TNFRSF17 Human

What is TNFRSF17 and what are its key structural characteristics?

TNFRSF17, also known as B-cell maturation antigen (BCMA), is a type III membrane protein containing one extracellular cysteine-rich domain. The protein is encoded by the TNFRSF17 gene in humans and functions as a cell surface receptor within the tumor necrosis factor receptor superfamily . The mature protein is approximately 5.4 kDa in size, consisting of a single non-glycosylated polypeptide chain containing 50 amino acids with the sequence: AGQCSQNEYF DSLLHACIPC QLRCSSNTPP LTCQRYCNAS VTNSVKGTNA .

TNFRSF17 is primarily expressed on mature B-cells and various B-cell lines, where it recognizes and binds to B-cell activating factor (BAFF) . This receptor plays crucial roles in promoting B-cell survival, regulating humoral immunity, and activating important signaling pathways including NF-kappa-B and JNK .

What detection methods are most effective for studying TNFRSF17 expression in human tissues?

Several complementary approaches can be employed to detect TNFRSF17 expression:

• Flow Cytometry: This technique effectively identifies TNFRSF17 expression on cell surfaces. For example, studies have successfully detected TNFRSF17 in RPMI8226 human myeloma cell lines using monoclonal antibodies (such as MAB1931) followed by fluorophore-conjugated secondary antibodies . The protocol typically involves:

  • Cell preparation and fixation

  • Incubation with primary anti-TNFRSF17 antibody

  • Secondary antibody staining (e.g., Phycoerythrin-conjugated Anti-Mouse IgG)

  • Analysis using flow cytometry instruments

• Immunohistochemistry (IHC): This method allows visualization of TNFRSF17 in tissue sections. Protocols using immersion-fixed paraffin-embedded sections have successfully detected TNFRSF17 in human tonsil tissue . The procedure involves:

  • Heat-induced epitope retrieval using basic antigen retrieval reagents

  • Primary antibody incubation (5 μg/mL) at room temperature for 1 hour

  • Detection using HRP Polymer Antibody systems

  • DAB staining and hematoxylin counterstaining

• Recombinant Protein Technologies: Tagged versions of TNFRSF17 (His-tagged, Fc-tagged, or fluorescently labeled) can be utilized as standards or for functional studies .

What experimental models best recapitulate TNFRSF17 function in human disease?

Recent advancements have introduced genetically engineered mouse models that better reflect human multiple myeloma (MM) pathophysiology in which TNFRSF17 plays an important role:

• Genetically Engineered Mouse Models: Researchers have developed fifteen models of human-like MM incorporating key pathogenic elements . These models:

  • Carry transgenes for MM genetic drivers including NF-κB signaling activation

  • Demonstrate transcriptional profiles similar to human MM based on RNA-seq analysis

  • Enable observation of disease progression from MGUS (monoclonal gammopathy of undetermined significance) to full MM

  • Allow for preclinical testing of immunotherapy strategies

• Cell Line Models: RPMI8226 human myeloma cell line is frequently used as an in vitro model for studying TNFRSF17 expression and function . These cells express TNFRSF17 on their surface and can be used for:

  • Flow cytometry analysis

  • Functional assays

  • Drug screening

  • Signaling pathway investigations

• Transcriptomic Models: RNA-seq approaches comparing normal plasma cells with MGUS and MM cells have identified signature transcriptional profiles that include TNFRSF17 expression patterns . Principal component analysis (PCA) and gene-set enrichment analysis (GSEA) demonstrate shared transcriptional trajectories between mouse models and human disease, validating their use for TNFRSF17 studies.

How can CRISPR/Cas9 techniques be optimized for TNFRSF17 gene editing?

