Lymphocyte Activation Gene-3 Research Articles

A phase 3 trial of fixed dose combinations of fianlimab (anti–LAG-3) + cemiplimab (anti–PD-1) versus relatlimab + nivolumab in patients with unresectable or metastatic melanoma.

TPS9611 Background: Fianlimab (anti–lymphocyte activation gene 3 [LAG-3]) and cemiplimab (anti–programmed cell death-1 [PD-1]) are high-affinity, fully human, immunoglobulin G4 monoclonal antibodies. Concurrent LAG-3 blockade may enhance the efficacy of anti–PD-1 therapies. Relatlimab (anti–LAG-3) + nivolumab (anti–PD-1) monoclonal antibodies demonstrated benefit in progression-free survival (PFS) in advanced melanoma (Mel) patients compared with nivolumab alone in the RELATIVITY-047 study. In a multicohort Phase 1 study (NCT03005782), fianlimab + cemiplimab demonstrated reproducibly high clinical activity (objective response rate [ORR]: 61%, N=98) in three independent cohorts of advanced PD-(L)1–naïve metastatic Mel patients with an acceptable safety profile. Methods: This is a randomized, open-label, multicenter Phase 3 study (NCT06246916) comparing the fixed dose combination (FDC) of fianlimab + cemiplimab to the FDC of relatlimab + nivolumab in patients with unresectable or metastatic Mel. The primary objective is to demonstrate superiority of fianlimab + cemiplimab compared with relatlimab + nivolumab as measured by ORR assessed by blinded independent central review (BICR). This study will be conducted at approximately 80 sites across North America. Key inclusion criteria are: (1) aged ≥18 years; (2) histologically confirmed unresectable stage III or IV (metastatic) Mel; (3) no prior systemic therapy for unresectable or metastatic Mel; patients with adjuvant and/or neoadjuvant systemic therapies are eligible with a treatment-free and disease-free interval of >6 months; (4) measurable disease per Response Evaluation Criteria in Solid Tumors version 1.1; (5) Eastern Cooperative Oncology Group performance status of ≤1; (6) adequate bone marrow, hepatic, and kidney function. Approximately 560 patients will be randomized in a 1:1 ratio to two treatment arms: Arm A: FDC of fianlimab (Dose 1) + cemiplimab (Dose 2) every 3 weeks intravenously (IV); Arm B: FDC of relatlimab 160 mg + nivolumab 480 mg every 4 weeks IV. All patients will be stratified based on metastatic stage (stage III vs M1a–b vs M1c–d), baseline lactate dehydrogenase level (≤ vs > upper limit of normal), and prior adjuvant and/or neoadjuvant systemic therapy. Patients will receive treatment until disease progression, unacceptable toxicity, withdrawal of consent, a study withdrawal criterion is met, or the sponsor terminates the study. The primary endpoint is ORR and key secondary endpoints are PFS and overall survival. Additional secondary endpoints are duration of response, disease control rate, investigator-assessed ORR and PFS, safety, pharmacokinetics, and immunogenicity. Clinical trial information: NCT06246916 .

A phase 2/3 study of fianlimab, cemiplimab, plus chemotherapy versus cemiplimab plus chemotherapy in first-line treatment of advanced non-small cell lung cancer.

TPS8660 Background: Non-small cell lung cancer (NSCLC) is the most common type of lung cancer. Anti–programmed cell death-1 (PD-1) therapies have improved outcomes in patients with NSCLC; however, most patients do not respond or only respond for a limited time. The combination of cemiplimab (anti–PD-1) and chemotherapy has been studied for the first-line treatment of advanced NSCLC (aNSCLC), regardless of programmed cell death-ligand 1 (PD-L1) status. While the standard of care continues to evolve for NSCLC, one approach to potentially improve outcomes is the combination of checkpoint inhibitors (IO) with chemotherapy. Fianlimab (anti–lymphocyte activation gene 3 [LAG-3]) and cemiplimab are both high-affinity, fully human IgG4 monoclonal antibody IO therapies that have shown promising clinical activity when combined in patients with aNSCLC in a Phase 1 study (NCT03005782). This ongoing study will further investigate the combination of fianlimab + cemiplimab + chemotherapy. Methods: This is a randomized, multicenter, Phase 2/3 study of fianlimab + cemiplimab + platinum-doublet chemotherapy (chemo) versus cemiplimab + chemo in patients with unresectable stage IIIB/IIIC or stage IV NSCLC irrespective of PD-L1 expression levels (NCT05800015). This study will be conducted globally at approximately 210 sites. Patient eligibility criteria: ≥18 years old; squamous or non-squamous histology with stage IIIB, IIIC, or IV disease; valid PD-L1 result; ≥1 radiographically measurable lesion by computed tomography/magnetic resonance imaging; Eastern Cooperative Oncology Group performance status ≤1; adequate organ and bone marrow function. The Phase 2 portion will be used to determine the fianlimab dose selected for the Phase 3 portion: patients will be randomized 1:1:1 to receive fianlimab high dose + cemiplimab 350 mg + chemo (Arm A), fianlimab low dose + cemiplimab 350 mg + chemo (Arm B), or cemiplimab 350 mg + chemo + placebo (Arm C), Q3W IV. In Phase 3, patients will be randomized 1:1 into one of two treatment arms (either Arm A or Arm B, and Arm C) based on findings from Phase 2. The primary endpoint of Phase 2 is objective response rate (ORR) per blinded independent central review. The primary endpoint of Phase 3 is overall survival. The secondary endpoints include efficacy (ORR, disease control rate, time to tumor response, duration of response, progression-free survival, and overall survival), safety and tolerability, immunogenicity (anti-drug antibodies and neutralizing antibodies against fianlimab or cemiplimab in serum), patient-reported outcomes, and pharmacokinetics. This study and a parallel study of fianlimab + cemiplimab in patients with aNSCLC with tumors expressing PD-L1 ≥50% (NCT05785767) are currently open for enrollment. Clinical trial information: NCT05800015 .

