RESUMEN
Characterizing the compositional and phenotypic characteristics of tumor-infiltrating B cells (TIBs) is important for advancing our understanding of their role in cancer development. Here, we establish a comprehensive resource of human B cells by integrating single-cell RNA sequencing data of B cells from 649 patients across 19 major cancer types. We demonstrate substantial heterogeneity in their total abundance and subtype composition and observe immunoglobulin G (IgG)-skewness of antibody-secreting cell isotypes. Moreover, we identify stress-response memory B cells and tumor-associated atypical B cells (TAABs), two tumor-enriched subpopulations with prognostic potential, shared in a pan-cancer manner. In particular, TAABs, characterized by a high clonal expansion level and proliferative capacity as well as by close interactions with activated CD4 T cells in tumors, are predictive of immunotherapy response. Our integrative resource depicts distinct clinically relevant TIB subsets, laying a foundation for further exploration of functional commonality and diversity of B cells in cancer.
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Neoplasias , Análisis de la Célula Individual , Humanos , Neoplasias/inmunología , Neoplasias/patología , Linfocitos B/inmunología , Linfocitos B/metabolismo , Fenotipo , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Inmunoglobulina G/inmunología , Inmunoglobulina G/metabolismo , Inmunoterapia , PronósticoRESUMEN
Immunofluorescence microscopy is a powerful technique using fluorescently labelled antibodies which can be used to visualize proteins in the nucleus. A key advantage of this method is that it can provide insight into the spatial organization and the localization of nuclear proteins, which can provide elucidation of their function. Here, we provide a protocol for immunofluorescence staining in the nucleus, which has successfully been used to visualize histone modifications and nuclear bodies in human and mouse B lymphocytes, using as few as 1 × 104-5 × 104 cells.
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Epigénesis Genética , Técnica del Anticuerpo Fluorescente , Animales , Ratones , Técnica del Anticuerpo Fluorescente/métodos , Humanos , Núcleo Celular/metabolismo , Subgrupos de Linfocitos B/metabolismo , Subgrupos de Linfocitos B/inmunología , Memoria Inmunológica , Microscopía Fluorescente/métodos , Histonas/metabolismo , Activación de Linfocitos , Coloración y Etiquetado/métodosRESUMEN
Epigenetic programs play a key role in regulating the development and function of immune cells. However, conventional methods for profiling epigenetic mechanisms, such as the post-translational modifications to histones, present several technical challenges that prevent a complete understanding of gene regulation. Here, we provide a detailed protocol of the Cleavage Under Targets and Tagmentation (CUT&Tag) chromatin profiling technique for identifying histone modifications in human and mouse lymphocytes.
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Subgrupos de Linfocitos B , Epigénesis Genética , Epigenómica , Histonas , Humanos , Animales , Ratones , Epigenómica/métodos , Histonas/metabolismo , Subgrupos de Linfocitos B/metabolismo , Subgrupos de Linfocitos B/inmunología , Cromatina/metabolismo , Cromatina/genética , Procesamiento Proteico-Postraduccional , Código de HistonasRESUMEN
The use of flow cytometry for immunophenotyping is contingent on the ability to accurately assign biological relevance to the detected signal. This process has historically been challenging when defining IgE expressing B cells or IgE expressing antibody-secreting cells due to widespread expression of receptors for IgE on various leukocyte subsets, including human B cells. Here we describe our implementation of intracellular staining for human IgE following a blocking step to negate the challenge of surface-bound IgE. We also describe our experience with a human B cell culture system that can be used to robustly validate this approach before application to primary human samples. Orthogonal confirmatory techniques remain essential; these are not described in detail, but several possible strategies are suggested.
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Citometría de Flujo , Inmunoglobulina E , Inmunofenotipificación , Humanos , Citometría de Flujo/métodos , Inmunoglobulina E/inmunología , Inmunoglobulina E/metabolismo , Inmunofenotipificación/métodos , Subgrupos de Linfocitos B/metabolismo , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/citología , Receptores de IgE/metabolismo , Linaje de la Célula/inmunología , Linfocitos B/inmunología , Linfocitos B/metabolismo , Linfocitos B/citologíaRESUMEN
Intracellular flow cytometry is a powerful technique that can be used to interrogate signalling in rare cellular populations. The strengths of the technique are that massively parallel readouts can be gained from thousands of single cells simultaneously, and the assay is fast and relatively straightforward. This plate-based protocol enables different doses and different timepoints of stimulation to be assessed and has been optimized for rare B cell populations. Combining this technique with high-dimensional flow cytometry enables multiple signalling proteins to be measured with high confidence.
