Details for: CL0000980

Cell ID: CL0000980

Cell Name: plasmablast

Description: This cell type is compatible with the HIPC Lyoplate markers for 'plasmablast'. Plasmablasts are also reportedly CD48-positive, CD63-positive, CD229-positive, CD270-positive, CD319-positive, CD352-positive, CD361-positive, and IgD-negative.

Synonyms: CD20-negative B cell, CD27-positive, CD38-positive, CD20-negative B cell

Selected Context(s): Overall

Gene Significance Landscape

Display Options
Score:
Display
Genes

Contexts:

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 plasmablast 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 plasmablast. 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 plasmablast. 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 plasmablast. 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:  plasmablast (CL0000980)

 Legend
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.

Loading network (please wait)...

## Summary The [plasmablast](/details-cell/CL0000980) is a terminally differentiating, antibody-secreting cell of the B lymphocyte lineage, representing a transitional state between an activated [B cell](/details-cell/CL0000236) and a mature [plasma cell](/details-cell/CL0000786). Characterized by surface markers such as CD27 and CD38 in the absence of CD20, this cell type is defined by an extraordinary commitment to biosynthesis. The gene significance profile, based on expression specificity (**Overall** context), is overwhelmingly dominated by components of mitochondrial energy production and protein synthesis machinery. This suggests that the core identity of a [plasmablast](/details-cell/CL0000980) is that of a metabolic and biosynthetic powerhouse, optimized for the massive production and secretion of immunoglobulins. ## Key Characteristics and Function Analysis of top marker genes, ranked by expression specificity (`csi_z`), reveals a cellular program intensely focused on two interconnected biological processes: energy generation and protein production. * **Mitochondrial Respiration and Energy Metabolism:** A significant majority of the top-ranking markers are components of the mitochondrial electron transport chain and ATP synthase complex. This includes mitochondrial-encoded genes such as [COX2](/details-gene/4513) (CSI: 122.61), [COX1](/details-gene/4512) (CSI: 120.37), [CYTB](/details-gene/4519) (CSI: 109.34), and [ND5](/details-gene/4540) (CSI: 103.26), as highlighted in the complete sequencing of the human mitochondrial genome ([Link](https://doi.org/10.1038/290457a0)). Nuclear-encoded mitochondrial genes are also exceptionally specific markers, including [ATP5MG](/details-gene/10632) (CSI: 117.96), [CHCHD2](/details-gene/51142) (CSI: 113.12), [COX4I1](/details-gene/1327) (CSI: 107.16), [ATP5F1E](/details-gene/514) (CSI: 111.85), and [ATP5MC2](/details-gene/517) (CSI: 104.44). This profound enrichment indicates that the cell's defining characteristic is its massive capacity for aerobic respiration, a necessary adaptation to generate the vast amounts of ATP required for immunoglobulin synthesis, modification, and secretion. * **Protein Synthesis and Processing:** The second major functional cluster consists of genes essential for protein translation and post-translational modification. The high specificity of eukaryotic translation elongation factors [EEF1B2](/details-gene/1933) (CSI: 115.27) and [EEF1D](/details-gene/1936) (CSI: 103.99) points to a high rate of polypeptide chain synthesis. The significant expression of [OST4](/details-gene/100128731) (CSI: 114.91), a subunit of the oligosaccharyltransferase complex required for N-glycosylation ([Link](https://doi.org/10.1242/jcs.115410)), underscores the importance of proper protein modification, a critical step for antibody stability and function. Furthermore, the high specificity of [NPM1](/details-gene/4869) (CSI: 108.11), a nucleolar phosphoprotein involved in ribosome biogenesis, suggests the cell is actively expanding its translational capacity. * **Cellular Maintenance and Stress Response:** Genes such as high-mobility group box 1 ([HMGB1](/details-gene/3146); CSI: 113.05) and beta-2-microglobulin ([B2M](/details-gene/567); CSI: 106.26) are also highly specific. [HMGB1](/details-gene/3146) is a nuclear protein that can be secreted as a damage-associated molecular pattern (DAMP), suggesting [plasmablasts](/details-cell/CL0000980) may have a role in modulating local inflammation. The high level of [B2M](/details-gene/567), a component of MHC class I, likely reflects the high rate of protein turnover and processing through the endoplasmic reticulum. The anti-marker profile is informative. The low specificity scores for numerous immunoglobulin variable region genes (e.g., [IGHV3 21](/details-gene/28444), [IGLV2 8](/details-gene/28817)) are initially counterintuitive. This does not imply a lack of expression but rather that the expression of these gene *segments* is not