A phase 2/3 study of fianlimab plus cemiplimab versus cemiplimab in patients with advanced non-small cell lung cancer with tumors expressing PD-L1 ≥50%.

TPS8663 Background: Fianlimab (anti–lymphocyte activation gene 3 [LAG-3]) and cemiplimab (anti–programmed cell death-1 [PD-1]) are high-affinity, fully human, IgG4 monoclonal antibodies. In patients (pts) with advanced non-small cell lung cancer (aNSCLC) and programmed cell death-ligand 1 (PD-L1) expression ≥50% with no actionable mutations, first-line cemiplimab monotherapy showed significantly prolonged overall survival (OS) and progression-free survival (PFS) versus chemotherapy, with a safety profile consistent with previous reports for cemiplimab monotherapy. Despite pts’ selection by PD-L1 expression, only ~50% of pts respond to PD-1 therapy, thus there is a need for immune-oncology combinations like anti–LAG-3 plus anti–PD-1 to potentially improve outcomes. Methods: This is a randomized, double-blind, Phase 2/3 study (NCT05785767) to evaluate fianlimab + cemiplimab versus cemiplimab monotherapy as first-line treatment in pts with aNSCLC and tumors expressing PD-L1 ≥50%. The study will be conducted globally at ~210 sites. Key inclusion criteria: ≥18 years old; histologically confirmed squamous or non-squamous stage IIIB/C (not candidates for surgical resection or definitive chemoradiation) or stage IV NSCLC (no prior systemic treatment for recurrent or metastatic NSCLC); PD-L1 expression in ≥50% of tumor cells; ≥1 radiographically measurable lesion per Response Evaluation Criteria in Solid Tumors v1.1; Eastern Cooperative Oncology Group performance status ≤1; adequate organ and bone marrow function. This study has Phase 2 and Phase 3 parts and is expected to enroll ~850 pts. Pts will be treated for up to 108 weeks. In Phase 2, 150 patients will be randomized 1:1:1 into three treatment arms (Q3W IV): Arm A, fianlimab high dose + cemiplimab 350 mg; Arm B, fianlimab low dose + cemiplimab 350 mg; Arm C, cemiplimab 350 mg + saline/dextrose placebo. Based on findings from Phase 2, the dose of fianlimab (low or high) will be selected for Phase 3. In Phase 3, 700 patients will be randomized 1:1 into either experimental Arm A or B, and comparator Arm C (cemiplimab + placebo). In Phase 2, the primary endpoint is objective response rate (ORR) per blinded independent central review (BICR). The secondary endpoints are safety, ORR per investigator assessment, disease control rate (DCR), time to tumor response (TTR), duration of response (DOR), PFS, OS, patient-reported outcomes, pharmacokinetics, and immunogenicity. In Phase 3, the primary endpoint is OS in patients receiving fianlimab + cemiplimab versus cemiplimab monotherapy. Secondary endpoints are safety, ORR, DCR, TTR, DOR, and PFS, per BICR and investigator assessment, patient-reported outcomes, pharmacokinetics, and immunogenicity. This study is open for enrollment along with a second study of fianlimab + cemiplimab + chemotherapy in aNSCLC. Clinical trial information: NCT05785767 .

