ABSTRACT
One way memory B cells provide protection is by rapidly differentiating into plasma cells. Plasma cells are vital in providing long-term protection against pathogens; however, they can also be detrimental to health in the case of antibody-mediated autoimmunity. Therefore, compounds which modulate the survival of plasma cells have been of interest for therapeutic intervention. Investigation of ex vivo plasma cell survival has previously been limited by the low frequency of plasma cells in the blood. Here we describe a novel ex vivo culture system that only requires 3000-5000 cells per condition. This method permits the assessment of human plasma cell survival derived from blood and can assess the impact of small molecule inhibitors on plasma cell viability.
Subject(s)
Cell Survival , Plasma Cells , Humans , Plasma Cells/immunology , Plasma Cells/cytology , Plasma Cells/drug effects , Cell Survival/drug effects , Cell Culture Techniques/methods , Cells, Cultured , Flow Cytometry/methodsABSTRACT
BACKGROUND: Ascorbic acid can regulate the function of the immune system. This study aimed to investigate the underlying mechanisms of ascorbic acid in plasma cell differentiation and rheumatoid arthritis (RA). METHODS: Mice were intraperitoneally injected with either ascorbic acid or an equivalent volume of phosphate-buffered saline (PBS). To elucidate the effects of ascorbic acid on arthritis, we utilized a collagen induced arthritis mouse model (CIA). To investigate the effects of ascorbic acid on antibody response, mice were immunized with (4-Hydroxy-3-nitrophenylacetyl)-Ficoll (NP-Ficoll) or (4-hydroxy-3-nitrophenyl) acetyl-keyhole limpet hemocyanin (NP-KLH) to elicit a T-cell independent (TI) or T-cell dependent (TD) antibody response. To clarify the ability of ascorbic acid on plasma cell production, we tracked the B cell differentiation fate on the NP-specific B1-8hi BCR transgenic background. RESULTS: Ascorbic acid-injected mice demonstrated significantly delayed disease incidence and decreased disease severity compared to PBS-injected mice. Ascorbic acid can reduce the titers of autoantibodies in both arthritis and lupus mice models. Ascorbic acid can significantly reduce the number of plasma cells and the production of antigen-specific antibodies in TI and TD antibody response. In addition, ascorbic acid can disrupt the antibody affinity maturation. Through B1-8hi adoptive transfer experiments, it has been demonstrated that ascorbic acid restrains B cell differentiation into plasma cells in a cell-intrinsic manner. After in-depth exploration, we found that ascorbic acid can block the cell cycle of B cells and promote cell apoptosis. Mechanistically, ascorbic acid inhibited the production of autoreactive plasma cells by inhibiting the Stat3 signaling pathway. CONCLUSION: Our study demonstrates that ascorbic acid has the ability to suppress the generation of autoreactive plasma cells, diminish the production of autoantibodies, and consequently delay the onset of rheumatoid arthritis.
Subject(s)
Arthritis, Rheumatoid , Ascorbic Acid , Autoantibodies , Animals , Autoantibodies/immunology , Autoantibodies/blood , Ascorbic Acid/pharmacology , Ascorbic Acid/therapeutic use , Arthritis, Rheumatoid/immunology , Arthritis, Rheumatoid/drug therapy , Arthritis, Rheumatoid/pathology , Mice , Arthritis, Experimental/immunology , Arthritis, Experimental/drug therapy , Cell Differentiation/drug effects , Plasma Cells/immunology , Plasma Cells/drug effectsABSTRACT
Multiple myeloma (MM) is an incurable plasma cell malignancy that exploits transcriptional networks driven by IRF4. We employ a multi-omics approach to discover IRF4 vulnerabilities, integrating functional genomics screening, spatial proteomics, and global chromatin mapping. ARID1A, a member of the SWI/SNF chromatin remodeling complex, is required for IRF4 expression and functionally associates with IRF4 protein on chromatin. Deleting Arid1a in activated murine B cells disrupts IRF4-dependent transcriptional networks and blocks plasma cell differentiation. Targeting SWI/SNF activity leads to rapid loss of IRF4-target gene expression and quenches global amplification of oncogenic gene expression by MYC, resulting in profound toxicity to MM cells. Notably, MM patients with aggressive disease bear the signature of SWI/SNF activity, and SMARCA2/4 inhibitors remain effective in immunomodulatory drug (IMiD)-resistant MM cells. Moreover, combinations of SWI/SNF and MEK inhibitors demonstrate synergistic toxicity to MM cells, providing a promising strategy for relapsed/refractory disease.