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Citometría de Flujo , Células Plasmáticas , Transducción de Señal , Citometría de Flujo/métodos , Células Plasmáticas/metabolismo , Células Plasmáticas/inmunología , Células Plasmáticas/citología , Humanos , Células B de Memoria/metabolismo , Células B de Memoria/inmunología , Animales , Subgrupos de Linfocitos B/metabolismo , Subgrupos de Linfocitos B/inmunologíaRESUMEN
Lung adenocarcinoma (LUAD) is the most prevalent subtype of lung cancer, and the early detection and diagnosis of this disease are crucial in reducing mortality rates. The timely diagnosis of LUAD is essential for controlling tumour development and enabling early surgical treatment. GPR56 is a vital G protein-coupled receptor and its role in T lymphocytes has received considerable attention. However, its function in B cells remains unclear. This study aimed to investigate the significance of GPR56 in LUAD. We found that GPR56 exhibited a significant increase in circulating plasmablasts and a decrease in new memory B cells. GPR56 expression in B cells was significantly reduced after LPS stimulation and the proportion of HLA-DR+ and CD40+ proportions were also decreased in GPR56+ B cells after stimulation. Additionally, GPR56 exhibited significant down-regulation in circulating B cell subsets of early-stage LUAD patients, and there were significant correlations between GPR56+ B cell subsets and tumour markers. In conclusion, GPR56 could reflect the hypoactivation state of B cells and the decreased proportion of GPR56+ B cell subset in LUAD patients can signify the active humoral immunity in vivo. The expression of GPR56 in B cells could potentially hold value in the early diagnosis of LUAD.
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Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Receptores Acoplados a Proteínas G , Humanos , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Adenocarcinoma del Pulmón/inmunología , Adenocarcinoma del Pulmón/metabolismo , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/patología , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Femenino , Anciano , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Activación de Linfocitos , Regulación hacia Abajo , Estadificación de Neoplasias , Inmunidad Humoral , Biomarcadores de Tumor/metabolismoRESUMEN
Despite presenting a worse prognosis and being associated with highly aggressive tumors, triple-negative breast cancer (TNBC) is characterized by the higher frequency of tumor-infiltrating lymphocytes, which have been implicated in better overall survival and response to therapy. Though recent studies have reported the capacity of B lymphocytes to recognize overly-expressed normal proteins, and tumor-associated antigens, how tumor development potentially modifies B cell response is yet to be elucidated. Our findings reveal distinct effects of 4T1 and E0771 murine tumor development on B cells in secondary lymphoid organs. Notably, we observe a significant expansion of total B cells and plasma cells in the tumor-draining lymph nodes (tDLNs) as early as 7 days after tumor challenge in both murine models, whereas changes in the spleen are less pronounced. Surprisingly, within the tumor microenvironment (TME) of both models, we detect distinct B cell subpopulations, but tumor development does not appear to cause major alterations in their frequency over time. Furthermore, our investigation into B cell regulatory phenotypes highlights that the B10 Breg phenotype remains unaffected in the evaluated tissues. Most importantly, we identified an increase in CD19 + LAG-3 + cells in tDLNs of both murine models. Interestingly, although CD19 + LAG-3 + cells represent a minor subset of total B cells (< 3%) in all evaluated tissues, most of these cells exhibit elevated expression of IgD, suggesting that LAG-3 may serve as an activation marker for B cells. Corroborating with these findings, we detected distinct cell cycle and proliferation genes alongside LAG-3 analyzing scRNA-Seq data from a cohort of TNBC patients. More importantly, our study suggests that the presence of LAG-3 B cells in breast tumors could be associated with a good prognosis, as patients with higher levels of LAG-3 B cell transcripts had a longer progression-free interval (PFI). This novel insight could pave the way for targeted therapies that harness the unique properties of LAG-3 + B cells, potentially offering new avenues for improving patient outcomes in TNBC. Further research is warranted to unravel the mechanistic pathways of these cells and to validate their prognostic value in larger, diverse patient cohorts.