Nivolumab plus relatlimab in patients with previously treated microsatellite instability-high/mismatch repair-deficient metastatic colorectal cancer: the phase II CheckMate 142 study

BackgroundProgrammed death-1 (PD-1) inhibitors, including nivolumab, have demonstrated long-term survival benefit in previously treated patients with microsatellite instability-high/mismatch repair-deficient (MSI-H/dMMR) metastatic colorectal cancer (CRC). PD-1 and lymphocyte-activation gene 3 (LAG-3)...

Aplp1 interacts with Lag3 to facilitate transmission of pathologic α-synuclein

Pathologic α-synuclein (α-syn) spreads from cell-to-cell, in part, through binding to the lymphocyte-activation gene 3 (Lag3). Here we report that amyloid β precursor-like protein 1 (Aplp1) interacts with Lag3 that facilitates the binding, internalization, transmission, and toxicity of pathologic α-syn. Deletion of both Aplp1 and Lag3 eliminates the loss of dopaminergic neurons and the accompanying behavioral deficits induced by α-syn preformed fibrils (PFF). Anti-Lag3 prevents the internalization of α-syn PFF by disrupting the interaction of Aplp1 and Lag3, and blocks the neurodegeneration induced by α-syn PFF in vivo. The identification of Aplp1 and the interplay with Lag3 for α-syn PFF induced pathology deepens our insight about molecular mechanisms of cell-to-cell transmission of pathologic α-syn and provides additional targets for therapeutic strategies aimed at preventing neurodegeneration in Parkinson’s disease and related α-synucleinopathies.

Progesterone receptor impairs immune respond and down-regulates sensitivity to anti-LAG3 in breast cancer

BackgroundProgesterone receptor (PR) serves as a crucial prognostic and predictive marker in breast cancer. Nonetheless, the interplay between PR and the tumor immune microenvironment remains inadequately understood. This investigation employs bioinformatics analyses, mouse models, and clinical specimens to elucidate the impact of PR on immune microenvironment and identify potential targets for immunotherapy, furnishing valuable guidance for clinical practice. MethodsAnalysis of immune infiltration score by Xcell between PR-positive and PR-negative breast cancer tumors. Construction of overexpression mouse progesterone receptor (mPgr) EMT-6 cell was to explore the tumor immune microenvironment. Furthermore, anti- Lymphocyte-activation gene 3 (LAG3) therapy aimed to investigate whether PR could influence the effectiveness of immune treatments. ResultsOverexpression mPgr inhibited tumor growth in vitro, but promoted tumor growth in Balb/c mouse. Flow cytometry showed that the proportion and cytotoxicity of CD8+T cells in tumor of overexpressing mPgr group were significantly reduced. The significant reduction in overexpressing mPgr group was found in the proportions of LAG3+CD8+ T cells and LAG3+ Treg T cells. Anti-LAG3 treatment resulted in reduced tumor growth in EV group mouse rather than in overexpressing mPgr group. Patents derived tumor fragment (PDTF) also showed higher anti-tumor ability of CD3+T cell in patents’ tumor with PR <20% after anti-human LAG3 treatment in vitro. ConclusionsThe mPgr promotes tumor growth by downregulating the infiltration and function of cytotoxic cell. LAG3 may be a target of ER-positive breast cancer immunotherapy. The high expression of PR hinders the sensitivity to anti-LAG3 treatment.

Immune checkpoint inhibitors: breakthroughs in cancer treatment.

Over the past two decades, immunotherapies have increasingly been considered as first-line treatments for most cancers. One such treatment is immune checkpoint blockade (ICB), which has demonstrated promising results against various solid tumors in clinical trials. Monoclonal antibodies (mAbs) are currently available as immune checkpoint inhibitors (ICIs). These ICIs target specific immune checkpoints, including cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) and programmed cell death protein 1 (PD-1). Clinical trial results strongly support the feasibility of this immunotherapeutic approach. However, a substantial proportion of patients with cancer develop resistance or tolerance to treatment, owing to tumor immune evasion mechanisms that counteract the host immune response. Consequently, substantial research focus has been aimed at identifying additional ICIs or synergistic inhibitory receptors to enhance the effectiveness of anti-PD-1, anti-programmed cell death ligand 1 (anti-PD-L1), and anti-CTLA-4 treatments. Recently, several immune checkpoint molecular targets have been identified, such as T cell immunoreceptor with Ig and ITIM domains (TIGIT), mucin domain containing-3 (TIM-3), lymphocyte activation gene-3 (LAG-3), V-domain immunoglobulin suppressor of T cell activation (VISTA), B and T lymphocyte attenuator (BTLA), and signal-regulatory protein α (SIRPα). Functional mAbs targeting these molecules are under development. CTLA-4, PD-1/PD-L1, and other recently discovered immune checkpoint proteins with distinct structures are at the forefront of research. This review discusses these structures, as well as clinical progress in mAbs targeting these immune checkpoint molecules and their potential applications.