Subject(s)
DNA-Binding Proteins , Interferon Regulatory Factors , Multiple Myeloma , Plasma Cells , Transcription Factors , Multiple Myeloma/drug therapy , Multiple Myeloma/pathology , Multiple Myeloma/genetics , Multiple Myeloma/metabolism , Interferon Regulatory Factors/metabolism , Interferon Regulatory Factors/genetics , Animals , Transcription Factors/metabolism , Transcription Factors/genetics , Humans , Mice , DNA-Binding Proteins/metabolism , DNA-Binding Proteins/genetics , Plasma Cells/drug effects , Plasma Cells/metabolism , Plasma Cells/pathology , Gene Expression Regulation, Neoplastic/drug effects , Cell Line, Tumor , Cell Differentiation/drug effectsABSTRACT
BACKGROUND AND OBJECTIVES: Interleukin-6 receptor antibodies (IL-6R Abs), including satralizumab, are increasingly used to prevent relapse for neuromyelitis optica spectrum disorder (NMOSD). However, the detailed mechanism of action of this treatment on the lymphocyte phenotype remains unclear. This study focused on B cells in patients with NMOSD, hypothesizing that IL-6R Ab enables B cells to acquire regulatory functions by producing the anti-inflammatory cytokine IL-10. METHODS: Peripheral blood mononuclear cells were stimulated in vitro to induce the expansion of B-cell subsets, double-negative B cells (DNs; CD19+ IgD-, CD27-) and plasmablasts (PBs; CD19+, CD27hi, CD38hi). Whole B cells, DNs, or PBs were isolated after culture with IL-6R Ab, and IL-10 expression was quantified using quantitative PCR and a cytometric bead array. RNA sequencing was performed to identify the marker of regulatory PBs induced by IL-6R Ab. RESULTS: DNs and PBs were observed to expand in patients with NMSOD during the acute attacks. In the in vitro model, IL-6R Ab increased IL-10 expression in B cells. Notably, IL-10 expression increased in PBs but not in DNs. Using RNA sequencing, CD200 was identified as a marker of regulatory PBs among the differentially expressed upregulated genes. CD200+ PBs produced more IL-10 than CD200- PBs. Furthermore, patients with NMOSD who received satralizumab had a higher proportion of CD200+ PBs than patients during the acute attacks. DISCUSSION: Treatment with IL-6 signaling blockade elicited a regulatory phenotype in B cells and PBs. CD200+ PBs may be a marker of treatment responsiveness in the context of NMOSD pathophysiology.
Subject(s)
Interleukin-6 , Neuromyelitis Optica , Receptors, Interleukin-6 , Humans , Neuromyelitis Optica/drug therapy , Neuromyelitis Optica/immunology , Female , Adult , Male , Middle Aged , Interleukin-6/metabolism , Receptors, Interleukin-6/antagonists & inhibitors , Plasma Cells/drug effects , Plasma Cells/immunology , Interleukin-10/metabolism , Signal Transduction/drug effectsABSTRACT
Systemic lupus erythematosus (SLE) is a multifaceted autoimmune disorder characterized by diverse clinical manifestations and organ damage. Despite its elusive etiology, dysregulated subsets and functions of B cells are pivotal in SLE pathogenesis. Peoniflorin-6'-O-benzene sulfonate (CP-25), an esterification modification of Paeoniflorin, exhibits potent anti-inflammatory and immunomodulatory properties in autoimmune diseases (AID). However, the involvement of CP-25 and its target, GRK2, in SLE development has not been explored. In this study, we demonstrate that both genetic deficiency and pharmacological inhibition of GRK2 attenuate autoantibodies production, reduce systemic inflammation, and mitigate histopathological alterations in the spleen and kidney in the pristane-induced mouse SLE model. Importantly, our findings highlight that both genetic deficiency and pharmacological inhibition of GRK2 suppress plasma cells generation and restore dysregulated B-cell subsets by modulating two crucial transcription factors, Blimp1 and IRF4. Collectively, targeting GRK2 with CP-25 emerges as a promising therapeutic approach for SLE.
