invasion, and migration of PTC cells (p < 0.0001). Additionally, KLHDC8A knockdown inhibited M2 polarization while promoting M1 polarization (p < 0.0001). Meanwhile, KLHDC8A silencing inhibited tumor growth in mice xenografted models (p < 0.0001). Moreover, the PD-1/STAT3 pathway was suppressed by KLHDC8A silencing (p < 0.01), and the STAT3 activator (colivelin) attenuated the inhibitory effects of KLHDC8A silencing on PTC progression (p < 0.01). CONCLUSIONS: Through in vivo and in vitro experiments, KLHDC8A silencing could restrain PTC cell viability, migration, and invasion, inhibit tumor growth, and promote M1 polarization via the PD-1/STAT3 axis, providing a new therapeutic idea for PTC clinical treatment.

Decoding functional impact of epigenetic regulator mutations on ligand-receptor interaction perturbations for evaluation of cancer immunotherapy.

Cellular crosstalk mediated by ligand-receptor interactions largely complicates the tumour ecosystem, resulting in heterogeneous tumour microenvironments that affect immune response and clinical benefits from immunotherapy. Epigenetic mechanisms are pivotal to expression changes of immune-related genes and can modulate the anti-tumour immune response. However, the functional consequences of disrupted epigenetic regulators (ERs) on ligand-receptor interactions in the tumour microenvironment remain largely unexplored. Here, we proposed mutations of ERs in perturbed interactions (MERIN), a molecular network-based approach that incorporates multi-omics data, to infer the potential consequences of ER mutations on ligand-receptor interaction perturbations. Leveraging cancer genomic profiles and molecular interaction data, we comprehensively decoded the functional consequences of ER mutations on dysregulated ligand-receptor interactions across 33 cancers. The dysregulated ligand-receptor genes were indeed enriched in cancer and immune-related function. We demonstrated the potential significance of PD1-PDL1 interaction-related ER mutations in stratifying cancer patients from multiple independent data cohorts. The ER mutation group showed distinct immunological characterizations and prognoses. Furthermore, we highlighted that the ER mutations could potentially predict clinical outcomes of immunotherapy. Our computational and clinical assessment underscore the utility of MERIN for elucidating the functional relevance of ER mutations in cancer immune response, potentially aiding patients' stratification for immunotherapy.

Genetic absence of PD-L1 does not restore CD8+ T cell function during respiratory virus infection and delays virus clearance.

A key mediator of T cell impairment during respiratory virus infection is the inhibitory receptor PD-1. PD-1 is induced on T cells following antigen exposure, whereas proinflammatory cytokines upregulate the ligands PD-L1 and PD-L2. Respiratory virus infection leads to upregulation of PD-L1 on airway epithelial cells, dendritic cells, and alveolar macrophages. However, the role of PD-L1 on different cell types in acute respiratory virus infections is not known. We sought to determine the role of PD-L1 on different cell types in CD8+ T cell impairment. We found that PD-L1-/- mice challenged with human metapneumovirus or influenza showed a similar level of CD8+ T cell impairment compared to wild-type (WT) mice. Moreover, virus clearance was delayed in PD-L1-/- mice compared to WT. CD8+ T cells from PD-L1-deficient mice expressed higher levels of inhibitory receptors both at baseline and after respiratory virus infection. The antibody blockade of PD-L2 failed to restore function to the impaired cells. While reciprocal bone marrow chimeras between WT and PD-L1-/- mice did not restore CD8+ T cell function after the respiratory virus challenge, mice that received the PD-L1-/- bone marrow had higher inhibitory receptor expression on CD8+ cells. This discrepancy in the inhibitory receptor expression suggests that cells of the hematopoietic compartment contribute to T cell impairment on CD8+ T cells.IMPORTANCEThe phenomenon of pulmonary CD8+ T cell impairment with diminished antiviral function occurs during acute respiratory virus infection mediated by Programmed Cell Death-1 (PD-1) signaling. Moreover, PD-1 blockade enhances T cell function to hasten viral clearance. The ligand PD-L1 is expressed in many cell types, but which cells drive lung T cell impairment is not known. We used genetic approaches to determine the contribution of PD-L1 on lung T cell impairment. We found that PD-L2 cannot compensate for the loss of PD-L1, and PD-L1-deficient mice exhibit increased expression of other inhibitory receptors. Bone marrow chimeras between PD-L1-deficient and wild-type mice indicated that hematopoietic PD-L1 expression is associated with inhibitory receptor upregulation and impairment.

Apoptosis Regulation in Dental Pulp Cells and PD-1/PD-L1 Expression Dynamics Under Ozone Exposure - A Pilot Approach.