Hepatocyte-derived FGL1 accelerates liver metastasis and tumor growth by inhibiting CD8+ T and NK cells.

Fibrinogen-like protein 1 (FGL1) contributes to the proliferation and metabolism of hepatocytes; however, as a major ligand of the immune checkpoint, its role in the liver regional immune microenvironment is poorly understood. Hepatocytes specifically and highly expressed FGL1 under normal physiological conditions. Increases in hepatic CD8+ T and NK cell numbers and functions were found in Fgl1-deficient (Fgl1-/-) mice, but not in the spleen or lymph node, similar to findings in anti-FGL1 mAb-treated wild-type mice. Furthermore, Fgl1 deficiency or anti-FGL1 mAb blockade restrained liver metastasis and slowed the growth of orthotopic tumors, with significantly prolonged survival of tumor-bearing mice. Tumor-infiltrating hepatic CD8+ T and NK cells upregulated the expression of lymphocyte activation gene-3 (LAG-3) and exhibited stronger antitumor activities after anti-FGL1 treatment. The antitumor efficacy of FGL1 blockade depended on cytotoxic T lymphocytes and NK cells, demonstrated by using a cell-deficient mouse model and cell transfer in vivo. In vitro, FGL1 directly inhibited hepatic T and NK cells related to the receptor LAG-3. In conclusion, hepatocyte-derived FGL1 played critical immunoregulatory roles in the liver and contributed to liver metastasis and tumor growth by inhibiting CD8+ T and NK cell functions via the receptor LAG-3, providing a new strategy for liver cancer immunotherapy.

Cutting Edge: LAG3 Dimerization Is Required for TCR/CD3 Interaction and Inhibition of Antitumor Immunity.

Lymphocyte activation gene 3 (LAG3) is an inhibitory receptor that plays a critical role in controlling T cell tolerance and autoimmunity and is a major immunotherapeutic target. LAG3 is expressed on the cell surface as a homodimer but the functional relevance of this is unknown. In this study, we show that the association between the TCR/CD3 complex and a murine LAG3 mutant that cannot dimerize is perturbed in CD8+ T cells. We also show that LAG3 dimerization is required for optimal inhibitory function in a B16-gp100 tumor model. Finally, we demonstrate that a therapeutic LAG3 Ab, C9B7W, which does not block LAG3 interaction with its cognate ligand MHC class II, disrupts LAG3 dimerization and its association with the TCR/CD3 complex. These studies highlight the functional importance of LAG3 dimerization and offer additional approaches to therapeutically target LAG3.

O05 Single-cell transcriptomic signature of paradoxical eczema in patients with psoriasis treated with biologics

Abstract Introduction and aims Biologics targeting the tumour necrosis factor (TNF) and the interleukin (IL)-17/23 axis are highly effective treatments for psoriasis but can result in cutaneous adverse events. The pathogenesis of paradoxical eczema, an atopic dermatitis (AD) phenotype occurring after biologic initiation in people with psoriasis, is unknown. This study explored the systemic disease signature of paradoxical eczema. Methods We used single-cell RNA-Seq on peripheral blood mononuclear cells (PBMCs) from three patients with psoriasis with paradoxical eczema, and three matched, biologic-treated controls who had psoriasis. Differential gene expression, gene network expression and cell–cell interaction (using MultiNicheNet) analyses allowed comparison of cases and controls. We assessed overlap between paradoxical eczema and AD using six AD transcriptome datasets. Results Overall, 32 827 PBMCs (14 521 from cases, 18 306 from controls) were included and categorized into 27 clusters. Between cases and controls, there were 727 differentially expressed genes (DEGs) (log fold-change &amp;gt; 0.25, adjusted P &amp;lt; 0.05). A total of 94 of the top 100 DEGs were from monocytes. Significant DEG networks (P &amp;lt; 0.05) mostly mapped to T-cell and monocyte clusters, with commonly enriched pathways in cases including interferon (IFN)-γ, IFN-α, TNF, IL-2/signal transducer and activator of transcription 5 and T-cell differentiation pathways. Cell–cell interaction analysis revealed that the most prioritized interactions in controls, based on differential expression data and known ligand-receptor interactions, included immune regulatory interactions (including ligands such as transforming growth factor β1 and lymphocyte-activation gene 3). In cases, functions of prioritized interactions included chemotaxis, leucocyte activation, T-cell priming and IFN-γ signalling. There was significant enrichment of concordance in the direction of effect of DEGs (65%, P = 5.39 × 10−6) and enriched pathways (85%, P = 3.62 × 10−13) between AD and paradoxical eczema. Conclusions Patients with paradoxical eczema have reduced immune regulatory mechanisms and evidence of monocyte and T-cell activation systemically, with increased production IFN-γ, IFN-α and TNF. There is a significant overlap with the AD transcriptome.