CRISPR/Cas9 gene editing of TNFRSF17 requires careful design and implementation:

• Guide RNA Selection: The Feng Zhang laboratory at the Broad Institute has designed specific guide RNA sequences that uniquely target the TNFRSF17 gene with minimal off-target effects . When implementing CRISPR editing of TNFRSF17:

  • At least two gRNA constructs per gene are recommended for increased success probability

  • Sequences should be checked against target gene sequences, especially when targeting specific splice variants or exons

  • Complete gRNA expression systems including U6 promoter, spacer sequence, gRNA scaffold, and terminator are necessary

• Vector Selection Considerations: When working with TNFRSF17 CRISPR systems:

  • Vectors with appropriate selection markers should be chosen based on the experimental design

  • Sequence verification is essential before proceeding with gene editing experiments

  • Creating genomically edited cell lines requires optimization of transfection, selection, and validation protocols

• Recent Developments: Publications from 2024 report high-specificity CRISPR-mediated genome engineering in anti-BCMA allogeneic CAR T cells that suppresses allograft rejection in preclinical models , demonstrating the evolving applications of this technology.

What is the role of TNFRSF17 in plasma cell differentiation and multiple myeloma pathogenesis?

TNFRSF17 plays critical roles in normal and malignant plasma cell biology:

• Normal Plasma Cell Function: TNFRSF17 signaling is essential for the survival and function of plasma cells . It:

  • Promotes B-cell survival through activation of pro-survival signaling pathways

  • Contributes to humoral immunity regulation

  • Participates in plasma cell differentiation from B-cells

• Multiple Myeloma Pathogenesis: TNFRSF17 is implicated in MM development and progression:

  • It has been identified as a significant component in plasma cell-associated transcriptional signatures

  • When combined with CD38, it serves as a valuable marker for identifying malignant plasma cells

  • Transcriptome profiling across various conditions and cell types has helped establish TNFRSF17 as a prioritized gene within plasma cell-associated module M12.15 from the BloodGen3 repertoire

• Therapeutic Targeting: Novel immunotherapy strategies targeting TNFRSF17 include:

  • Monoclonal antibodies

  • T cell engagers

  • Chimeric antigen receptor (CAR) T cell therapies

  • Preclinical evaluation of CD8+ anti-BCMA mRNA CAR T cells has shown promise for MM treatment

How do TNFRSF17 signaling pathways contribute to B-cell survival and potential therapeutic targeting?

TNFRSF17 activates several signaling cascades crucial for B-cell function:

• Ligand Interactions: TNFRSF17 binds to multiple TNF family ligands:

  • TNFSF13B/BLyS/BAFF

  • TNFSF13/APRIL

  • These interactions trigger downstream signaling events

• Signaling Pathways: Upon ligand binding, TNFRSF17 activates:

  • NF-kappa-B pathway, crucial for cell survival and inflammatory responses

  • JNK pathway, involved in stress responses and apoptosis regulation

  • These pathways collectively promote B-cell survival and function

• Therapeutic Implications: Understanding these pathways has led to multiple therapeutic approaches:

  • Targeting the receptor directly with antibodies or immunoconjugates

  • Disrupting ligand-receptor interactions

  • Interfering with downstream signaling components

  • Development of BCMA-targeted CAR T-cell therapies that have shown remarkable efficacy in clinical trials for multiple myeloma

What are the cutting-edge techniques for quantifying TNFRSF17 expression and signaling activities?

Several advanced methodologies can be employed for comprehensive TNFRSF17 analysis:

• Fluorescently-Labeled Recombinant Proteins: Recombinant human TNFRSF17 proteins with specific tags (His, Fc, Avi) and fluorescent labels (R-PE, AF488) enable sophisticated detection approaches . For example:

  • R-Phycoerythrin labeled TNFRSF17 can be used for immunostaining and protein tracing

  • NH2-Reactive R-Phycoerythrin forms covalent bonds with amino groups without requiring activation processes

  • These reagents remain stable for at least 12 months when stored properly (-20 to -80°C)

• Integrated AI-Human Approaches: Recent methodologies combine Large Language Models (LLMs) with human expertise to identify and prioritize TNFRSF17 and related genes within transcriptional modules :