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Neoplasias de la Mama Triple Negativas , Microambiente Tumoral , Animales , Neoplasias de la Mama Triple Negativas/patología , Neoplasias de la Mama Triple Negativas/inmunología , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/genética , Femenino , Ratones , Microambiente Tumoral/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Línea Celular Tumoral , Proteína del Gen 3 de Activación de Linfocitos , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Antígenos CD/metabolismo , Linfocitos B/inmunología , Linfocitos B/metabolismo , Ganglios Linfáticos/patología , Bazo/inmunología , Bazo/metabolismo , Bazo/patología , Ratones Endogámicos BALB CRESUMEN
B-1a cells, an innate-like cell population, are crucial for pathogen defense and the regulation of inflammation through their release of natural IgM and IL-10. In sepsis, B-1a cell numbers are decreased in the peritoneal cavity as they robustly migrate to the spleen. Within the spleen, migrating B-1a cells differentiate into plasma cells, leading to alterations in their original phenotype and functionality. We discovered a key player, sialic acid-binding immunoglobulin-like lectin-G (Siglec-G), which is expressed predominantly on B-1a cells and negatively regulates B-1a cell migration to maintain homeostasis. Siglec-G interacts with CXCR4/CXCL12 to modulate B-1a cell migration. Neutrophils aid B-1a cell migration via neutrophil elastase (NE)-mediated Siglec-G cleavage. Human studies revealed increased NE expression in septic patients. We identified an NE cleavage sequence in silico, leading to the discovery of a decoy peptide that protects Siglec-G, preserves peritoneal B-1a cells, reduces inflammation, and enhances sepsis survival. The role of Siglec-G in inhibiting B-1a cell migration to maintain their inherent phenotype and function is compromised by NE in sepsis, offering valuable insights into B-1a cell homeostasis. Employing a small decoy peptide to prevent NE-mediated Siglec-G cleavage has emerged as a promising strategy to sustain peritoneal B-1a cell homeostasis, alleviate inflammation, and ultimately improve outcomes in sepsis patients.
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Homeostasis , Neutrófilos , Sepsis , Lectinas Similares a la Inmunoglobulina de Unión a Ácido Siálico , Sepsis/inmunología , Animales , Humanos , Lectinas Similares a la Inmunoglobulina de Unión a Ácido Siálico/metabolismo , Neutrófilos/inmunología , Neutrófilos/metabolismo , Movimiento Celular , Ratones , Ratones Endogámicos C57BL , Elastasa de Leucocito/metabolismo , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Receptores de Antígenos de Linfocitos BRESUMEN
Fat is stored in distinct depots with unique features in both mice and humans and B cells reside in all adipose depots. We have shown that B cells modulate cardiometabolic disease through activities in two of these key adipose depots: visceral adipose tissue (VAT) and perivascular adipose tissue (PVAT). VAT refers to the adipose tissue surrounding organs, within the abdomen and thorax, and is comprised predominantly of white adipocytes. This depot has been implicated in mediating obesity-related dysmetabolism. PVAT refers to adipose tissue surrounding major arteries. It had long been thought to exist to provide protection and insulation for the vessel, yet recent work demonstrates an important role for PVAT in harboring immune cells, promoting their function and regulating the biology of the underlying vessel. The role of B-2 cells and adaptive immunity in adipose tissue biology has been nicely reviewed elsewhere. Given that, the predominance of B-1 cells in adipose tissue at homeostasis, and the emerging role of B-1 cells in a variety of disease states, we will focus this review on how B-1 cells function in VAT and PVAT depots to promote homeostasis and limit inflammation linked to cardiometabolic disease and factors that regulate this function.
