Details for: CL0000786

Cell ID: CL0000786

Cell Name: plasma cell

Description: Plasma cells develop in the spleen and migrate to the bone marrow. Plasma cells are also reportedly CD5-negative, CD10-negative, CD19-positive, CD20-negative, CD21-negative, CD22-negative, CD23-negative, CD24-negative, CD25-negative, CD27-positive, CD34-negative, CD38-positive, CD40-positive, CD43-positive, CD45-positive, CD48-positive, CD53-low, CD80-negative, CD81-positive, CD86-positive, CD95-positive, CD196-negative, CD229-positive, CD270-positive, CD352-positive, CD361-positive, and IgD-negative. Transcription factors: BLIMP1-positive, IRF4-positive, PAX5-negative, SpiB-negative, Ets1-negative, and XBP1-positive.

Synonyms: effector B cell, effector B-cell, plasma B cell, plasma B-cell, plasmacyte, plasmocyte

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 plasma 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 plasma 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 plasma 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 plasma 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:  plasma cell (CL0000786)

 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 [plasma cell](/details-cell/CL0000786), a terminally differentiated effector [B-cell](/details-cell/CL0000236), is fundamentally defined by its role as a professional antibody-secreting factory. This identity is unequivocally supported by its gene significance profile, which is dominated by genes essential for the synthesis, folding, and secretion of immunoglobulins. **Overall**, the most defining characteristic, as indicated by top-specificity markers ([csi_z](/glossary/csi_z)), is not only the expression of immunoglobulin chains themselves ([JCHAIN](/details-gene/3512), [IGKC](/details-gene/3514)), but also the profound specialization of its endoplasmic reticulum (ER) and metabolic machinery to handle immense proteotoxic stress. The top-ranked gene, [HERPUD1](/details-gene/9709), a key component of the ER stress response, underscores that managing the burden of protein production is as crucial to the plasma cell's identity as the antibodies it produces. ## Key Characteristics and Function The gene significance landscape of the [plasma cell](/details-cell/CL0000786) reveals a highly specialized cellular machine organized around several core functional themes. * **Antibody Synthesis and Assembly:** The cell's canonical function is highlighted by the high specificity scores of genes encoding immunoglobulin components. These include the joining chain ([JCHAIN](/details-gene/3512)), the kappa light chain ([IGKC](/details-gene/3514)), and various heavy chains such as [IGHG1](/details-gene/3500), [IGHG3](/details-gene/3502), and [IGHA1](/details-gene/3493). This signature confirms the cell's role as the primary producer of secreted antibodies in the humoral immune response. * **ER-Associated Protein Processing and Quality Control:** To support the massive output of antibodies, plasma cells exhibit a uniquely specialized protein-handling apparatus. This is evidenced by the top marker, [HERPUD1](/details-gene/9709), which is induced by ER stress and points to a constitutively active unfolded protein response (UPR) pathway ([Link](https://doi.org/10.1074/jbc.m002063200)). This is complemented by other highly specific ER-resident proteins, including [MZB1](/details-gene/51237), which is known to be upregulated during plasma cell differentiation and aids in the oxidative folding of immunoglobulins ([Link](https://doi.org/10.1073/pnas.0811591106)), the prolyl-isomerase [FKBP11](/details-gene/51303), the N-glycosylation subunit [OST4](/details-gene/100128731), and the anti-apoptotic calcium channel regulator [TMBIM6](/details-gene/7009). The high significance of translation elongation factors ([EEF1B2](/details-gene/1933), [EEF1D](/details-gene/1936)) and the polyubiquitin gene [UBC](/details-gene/7316) further illustrates a state of high-level protein synthesis coupled with robust quality control and degradation pathways. * **High Metabolic and Energy Demand:** The synthesis of thousands of antibody molecules per second is an energy-intensive process. This is reflected in the specific expression of numerous genes encoding components of the mitochondrial electron transport chain, such as [COX1](/details-gene/4512), [COX2](/details-gene/4513), [CYTB](/details-gene/4519), and [ND1](/details-gene/4535). The high rank of [FTL](/details-gene/2512), a key iron storage protein, is consistent with the need for iron as a cofactor in many metabolic and respiratory enzymes. * **Antigen Presentation and Immune Interaction:** The significant specificity score for [B2M](/details-gene/567), the light chain of MHC class I molecules, is notable. While not professional antigen-presenting cells, this suggests that plasma cells maintain a robust capacity for presenting endogenous peptides, which may be a mechanism for surveillance and regulation by cytotoxic T lymphocytes. ## Clinical Significance and Contextual Roles The gene signature of [plasma cells](/details-cell/CL0000786) provides direct insight into their role in disease, particularly in plasma cell dyscrasias such as multiple myeloma. The cell's profound dependence on the protein synthesis and degradation machinery represents a key vulnerability. The high expression of UPR components like [HERPUD1](/details-gene/9709) indicates that these cells operate near the threshold of proteotoxic collapse. This reliance on the ubiquitin-proteasome system, underscored by the specificity of [UBC](/details-gene/7316), is the biological basis for the efficacy of proteasome inhibitors, a cornerstone of multiple myeloma therapy. Furthermore, several of the top markers have established clinical relevance. For instance, serum levels of [B2M](/details-gene/567) are a critical prognostic factor in the staging of multiple myeloma, reflecting tumor burden and renal function. The intense metabolic activity, suggested by the specific expression of mitochondrial genes ([COX1](/details-gene/4512), [ND1](/details-gene/4535)), may also represent a therapeutic target, as malignancies often exhibit altered metabolic dependencies. ## Potential Mechanisms and Research Directions 1. **Hypothesis: The ER-resident protein folding and stress response machinery in plasma cells is not a generic housekeeping system but a highly specialized, co-regulated "secretome module" that is rate-limiting for effective humoral immunity and represents a point of failure in pathology.** * **Surprising Findings:** It is noteworthy that the most specific genetic marker for a [plasma cell](/details-cell/CL0000786) is not an immunoglobulin gene itself, but [HERPUD1](/details-gene/9709), an ER stress protein. This suggests that the primary challenge defining this cell type is managing the consequences of its massive protein output, a feature that may be more unique than the product itself. * **Testable Questions:** Does the targeted inhibition of plasma cell-specific chaperones, such as [MZB1](/details-gene/51237), selectively impair immunoglobulin folding and secretion, leading to apoptosis in malignant plasma cells? Could this offer a more targeted therapeutic approach for multiple myeloma compared to broad-acting proteasome inhibitors? 2. **Hypothesis: The specific gene signature of high mitochondrial oxidative phosphorylation distinguishes the metabolic state of long-lived plasma cells from other activated lymphocytes, and this dependence on aerobic respiration is crucial for their survival and function within the bone marrow niche.** * **Surprising Findings:** Many highly activated and proliferative immune cells adopt a Warburg-like glycolytic metabolism. The strong specificity signal for multiple mitochondrial electron transport chain genes ([COX1](/details-gene/4512), [COX2](/details-gene/4513), [CYTB](/details-gene/4519)) suggests that terminally differentiated plasma cells revert to, or specialize in, a state of high oxidative phosphorylation, which is more typically associated with quiescent or long-lived cells. * **Testable Questions:** How do variations in the bone marrow microenvironment, such as local oxygen tension and nutrient availability, impact the expression of these key mitochondrial genes? Does pharmacological inhibition of the electron transport chain disproportionately affect the viability and secretory capacity of plasma cells compared to their B-cell precursors?