Valrubicin-loaded immunoliposomes for specific vesicle-mediated cell death in the treatment of hematological cancers

We created valrubicin-loaded immunoliposomes (Val-ILs) using the antitumor prodrug valrubicin, a hydrophobic analog of daunorubicin. Being lipophilic, valrubicin readily incorporated Val-lLs that were loaded with specific antibodies. Val-ILs injected intravenously rapidly reached the bone marrow and spleen, indicating their potential to effectively target cancer cells in these areas. Following the transplantation of human pediatric B-cell acute lymphoblastic leukemia (B-ALL), T-cell acute lymphoblastic leukemia (T-ALL), or acute myeloid leukemia (AML) in immunodeficient NSG mice, we generated patient-derived xenograft (PDX) models, which were treated with Val-ILs loaded with antibodies to target CD19, CD7 or CD33. Only a small amount of valrubicin incorporated into Val-ILs was needed to induce leukemia cell death in vivo, suggesting that this approach could be used to efficiently treat acute leukemia cells. We also demonstrated that Val-ILs could reduce the risk of contamination of CD34+ hematopoietic stem cells by acute leukemia cells during autologous peripheral blood stem cell transplantation, which is a significant advantage for clinical applications. Using EL4 lymphoma cells on immunocompetent C57BL/6 mice, we also highlighted the potential of Val-ILs to target immunosuppressive cell populations in the spleen, which could be valuable in impairing cancer cell expansion, particularly in lymphoma cases. The most efficient Val-ILs were found to be those loaded with CD11b or CD223 antibodies, which, respectively, target the myeloid-derived suppressor cells (MDSC) or the lymphocyte-activation gene 3 (LAG-3 or CD223) on T4 lymphocytes. This study provides a promising preclinical demonstration of the effectiveness and ease of preparation of Val-ILs as a novel nanoparticle technology. In the context of hematological cancers, Val-ILs have the potential to be used as a precise and effective therapy based on targeted vesicle-mediated cell death.

First-Line Nivolumab and Relatlimab Plus Chemotherapy for Gastric or Gastroesophageal Junction Adenocarcinoma: The Phase II RELATIVITY-060 Study.

Open-label phase II study (RELATIVITY-060) to investigate the efficacy and safety of first-line nivolumab, a PD-1-blocking antibody, plus relatlimab, a lymphocyte-activation gene 3 (LAG-3)-blocking antibody, plus chemotherapy in patients with previously untreated advanced gastric cancer (GC) or gastroesophageal junction cancer (GEJC). Patients with unresectable, locally advanced or metastatic GC/GEJC were randomly assigned 1:1 to nivolumab + relatlimab (fixed-dose combination) + chemotherapy or nivolumab + chemotherapy. The primary end point was objective response rate (ORR; per RECIST v1.1 by blinded independent central review [BICR]) in patients whose tumors had LAG-3 expression ≥1%. Of 274 patients, 138 were randomly assigned to nivolumab + relatlimab + chemotherapy and 136 to nivolumab + chemotherapy. Median follow-up was 11.9 months. In patients with LAG-3 expression ≥1%, BICR-assessed ORR (95% CI) was 48% (38 to 59) in the nivolumab + relatlimab + chemotherapy arm and 61% (51 to 71) in the nivolumab + chemotherapy arm; median progression-free survival (95% CI) by BICR was 7.0 months (5.8 to 8.4) versus 8.3 months (6.9 to 12.1; hazard ratio [HR], 1.41 [95% CI, 0.97 to 2.05]), and median overall survival (95% CI) was 13.5 months (11.9 to 19.1) versus 16.0 months (10.9 to not estimable; HR, 1.04 [95% CI, 0.70 to 1.54]), respectively. Grade 3 or 4 treatment-related adverse events (TRAEs) occurred in 69% and 61% of all treated patients, and 42% and 36% of patients discontinued because of any-grade TRAEs in the nivolumab + relatlimab + chemotherapy and nivolumab + chemotherapy arms, respectively. RELATIVITY-060 did not meet its primary end point of improved ORR in patients with LAG-3 expression ≥1% when relatlimab was added to nivolumab + chemotherapy compared with nivolumab + chemotherapy. Further studies are needed to address whether adding anti-LAG-3 to anti-PD-1 plus chemotherapy can benefit specific GC/GEJC patient subgroups.

LAG-3 : recent developments in combinational therapies in cancer.