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Tejido Adiposo , Inmunidad Innata , Inflamación , Humanos , Animales , Inflamación/inmunología , Inflamación/metabolismo , Tejido Adiposo/metabolismo , Tejido Adiposo/inmunología , Enfermedades Cardiovasculares/inmunología , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/metabolismo , Obesidad/inmunología , Obesidad/metabolismo , Grasa Intraabdominal/metabolismo , Grasa Intraabdominal/inmunología , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Enfermedades Metabólicas/inmunología , Enfermedades Metabólicas/metabolismo , Enfermedades Metabólicas/etiología , InmunomodulaciónRESUMEN
OBJECTIVES: Autoreactive B cells and interferon (IFN) signature are hallmarks of primary sjögren's syndrome (pSS), but how IFN signaling pathways influence autoantibody production and clinical manifestations remain unclear. More detailed studies hold promise for improved diagnostic methodologies and personalized treatment. METHODS: We analyzed peripheral blood T and B cell subsets from 34 pSS patients and 38 healthy donors (HDs) at baseline and upon stimulation regarding their expression levels of type I and II IFN signaling molecules (STAT1/2, IRF1, IRF9). Additionally, we investigated how the levels of these molecules correlated with serological and clinical characteristics and performed ROC analysis. RESULTS: Patients showed elevated IFN pathway molecules, including STAT1, STAT2 and IRF9 among most T and B cell subsets. We found a reduced ratio of phosphorylated STAT1 and STAT2 in patients in comparison to HDs, although B cells from patients were highly responsive by increased phosphorylation upon IFN stimulation. Correlation matrices showed further interrelations between STAT1, IRF1 and IRF9 in pSS. Levels of STAT1 and IRF9 in T and B cells correlated with the IFN type I marker Siglec-1 (CD169) on monocytes. High levels of STAT1 and IRF9 within pSS B cells were significantly associated with hypergammaglobulinemia as well as anti-SSA/anti-SSB autoantibodies. Elevated STAT1 levels were found in patients with extraglandular disease and could serve as a biomarker for this subgroup (p < 0.01). Notably, IRF9 levels in T and B cells correlated with EULAR Sjögren's syndrome disease activity index (ESSDAI). CONCLUSION: Here, we provide evidence that in active pSS patients, enhanced IFN signaling incl. unphosphorylated STAT1 and STAT2 with IRFs entertain chronic T and B cell activation. Furthermore, increased STAT1 levels candidate as biomarker of extraglandular disease, while IRF9 levels can serve as biomarker for disease activity.
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Biomarcadores , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón , Factor de Transcripción STAT1 , Síndrome de Sjögren , Humanos , Síndrome de Sjögren/inmunología , Síndrome de Sjögren/diagnóstico , Síndrome de Sjögren/metabolismo , Factor de Transcripción STAT1/metabolismo , Femenino , Fosforilación , Persona de Mediana Edad , Masculino , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón/metabolismo , Anciano , Adulto , Linfocitos B/inmunología , Linfocitos B/metabolismo , Autoanticuerpos/inmunología , Autoanticuerpos/sangre , Transducción de Señal , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Lectina 1 Similar a Ig de Unión al Ácido Siálico/metabolismo , Linfocitos T/inmunología , Linfocitos T/metabolismoRESUMEN
Introduction: B cells play a pivotal role in adaptive immunity which has been extensively characterised primarily via flow cytometry-based gating strategies. This study addresses the discrepancies between flow cytometry-defined B cell subsets and their high-confidence molecular signatures using single-cell multi-omics approaches. Methods: By analysing multi-omics single-cell data from healthy individuals and patients across diseases, we characterised the level and nature of cellular contamination within standard flow cytometric-based gating, resolved some of the ambiguities in the literature surrounding unconventional B cell subsets, and demonstrated the variable effects of flow cytometric-based gating cellular heterogeneity across diseases. Results: We showed that flow cytometric-defined B cell populations are heterogenous, and the composition varies significantly between disease states thus affecting the implications of functional studies performed on these populations. Importantly, this paper draws caution on findings about B cell selection and function of flow cytometric-sorted populations, and their roles in disease. As a solution, we developed a simple tool to identify additional markers that can be used to increase the purity of flow-cytometric gated immune cell populations based on multi-omics data (AlliGateR). Here, we demonstrate that additional non-linear CD20, CD21 and CD24 gating can increase the purity of both naïve and memory populations. Discussion: These findings underscore the need to reconsider B cell subset definitions within the literature and propose leveraging single-cell multi-omics data for refined characterisation. We show that single-cell multi-omics technologies represent a powerful tool to bridge the gap between surface marker-based annotations and the intricate molecular characteristics of B cell subsets.
