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Plasma cell

A plasma cell is a terminally differentiated B lymphocyte, a type of white blood cell, that serves as the primary producer of antibodies in the humoral immune response, secreting thousands of immunoglobulin molecules per second to combat pathogens and maintain long-term immunity.^[1] These cells arise from activated B cells following antigenic stimulation, undergoing a maturation process driven by transcription factors such as Blimp-1, IRF4, and XBP-1, which reprogram the cell to prioritize antibody synthesis over proliferation.^[1] Morphologically, plasma cells are larger than typical lymphocytes (14–20 micrometers in diameter), featuring an eccentric nucleus with a characteristic "clock-face" chromatin pattern, abundant rough endoplasmic reticulum for protein production, and a prominent perinuclear Golgi apparatus, often marked by surface expression of CD38 and CD138.^[1] Beyond antibody secretion, plasma cells exhibit diverse functions, including the production of immunomodulatory cytokines like IL-10, IL-35, and IL-17, which regulate immune tolerance, inflammation, and even hematopoiesis in various tissues.^[2] Long-lived plasma cells, capable of persisting for decades in survival niches such as the bone marrow and gut mucosa, ensure sustained serological memory against infections and vaccines, with the majority residing in bone marrow niches supported by stromal cells, while others persist in mucosal tissues like the gut.^[2] Dysregulation of plasma cells contributes to immunodeficiencies (e.g., agammaglobulinemia from impaired differentiation) and pathologies like multiple myeloma or autoimmune diseases, where autoreactive plasma cells drive chronic antibody-mediated damage.^[1] Plasma cells were first described in 1875 by Wilhelm Waldeyer, with their role as the primary antibody-producing cells confirmed experimentally in the mid-20th century; they remain central to understanding adaptive immunity and therapeutic targeting in B cell disorders.^[1]^[3]^[4]

Structure

Morphology

Plasma cells are ovoid or round cells typically measuring 9 to 20 μm in diameter, with a mean of approximately 14 μm, making them larger than naive B cells which are around 7-10 μm.^[5] Under light microscopy, they exhibit a characteristic basophilic cytoplasm due to the abundance of rough endoplasmic reticulum (RER) involved in protein synthesis, an eccentric nucleus, and a perinuclear halo corresponding to the Golgi apparatus region.^[1] The nucleus is round or oval, positioned off-center, and features coarse heterochromatin arranged in a distinctive clock-face or cartwheel pattern, with clumps of chromatin distributed along the nuclear periphery.^[1] Electron microscopy reveals further ultrastructural details that underscore their specialization for antibody production. The cytoplasm is dominated by extensive arrays of RER, appearing as parallel stacks of flattened cisternae studded with ribosomes, often containing granular material within the lumen.^[6]^[1] A prominent Golgi apparatus occupies the perinuclear halo, consisting of vesicles, tubules, and dense globules for processing and packaging proteins.^[7] The nucleus shows a higher nucleo-cytoplasmic ratio in immature forms with well-developed nucleoli, while mature plasma cells have a denser, eccentric nucleus with less prominent nucleoli.^[7] Occasionally, cytoplasmic inclusions such as Russell bodies—dilated RER sacs filled with dense material—may be observed, reflecting accumulated immunoglobulins.^[7]