The study of anticancer immune responses and in particular the action of immune checkpoint inhibitors that overcome T cell inhibition has revolutionized metastatic patients' care. Unfortunately, many patients are resistant to these innovative immunotherapies. Over the last decade, several immune checkpoint inhibitors, currently available in the clinic, have been developed, such as anti-PD-1/PD-L1 or anti-CTLA-4. More recently, other immune checkpoints have been characterized, among them lymphocyte activation gene 3 (LAG-3). LAG-3 has been the subject of numerous therapeutic studies and may be involved in cancer-associated immune resistance phenomena. This review summarizes the latest knowledge on LAG-3 as an immunotherapeutic target, particularly in combination with standard or innovative therapies. Indeed, many studies are looking at combining LAG-3 inhibitors with chemotherapeutic, immunotherapeutic, radiotherapeutic treatments, or adoptive cell therapies to potentiate their antitumor effects and/or to overcome patients' resistance. We will particularly focus on the association therapies that are currently in phase III clinical trials and innovative combinations in preclinical phase. These new discoveries highlight the possibility of developing other types of therapeutic combinations currently unavailable in the clinic, which could broaden the therapeutic spectrum of personalized medicine.

Chronic intermittent hypoxia alters CD8+ expression in the bone marrow of C57BL/6 mice

Cytotoxic CD8+ cells are critical in anticancer immune response and have become prevalent in immunotherapies over the past decade. Anti-LAG3/anti-PD1 combined immunotherapies increase the number of CD8+ cells. Moderate to severe sleep apnea increases the risk of cancer-related mortality. Chronic intermittent hypoxia, a feature of sleep apnea, decreases the percentage of perforin-expressing CD8+ cells, impairing cytotoxicity. Our objective is to determine the distribution of Prf1(perforin), LAG3(lymphocyte-activation gene 3), and PDCD1(programmed cell death 1) in C57BL/6 mice exposed to chronic intermittent hypoxia (CIH). We hypothesize that Prf1, PDCD1, and LAG3 will be expressed on three discrete clusters with a higher expression of LAG3 and PDCD1 and lower expression of Prf1 between C57BL/6 mice exposed to chronic intermittent hypoxia and normoxia. Bone marrow from the femur of C57BL/6 mice exposed to chronic intermittent hypoxia or normoxia was harvested. Bone marrow mononuclear cells were isolated, RNA was extracted, and single-cell RNA sequencing was performed. Loupe browser was used to re-cluster and quantify expression for genes of interest. Prf1 and PDCD1 are expressed in CD3+CD8−CD4− cluster and LAG3 is expressed in CD3−CD8+CD4+ cluster. LAG3 and Prf1 are present among the top ten genes, while PDCD1 is not in those clusters. Further analysis of the top ten genes of CD3+CD8−CD4− has demonstrated they are a group of natural killer cells. Contradictory to our expectation, Prf1 and PDCD1 are present in CD3+CD8−CD4− cluster while LAG3 is present in CD3−CD8+CD4+ cluster. Further analysis is necessary to determine the underlying mechanisms causing these changes. 5R01CA244271-02. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Shedding light on the role of LAG-3 in hepatocellular carcinoma: unraveling immunomodulatory pathways

Hepatocellular carcinoma (HCC) stands as a primary malignant liver tumor characterized by chronic inflammation and complex alterations within the tumor microenvironment (TME). Lymphocyte activation gene 3 (LAG-3), also known as CD223, has gained prominence as a potential next-generation immune checkpoint, maintaining continuous expression in response to persistent antigen exposure within the TME, warranting our attention. In patients with HCC, LAG-3 expression on T cells, regulatory T cells (Tregs), and natural killer (NK) cells contributes to immune evasion, while high expression of LAG-3 leads to increased angiogenesis and poor prognosis. By interacting with major histocompatibility complex class II molecules, LAG-3 promotes T cell exhaustion and suppresses antitumor responses, often in collaboration with other immune checkpoints like programmed cell death protein 1 (PD-1), while on Tregs and NK cells, LAG-3 modulates their suppressive functions, indirectly facilitating tumor immune escape. LAG-3 expression may offer prognostic insights, correlating with disease progression and outcomes in HCC patients, while various preclinical studies highlight the potential of LAG-3-targeted therapies in reinvigorating immune responses against HCC, with a few combination approaches targeting LAG-3 alongside other checkpoints demonstrating synergistic effects in restoring T cell function. Therefore, harnessing LAG-3 as a therapeutic target holds promise for enhancing antitumor immunity and potentially improving HCC treatment outcomes. Our narrative review aims to delve into the full spectrum of LAG-3 signaling in HCC, with the goal of a better understanding of the pathophysiological and immunological basis of its use to arrest HCC growth and development.