This study aimed to determine the effect of ozone on the expression of Bax and Bcl-2 genes in dental pulp cells. Additionally, the programmed cell death protein 1, programmed death-ligand 1, and CD200 antigens were determined in lymphocytes to assess their surface expression. Dental pulp cells were cultured from extracted healthy third molars and characterized as dental pulp stromal cells. Gene expression of Bcl-2 and Bax was analyzed at 0 s, 6 s, and 12 s of ozone exposure using real-time PCR. Lymphocytes from dental pulp were subjected to ozone exposure for 12 s and PD-1, PD-L1, and CD200/CD200R expression was analyzed by flow cytometry. Upon exposure to ozone for 6 s, the Bcl-2 expression decreased significantly to -0.09, and at 12 s, it increased significantly to 0.3. Bax gene expression level increased significantly to 0.188 after 6 s exposure, and at 12 s, to 0.16. Lymphocytes exposed to ozone for 12 s showed minimal changes in PD-1, PD-L1, and CD200/CD200R expression levels, indicating that oxidative stress does not impact the signaling pathways regulating these molecules. The significant upregulation of Bcl-2 at 12 s highlights the cells' effort to protect themselves from prolonged oxidative stress, possibly tipping the balance toward cell survival and tissue repair. However, the absence of changes in PD-1 and PD-L1 expression on lymphocytes under oxidative stress suggests that these molecules are not sensitive to oxidative stress in this context.

A multi-task deep learning model based on comprehensive feature integration and self-attention mechanism for predicting response to anti-PD1/PD-L1.

BACKGROUND: Immune checkpoint inhibitor (ICI) has been widely used in the treatment of advanced cancers, but predicting their efficacy remains challenging. Traditional biomarkers are numerous but exhibit heterogeneity within populations. For comprehensively utilizing the ICI-related biomarkers, we aim to conduct multidimensional feature selection and deep learning model construction. METHODS: We used statistical and machine learning methods to map features of different levels to next-generation sequencing gene expression. We integrated genes from different sources into the feature input of a deep learning model, by means of self-attention mechanism. RESULTS: We performed feature selection at the single-cell sequencing level, PD-L1 (CD274) analysis level, tumor mutational burden (TMB)/mismatch repair (MMR) level, and somatic copy number alteration (SCNA) level, obtaining 96 feature genes. Based on the pan-cancer dataset, we trained a multi-task deep learning model. We tested the model in the bladder urothelial carcinoma testing set 1 (AUC = 0.62, n = 298), bladder urothelial carcinoma testing set 2 (AUC = 0.66, n = 89), non-small cell lung cancer testing set (AUC = 0.85, n = 27), and skin cutaneous melanoma testing set (AUC = 0.71, n = 27). CONCLUSION: Our study demonstrates the potential of the deep learning model for integrating multidimensional features in predicting the outcome of ICI. Our study also provides a potential methodological case for medical scenarios requiring the integration of multiple levels of features.

Mechanical force regulates ligand binding and function of PD-1.

Despite the success of PD-1 blockade in cancer therapy, how PD-1 initiates signaling remains unclear. Soluble PD-L1 is found in patient sera and can bind PD-1 but fails to suppress T cell function. Here, we show that PD-1 function is reduced when mechanical support on ligand is removed. Mechanistically, cells exert forces to PD-1 and prolong bond lifetime at forces <7 pN (catch bond) while accelerate dissociation at forces >8pN (slip bond). Molecular dynamics of PD-1-PD-L2 complex suggests force may cause relative rotation and translation between the two molecules yielding distinct atomic contacts not observed in the crystal structure. Compared to wild-type, PD-1 mutants targeting the force-induced distinct interactions maintain the same binding affinity but suppressed/eliminated catch bond, lowered rupture force, and reduced inhibitory function. Our results uncover a mechanism for cells to probe the mechanical support of PD-1-PD-Ligand bonds using endogenous forces to regulate PD-1 signaling.

Dissecting transcriptome signals of anti-PD-1 response in lung adenocarcinoma.

Immune checkpoint blockades are actively adopted in diverse cancer types including metastatic melanoma and lung cancer. Despite of durable response in 20-30% of patients, we still lack molecular markers that could predict the patient responses reliably before treatment. Here we present a composite model for predicting anti-PD-1 response based on tumor mutation burden (TMB) and transcriptome sequencing data of 85 lung adenocarcinoma (LUAD) patients who received anti-PD-(L)1 treatment. We found that TMB was a good predictor (AUC = 0.81) for PD-L1 negative patients (n = 20). For PD-L1 positive patients (n = 65), we built an ensemble model of 100 XGBoost learning machines where gene expression, gene set activities and cell type composition were used as input features. The transcriptome-based models showed excellent accuracy (AUC > 0.9) and highlighted the contribution of T cell activities. Importantly, nonresponder patients with high prediction score turned out to have high CTLA4 expression, which suggested that neoadjuvant CTLA4 combination therapy might be effective for these patients. Our data and analysis results provide valuable insights into developing biomarkers and strategies for treating LUAD patients using immune checkpoint inhibitors.