Surface antigens

Plasma cells are distinguished from other immune cells by a unique profile of surface antigens that reflect their terminal differentiation from B lymphocytes. The primary identifier is CD138 (also known as syndecan-1), a heparan sulfate proteoglycan highly expressed on the surface of mature plasma cells, which facilitates their adhesion to extracellular matrix components in survival niches.^[8] Co-expression of CD38, a multifunctional ectoenzyme, at high levels further characterizes plasma cells, enabling their robust detection in both normal and pathological contexts.^[9] In contrast, B cell-associated markers such as CD19 and CD20 are downregulated or absent; CD19 expression is low or negative on mature bone marrow plasma cells, while CD20 is typically not expressed, marking the loss of B cell identity.^[8]^[10] During differentiation from activated B cells, plasma cells undergo significant changes in surface antigen expression, including the loss of major histocompatibility complex class II (MHC II) molecules and the B cell receptor (BCR). MHC II, which is highly expressed on B cells for antigen presentation, is progressively downregulated as plasmablasts mature into long-lived plasma cells, correlating with their reduced role in T cell interactions.^[11] Similarly, surface BCR (membrane-bound immunoglobulin) is lost or markedly reduced, shifting the cell's focus from antigen recognition to antibody secretion; this is particularly evident in IgG-producing plasma cells, though some IgA- and IgM-secreting cells may retain low levels.^[10] These alterations begin in plasmablasts, which often retain partial B cell marker expression (e.g., CD19 positive, CD138 low), and culminate in mature plasma cells with a streamlined profile dominated by CD138 and CD38.^[12] Adhesion molecules like CD44, a hyaluronan receptor, are upregulated on plasma cells to support their homing to bone marrow niches, where interactions with stromal cells promote survival.^[13] This homing is critical for long-lived plasma cells, which express high CD44 levels to facilitate retention in supportive microenvironments. In diagnostics, these surface antigens are essential for identifying plasma cells via flow cytometry and immunohistochemistry. Flow cytometry panels typically gate on CD38^high CD138⁺ populations, with absence of CD19 and CD20 confirming maturity and distinguishing normal from neoplastic cells, such as in multiple myeloma where aberrant expression (e.g., CD19^- CD56⁺) aids in detecting minimal residual disease.^[8] Immunohistochemistry relies heavily on CD138 for visualizing plasma cells in tissue biopsies, offering high specificity for plasmacytic infiltrates.^[14] These markers' expression patterns also correlate with morphological features, such as the eccentric nucleus in CD138⁺ cells observed in bone marrow aspirates.^[8]

Development and Lifespan

Differentiation from B cells

Plasma cells differentiate from mature B cells through activation pathways that initiate the transition to antibody-secreting cells. In T cell-dependent activation, which occurs primarily in germinal centers of secondary lymphoid organs, naive B cells recognize antigens via their B cell receptor (BCR) and receive co-stimulatory signals from CD4+ helper T cells, leading to proliferation and differentiation into plasmablasts.^[15] T cell-independent activation, in contrast, involves direct stimulation of B cells by antigens with repetitive structures, such as polysaccharides, bypassing T cell help and resulting in more rapid but lower-affinity responses, often producing IgM-secreting plasmablasts.^[16] Key signals driving this differentiation include CD40 ligand (CD40L) expressed on activated T cells, which binds CD40 on B cells to promote survival and proliferation, synergizing with cytokines such as interleukin-4 (IL-4) and IL-21.^[17] IL-4 supports B cell growth and class switching to IgG and IgE, while IL-21 potently induces plasmablast formation and immunoglobulin secretion by upregulating terminal differentiation programs.^[18] Additionally, B cell-activating factor (BAFF, also known as BLyS) and a proliferation-inducing ligand (APRIL) provide survival signals through receptors like TACI and BCMA, enhancing the commitment to the plasma cell lineage.^[19] The transcriptional program for plasma cell differentiation is orchestrated by key factors, including interferon regulatory factor 4 (IRF4) and PRDM1 (encoding Blimp-1). IRF4 initiates the process by activating Prdm1 expression and repressing B cell identity genes, while Blimp-1 further enforces the plasmacytic state by silencing proliferation-associated genes like Bcl6 and promoting immunoglobulin secretion machinery.^[20] These factors act in a dose-dependent manner, with graded IRF4 levels coordinating transitions from activated B cells to plasmablasts.^[21] Plasmablasts emerge as the immediate precursors to plasma cells, characterized by initial secretion of immunoglobulins, predominantly IgM in early responses. In germinal centers during T cell-dependent responses, B cells undergo affinity maturation through somatic hypermutation, which introduces mutations in antibody variable regions to enhance antigen binding, followed by selection of high-affinity clones.^[22] Class-switch recombination also occurs here, diversifying antibody isotypes from IgM to IgG, IgA, or IgE under the influence of cytokines like IL-4 or IFN-γ, preparing plasmablasts for effector functions.^[23] This differentiation process unfolds rapidly following antigen exposure, with activated B cells proliferating and forming plasmablasts within 3–7 days in vivo, depending on the pathway and antigen type.^[24]

