Details for: CL0000785

Cell ID: CL0000785

Cell Name: mature B cell

Description: Mature B cells are also reportedly CD10-negative, CD19-positive, CD22-positive, CD34-negative, CD48-positive, CD79a-positive, CD84-positive, CD127-negative, CD352-positive, RAG-negative, TdT-negative, Vpre-B-negative, and pre-BCR-negative. Transcription factors expressed: Pax5-positive.

Synonyms: mature B lymphocyte, mature B-cell, mature B-lymphocyte

Selected Context(s): Overall

Gene Significance Landscape

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Genes

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Cell Significance Index (CSI) is uniquely calculated to reveal cell-specific gene markers. More info here

Significant Genes List

Genes with the highest and lowest Percentile Rank Scores (PRS) for mature B cell within the selected context(s).

Gene ID: A unique numerical identifier for this specific gene.
Symbol: Shortened abbreviation or name that represents this gene.
Ensembl Gene ID: A unique identifier assigned by Ensembl for genomic data mapping.
CSI Score: A combined effect size and statistical significance measure for mature B cell. Higher scores indicate a stronger, more significant difference in expression.
(Previously described as "Fold Change", but now represents Cliff's Delta × –log10(p).)

Gene ID: A unique numerical identifier for this specific gene.
Symbol: Shortened abbreviation or name that represents this gene.
Ensembl Gene ID: A unique identifier assigned by Ensembl for genomic data mapping.
CSI Score: A combined effect size and statistical significance measure for mature B cell. Higher scores indicate a stronger, more significant difference in expression.
Average CSI: csi sum / gene count
Cell network configuration

This network visualizes key genes for mature B cell. It primarily includes:
1. Top genes highly significant for this cell (Num. Top Cell Genes - based on the 'Min. CSI' setting).
2. Any additional specific 'Context Genes' you add below.
The final network is a combined view. Choose an Interaction Source (pathways or protein interactions) and optionally compare CSI scores with a Baseline Cell Type.

Maximum number of selected genes.
Select a context for the baseline cell.
Select a context for the target cell.
Target Cell for CSI:  mature B cell (CL0000785)

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Nodes (Genes):
 Query Gene
Node size also reflects Target Cell CSI magnitude.
Node Color (Target Cell CSI in specific network):
 Very High
 High
 Medium
 Low
 Very Low
 N/A or Not Sig.
Edges (Interactions):
 STRING (Protein-Protein)
 ONTOLOGY (Shared Pathway)
 Colors vary by pathway category; default arrow applies.