Association of Polymorphisms in PD-1 and LAG-3 Genes with Acute Myeloid Leukemia.

Background and objectives: Acute myeloid leukemia (AML) is a hematological malignancy characterized by uncontrolled proliferation of immature myeloid cells. Immune checkpoint molecules such as programmed cell death protein 1 (PD-1) and lymphocyte activation gene-3 (LAG-3) are essential for controlling anti-tumor immune responses. This study aims to explore the correlation between specific genetic variations (SNPs) in the PDCD1 (rs2227981) and LAG3 (rs12313899) genes and the likelihood of developing AML in the Saudi population. Material and methods: total of 98 Saudi AML patients and 131 healthy controls were genotyped for the PDCD1 rs2227981 and LAG3 rs12313899 polymorphisms using TaqMan genotyping assays. A logistic regression analysis was conducted to evaluate the relationship between the SNPs and AML risk using several genetic models. Results: The results revealed a significant association between the PDCD1 rs2227981 polymorphism and increased AML risk. In AML patients, the frequency of the G allele was considerably greater than in healthy controls (OR = 1.93, 95% CI: 1.31-2.81, p = 0.00080). The GG and AG genotypes were associated with a very high risk of developing AML (p < 0.0001). In contrast, no significant association was observed between the LAG3 rs12313899 polymorphism and AML risk in the studied population. In silico analysis of gene expression profiles from public databases suggested the potential impact of PDCD1 expression levels on the overall survival of AML patients. Conclusions: This study provides evidence for the association of the PDCD1 rs2227981 polymorphism with an increased risk for AML in the Saudi population.

Immunological alterations in patients with current and lifetime suicide ideation and attempts: Examining the relationship with depressive symptoms

BackgroundSuicidal ideation and attempt (SI/SA) have been associated with dysregulation of the immune response and inflammation. However, few studies have explored how innate and acquired cellular immunity impact on the peripheral immune response. Our study addresses this gap by examining the composition of peripheral immune cells and humoral markers among individuals with current SI/SA, individuals with a history of SI/SA, and healthy controls (HC). Additionally, we aim to explore whether depressive symptoms settle the relationship between inflammation and SI/SA. MethodsThis is a multicenter case-control study that included 105 participants. Clinical and demographic characterists together with hemogram parameters, soluble pro and anti-inflamatory factors, and specific innate and adaptive immune cell populations were compared among patients with current SI/SA (n = 21), a history of lifetime SI/SA (n = 42), and HC (n = 42). ResultsPatients with both current and lifetime SI/SA had a significant increase in the absolute count of monocytes and in the monocyte/lymphocyte ratio (MLR). Additionally, patients with current and lifetime SI/SA showed a significant increase in high-sensitivity C- reactive protein (hs-CRP), and patients with lifetime SI/SA also showed higher levels of Erythrocyte Sedimentation Rate (ESR). The cellular inflammatory status of patients with SI/SA was characterized by altered proportions of monocytes with higher levels of nonclassical and intermediate monocytes. No differences were observed in the number of lymphocytes and the proportion of CD4 and CD8 between patients and HC, but we found differences in markers of exhaustion of CD4 lymphocytes, with increased levels of Programmed cell death protein 1 (PD1) in Current SI/SA and Lymphocyte activation gene 3 (LAG3) in Current SI/SA and Lifetime SI/SA compared to HC. The plasmainflammatory status was marked by higher levels of soluble Triggering receptor expressed on myeloid cells 2 (sTREM2) in patients with lifetime SI/SA compared to HC. Finally, the multinomial analysis indicates that inflammation and depressive symptoms are independently associated with SI/SA. ConclusionThis study highlights the association of immunological alterations with SI/SA. Furthremore, SI/SA is independently influenced by depressive symptoms and inflammation. This may have important therapeutic implications, as in these patients, it may be necessary to treat the inflammatory process beyond treating the depressive symptoms.