Immature and short-lived plasma cells

Immature and short-lived plasma cells arise as proliferating antibody-secreting cells primarily in extrafollicular regions of secondary lymphoid organs, such as the red pulp of the spleen and medullary cords of lymph nodes, where they expand rapidly in response to antigenic stimulation.^[25] These cells transition from plasmablasts, the immediate proliferating precursors derived from activated B cells under cytokine influences like IL-21, and are characterized by markers such as CD19 expression in humans and B220 in mice, reflecting their immature state.^[25] Their high proliferative capacity enables a swift buildup during the early phase of an immune response, generating large numbers—often in the millions within the spleen—to mount an immediate defense.^[26] These plasma cells exhibit a brief lifespan of approximately 3 to 5 days, constrained by limited access to survival signals in their transient niches within lymphoid tissues.^[27] Unlike more persistent counterparts, they lack robust support from stromal cells or cytokines, leading to rapid turnover and contributing to the resolution of acute responses.^[25] In terms of function, they predominantly secrete low-affinity IgM antibodies, providing essential but non-specialized humoral support to control early pathogen dissemination before affinity maturation occurs.^[26] Apoptosis in these cells is tightly regulated by the Bcl-2 family of proteins, where insufficient anti-apoptotic members like Bcl-2 result in heightened sensitivity to intrinsic death pathways triggered by bioenergetic stress or endoplasmic reticulum overload from high secretory demands.^[25] They also display vulnerability to Fas-mediated apoptosis in precursor stages, facilitating the elimination of excess cells post-initial response to prevent overproduction.^[28] Overall, while comprising the majority of antibody-secreting cells in the acute phase, most undergo programmed death shortly after, ensuring a controlled and temporary contribution to immunity.^[26]

Long-lived plasma cells and survival niches

Following differentiation in germinal centers, a subset of plasma cells acquires competence for homing to the bone marrow through upregulation of the chemokine receptor CXCR4, which interacts with its ligand SDF-1 (CXCL12) produced by bone marrow stromal cells, directing migration and retention in survival niches.^[29] This CXCR4/SDF-1 axis is essential for post-germinal center plasma cells to exit peripheral sites and establish residence in the bone marrow, where they compete for limited niche space.^[30] Within the bone marrow, long-lived plasma cells occupy specialized survival niches formed by interactions with stromal cells, including mesenchymal progenitors and perivascular reticular cells, which provide essential survival signals.^[30] Key factors in these niches include APRIL and BAFF, secreted by stromal cells and non-hematopoietic nurse-like cells, which bind to receptors such as BCMA and TACI on plasma cells to promote longevity through anti-apoptotic pathways.^[31] Additionally, IL-6 signaling from niche-associated cells enhances plasma cell persistence by supporting metabolic fitness and inhibiting cell death. These extrinsic cues enable a small population of plasma cells, comprising approximately 1% of total bone marrow cells, to maintain high antibody output despite their scarcity.^[32] Long-lived plasma cells enter a non-proliferative, quiescent state characterized by repression of the transcription factor Bach2, which facilitates terminal differentiation and suppresses proliferation genes, ensuring long-term survival without division.^[33] Elevated expression of CD44 on these cells further contributes to quiescence by mediating adhesion to extracellular matrix components in the niche, stabilizing their position and reducing motility.^[34] This quiescent phenotype allows plasma cells to persist for decades, as evidenced by sustained tetanus-specific immunity in humans for over 10 years post-vaccination, underpinning serological memory.^[35] Recent research highlights the role of hypoxia-inducible factors (HIFs), particularly HIF-1α, in maintaining these niches under the bone marrow's low-oxygen environment (PO₂ ~2-3%), where it upregulates stromal-derived factors like fibronectin to support plasma cell adhesion and survival.^[36] Metabolic adaptations driven by HIF signaling, including enhanced glycolysis and mitochondrial function, enable long-lived plasma cells to meet the energy demands of continuous antibody secretion while resisting oxidative stress, further promoting their longevity.^[36]