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Subgrupos de Linfocitos B , Citometría de Flujo , Análisis de la Célula Individual , Humanos , Citometría de Flujo/métodos , Análisis de la Célula Individual/métodos , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Linfocitos B/inmunología , Linfocitos B/metabolismo , Inmunofenotipificación/métodos , Biomarcadores , MultiómicaRESUMEN
B cells are important in tuberculosis (TB) immunity, but their role in the human lung is understudied. Here, we characterize B cells from lung tissue and matched blood of patients with TB and found they are decreased in the blood and increased in the lungs, consistent with recruitment to infected tissue, where they are located in granuloma associated lymphoid tissue. Flow cytometry and transcriptomics identify multiple B cell populations in the lung, including those associated with tissue resident memory, germinal centers, antibody secretion, proinflammatory atypical B cells, and regulatory B cells, some of which are expanded in TB disease. Additionally, TB lungs contain high levels of Mtb-reactive antibodies, specifically IgM, which promotes Mtb phagocytosis. Overall, these data reveal the presence of functionally diverse B cell subsets in the lungs of patients with TB and suggest several potential localized roles that may represent a target for interventions to promote immunity or mitigate immunopathology.
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Linfocitos B , Humanos , Linfocitos B/inmunología , Pulmón/inmunología , Pulmón/microbiología , Pulmón/patología , Mycobacterium tuberculosis/inmunología , Mycobacterium tuberculosis/fisiología , Fenotipo , Tuberculosis/inmunología , Tuberculosis/microbiología , Tuberculosis Pulmonar/inmunología , Tuberculosis Pulmonar/patología , Tuberculosis Pulmonar/microbiología , Tuberculosis Pulmonar/genética , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Masculino , Femenino , AdultoRESUMEN
Autoimmune hepatitis (AIH) is a chronic, inflammatory liver disease of unknown aetiology which requires lifelong immunosuppression. Most therapeutic and outcome studies of AIH have been conducted predominantly in Caucasian (European Ancestry, EA) cohorts, with the exclusion of African American (AA) patients due to inadequate sample size. It is known that AA patients have a severe phenotype of autoimmune diseases and demonstrate a poor response to conventional medical therapy. Understanding cellular and molecular pathways which determine AIH severity and progression in AA patients is likely to lead to the discovery of novel, personalised and better tolerated therapies. The aim of the study is to determine the distinct effector B cell phenotypes which contribute to disease severity and progression of AIH in AA children as compared to their EA cohorts. PBMCs were isolated from blood samples collected from patients visiting Children's Healthcare of Atlanta (CHOA) and were grouped into AA, (n = 12), EA, (n = 11) and controls (n = 12) and were processed for flow cytometry. Markers of B cell development, maturation and activation were assessed namely CD19, CD21, IgD, CD27, CD38, CD11c, CD24, CD138. AA children with AIH demonstrated an expansion of CD19 + ve, Activated Naïve (aN), (CD19+ IgD-/CD27- Double Negative (DN2) ([CD19+/IgD-/CD27++CD38++) cells. Plasmablasts were significantly higher along with Signalling Lymphocytic activation molecule F7 (SLAMF7). Unswitched memory [CD19+] IgD+CD27+ (USM) B cells were significantly contracted in AA patients with AIH. B cell phenotyping reveals a distinct profile in AA AIH patients with a major skewing towards the expansion of effector pathways which have been previously characterised in severe SLE in AA patients. These results suggest that the quantification and therapeutic target of B cell pathway could contribute substantially to the clinical approach to AIH especially in the AA population.