unique to [plasmablasts](/details-cell/CL0000980) when compared to other B-lineage cells that also express them prior to terminal differentiation. This highlights that the *machinery* for massive protein production, rather than the immunoglobulin genes themselves, is what most uniquely defines the plasmablast state at the transcriptomic level. ## Clinical Significance and Contextual Roles **Overall**, the gene signature of a [plasmablast](/details-cell/CL0000980) positions it as a cell of immense physiological importance during humoral immune responses, but also as a potential contributor to pathology. The cell's profound reliance on oxidative phosphorylation suggests a potential vulnerability. Metabolic inhibitors targeting mitochondrial function could selectively impact [plasmablast](/details-cell/CL0000980) activity and antibody production, a strategy that may be relevant in autoimmune diseases characterized by autoantibody production. Several top markers have direct clinical relevance. [NPM1](/details-gene/4869) is frequently mutated in acute myeloid leukemia, and its high expression is associated with cellular growth and ribosome biogenesis ([Link](https://doi.org/10.1021/bi00429a017)). Its specific expression in [plasmablasts](/details-cell/CL0000980) highlights its role in highly proliferative hematopoietic cells. Similarly, [HMGB1](/details-gene/3146) expression has been linked to differentiation and stage in gastrointestinal adenocarcinomas ([Link](https://doi.org/10.1002/(sici)1097-0215(19970220)74:1<1::aid-ijc1>3.0.co;2-6)), and its role as an inflammatory mediator could implicate [plasmablasts](/details-cell/CL0000980) in the tumor microenvironment or chronic inflammatory diseases. The high expression of [TMBIM6](/details-gene/7009), an anti-apoptotic protein that regulates ER calcium flux and homeostasis, may be a critical survival factor that allows [plasmablasts](/details-cell/CL0000980) to cope with the immense ER stress caused by immunoglobulin overproduction. This makes it a potential therapeutic target in diseases of plasmablast expansion, such as multiple myeloma. ## Potential Mechanisms and Research Directions 1. **Hypothesis: Metabolic Reprogramming as the Master Regulator of Plasmablast Differentiation.** The data suggest that the defining event in becoming a [plasmablast](/details-cell/CL0000980) is a massive and specific upregulation of the entire mitochondrial respiratory apparatus. We hypothesize that this metabolic switch is not merely a consequence of differentiation but is a primary, rate-limiting driver of the cell's biosynthetic capacity and ultimate fate. This metabolic state may also represent a key vulnerability. * **Surprising Findings:** The degree to which mitochondrial gene expression specificity defines this cell type is striking, overshadowing even immunoglobulin genes in the `csi_z` metric. This suggests that from a systems biology perspective, a [plasmablast](/details-cell/CL0000980) is best described as a "mitochondrial cell" that happens to produce antibodies, rather than the other way around. * **Testable Questions:** Does inhibiting key nodes of oxidative phosphorylation, such as cytochrome c oxidase (using inhibitors targeting [COX1](/details-gene/4512)/[COX2](/details-gene/4513)) or ATP synthase (targeting [ATP5MG](/details-gene/10632)), block the differentiation of activated [B cells](/details-cell/CL0000236) into [plasmablasts](/details-cell/CL0000980) and disproportionately reduce their viability compared to less metabolically active lymphocyte populations? 2. **Hypothesis: Pre-emptive Stress Management Enables High-Volume Antibody Production.** The co-expression of machinery for massive protein synthesis ([EEF1B2](/details-gene/1933), [OST4](/details-gene/100128731)) alongside proteins involved in managing cellular stress and protein quality control ([NPM1](/details-gene/4869), [TMBIM6](/details-gene/7009)) suggests that [plasmablasts](/details-cell/CL0000980) exist in a state of "primed" or "managed" ER stress. We hypothesize that this pre-emptive program is essential for survival and function, preventing the terminal activation of the unfolded protein response (UPR) that would otherwise be triggered by the enormous protein load. * **Surprising Findings:** The identification of [TMBIM6](/details-gene/7009), a protein that protects against ER stress-induced apoptosis, as a specific marker is highly significant. It implies that survival is not passive but an actively maintained state, hard-wired into the plasmablast differentiation program to counteract the inherent dangers of its primary function. * **Testable Questions:** Does the targeted knockdown of [TMBIM6](/details-gene/7009) or [NPM1](/details-gene/4869) in [plasmablasts](/details-cell/CL0000980) lead to spontaneous apoptosis or a heightened sensitivity to pharmacological ER stressors, resulting in a significant reduction in immunoglobulin secretion and cell viability?