Subject(s)
Disease Models, Animal , G-Protein-Coupled Receptor Kinase 2 , Lupus Erythematosus, Systemic , Plasma Cells , Animals , Female , Mice , Anti-Inflammatory Agents/pharmacology , Autoantibodies/blood , Cell Differentiation/drug effects , G-Protein-Coupled Receptor Kinase 2/antagonists & inhibitors , G-Protein-Coupled Receptor Kinase 2/metabolism , Glucosides/pharmacology , Kidney/pathology , Kidney/drug effects , Lupus Erythematosus, Systemic/chemically induced , Lupus Erythematosus, Systemic/drug therapy , Lupus Erythematosus, Systemic/pathology , Mice, Inbred C57BL , Mice, Knockout , Monoterpenes/pharmacology , Plasma Cells/drug effects , Positive Regulatory Domain I-Binding Factor 1/metabolism , Positive Regulatory Domain I-Binding Factor 1/genetics , Spleen/drug effects , Spleen/pathology , Spleen/immunology , TerpenesABSTRACT
INTRODUCTION: Severe Graves' disease is a life-changing condition with poor outcomes from currently available treatments. It is caused by directly pathogenic thyroid-stimulating hormone receptor-stimulating antibodies (TRAb), which are secreted from plasma cells. The human anti-CD38 monoclonal antibody daratumumab was developed to target plasma cells which express high levels of CD38, and is currently licensed for treatment of the plasma cell malignancy, myeloma. However, it can also deplete benign plasma cells with the potential to reduce TRAb and alter the natural history of severe Graves' disease. This study aims to establish proof of concept that daratumumab has efficacy in patients with severe Graves' disease and will provide important data to inform a choice of dosing regimen for subsequent trials. METHODS AND ANALYSIS: The Graves-PCD trial aims to determine if daratumumab modulates the humoral immune response in patients with severe Graves' disease, and if so, over what time period, and to find an optimal dose. It is a single-blinded, randomised, dose-finding, adaptive trial using four different doses of daratumumab or placebo in 30 adult patients. Part 1 of the trial is dose-finding and, following an interim analysis, in part 2, the remaining patients will be randomised between the chosen dose(s) from the interim analysis or placebo. The primary outcome is the percentage change in serum TRAb from baseline to 12 weeks. ETHICS AND DISSEMINATION: The trial received a favourable ethical opinion from London-Hampstead Research Ethics Committee (reference 21/LO/0449). The results of this trial will be disseminated at international meetings, in the peer-reviewed literature and through partner patient group newsletters and presentations at patient education events. TRIAL REGISTRATION NUMBER: ISRCTN81162400.
Subject(s)
Antibodies, Monoclonal , Graves Disease , Humans , Graves Disease/drug therapy , Antibodies, Monoclonal/therapeutic use , Antibodies, Monoclonal/administration & dosage , Randomized Controlled Trials as Topic , Plasma Cells/drug effects , Single-Blind Method , Adult , Male , Female , Dose-Response Relationship, DrugABSTRACT
Primary Sjögren's syndrome (pSS) is a chronic inflammatory autoimmune disease with an unclear pathogenesis, and there is currently no approved drug for the treatment of this disease. Iguratimod, as a novel clinical anti-rheumatic drug in China and Japan, has shown remarkable efficacy in improving the symptoms of patients with pSS in clinical studies. In this study we investigated the mechanisms underlying the therapeutic effect of iguratimod in the treatment of pSS. Experimental Sjögren's syndrome (ESS) model was established in female mice by immunizing with salivary gland protein. After immunization, ESS mice were orally treated with iguratimod (10, 30, 100 mg·kg-1·d-1) or hydroxychloroquine (50 mg·kg-1·d-1) for 70 days. We showed that iguratimod administration dose-dependently increased saliva secretion, and ameliorated ESS development by predominantly inhibiting B cells activation and plasma cell differentiation. Iguratimod (30 and 100 mg·kg-1·d-1) was more effective than hydroxychloroquine (50 mg·kg-1·d-1). When the potential target of iguratimod was searched, we found that iguratimod bound to TEC kinase and promoted its degradation through the autophagy-lysosome pathway in BAFF-activated B cells, thereby directly inhibiting TEC-regulated B cells function, suggesting that the action mode of iguratimod on TEC was different from that of conventional kinase inhibitors. In addition, we found a crucial role of TEC overexpression in plasma cells of patients with pSS. Together, we demonstrate that iguratimod effectively ameliorates ESS via its unique suppression of TEC function, which will be helpful for its clinical application. Targeting TEC kinase, a new regulatory factor for B cells, may be a promising therapeutic option.
