FSCN1 Antibody

What is FSCN1 and what cellular functions does it regulate?

FSCN1 is a 55 kDa actin-bundling protein containing two major actin binding sites that facilitate cytoskeletal organization. Its activity is regulated through phosphorylation mechanisms which modulate its actin-binding capabilities . FSCN1 plays critical roles in cell migration, adhesion, and the formation of cell projections such as filopodia. Recent research has identified its potential involvement in inflammatory processes including pyroptosis, particularly in vascular diseases like atherosclerosis .

What is the cellular and tissue distribution pattern of FSCN1?

FSCN1 exhibits a specific expression pattern with high expression in dendritic cells and endothelial cells. Single-cell RNA sequencing data from atherosclerotic tissues has confirmed that FSCN1 is primarily expressed in endothelial cells in this pathological context . Importantly, FSCN1 is uniformly negative in lymphoid cells, plasma cells, and myeloid cells under normal conditions, which contributes to its utility as a differential diagnostic marker .

What are the common research applications for FSCN1 antibodies?

FSCN1 antibodies are employed across multiple research methodologies including:

• Western Blot (WB): For detecting the 55 kDa FSCN1 protein

• Immunohistochemistry (IHC): Particularly valuable for diagnostic pathology

• Immunofluorescence (IF): For visualization of subcellular localization

• Flow Cytometry: For quantitative cellular analysis

Over 110 citations in the scientific literature reference the use of FSCN1 antibodies across these applications . When selecting an antibody, researchers should consider the specific application requirements and validate antibody performance in their experimental system.

What types of FSCN1 antibodies are available for research?

FSCN1 antibodies are available in multiple formats including:

CF® dye conjugates offer exceptional brightness and photostability, though blue fluorescent conjugates (CF®405S, CF®405M) are not recommended for low-abundance targets due to higher background and lower fluorescence .

How can FSCN1 antibodies be utilized in differentiating lymphoma subtypes?

FSCN1 antibodies serve as valuable diagnostic tools in hematopathology, particularly for distinguishing Hodgkin lymphoma from non-Hodgkin lymphoma in challenging cases. The antibody demonstrates high sensitivity for Reed-Sternberg cells and variants in nodular sclerosis, mixed cellularity, and lymphocyte depletion Hodgkin's disease .

Methodological approach:

• Use paraffin-embedded tissue sections (5μm thickness)

• Perform heat-induced epitope retrieval

• Apply optimized FSCN1 antibody dilution (typically 1:100)

• Include appropriate positive (dendritic cells) and negative (lymphocytes) controls

• Evaluate cytoplasmic staining patterns with particular attention to Reed-Sternberg cells

The absence of FSCN1 expression in neoplastic follicles of follicular lymphoma can help distinguish this condition from reactive follicular hyperplasia, which exhibits normal or increased follicular dendritic cells .

What is the significance of FSCN1 in atherosclerosis pathogenesis?

Recent transcriptomic analysis has identified FSCN1 as a potential therapeutic target for atherosclerosis. Cross-sectional clinical studies have demonstrated that elevated FSCN1 levels are associated with increased risk of atherosclerosis .

Key research findings include:

• FSCN1 is upregulated in human atherosclerotic samples compared to normal tissues

• Higher expression is observed in advanced atherosclerotic plaques versus early plaques

• FSCN1 is primarily expressed in endothelial cells in atherosclerotic contexts

• Knockdown of FSCN1 reduces pyroptosis and increases migration in mouse aortic endothelial cells (MAECs)

These findings suggest that FSCN1 modulation could potentially alleviate atherosclerosis development and progression, positioning it as both a prognostic biomarker and therapeutic target.

What experimental approaches are recommended for studying FSCN1 function in endothelial cells?

Based on recent atherosclerosis research, the following experimental approaches are recommended:

• In vitro models:

  • Oxidized low-density lipoprotein (ox-LDL) treatment of mouse aortic endothelial cells (MAECs) to induce FSCN1 expression

  • FSCN1 knockdown using lentiviral shRNA vectors

  • Assessment of pyroptosis markers (NLRP3, caspase-1, GSDMD, IL-1β, IL-18)

  • Cell migration assays (wound healing, transwell) to evaluate functional effects

• In vivo models:

  • Apoe knockout mice fed with high-fat diet (HFD)

  • Tissue-specific FSCN1 knockdown approaches

  • Immunohistochemical analysis of aortic tissues

  • Single-cell RNA sequencing to evaluate cell-specific expression patterns

How can researchers validate the protein-protein interactions of FSCN1?

Understanding FSCN1's molecular interactions is crucial for elucidating its function. Bioinformatic analysis using tools like STRING has identified potential FSCN1-interacting proteins including AKT1, RAB35, and FLNA . To experimentally validate these interactions, researchers should consider:

• Co-immunoprecipitation (Co-IP) with FSCN1 antibodies followed by mass spectrometry

• Proximity ligation assays (PLA) to visualize protein interactions in situ

• FRET/BRET approaches for real-time interaction monitoring

• GST pull-down assays with recombinant proteins

• Yeast two-hybrid screening for novel interaction partners

These approaches can help establish the FSCN1 interactome and provide insights into its regulatory mechanisms.

What methods are effective for studying FSCN1's role in pyroptosis?