Function

Antibody secretion

Plasma cells are highly specialized for the high-rate secretion of antibodies, producing up to 10,000 immunoglobulin molecules per cell per second through an expanded rough endoplasmic reticulum (RER) and Golgi apparatus pathway.^[37] This secretory capacity arises from their morphological adaptations, including abundant RER, which supports the massive protein synthesis required for antibody production.^[37] The process begins with the translation of immunoglobulin heavy and light chains on polysomes associated with the RER membrane, followed by their translocation into the ER lumen for folding and assembly.^[38] Within the ER, heavy and light chains undergo proper folding, assisted by chaperones, and form disulfide bonds to assemble into complete immunoglobulin monomers or multimers, with N-linked glycosylation occurring to stabilize the structure and facilitate trafficking.^[38] Glycosylation patterns vary by isotype, influencing antibody function and stability during secretion.^[39] Plasma cells produce diverse isotypes—IgG, IgA, IgE, and IgM—determined by prior class-switch recombination in B cell precursors, allowing adaptation to different immune challenges.^[40] The transcription factor XBP1 plays a central role in expanding the secretory apparatus by upregulating genes for ER biogenesis, protein folding, and vesicular transport, enabling sustained high-output antibody production.^[41] To manage the resulting ER stress from this intense synthetic load, plasma cells activate a specialized unfolded protein response (UPR) that selectively engages the IRE1-XBP1 arm while suppressing the PERK branch, thereby promoting survival and secretion without triggering apoptosis.^[42] Secretion rates can be quantified ex vivo using enzyme-linked immunospot (ELISPOT) assays, which detect antibody spots formed by individual cells, revealing heterogeneity in output among plasma cell populations.^[43]

Role in humoral immunity

Plasma cells serve as the primary effectors of the humoral immune response by secreting antibodies that neutralize pathogens and facilitate opsonization, thereby marking infectious agents for phagocytosis by immune cells such as macrophages and neutrophils.^[44] These antibodies bind to specific epitopes on pathogens, preventing their attachment to host cells and inhibiting replication, while opsonization enhances the efficiency of pathogen clearance through Fc receptor-mediated uptake.^[45]^[46] In the context of immunological memory, long-lived plasma cells provide sustained humoral immunity by continuously producing antibodies long after the initial antigen encounter, operating independently of T cell support following their differentiation from B cells.^[47] This autonomy ensures persistent protection against reinfection without the need for ongoing antigenic stimulation or T cell activation.^[48] Different antibody isotypes produced by plasma cells contribute to site-specific defense mechanisms; for instance, IgG antibodies dominate systemic circulation, providing broad protection against blood-borne pathogens, whereas IgA antibodies are secreted at mucosal surfaces to reinforce barriers in the respiratory, gastrointestinal, and urogenital tracts.^[49]^[50] Once migrated to survival niches such as the bone marrow or mucosal tissues, plasma cells exhibit minimal direct interactions with other immune cells, instead delivering protection primarily through the release of soluble antibodies into the bloodstream or local secretions.^[51] Beyond antibody production, plasma cells can secrete immunomodulatory cytokines such as interleukin-10 (IL-10), IL-35, and IL-17, which contribute to regulatory functions in immunity. IL-10 and IL-35 from regulatory plasma cells promote immune tolerance and suppress excessive inflammation, while IL-17 production by certain plasma cell subsets may enhance responses against extracellular pathogens or contribute to autoimmune pathology.^[52]^[53] The functional role of plasma cells in humoral immunity is evolutionarily conserved across jawed vertebrates, where B cell-derived plasma cell-like effectors generate adaptive antibody responses to combat diverse pathogens.^[54] Quantitatively, these cells maintain lifelong serum antibody levels, as exemplified by measles-specific IgG titers with an estimated half-life exceeding 3,000 years, ensuring durable protection against reinfection.^[55]^[56]