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Linfocitos B , Hepatitis Autoinmune , Inmunoglobulina D , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral , Humanos , Hepatitis Autoinmune/inmunología , Hepatitis Autoinmune/sangre , Hepatitis Autoinmune/patología , Hepatitis Autoinmune/diagnóstico , Inmunoglobulina D/inmunología , Inmunoglobulina D/metabolismo , Niño , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/metabolismo , Masculino , Femenino , Adolescente , Linfocitos B/inmunología , Linfocitos B/metabolismo , Preescolar , Inmunofenotipificación , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Edad de Inicio , BiomarcadoresRESUMEN
Recent studies have demonstrated a role for Ten-Eleven Translocation-2 (TET2), an epigenetic modulator, in regulating germinal center formation and plasma cell differentiation in B-2 cells, yet the role of TET2 in regulating B-1 cells is largely unknown. Here, B-1 cell subset numbers, IgM production, and gene expression were analyzed in mice with global knockout of TET2 compared to wildtype (WT) controls. Results revealed that TET2-KO mice had elevated numbers of B-1a and B-1b cells in their primary niche, the peritoneal cavity, as well as in the bone marrow (B-1a) and spleen (B-1b). Consistent with this finding, circulating IgM, but not IgG, was elevated in TET2-KO mice compared to WT. Analysis of bulk RNASeq of sort purified peritoneal B-1a and B-1b cells revealed reduced expression of heavy and light chain immunoglobulin genes, predominantly in B-1a cells from TET2-KO mice compared to WT controls. As expected, the expression of IgM transcripts was the most abundant isotype in B-1 cells. Yet, only in B-1a cells there was a significant increase in the proportion of IgM transcripts in TET2-KO mice compared to WT. Analysis of the CDR3 of the BCR revealed an increased abundance of replicated CDR3 sequences in B-1 cells from TET2-KO mice, which was more clearly pronounced in B-1a compared to B-1b cells. V-D-J usage and circos plot analysis of V-J combinations showed enhanced usage of VH11 and VH12 pairings. Taken together, our study is the first to demonstrate that global loss of TET2 increases B-1 cell number and IgM production and reduces CDR3 diversity, which could impact many biological processes and disease states that are regulated by IgM.
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Subgrupos de Linfocitos B , Ratones , Animales , Subgrupos de Linfocitos B/metabolismo , Linfocitos B , Cadenas Ligeras de Inmunoglobulina/genética , Translocación Genética , Inmunoglobulina M , Recuento de CélulasRESUMEN
BACKGROUND: The widespread involvement of tumor-infiltrating B cells highlights their potential role in tumor behavior. However, B cell heterogeneity in PDAC remains unexplored. Studying TIL-Bs in PDAC aims to identify new treatment strategies. METHODS: We performed single-cell RNA sequencing to study the heterogeneity of B cells in PDAC. The prognostic and immunologic value of the identified CD38+ B cells was explored in FUSCC (n = 147) and TCGA (n = 176) cohorts. Flow cytometry was conducted to characterize the relationship between CD38+ B cells and other immune cells, as well as their phenotypic features. In vitro and in vivo experiments were performed to assess the putative effect of CD38+ B cells on antitumor immunity. FINDINGS: The presence of CD38+ B cells in PDAC was associated with unfavorable clinicopathological features and poorer overall survival (p < 0.001). Increased infiltration of CD38+ B cells was accompanied by reduced natural killer (NK) cells (p = 0.021) and increased regulatory T cells (p = 0.016). Molecular profiling revealed high expression of IL-10, IL-35, TGF-ß, GZMB, TIM-1, CD5 and CD21, confirming their putative regulatory B cell-like features. Co-culture experiments demonstrated suppression of NK cell cytotoxicity by CD38+ B cell-derived IL-10 (p < 0.001). Finally, in vivo experiments suggested adoptive transfer of CD38+ B cells reduced antitumor immunity and administration of a CD38 inhibitor hampered tumor growth (p < 0.001). INTERPRETATION: We discovered regulatory B cell-like CD38+ B cell infiltration as an independent prognostic factor in PDAC. The use of CD38 inhibitor may provide new possibilities for PDAC immunotherapy. FUNDING: This study was supported by the National Natural Science Foundation of China (U21A20374), Shanghai Municipal Science and Technology Major Project (21JC1401500), Scientific Innovation Project of Shanghai Education Committee (2019-01-07-00-07-E00057), Special Project for Clinical Research in the Health Industry of the Shanghai Health Commission (No. 20204Y0265) and Natural Science Foundation of Shanghai (23ZR1479300).