A Combined Proteomic and Transcriptomic Signature Is Predictive of Response to Anti-PD-1 Treatment: A Retrospective Study in Metastatic Melanoma Patients.

Resistance biomarkers are needed to identify patients with advanced melanoma obtaining a response to ICI treatment and developing resistance later. We searched a combination of molecular signatures of response to ICIs in patients with metastatic melanoma. In a retrospective study on patients with metastatic melanoma treated with an anti-PD-1 agent carried out at Istituto Nazionale Tumori-IRCCS-Fondazione "G. Pascale", Naples, Italy. We integrated a whole proteome profiling of metastatic tissue with targeted transcriptomics. To assess the prognosis of patients according to groups of low and high risk, we used PFS and OS as outcomes. To identify the proteins and mRNAs gene signatures associated with the patient's response groups, the discriminant analysis for sparse data performed via partial least squares procedure was performed. Tissue samples from 22 patients were analyzed. A combined protein and gene signature associated with poorer response to ICI immunotherapy in terms of PFS and OS was identified. The PFS and OS Kaplan-Meier curves were significantly better for patients with high expression of the protein signature compared to patients with low expression of the protein signature and who were high-risk (Protein: HR = 0.023, 95% CI: 0.003-0.213; p < 0.0001. Gene: HR = 0.053, 95% CI: 0.011-0.260; p < 0.0001). The Kaplan-Meier curves showed that patients with low-risk gene signatures had better PFS (HR = 0 0.221, 95% CI: 0.071-0.68; p = 0.007) and OS (HR = 0.186, 95% CI: 0.05-0.695; p = 0.005). The proteomic and transcriptomic combined analysis was significantly associated with the outcomes of the anti-PD-1 treatment with a better predictive value compared to a single signature. All the patients with low expression of protein and gene signatures had progression within 6 months of treatment (median PFS = 3 months, 95% CI: 2-3), with a significant difference vs. the low-risk group (median PFS = not reached; p < 0.0001), and significantly poorer survival (OS = 9 months, 95% CI: 5-9) compared to patients with high expression of protein and gene signatures (median OS = not reached; p < 0.0001). We propose a combined proteomic and transcriptomic signature, including genes involved in pro-tumorigenic pathways, thereby identifying patients with reduced probability of response to immunotherapy with ICIs for metastatic melanoma.

Clinical characteristics and influencing factors of anti-PD-1/PD-L1-related severe cardiac adverse event: based on FAERS and TCGA databases.

Combining the FDA Adverse Event Reporting System (FAERS) and the Cancer Genome Atlas (TCGA) databases, we aim to explore the factors that influence anti-programmed cell death protein-1 inhibitors/programmed death-ligand-1 (PD-1/PD-L1) related severe cardiac adverse events (cAEs). We obtained anti-PD-1/PD-L1 adverse event reports from January 2014 to December 2022 from the FAERS database. Disproportionality analysis was performed to find anti-PD-1/PD-L1-related cAEs using the proportional reporting ratio (PRR). We were exploring influencing factors based on multivariate logistic regression analysis. Finally, we utilized a strategy that combines FAERS and TCGA databases to explore the potential immune and genetic influencing factors associated with anti-PD-1/PD-L1-related severe cAEs. Reports of severe cAEs accounted for 7.10% of the overall anti-PD-1/PD-L1 adverse event reports in the FAERS database. Immune-mediated myocarditis (PRR = 77.01[59.77-99.23]) shows the strongest toxic signal. The elderly group (65-74: OR = 1.34[1.23-1.47], ≥ 75: OR = 1.64[1.49-1.81]), male (OR = 1.14[1.05-1.24]), anti-PD-L1 agents (OR = 1.17[1.03-1.33]), patients with other adverse events (OR = 2.38[2.17-2.60]), and the concomitant use of proton pump inhibitor (OR = 1.29[1.17-1.43]), nonsteroidal anti-inflammatory drugs (OR = 1.17[1.04-1.31]), or antibiotics (OR = 1.24[1.08-1.43]) may increase the risk of severe cAEs. In addition, PD-L1 mRNA (Rs = 0.71, FDR = 2.30 × 10- 3) and low-density lipoprotein receptor-related protein 3 (LRP3) (Rs = 0.82, FDR = 2.17 × 10- 2) may be immune and genetic influencing factors for severe cAEs. Severe cAEs may be related to antigen receptor-mediated signalling pathways. In this study, we found that age, gender, anti-PD-1/PD-L1 agents, concomitant other adverse events, concomitant medication, PD-L1 mRNA, and LRP3 may be influencing factors for anti-PD-1/PD-L1-related severe cAEs. However, our findings still require a large-scale prospective cohort validation.