Clinical Significance

Plasma cell neoplasms and disorders

Plasma cell neoplasms represent a group of disorders characterized by the uncontrolled proliferation of clonal plasma cells, leading to excessive production of monoclonal immunoglobulins or light chains. Multiple myeloma, the most common plasma cell neoplasm, involves the clonal expansion of malignant plasma cells in the bone marrow, often exceeding 10% of cellularity, which disrupts normal hematopoiesis and bone remodeling.^[57] This proliferation results in the classic CRAB symptoms: hypercalcemia due to osteolytic bone resorption, renal failure from light chain cast nephropathy or hypercalcemia, anemia from bone marrow infiltration and cytokine-mediated suppression, and bone lesions manifesting as lytic lesions, fractures, or osteoporosis.^[58] Related premalignant and malignant disorders include monoclonal gammopathy of undetermined significance (MGUS), Waldenström macroglobulinemia, and AL amyloidosis. MGUS is an asymptomatic precursor condition defined by a serum monoclonal protein less than 3 g/dL, bone marrow clonal plasma cells less than 10%, and absence of end-organ damage or myeloma-defining events.^[59] Waldenström macroglobulinemia features an IgM monoclonal protein produced by lymphoplasmacytic cells in the bone marrow, often causing hyperviscosity syndrome, anemia, and lymphadenopathy due to IgM-mediated effects.^[60] In AL amyloidosis, misfolded light chains secreted by clonal plasma cells deposit as amyloid fibrils in organs, particularly the heart and kidneys, leading to restrictive cardiomyopathy and nephrotic syndrome.^[61] Dysfunction or overactivity of plasma cells also contributes to autoimmune diseases through the persistent production of pathogenic autoantibodies. In systemic lupus erythematosus (SLE), autoreactive plasma cells secrete antibodies such as anti-double-stranded DNA and anti-Smith, driving immune complex deposition and tissue inflammation in organs like the kidneys and skin.^[62] Similarly, in rheumatoid arthritis, long-lived plasma cells in the synovium produce rheumatoid factor and anti-citrullinated protein antibodies, perpetuating chronic joint inflammation and erosion via autoantibody-mediated complement activation and immune cell recruitment.^[63] Plasma cell deficiencies underlie certain immunodeficiencies, resulting in impaired antibody production and recurrent infections. Common variable immunodeficiency (CVID) involves defective B-cell differentiation into plasma cells, leading to hypogammaglobulinemia, reduced switched memory B cells, and paucity of plasma cells in tissues, which predisposes to sinopulmonary infections and autoimmunity.^[64]^[65] Agammaglobulinemia, often X-linked, features an absence of mature B cells and thus plasma cells due to mutations in the BTK gene, causing profound hypogammaglobulinemia and susceptibility to bacterial infections from early infancy.^[66] Diagnosis of plasma cell neoplasms typically relies on laboratory and histopathological findings. Serum protein electrophoresis identifies monoclonal proteins (M-spikes) in over 80% of cases, while immunofixation confirms the immunoglobulin type; urine protein electrophoresis detects light chains (Bence Jones proteins).^[67] Bone marrow biopsy is essential, revealing clonal plasma cells often positive for CD138, with a threshold of 10% or greater (≥10%) clonal cells supporting a diagnosis of multiple myeloma when combined with myeloma-defining events.^[68]^[69] Post-2020 research has identified prolonged autoantibody production, such as antinuclear and antiphospholipid antibodies, in long COVID survivors, contributing to symptoms like fatigue and neurological dysfunction.^[70]^[71] This immune dysregulation may stem from SARS-CoV-2-induced B-cell hyperactivity, with new-onset autoantibodies persisting beyond 12 months in a subset of patients.^[72]

Therapeutic targeting and immunomodulation

Proteasome inhibitors, such as bortezomib, target the unfolded protein response (UPR) in plasma cells, which are highly sensitive due to their intense immunoglobulin synthesis and proteasomal workload.^[73] In multiple myeloma, bortezomib induces apoptosis by overwhelming the proteasome's capacity to degrade misfolded proteins accumulated during UPR activation.^[74] This mechanism has established bortezomib as a cornerstone therapy, improving response rates and survival in myeloma patients.^[75] Monoclonal antibodies like daratumumab target CD38, a surface antigen highly expressed on malignant plasma cells, inducing cell death through complement-dependent cytotoxicity, antibody-dependent cellular cytotoxicity, and phagocytosis.^[76] Approved for relapsed or refractory multiple myeloma, daratumumab monotherapy yields objective response rates of around 30% in heavily pretreated patients, with enhanced efficacy in combinations.^[77] Elotuzumab, targeting SLAMF7 (CD319), promotes natural killer cell-mediated antibody-dependent cellular cytotoxicity against myeloma cells while directly activating NK cells.^[78] Expressed uniformly on plasma cells, SLAMF7 enables elotuzumab to achieve progression-free survival benefits when combined with lenalidomide and dexamethasone in relapsed myeloma.^[79] Immunomodulatory drugs like lenalidomide enhance immune surveillance by activating T cells and natural killer cells, facilitating clearance of malignant plasma cells in multiple myeloma.^[80] Lenalidomide reduces programmed death-1 expression on T and NK cells, boosts interleukin-2 and interferon-γ secretion, and degrades the transcription factor Ikaros to promote cytotoxic responses.^[81] This leads to improved overall survival in combination regimens for both newly diagnosed and relapsed disease.^[82] Post-2020 emerging therapies include BCMA-targeted chimeric antigen receptor T-cell (CAR-T) therapy, such as idecabtagene vicleucel, approved in 2021 for relapsed or refractory multiple myeloma after at least four prior lines of therapy.^[83] Targeting B-cell maturation antigen (BCMA) on plasma cells, idecabtagene vicleucel achieves deep responses, with 73% overall response rates and 33% complete responses in pivotal trials.^[84] Bispecific antibodies, such as teclistamab (BCMA-CD3) and talquetamab (GPRC5D-CD3), redirect T cells to lyse malignant plasma cells, yielding response rates exceeding 60% in heavily pretreated patients. Recent 2025 data from real-world studies and combinations (e.g., teclistamab with talquetamab) confirm response rates exceeding 70-80% in relapsed/refractory cases.^[85]^[86] Inhibitors of APRIL and BAFF disrupt survival niches in the bone marrow by blocking these cytokines essential for long-lived plasma cell maintenance, leading to rapid depletion of plasma cells in preclinical models.^[87] In autoimmunity, B-cell depletion with rituximab indirectly reduces plasma cell precursors by targeting CD20-positive B cells, limiting replenishment of autoantibody-secreting plasma cells.^[88] This approach depletes short-lived autoreactive plasma cells in diseases like rheumatoid arthritis and systemic lupus erythematosus, though long-lived plasma cells persist.^[89] Plasma exchange removes circulating pathogenic antibodies produced by plasma cells, providing rapid symptom relief in antibody-mediated autoimmune conditions such as Guillain-Barré syndrome and myasthenia gravis.^[90] By filtering plasma and replacing it with albumin or donor plasma, this procedure reduces autoantibody levels by 50-70% per session.^[91] mRNA vaccines, such as those for SARS-CoV-2, boost the generation of long-lived plasma cells in the bone marrow to enhance humoral memory and sustained antibody production.^[92] These vaccines induce robust germinal center responses, leading to antigen-specific memory B cells that differentiate into long-lived plasma cells secreting neutralizing antibodies for months to years post-vaccination.^[93]