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ADP-Ribosil Ciclasa 1 , Carcinoma Ductal Pancreático , Humanos , ADP-Ribosil Ciclasa 1/metabolismo , Carcinoma Ductal Pancreático/inmunología , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/mortalidad , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/terapia , Animales , Ratones , Pronóstico , Antígenos CD19/metabolismo , Antígenos CD19/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/mortalidad , Femenino , Masculino , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/genética , Línea Celular Tumoral , Microambiente Tumoral/inmunología , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Linfocitos B/inmunología , Linfocitos B/metabolismo , Persona de Mediana Edad , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Terapia de InmunosupresiónRESUMEN
Idiopathic inflammatory myopathies are a heterogeneous group of rare autoimmune disorders characterized by progressive muscle weakness and the histopathologic findings of inflammatory infiltrates in muscle tissue. Although their pathogenesis remains indefinite, the association of autoantibodies with clinical manifestations and the evidence of high effectiveness of depleting therapies suggest that B cells could be implicated. Therefore, we explored the landscape of peripheral B cells in this disease by multiparametric flow cytometry, finding significant numerical decreases in memory and double-negative subsets, as well as an expansion of the naive compartment relative to healthy controls, that contribute to defining disease-associated B-cell subset signatures and correlating with different clinical features of patients. Additionally, we determined the potential value of these subsets as diagnostic biomarkers, thus positioning B cells as neglected key elements possibly participating in idiopathic inflammatory myopathy onset or development.
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Subgrupos de Linfocitos B , Biomarcadores , Miositis , Humanos , Miositis/inmunología , Miositis/patología , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Femenino , Masculino , Persona de Mediana Edad , Adulto , Anciano , Citometría de FlujoRESUMEN
Chronic inflammatory demyelinating polyneuropathy (CIDP), a common and treatable autoimmune neuropathy, is frequently misdiagnosed. The aim of this study is to evaluate the relationship between immunological markers and clinical outcome measures in a mixed cohort of patients with typical CIDP and CIDP variants at different disease stages. Twenty-three typical, 16 multifocal and five distal CIDP patients were included. Twenty-five sex and age-matched healthy controls and 12 patients with Charcot-Marie-Tooth type 1A (CMT1A) disease served as controls. Peripheral B-cell populations were analyzed by flow cytometry. IL6, IL10, TNFA mRNA and mir-21, mir-146a, and mir-155-5p expression levels were evaluated by real-time polymerase chain reaction in peripheral blood mononuclear cells (PBMC) and/or skin biopsy specimens. Results were then assessed for a possible association with clinical disability scores and intraepidermal nerve fiber densities (IENFD) in the distal leg. We detected a significant reduction in naive B cells (Pâ ≤â 0.001), plasma cells (Pâ ≤â 0.001) and regulatory B cells (Pâ <â 0.05), and an elevation in switched memory B cells (Pâ ≤â 0.001) in CIDP compared to healthy controls. CMT1A and CIDP patients had comparable B-cell subset distribution. CIDP cases had significantly higher TNFA and IL10 gene expression levels in PBMC compared to healthy controls (Pâ <â 0.05 and Pâ ≤â 0.01, respectively). IENFDs in the distal leg showed a moderate negative correlation with switched memory B-cell ratios (râ =â -0.51, Pâ <â 0.05) and a moderate positive correlation with plasma cell ratios (râ =â 0.46, Pâ <â 0.05). INCAT sum scores showed a moderate positive correlation with IL6 gene expression levels in PBMC (râ =â 0.54, Pâ <â 0.05). Altered B-cell homeostasis and IL10 and TNFA gene expression levels imply chronic antigen exposure and overactivity in the humoral immune system, and seem to be a common pathological pathway in both typical CIDP and CIDP variants.