Subject(s)
Cell Differentiation , Chromones , Plasma Cells , Protein-Tyrosine Kinases , Sjogren's Syndrome , Sulfonamides , Animals , Sjogren's Syndrome/drug therapy , Female , Cell Differentiation/drug effects , Mice , Protein-Tyrosine Kinases/antagonists & inhibitors , Protein-Tyrosine Kinases/metabolism , Plasma Cells/drug effects , Chromones/pharmacology , Chromones/therapeutic use , Sulfonamides/pharmacology , Sulfonamides/therapeutic use , Benzofurans/pharmacology , Benzofurans/therapeutic use , Hydroxychloroquine/pharmacology , Hydroxychloroquine/therapeutic use , Disease Models, Animal , Humans , B-Lymphocytes/drug effects , B-Lymphocytes/metabolism , Antirheumatic Agents/pharmacology , Antirheumatic Agents/therapeutic useABSTRACT
The infection of coronavirus disease (COVID-19) seriously threatens human life. It is urgent to generate effective and safe specific antibodies (Abs) against the pathogenic elements of COVID-19. Mice were immunized with SARS-CoV-2 spike protein antigens: S ectodomain-1 (CoV, in short) mixed in Alum adjuvant for 2 times and boosted with CoV weekly for 6 times. A portion of mice were treated with Maotai liquor (MTL, in short) or/and heat stress (HS) together with CoV boosting. We observed that the anti-CoV Ab was successfully induced in mice that received the CoV/Alum immunization for 2 times. However, upon boosting with CoV, the CoV Ab production diminished progressively; spleen CoV Ab-producing plasma cell counts reduced, in which substantial CoV-specific Ab-producing plasma cells (sPC) were apoptotic. Apparent oxidative stress signs were observed in sPCs; the results were reproduced by exposing sPCs to CoV in the culture. The presence of MTL or/and HS prevented the CoV-induced oxidative stress in sPCs and promoted and stabilized the CoV Ab production in mice in re-exposure to CoV. In summary, CoV/Alum immunization can successfully induce CoV Ab production in mice that declines upon reexposure to CoV. Concurrent administration of MTL/HS stabilizes and promotes the CoV Ab production in mice.
Subject(s)
Antibodies, Neutralizing/biosynthesis , Antibodies, Viral/biosynthesis , Apoptosis , COVID-19/immunology , Plasma Cells/immunology , SARS-CoV-2/physiology , Superoxide Dismutase-1/physiology , Adjuvants, Immunologic , Alcoholic Beverages , Alum Compounds , Angiotensin-Converting Enzyme 2/physiology , Animals , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19/enzymology , COVID-19 Vaccines/immunology , Heat-Shock Response , Immunization, Secondary , Immunogenicity, Vaccine , Janus Kinase 2/physiology , Male , Mice , Mice, Inbred C57BL , Oxidative Stress , Plasma Cells/drug effects , Plasma Cells/pathology , Reactive Oxygen Species/metabolism , STAT1 Transcription Factor/physiology , Signal Transduction , Specific Pathogen-Free Organisms , Spike Glycoprotein, Coronavirus/immunology , VaccinationABSTRACT
Pyruvate dehydrogenase kinase 1 (PDK1) is a Ser/Thr kinase that inactivates mitochondrial pyruvate dehydrogenase (PDH), leading to switch of glucose metabolism from mitochondrial oxidation to aerobic glycolysis. We previously reported that PDK1 inhibition is a potent therapeutic strategy in multiple myeloma (MM). However, availability of PDK1 inhibitors, which are effective at low concentrations, are limited at present, making PDK1 inhibition difficult to apply in the clinic. In the present study, we examined the efficacy and mechanism of action of JX06, a novel PDK1 inhibitor, against MM cells. We confirmed that PDK1 is highly expressed in normal plasma cells and MM cells using publicly available gene expression datasets. JX06 suppressed cell growth and induced apoptosis against MM cells from approximately 0.5 µM JX06 treatment reduced PDH phosphorylation, suggesting that JX06 is indeed inhibiting PDK1. Intracellular metabolite analysis revealed that JX06 treatment reduced metabolites associated with glucose metabolism of MM cells. Additionally, JX06 in combination with a well-known proteasome inhibitor, bortezomib, significantly increased MM cell death, which raises the possibility of combination use of JX06 with proteasome inhibitors in the clinic. These findings demonstrate that PDK1 can be potentially targeted by JX06 in MM through glycolysis inhibition, leading to a novel therapeutic strategy in MM.
Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Disulfiram/analogs & derivatives , Enzyme Inhibitors/pharmacology , Glycolysis/drug effects , Morpholines/pharmacology , Antineoplastic Combined Chemotherapy Protocols , Apoptosis/genetics , Bortezomib/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Datasets as Topic , Disulfiram/pharmacology , Drug Synergism , Gene Expression Regulation, Neoplastic , Glycolysis/genetics , Humans , Ketone Oxidoreductases/genetics , Ketone Oxidoreductases/metabolism , Mitochondria/drug effects , Mitochondria/enzymology , Mitochondria/pathology , Molecular Targeted Therapy , Multiple Myeloma/drug therapy , Multiple Myeloma/enzymology , Multiple Myeloma/genetics , Multiple Myeloma/pathology , Phosphorylation/drug effects , Plasma Cells/drug effects , Plasma Cells/enzymology , Plasma Cells/pathology , Pyruvate Dehydrogenase Acetyl-Transferring Kinase/antagonists & inhibitors , Pyruvate Dehydrogenase Acetyl-Transferring Kinase/metabolismSubject(s)
Antibodies, Monoclonal/therapeutic use , Antineoplastic Agents/therapeutic use , Clone Cells/drug effects , Multiple Myeloma/drug therapy , Plasma Cells/drug effects , Clone Cells/pathology , Follow-Up Studies , Humans , Multiple Myeloma/pathology , Plasma Cells/pathology , Prognosis , Retrospective Studies , Survival RateABSTRACT
B cell differentiation into Ab-secreting plasma cells requires transcriptional, metabolic, and epigenetic remodeling. Histone H3 lysine 27 trimethylation (H3K27me3), a histone modification associated with gene silencing, is dynamically regulated during B cell differentiation. Although several studies have focused on mechanisms involving the gain of this modification in plasmablasts (PB), the role of active demethylation of H3K27me3 by ubiquitously transcribed tetratricopeptide repeat, X chromosome (UTX) and Jumonji domain-containing protein 3 (JMDJ3) during B cell differentiation has not been examined. In this study, this process was assessed using a pharmacological inhibitor of UTX and JMJD3, GSK-J4. Treatment of ex vivo stimulated mouse B cells with GSK-J4 led to an increase in PB frequency without affecting the ability of the newly formed PB to secrete Abs. Consistent with the role of UTX and JMJD3 in promoting gene expression, the majority of differentially expressed were downregulated upon GSK-J4 treatment. GSK-J4-treated cells downregulated genes associated with signaling and P53 pathways. Inhibitor treated cells upregulated genes associated with cell cycle and proliferation, which correlated with an increase in actively proliferating cells. Unexpectedly, a majority of the downregulated transcripts corresponded to genes that in the wild-type setting were genes that gain H3K27me3 and downregulated in PB. Together, our results show that UTX and JMDJ3 are required to restrain B cell differentiation and suggest that they function as a rheostat for H3K27me3 to control this process.
Subject(s)
Cell Differentiation/drug effects , Histone Demethylases/metabolism , Jumonji Domain-Containing Histone Demethylases/metabolism , Plasma Cells/metabolism , Animals , Benzazepines/pharmacology , Mice , Mice, Inbred C57BL , Plasma Cells/drug effects , Pyrimidines/pharmacology , Signal Transduction/drug effectsABSTRACT
Polyphenols from olive oil are endowed with several biological activities. Chemical modifications have been recently applied to these compounds to improve their therapeutic activity in different pathological settings, including cancer. Herein, we describe the in vitro effects on multiple myeloma (MM) cells of oleil hydroxytyrosol (HTOL), a synthetic fatty ester of natural hydroxytyrosol with oleic acid. HTOL reduced the viability of various human MM cell lines (HMCLs), even when co-cultured with bone marrow stromal cells, triggering ER stress, UPR and apoptosis, while it was not cytotoxic against healthy peripheral blood mononuclear cells or B lymphocytes. Whole-transcriptome profiling of HTOL-treated MM cells, coupled with protein expression analyses, indicate that HTOL antagonizes key survival pathways for malignant plasma cells, including the undruggable IRF4-c-MYC oncogenic axis. Accordingly, c-MYC gain- and loss-of-function strategies demonstrate that HTOL anti-tumor activity was, at least in part, due to c-MYC targeting. Taken together, these findings underscore the anti-MM potential of HTOL, providing the molecular framework for further investigation of HTOL-based treatments as novel anti-cancer agents.
Subject(s)
Antineoplastic Agents/pharmacology , Multiple Myeloma/drug therapy , Phenylethyl Alcohol/analogs & derivatives , Plasma Cells/drug effects , Antineoplastic Agents/chemistry , Cell Line, Tumor , Humans , Multiple Myeloma/metabolism , Multiple Myeloma/pathology , Phenylethyl Alcohol/chemistry , Phenylethyl Alcohol/pharmacology , Plasma Cells/metabolism , Plasma Cells/pathology , Signal Transduction/drug effectsABSTRACT
Multiple Myeloma (MM) is an incurable hematologic malignancy of terminally differentiated plasma cells (PCs), where immune interactions play a key role in the control of cancer cell growth and survival. In particular, MM is characterized by a highly immunosuppressive bone marrow microenvironment where the anticancer/cytotoxic activity of Natural Killer (NK) cells is impaired. This study is focused on understanding whether modulation of neddylation can regulate NK cell-activating ligands expression and sensitize MM to NK cell killing. Neddylation is a post-translational modification that adds a ubiquitin-like protein, NEDD8, to selected substrate proteins, affecting their stability, conformation, subcellular localization, and function. We found that pharmacologic inhibition of neddylation using a small-molecule inhibitor, MLN4924/Pevonedistat, increases the expression of the NK cell-activating receptor NKG2D ligands MICA and MICB on the plasma membrane of different MM cell lines and patient-derived PCs, leading to enhanced NK cell degranulation. Mechanistically, MICA expression is upregulated at mRNA level, and this is the result of an increased promoter activity after the inhibition of IRF4 and IKZF3, two transcriptional repressors of this gene. Differently, MLN4924/Pevonedistat induced accumulation of MICB on the plasma membrane with no change of its mRNA levels, indicating a post-translational regulatory mechanism. Moreover, inhibition of neddylation can cooperate with immunomodulatory drugs (IMiDs) in upregulating MICA surface levels in MM cells due to increased expression of CRBN, the cellular target of these drugs. In summary, MLN4924/Pevonedistat sensitizes MM to NK cell recognition, adding novel information on the anticancer activity of neddylation inhibition.