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Renal Manifestations of Plasma Cell Disorders
Waldenström macroglobulinemia is associated with an immunoglobulin M (IgM) monoclonal protein, and can cause hyperviscosity syndrome, anemia, lymphadenopathy, ...
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AL amyloidosis, Waldenström macroglobulinemia, and POEMS ...
AL amyloidosis typically develops from the background of a plasma cell neoplasm but can be associated with other lymphoproliferative disorders in which there ...
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Plasma Cell Differentiation Pathways in Systemic Lupus ...
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Autoantibodies represent a hallmark of rheumatoid arthritis (RA), with the rheumatoid factor (RF) and antibodies against citrullinated proteins (ACPA) being ...
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Common variable immunodeficiency is a disorder characterized by defective B cell function leading to impaired immunoglobulin production.
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Gastrointestinal Disorders Associated with Common Variable ...
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Agammaglobulinemia: X-linked (XLA) and autosomal recessive (ARA)
People with genetic causes of low or absent antibodies (agammaglobulinemia) have a severe form of antibody deficiency with absent B cells.
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Understanding and Interpreting Serum Protein Electrophoresis - AAFP
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Plasmablasts and plasma cells are sensitive to proteasome inhibitors such as bortezomib because of their high level of immunoglobulin synthesis, leading to ...
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Treatment of multiple myeloma with the immunostimulatory SLAMF7 ...
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Bispecific antibodies are a novel immunotherapeutic approach designed to bind antigens on malignant plasma cells and cytotoxic immune effector cells.
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Article CD138 and APRIL regulate plasma cell survival, competition ...
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Rituximab specifically depletes short-lived autoreactive plasma cells ...
B cell-depletion therapy through rituximab has already been shown to be effective in rheumatoid arthritis, multiple sclerosis, and several other autoimmune ...
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The role of plasma exchange in the management of autoimmune ...
The main mechanisms of action of TPE include the removal of circulating autoantibodies, immune complexes, complement components, cytokines and adhesion ...
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Plasma Exchange (Plasmapheresis)
Plasma exchange helps by removing these abnormal antibodies from the blood. Plasma exchange involves removing a person's blood drawn and putting their blood ...
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mRNA vaccines induce durable immune memory to SARS-CoV-2 ...
mRNA vaccines induce robust germinal center responses in humans (14, 15), which result in memory B cells that are specific for both the full-length SARS-CoV-2 ...
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SARS-CoV-2 specific plasma cells acquire long-lived phenotypes in ...
Basic mRNA vaccination with 3–4 doses are sufficient to induce memory plasma cells in man. Antigen-specific humoral immunity is based on an array of plasma ...