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Subgrupos de Linfocitos B , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante , Humanos , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante/genética , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante/diagnóstico , Leucocitos Mononucleares/metabolismo , Citocinas/genética , Subgrupos de Linfocitos B/metabolismo , Interleucina-10/genética , Interleucina-6/genéticaRESUMEN
During B cell maturation, transitional and mature B cells acquire cell-intrinsic features that determine their ability to exit quiescence and mount effective immune responses. Here we use label-free proteomics to quantify the proteome of B cell subsets from the mouse spleen and map the differential expression of environmental sensing, transcription, and translation initiation factors that define cellular identity and function. Cross-examination of the full-length transcriptome and proteome identifies mRNAs related to B cell activation and antibody secretion that are not accompanied by detection of the encoded proteins. In addition, proteomic data further suggests that the translational repressor PDCD4 restrains B cell responses, in particular those from marginal zone B cells, to a T-cell independent antigen. In summary, our molecular characterization of B cell maturation presents a valuable resource to further explore the mechanisms underpinning the specialized functions of B cell subsets, and suggest the presence of 'poised' mRNAs that enable expedited B cell responses.
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Subgrupos de Linfocitos B , Linfocitos B , Linfocitos B/citología , Linfocitos B/metabolismo , Proteoma , Transcriptoma , Animales , Ratones , Diferenciación Celular , Factores de Transcripción/metabolismo , ARN Mensajero , Biosíntesis de Proteínas , Subgrupos de Linfocitos B/metabolismoRESUMEN
Although therapeutic B cell depletion dramatically resolves inflammation in many diseases in which antibodies appear not to play a central role, distinct extrafollicular pathogenic B cell subsets that accumulate in disease lesions have hitherto not been identified. The circulating immunoglobulin D (IgD)-CD27-CXCR5-CD11c+ DN2 B cell subset has been previously studied in some autoimmune diseases. A distinct IgD-CD27-CXCR5-CD11c- DN3 B cell subset accumulates in the blood both in IgG4-related disease, an autoimmune disease in which inflammation and fibrosis can be reversed by B cell depletion, and in severe COVID-19. These DN3 B cells prominently accumulate in the end organs of IgG4-related disease and in lung lesions in COVID-19, and double-negative B cells prominently cluster with CD4+ T cells in these lesions. Extrafollicular DN3 B cells may participate in tissue inflammation and fibrosis in autoimmune fibrotic diseases, as well as in COVID-19.
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Subgrupos de Linfocitos B , COVID-19 , Enfermedad Relacionada con Inmunoglobulina G4 , Humanos , Fibrosis , Inmunoglobulina D , Inflamación , Receptores CXCR5 , Subgrupos de Linfocitos B/metabolismo , Subgrupos de Linfocitos B/patologíaRESUMEN
Autoantibodies produced by B cells play a pivotal role in the pathogenesis of systemic lupus erythematosus (SLE). However, both the cellular source of antiphospholipid antibodies and their contributions to the development of lupus nephritis (LN) remain largely unclear. Here, we report a pathogenic role of anti-phosphatidylserine (PS) autoantibodies in the development of LN. Elevated serum PS-specific IgG levels were measured in model mice and SLE patients, especially in those with LN. PS-specific IgG accumulation was found in the kidney biopsies of LN patients. Both transfer of SLE PS-specific IgG and PS immunization triggered lupus-like glomerular immune complex deposition in recipient mice. ELISPOT analysis identified B1a cells as the main cell type that secretes PS-specific IgG in both lupus model mice and patients. Adoptive transfer of PS-specific B1a cells accelerated the PS-specific autoimmune response and renal damage in recipient lupus model mice, whereas depletion of B1a cells attenuated lupus progression. In culture, PS-specific B1a cells were significantly expanded upon treatment with chromatin components, while blockade of TLR signal cascades by DNase I digestion and inhibitory ODN 2088 or R406 treatment profoundly abrogated chromatin-induced PS-specific IgG secretion by lupus B1a cells. Thus, our study has demonstrated that the anti-PS autoantibodies produced by B1 cells contribute to lupus nephritis development. Our findings that blockade of the TLR/Syk signaling cascade inhibits PS-specific B1-cell expansion provide new insights into lupus pathogenesis and may facilitate the development of novel therapeutic targets for the treatment of LN in SLE.