Recent research has implicated FSCN1 in pyroptosis regulation, particularly in endothelial cells during atherosclerosis development . To investigate this connection, researchers should:

• Measure canonical pyroptosis markers:

  • NLRP3 inflammasome activation

  • Caspase-1 cleavage

  • GSDMD cleavage

  • IL-1β and IL-18 release

• Utilize FSCN1 knockdown and overexpression models:

  • Lentiviral delivery of shRNA for knockdown

  • Plasmid transfection for overexpression

  • CRISPR/Cas9 for genetic knockout

• Implement appropriate pyroptosis assays:

  • LDH release assay to measure cell death

  • Propidium iodide uptake to visualize membrane pore formation

  • ASC speck formation assay

  • Caspase-1 activity assays

Understanding FSCN1's role in pyroptosis could reveal novel therapeutic approaches for inflammatory diseases like atherosclerosis .

How does Epstein-Barr virus (EBV) infection affect FSCN1 expression?

Evidence suggests that FSCN1 expression may be induced by Epstein-Barr virus (EBV) infection of B cells . For researchers investigating this relationship, consider:

• Utilize EBV infection models in appropriate B cell lines

• Monitor FSCN1 expression kinetics post-infection using:

  • Western blot

  • qRT-PCR

  • Immunofluorescence

• Investigate specific EBV latent or lytic genes responsible for FSCN1 induction

• Determine if EBV-positive vs. EBV-negative lymphomas differ in FSCN1 expression patterns

This relationship has important implications for understanding virus-associated malignancies and may explain FSCN1 expression in certain EBV-positive pathologies.

What are the optimal protocols for detecting FSCN1 in tissue samples?

For immunohistochemical detection of FSCN1 in formalin-fixed paraffin-embedded tissues:

• Sample preparation:

  • 5μm tissue sections on positively charged slides

  • Deparaffinization and rehydration

• Antigen retrieval:

  • Heat-induced epitope retrieval (HIER) using citrate buffer (pH 6.0)

  • Pressure cooker treatment (20 minutes)

• Antibody application:

  • Primary antibody: Anti-FSCN1 (1:100 dilution)

  • Incubation: Overnight at 4°C or 1 hour at room temperature

  • Detection system: HRP-polymer based with DAB chromogen

• Evaluation methodology:

  • Scoring system based on staining intensity (0-3) multiplied by percentage of positive cells (1-4)

  • High expression: score >5; Low expression: score ≤5

How can researchers ensure specificity of FSCN1 antibodies in their experimental systems?

To validate FSCN1 antibody specificity:

• Positive and negative controls:

  • Use cell lines with known FSCN1 expression levels (e.g., CAL-27 and SCC-25 cell lines show high expression)

  • Include tissues with established FSCN1 expression patterns (dendritic cells positive; lymphocytes negative)

• Knockdown validation:

  • Utilize FSCN1 knockdown models via shRNA or siRNA

  • Confirm reduced signal by Western blot and immunostaining

• Multiple antibody approach:

  • Compare results using antibodies from different sources or clones

  • Verify consistent staining patterns across antibodies

• Peptide competition:

  • Pre-incubate antibody with immunizing peptide

  • Confirm signal reduction/elimination

What experimental design is recommended for studying FSCN1 in atherosclerosis models?

Based on successful research approaches, the following experimental design is recommended:

• Clinical component:

  • Cross-sectional study measuring circulating FSCN1 levels via ELISA

  • Statistical analysis using logistic regression and ROC curves

  • Association analysis with atherosclerosis risk factors

• Animal models:

  • Apoe knockout mice fed with high-fat diet

  • Tissue collection for histological and molecular analysis

  • Immunohistochemistry for FSCN1 expression in aortic tissues

• Cellular models:

  • ox-LDL treatment of mouse aortic endothelial cells (MAECs)

  • FSCN1 knockdown via lentiviral vectors

  • Assessment of:

    • Pyroptosis markers (NLRP3, caspase-1, GSDMD)

    • Cell migration capacity

    • Cytokine production (IL-1β, IL-18)

This multi-level approach provides comprehensive insight into FSCN1's role in atherosclerosis pathogenesis.

How might FSCN1 serve as a therapeutic target for atherosclerosis?

FSCN1's potential as a therapeutic target for atherosclerosis is supported by several research findings:

• Expression pattern:

  • Upregulated in human atherosclerotic samples

  • Higher expression in advanced versus early atherosclerotic plaques

  • Primarily expressed in endothelial cells

• Functional effects:

  • FSCN1 knockdown reduces pyroptosis in endothelial cells

  • FSCN1 knockdown increases endothelial cell migration

  • These effects may promote plaque stability and endothelial repair

• Potential therapeutic approaches:

  • Small molecule inhibitors targeting FSCN1

  • RNA interference strategies (siRNA, shRNA)

  • Monoclonal antibodies against FSCN1

• Biomarker potential:

  • ROC curve analysis has demonstrated FSCN1's potential as a diagnostic marker

  • Circulating FSCN1 levels correlate with atherosclerosis risk

What are the challenges in interpreting contradictory FSCN1 functional data across different cell types?

Researchers should consider the following when encountering contradictory FSCN1 functional data:

• Cell-type specificity:

  • FSCN1 has distinct functions in different cell types (endothelial cells vs. cancer cells)

  • Expression levels vary significantly between tissues

• Context-dependent effects:

  • FSCN1 promotes migration in some cancer cells but inhibits migration in endothelial cells

  • These contradictory effects may relate to different interacting partners

• Methodological considerations:

  • Different knockdown efficiencies may yield varying results

  • Experimental conditions (2D vs. 3D culture, matrix composition)

  • Timing of assessments after FSCN1 modulation

• Reconciliation strategies:

  • Perform comprehensive interactome analysis in each cell type

  • Consider phosphorylation status of FSCN1 across experimental systems

  • Evaluate downstream signaling pathway activation

Understanding these context-dependent functions is crucial for developing targeted therapeutic approaches.