Subject(s)
Histocompatibility Antigens Class I/metabolism , Immunomodulation , Killer Cells, Natural/immunology , Multiple Myeloma/immunology , NEDD8 Protein/antagonists & inhibitors , NK Cell Lectin-Like Receptor Subfamily K/metabolism , Up-Regulation , Aged , Aged, 80 and over , Cell Degranulation/drug effects , Cell Line, Tumor , Cyclopentanes/pharmacology , Female , Gene Expression Regulation, Neoplastic/drug effects , Histocompatibility Antigens Class I/genetics , Humans , Immunologic Factors/pharmacology , Immunomodulation/drug effects , Intracellular Signaling Peptides and Proteins/metabolism , Killer Cells, Natural/drug effects , Killer Cells, Natural/physiology , Ligands , Male , Middle Aged , Multiple Myeloma/genetics , Multiple Myeloma/pathology , NEDD8 Protein/metabolism , Plasma Cells/drug effects , Plasma Cells/metabolism , Promoter Regions, Genetic/genetics , Pyrimidines/pharmacologyABSTRACT
Kawasaki disease (KD) is the most common cause of acquired heart disease in children in developed countries. Although functional and phenotypic changes of immune cells have been reported, a global understanding of immune responses underlying acute KD is unclear. Here, using single-cell RNA sequencing, we profile peripheral blood mononuclear cells from seven patients with acute KD before and after intravenous immunoglobulin therapy and from three age-matched healthy controls. The most differentially expressed genes are identified in monocytes, with high expression of pro-inflammatory mediators, immunoglobulin receptors and low expression of MHC class II genes in acute KD. Single-cell RNA sequencing and flow cytometry analyses, of cells from an additional 16 KD patients, show that although the percentage of total B cells is substantially decreased after therapy, the percentage of plasma cells among the B cells is significantly increased. The percentage of CD8+ T cells is decreased in acute KD, notably effector memory CD8+ T cells compared with healthy controls. Oligoclonal expansions of both B cell receptors and T cell receptors are observed after therapy. We identify biological processes potentially underlying the changes of each cell type. The single-cell landscape of both innate and adaptive immune responses provides insights into pathogenesis and therapy of KD.
Subject(s)
B-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Monocytes/immunology , Mucocutaneous Lymph Node Syndrome/genetics , Plasma Cells/immunology , Acute Disease , Adaptive Immunity/drug effects , B-Lymphocytes/drug effects , B-Lymphocytes/pathology , CD8-Positive T-Lymphocytes/drug effects , CD8-Positive T-Lymphocytes/pathology , Case-Control Studies , Cell Proliferation , Child , Child, Preschool , Clone Cells , Female , Gene Expression , Humans , Immunity, Innate/drug effects , Immunoglobulins, Intravenous/therapeutic use , Immunophenotyping , Male , Monocytes/drug effects , Monocytes/pathology , Mucocutaneous Lymph Node Syndrome/drug therapy , Mucocutaneous Lymph Node Syndrome/immunology , Mucocutaneous Lymph Node Syndrome/pathology , Plasma Cells/drug effects , Plasma Cells/pathology , Receptors, Antigen, B-Cell/genetics , Receptors, Antigen, B-Cell/immunology , Receptors, Antigen, T-Cell/genetics , Receptors, Antigen, T-Cell/immunology , Sequence Analysis, RNA , Single-Cell AnalysisABSTRACT
Multiple myeloma (MM) is an incurable disease characterized by malignant plasma cell clonal expansion in the bone marrow; therefore, inhibiting the proliferation of plasma cells is an important approach to overcome the progression of MM. Quercetin (Que) is a promising flavonoid with broad-spectrum anti-tumor activity against various cancers, including MM; however, the underlying mechanism is not yet understood. The present study aimed to reveal the gene expression profile of Que-treated MM cells and clarify its potential mechanism. The 30% inhibitory concentration (IC30) of Que against MM cells was calculated, and the proliferation rate was significantly reduced after Que treatment. Next, 495 dysregulated genes were identified via RNA sequencing in Que-treated MM cells. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes analyses indicated that the dysregulated genes were enriched in various apoptosis-related GO terms and amino acid metabolism-related pathways. qPCR validation showed that protein tyrosine phosphatase receptor-type R (PTPRR) had the highest verified log2 FC (abs) among the top 15 dysregulated genes. Overexpression of PTPRR increased the sensitivity of MM cells against Que, significantly inhibiting their proliferation and colony formation ability; silencing of PTPRR showed the opposite results. Furthermore, bioinformatics analyses and PPI network construction of PTPRR indicated that dephosphorylation of ERK might be the potential pathway for the PTPRR-induced inhibition of MM cell proliferation. In summary, our study identified the gene expression profile in Que-treated MM cells and demonstrated that the upregulation of PTPRR was one of the important mechanisms for the Que-induced inhibition of MM cell proliferation.
Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Cell Proliferation/drug effects , Extracellular Signal-Regulated MAP Kinases/genetics , Plasma Cells/drug effects , Quercetin/pharmacology , Receptor-Like Protein Tyrosine Phosphatases, Class 7/genetics , Cell Line, Tumor , Extracellular Signal-Regulated MAP Kinases/metabolism , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Gene Ontology , Humans , Metabolic Networks and Pathways/drug effects , Metabolic Networks and Pathways/genetics , Molecular Sequence Annotation , Plasma Cells/metabolism , Plasma Cells/pathology , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Receptor-Like Protein Tyrosine Phosphatases, Class 7/antagonists & inhibitors , Receptor-Like Protein Tyrosine Phosphatases, Class 7/metabolism , Signal TransductionABSTRACT
Antibody-mediated autoimmune-like hepatitis is a rare and challenging occurrence after hematopoietic cell transplant (HCT). We present the case of a 16-year-old male patient with Ph+ ALL who underwent matched sibling donor HCT and developed autoimmune-like hepatitis after receiving ponatinib for post-HCT maintenance, evidenced by marked plasma cell infiltrate on liver biopsy. He was successfully treated with steroids and daratumumab, an anti-CD38-monoclonal antibody. The dramatic response in this patient warrants expanded investigation of daratumumab for plasma cell-mediated disorders post-HCT. It further highlights that identifying mechanisms of immune-mediated injury can allow for directed therapy and limit exposure to broad immune suppression.
Subject(s)
Antibodies, Monoclonal/therapeutic use , Hematopoietic Stem Cell Transplantation , Hepatitis, Autoimmune , Plasma Cells/drug effects , Adolescent , Hematopoietic Stem Cell Transplantation/adverse effects , Hepatitis, Autoimmune/drug therapy , Hepatitis, Autoimmune/etiology , Humans , MaleABSTRACT
Telitacicept (Tai'ai®) is fusion protein comprising a recombinant transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI) receptor fused to the fragment crystallizable (Fc) domain of human immunoglobulin G (IgG). Telitacicept is being developed by Yantai Rongchang Pharmaceutical through its subsidiary RemeGen for the treatment of B cell-mediated autoimmune diseases, such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA) and multiple sclerosis (MS). Telitacicept binds to and neutralizes the activity of two cell-signalling molecules, B-lymphocyte stimulator (BLyS) and a proliferation-inducing ligand (APRIL), thereby suppressing the development and survival of plasma cells and mature B cells. In March 2021, telitacicept received its first approval in China for the treatment of patients with active SLE. Clinical studies of telitacicept in several other indications, including IgA nephropathy, MS, myasthenia gravis, neuromyelitis optica spectrum disorders, RA and Sjögren's syndrome are underway in China. This article summarizes the milestones in the development of telitacicept leading to this first approval for SLE.