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## Summary The [mature B cell](/details-cell/CL0000785) is a key component of the adaptive immune system, phenotypically characterized as CD19-positive, CD22-positive, and Pax5-positive, while lacking markers of immaturity such as CD10, RAG, and TdT. Gene significance analysis reveals that the identity of this cell type is overwhelmingly defined by a profound and highly specific expression of genes related to core metabolic and biosynthetic processes. The top markers are dominated by components of mitochondrial respiratory chains and protein translation machinery, suggesting that [mature B cells](/details-cell/CL0000785) maintain a state of high metabolic readiness. This "primed" state is likely essential for their fundamental capacity to rapidly differentiate and execute large-scale antibody production upon antigen encounter. ## Key Characteristics and Function **Overall**, the gene expression landscape of the [mature B cell](/details-cell/CL0000785) underscores its role as a metabolically active and biosynthetically capable immune effector. The most significant genes can be grouped into distinct functional clusters that together define its cellular identity and function. * **Mitochondrial Energy Production:** A striking number of the top-ranking markers are involved in oxidative phosphorylation. This includes multiple subunits of the cytochrome c oxidase complex ([COX1](/details-gene/4512), [COX2](/details-gene/4513), [COX4I1](/details-gene/1327), [CYTB](/details-gene/4519)), ATP synthase ([ATP5MC2](/details-gene/517), [ATP5F1E](/details-gene/514), [ATP6](/details-gene/4508)), and the mitochondrial ADP/ATP translocator ([SLC25A6](/details-gene/293)). The high specificity scores ([csi_z](/glossary/csi_z)) for these genes indicate that this intense mitochondrial activity is a uniquely defining feature of [mature B cells](/details-cell/CL0000785) compared to other cell types, providing the substantial energy required for immune readiness and eventual antibody synthesis. * **Protein Synthesis and Regulation:** Complementing the high energy capacity is a robust machinery for protein production. Top markers include translation elongation factors ([EEF1D](/details-gene/1936), [EEF1B2](/details-gene/1933)) and the poly(A)-binding protein ([PABPC1](/details-gene/26986)), which are critical for efficient translation. The high significance of [TPT1](/details-gene/7178), a translationally controlled tumor protein, further points to tight regulation of protein synthesis, a hallmark of cells poised for massive production of a specific protein product like immunoglobulins. * **Immune Surveillance and Interaction:** The highest-ranking marker, [B2M](/details-gene/567) (Beta-2-microglobulin), is an essential component of MHC class I molecules, underscoring the B cell's role as an antigen-presenting cell (APC) to CD8+ T cells. Additionally, the high specificity of the non-classical MHC molecule [HLA-E](/details-gene/3133) suggests a specialized function in modulating innate immune responses, possibly through interactions with NK cell inhibitory receptors. * **RNA Processing and Cytoskeletal Dynamics:** Genes involved in RNA metabolism, such as [HNRNPA2B1](/details-gene/3181) and [NPM1](/details-gene/4869), highlight the extensive post-transcriptional regulation required to manage the B cell transcriptome. The actin-depolymerizing factor [CFL1](/details-gene/1072) points to the importance of cytoskeletal remodeling, which is crucial for cell motility, trafficking through lymphoid organs, and forming the immunological synapse during antigen presentation. * **Defining Negative Markers:** The anti-marker list provides critical context for what this cell is not. The very low significance of the T-cell receptor alpha constant gene, [TRAC](/details-gene/28755), definitively confirms the cell's B lymphocyte lineage. The low specificity score for the B cell homing receptor [CXCR5](/details-gene/643) is unexpected, as this is a canonical B cell marker. This suggests that while [CXCR5](/details-gene/643) is expressed, its expression level is not as uniquely specific to [mature B cells](/details-cell/CL0000785) when compared across a diverse cellular landscape in this dataset, possibly due to its expression on other cell types like follicular helper T cells. ## Clinical Significance and Contextual Roles While this analysis is based on a general context, the key markers of the [mature B cell](/details-cell/CL0000785) have significant clinical implications. The profound metabolic signature is highly relevant to B cell malignancies. Cancers like Burkitt's lymphoma, mentioned in the literature for [CXCR5](/details-gene/643) ([Link](https://doi.org/10.1002/eji.1830221107)), are characterized by rapid proliferation, which undoubtedly relies on the high-capacity energy and biosynthetic pathways highlighted here. Targeting these metabolic vulnerabilities could represent a therapeutic strategy. The top marker, [B2M](/details-gene/567), has direct clinical relevance. Soluble B2M is a prognostic marker in several lymphoid neoplasms, including multiple myeloma and chronic lymphocytic leukemia. Furthermore, mutations in [B2M](/details-gene/567) are a known mechanism of immune evasion in cancer, as its loss prevents the assembly and surface expression of MHC class I molecules, rendering tumor cells invisible to cytotoxic T lymphocytes. Several other top markers are implicated in disease. [NPM1](/details-gene/4869) is frequently mutated in acute myeloid leukemia, and while this is a different hematopoietic lineage, it underscores the gene's critical role in hematopoiesis and its potential for oncogenic transformation ([Link](https://doi.org/10.1021/bi00429a017)). The expression of [HLA-E](/details-gene/3133) on tumor cells can also contribute to immune escape by engaging inhibitory receptors on NK cells and T cells. ## Potential Mechanisms and Research Directions 1. **Hypothesis:** The gene signature suggests that [mature B cells](/details-cell/CL0000785) exist in a "metabolically primed" state. Unlike quiescent cells that ramp up metabolism upon activation, these cells may constitutively maintain high levels of mitochondrial and translational machinery as a defining feature of their lineage. This pre-established capacity could be a critical factor determining the speed and magnitude of the primary humoral immune response. * **Surprising Findings:** The dominance of fundamental "housekeeping" genes (related to metabolism and translation) as the most specific markers is striking. It implies these processes are not merely supportive but are a core, uniquely defining aspect of the mature B cell identity in a broad cellular context. The low specificity score of [CXCR5](/details-gene/643), a well-established B cell homing receptor, is particularly notable and suggests its utility as a unique identifier may be limited in diverse transcriptomic datasets. * **Testable Questions:** How does the mitochondrial reserve capacity and translational rate of naive [mature B cells](/details-cell/CL0000785) compare to that of naive T cells at baseline? Furthermore, does pre-treatment of naive B cells with inhibitors of oxidative phosphorylation or protein synthesis disproportionately blunt their ability to differentiate into antibody-secreting cells upon activation compared to other lymphocyte populations? 2. **Hypothesis:** The concurrent high specificity of [B2M](/details-gene/567) and [HLA-E](/details-gene/3133) suggests that [mature B cells](/details-cell/CL0000785) play a sophisticated, dual role in regulating both adaptive and innate immunity. Beyond their canonical function of presenting peptide antigens via classical MHC-I, they may actively fine-tune the activity of NK cells and subsets of T cells through the regulated expression of [HLA-E](/details-gene/3133), thereby contributing to self-tolerance and shaping the local immune environment within lymphoid tissues. * **Surprising Findings:** While the high expression of [B2M](/details-gene/567) is expected for an APC, the equally high specificity of [HLA-E](/details-gene/3133) is less conventional. This finding proposes that interaction with the innate immune system via non-classical MHC presentation is not an ancillary function but a highly characteristic feature of the mature B cell state. * **Testable Questions:** In a co-culture system with autologous NK cells, how does the surface expression of [HLA-E](/details-gene/3133) on [mature B cells](/details-cell/CL0000785) change in response to different activation signals (e.g., BCR cross-linking vs. TLR stimulation), and does this alteration directly modulate NK cell cytotoxicity and cytokine production?