A novel TCGA-validated programmed cell-death-related signature of ovarian cancer

BackgroundOvarian cancer (OC) is a gynecological malignancy tumor with high recurrence and mortality rates. Programmed cell death (PCD) is an essential regulator in cancer metabolism, whose functions are still unknown in OC. Therefore, it is vital to determine the prognostic value and therapy response of PCD-related genes in OC.MethodsBy mining The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx) and Genecards databases, we constructed a prognostic PCD-related genes model and performed Kaplan-Meier (K-M) analysis and Receiver Operating Characteristic (ROC) curve for its predictive ability. A nomogram was created via Cox regression. We validated our model in train and test sets. Quantitative real-time PCR (qRT-PCR) was applied to identify the expression of our model genes. Finally, we analyzed functional analysis, immune infiltration, genomic mutation, tumor mutational burden (TMB) and drug sensitivity of patients in low- and high-risk group based on median scores.ResultsA ten-PCD-related gene signature including protein phosphatase 1 regulatory subunit 15 A (PPP1R15A), 8-oxoguanine-DNA glycosylase (OGG1), HECT and RLD domain containing E3 ubiquitin protein ligase family member 1 (HERC1), Caspase-2.(CASP2), Caspase activity and apoptosis inhibitor 1(CAAP1), RB transcriptional corepressor 1(RB1), Z-DNA binding protein 1 (ZBP1), CD3-epsilon (CD3E), Clathrin heavy chain like 1(CLTCL1), and CCAAT/enhancer-binding protein beta (CEBPB) was constructed. Risk score performed well with good area under curve (AUC) (AUC3 − year =0.728, AUC5 − year = 0.730). The nomogram based on risk score has good performance in predicting the prognosis of OC patients (AUC1 − year =0.781, AUC3 − year =0.759, AUC5 − year = 0.670). Kyoto encyclopedia of genes and genomes (KEGG) analysis showed that the erythroblastic leukemia viral oncogene homolog (ERBB) signaling pathway and focal adhesion were enriched in the high-risk group. Meanwhile, patients with high-risk scores had worse OS. In addition, patients with low-risk scores had higher immune-infiltrating cells and enhanced expression of checkpoints, programmed cell death 1 ligand 1 (PD-L1), indoleamine 2,3-dioxygenase 1 (IDO-1) and lymphocyte activation gene-3 (LAG3), and were more sensitive to A.443,654, GDC.0449, paclitaxel, gefitinib and cisplatin. Finally, qRT-PCR confirmed RB1, CAAP1, ZBP1, CEBPB and CLTCL1 over-expressed, while PPP1R15A, OGG1, CASP2, CD3E and HERC1 under-expressed in OC cell lines.ConclusionOur model could precisely predict the prognosis, immune status and drug sensitivity of OC patients.

Immune Regulation Patterns in Response to Environmental Pollutant Chromate Exposure-Related Genetic Damage: A Cross-Sectional Study Applying Machine Learning Methods.

Exposure to hexavalent chromium damages genetic materials like DNA and chromosomes, further elevating cancer risk, yet research rarely focuses on related immunological mechanisms, which play an important role in the occurrence and development of cancer. We investigated the association between blood chromium (Cr) levels and genetic damage biomarkers as well as the immune regulatory mechanism involved, such as costimulatory molecules, in 120 workers exposed to chromates. Higher blood Cr levels were linearly correlated with higher genetic damage, reflected by urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and blood micronucleus frequency (MNF). Exploratory factor analysis revealed that both positive and negative immune regulation patterns were positively associated with blood Cr. Specifically, higher levels of programmed cell death protein 1 (PD-1; mediated proportion: 4.12%), programmed cell death ligand 1 (PD-L1; 5.22%), lymphocyte activation gene 3 (LAG-3; 2.11%), and their constitutive positive immune regulation pattern (5.86%) indirectly positively influenced the relationship between blood Cr and urinary 8-OHdG. NOD-like receptor family pyrin domain containing 3 (NLRP3) positively affected the association between blood Cr levels and inflammatory immunity. This study, using machine learning, investigated immune regulation and its potential role in chromate-induced genetic damage, providing insights into complex relationships and emphasizing the need for further research.

Human umbilical cord mesenchymal stem cell-derived exosomes alleviate the severity of experimental autoimmune encephalomyelitis and enhance lag-3 expression on foxp3 + CD4 + T cells.

Multiple sclerosis (MS) is a complex autoimmune disease that affects the central nervous system, causing inflammation, demyelination, and neurodegeneration. Understanding the dysregulation of Tregs, dynamic cells involved in autoimmunity, is crucial in comprehending diseases like MS. However, the role of lymphocyte-activation gene 3 (Lag-3) in MS remains unclear. In this study, we explore the potential of exosomes derived from human umbilical cord mesenchymal stem cells (hUMSCs-Exs) as an immune modulator in experimental autoimmune encephalomyelitis (EAE), a model for MS. Using flow cytometry, our research findings indicate that groups receiving treatment with hUMSC-Exs revealed a significant increase in Lag-3 expression on Foxp3 + CD4 + T cells. Furthermore, cell proliferation conducted on spleen tissue samples from EAE mice using the CFSE method exposed to hUMSC-Exs yielded relevant results. These results suggest that hUMSCs-Exs could be a promising anti-inflammatory agent to regulate T-cell responses in EAE and other autoimmune diseases. However, further research is necessary to fully understand the underlying mechanisms and Lag-3's precise role in these conditions.