  • High-throughput screening using LLMs to score and rank genes based on predefined criteria

  • High-resolution scoring and fact-checking with human expert validation

  • Integration of transcriptome profiling data to assess expression levels across various conditions

• CyTOF (Mass Cytometry): This technique combines flow cytometry with mass spectrometry for high-dimensional analysis:

  • CyTOF-ready antibodies against TNFRSF17 are now available

  • Enables simultaneous detection of TNFRSF17 alongside numerous other markers

  • Provides deeper insights into cellular phenotypes and signaling states

How can researchers validate TNFRSF17-targeted therapeutic approaches in preclinical models?

Validation strategies for TNFRSF17-targeted therapies require robust preclinical assessment:

• Mouse Model Selection: Genetically engineered mouse models that reflect human MM pathogenesis are essential:

  • Models with NF-κB signaling activation and KRAS alterations can recapitulate key aspects of human disease

  • RNA-seq comparison between mouse and human samples confirms similar transcriptional trajectories

  • These models allow observation of disease progression stages, from MGUS to MM

• Functional Validation: Multiple approaches confirm therapeutic efficacy:

  • Flow cytometry to verify target engagement

  • Immunohistochemistry to assess tissue distribution and target accessibility

  • Monitoring of downstream signaling pathway activation/inhibition

  • Assessment of cell survival and proliferation markers

• Therapeutic Assessment: Recent publications highlight successful approaches:

  • Anti-BCMA CAR T cells have shown efficacy in preclinical myeloma models

  • CRISPR-modified allogeneic CAR T cells targeting BCMA have demonstrated reduced allograft rejection

  • Combination strategies targeting multiple myeloma-associated pathways alongside TNFRSF17 have shown enhanced efficacy

What are the most promising approaches for overcoming resistance to TNFRSF17-targeted therapies?

Several strategies are being investigated to address therapy resistance:

• Combinatorial Targeting: Targeting TNFRSF17 alongside other plasma cell markers:

  • CD38 has been identified as a complementary target to TNFRSF17 through integrated AI-human approaches

  • IGJ represents another promising alternative marker that correlates with plasma cell function

  • Dual-targeting approaches may prevent escape through antigen downregulation

• Novel Engineering Approaches: Advanced protein and cellular engineering:

  • Development of multi-specific antibodies targeting TNFRSF17 and additional antigens

  • Engineering of CAR T cells with enhanced persistence and tumor-penetrating capabilities

  • Modification of binding domains to improve affinity and specificity

• Microenvironment Modulation: Addressing tumor microenvironment factors:

  • Combining TNFRSF17-targeted therapies with immune checkpoint inhibitors

  • Targeting stromal support mechanisms that promote therapy resistance

  • Modulating bone marrow niche factors that contribute to malignant plasma cell survival

How do genetic variations in TNFRSF17 impact therapeutic response and disease progression?

Understanding genetic alterations is critical for personalizing TNFRSF17-targeted approaches:

• Expression Level Variations: Differences in TNFRSF17 expression:

  • Transcriptome profiling has revealed variable expression across different disease states

  • Expression correlates with module averages in the plasma cell-associated transcriptional signatures

  • Higher expression levels may predict better responses to targeted therapies

• Genetic Alterations: Mutations and structural variations:

  • Gene editing studies using CRISPR/Cas9 have helped characterize the impact of specific alterations

  • Correlation between genetic alterations and disease progression requires further investigation

  • The impact of genetic variants on binding of therapeutic antibodies remains an important area of study

• Clonal Evolution: Changes during disease progression:

  • Monitoring TNFRSF17 expression throughout disease evolution from MGUS to MM provides insights into therapeutic windows

  • Clonal selection under therapeutic pressure may lead to emergence of TNFRSF17-negative subclones

  • Sequential sampling and analysis may help predict and prevent resistance development