Subject(s)
Immunosuppressive Agents/therapeutic use , Lupus Erythematosus, Systemic/drug therapy , Recombinant Fusion Proteins/therapeutic use , Arthritis, Rheumatoid/drug therapy , B-Cell Activating Factor/drug effects , China , Drug Approval , Humans , Immunoglobulin G , Multiple Sclerosis/drug therapy , Plasma Cells/drug effects , Tumor Necrosis Factor Ligand Superfamily Member 13/drug effectsABSTRACT
Both acute and chronic antibody-mediated allograft rejection (AMR), which are directly mediated by B cells, remain difficult to treat. Long-lived plasma cells (LLPCs) in bone marrow (BM) play a crucial role in the production of the antibodies that induce AMR. However, LLPCs survive through a T cell-independent mechanism and resist conventional immunosuppressive therapy. Desensitization therapy is therefore performed, although it is accompanied by severe side effects and the pathological condition may be at an irreversible stage when these antibodies, which induce AMR development, are detected in the serum. In other words, AMR control requires the development of a diagnostic method that predicts its onset before LLPC differentiation and enables therapeutic intervention and the establishment of humoral immune monitoring methods providing more detailed information, including individual differences in the susceptibility to immunosuppressive agents and the pathological conditions. In this study, we reviewed recent studies related to the direct or indirect involvement of immunocompetent cells in the differentiation of naïve-B cells into LLPCs, the limitations of conventional methods, and the possible development of novel control methods in the context of AMR. This information will significantly contribute to the development of clinical applications for AMR and improve the prognosis of patients who undergo organ transplantation.
Subject(s)
Antibody-Dependent Cell Cytotoxicity/immunology , B-Lymphocytes/drug effects , B-Lymphocytes/immunology , Graft Rejection/drug therapy , Graft Rejection/etiology , Immunosuppressive Agents/therapeutic use , Allografts/immunology , Animals , B-Lymphocytes/metabolism , Biomarkers , Complement Activation/drug effects , Complement Activation/immunology , Complement System Proteins/immunology , Cytokines/genetics , Cytokines/metabolism , Gene Expression Regulation , Germinal Center/immunology , Germinal Center/metabolism , Graft Rejection/diagnosis , Graft Rejection/metabolism , Humans , Immunologic Memory/drug effects , Immunosuppressive Agents/pharmacology , Immunotherapy , Molecular Diagnostic Techniques/methods , Molecular Targeted Therapy/methods , Plasma Cells/drug effects , Plasma Cells/immunology , Plasma Cells/metabolism , Signal TransductionABSTRACT
Accumulating evidence suggests that cholesterol accumulation in leukocytes is causally associated with the development of autoimmune diseases. However, the mechanism by which fatty acid composition influences autoimmune responses remains unclear. To determine whether the fatty acid composition of diet modulates leukocyte function and the development of systemic lupus erythematosus, we examined the effect of eicosapentaenoic acid (EPA) on the pathology of lupus in drug-induced and spontaneous mouse models. We found that dietary EPA supplementation ameliorated representative lupus manifestations, including autoantibody production and immunocomplex deposition in the kidneys. A combination of lipidomic and membrane dynamics analyses revealed that EPA remodels the lipid composition and fluidity of B cell membranes, thereby preventing B cell differentiation into autoantibody-producing plasma cells. These results highlight a previously unrecognized mechanism by which fatty acid composition affects B cell differentiation into autoantibody-producing plasma cells during autoimmunity, and imply that EPA supplementation may be beneficial for therapy of lupus.
Subject(s)
Autoimmunity/drug effects , Cell Differentiation/drug effects , Dietary Supplements , Eicosapentaenoic Acid/pharmacology , Lupus Erythematosus, Systemic/prevention & control , Plasma Cells/drug effects , Animals , Autoantibodies/immunology , Autoantibodies/metabolism , Autoimmunity/immunology , B-Lymphocytes/drug effects , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Cell Differentiation/immunology , Cells, Cultured , Disease Models, Animal , Eicosapentaenoic Acid/administration & dosage , Female , Kidney/drug effects , Kidney/immunology , Kidney/pathology , Lupus Erythematosus, Systemic/immunology , Mice, Inbred C57BL , Mice, Knockout , Plasma Cells/immunology , Plasma Cells/metabolismABSTRACT
The presence of anti-human leucocyte antigen (HLA) antibodies in the potential solid organ transplant recipient's blood is one of the main barriers to access to a transplantation. The HLA sensitization is associated with longer waitlist time, antibody mediated rejection and transplant lost leading to increased recipient's morbidity and mortality. However, solid organ transplantation across the HLA immunological barriers have been reported in recipients who were highly sensitized to HLA using desensitization protocols. These desensitization regimens are focused on the reduction of circulating HLA antibodies. Despite those strategies improve rates of transplantation, it remains several limitations including persistent high rejection rate and worse long-term outcomes when compare with non-sensitized recipient population. Currently, interest is growing in the development of new desensitization approaches which, beyond targeting antibodies, would be based on the modulation of alloimmune pathways. Plasma cells appears as an interesting target given their critical role in antibody production. In the last decade, CD38-targeting immunotherapies, such as daratumumab, have been recognized as a key component in the treatment of myeloma by inducing an important plasma cell depletion. This review focuses on an emerging concept based on targeting CD38 to desensitize in the field of transplantation.