Tpsab1 Antibody

What is the TPSAB1 gene and what protein does it encode?

TPSAB1 (tryptase alpha/beta 1) encodes a serine protease that is predominantly expressed in mast cells. The protein is synthesized as a pre-proenzyme and processed to a mature form that is stored in mast cell granules and released upon mast cell activation. The gene has been mapped to chromosome 16p13.3, and its official NCBI Gene ID is 7177 . The TPSAB1 protein consists of 275 amino acids with a calculated molecular weight of approximately 31 kDa, though the observed molecular weight in experimental conditions typically ranges from 32-38 kDa due to post-translational modifications . Functionally, TPSAB1 is involved in immune responses and inflammatory processes, particularly those mediated by mast cells.

What applications are TPSAB1 antibodies validated for?

TPSAB1 antibodies have been validated for multiple experimental applications in immunological and molecular biology research. Based on comprehensive testing, these antibodies can be reliably used in:

• Western Blot (WB): Detecting TPSAB1 protein in cell and tissue lysates with recommended dilutions of 1:500-1:2000

• Immunohistochemistry (IHC): Visualizing TPSAB1 expression in tissue sections with dilutions ranging from 1:50-1:500

• Immunofluorescence (IF): Both on paraformaldehyde-fixed tissues (IF-P) and cell cultures (IF/ICC) at dilutions of 1:50-1:500

• Flow Cytometry (FC): For intracellular staining at 0.20 μg per 10^6 cells in a 100 μl suspension

• Immunoprecipitation (IP): Using 0.5-4.0 μg for 1.0-3.0 mg of total protein lysate

• ELISA: For quantitative detection of TPSAB1 protein

Selection of the appropriate application should be based on your specific research question and sample type. For optimal results, validation in your specific experimental system is recommended.

Which tissue and cell types show positive TPSAB1 expression?

TPSAB1 expression has been documented in several tissue and cell types through antibody-based detection methods. Specifically:

Additionally, research has shown that TPSAB1 is predominantly expressed in mast cells, which are found throughout connective tissues, particularly near blood vessels, nerves, and mucosal surfaces. The protein is especially abundant in the gastrointestinal tract, respiratory system, and skin—regions where mast cells play crucial roles in immune surveillance and inflammation .

What are the optimal antigen retrieval conditions for TPSAB1 IHC staining?

For optimal immunohistochemical detection of TPSAB1 in formalin-fixed, paraffin-embedded tissues, specific antigen retrieval conditions have been determined through extensive testing. The recommended protocol includes:

Primary recommendation: Heat-induced epitope retrieval (HIER) using TE buffer at pH 9.0 . This alkaline condition has been shown to effectively unmask TPSAB1 epitopes while preserving tissue morphology.

Alternative method: If suboptimal results are obtained with TE buffer, citrate buffer at pH 6.0 can be used as an alternative . The acidic environment provided by citrate buffer offers a different mechanism for breaking protein cross-links formed during fixation.

Procedure optimization steps:

• Section tissue at 4-5 μm thickness

• Mount on positively charged slides

• Deparaffinize and rehydrate following standard protocols

• Perform antigen retrieval using your chosen buffer

• Allow slides to cool to room temperature before proceeding with blocking and antibody incubation

• Optimize incubation times and temperatures based on your specific tissue type

The selection between these two antigen retrieval methods should be determined empirically for each tissue type and experimental system to achieve optimal signal-to-noise ratio.

How should I optimize antibody concentration for Western blot detection of TPSAB1?

Optimizing antibody concentration for Western blot detection of TPSAB1 requires a systematic approach to achieve specific signal with minimal background. Based on validated protocols:

• Initial concentration range: Begin with the manufacturer's recommended dilution range of 1:500-1:2000

• Titration approach:

  • Prepare a dilution series (e.g., 1:500, 1:1000, 1:2000) of the primary antibody

  • Use consistent protein loading (20-50 μg of total protein) across all lanes

  • Include positive controls (e.g., A431 cells, K-562 cells) and negative controls (cell lines known not to express TPSAB1)

• Assessment criteria:

  • Signal intensity at the expected molecular weight (32-38 kDa)

  • Signal-to-noise ratio (minimize background staining)

  • Specificity (absence of non-specific bands)

• Fine-tuning considerations:

  • If signal is too strong with excessive background, increase dilution

  • If signal is weak but specific, decrease dilution

  • Adjust blocking conditions (5% non-fat dry milk vs. BSA)

  • Optimize secondary antibody concentration and incubation time

  • Consider longer exposure times for weaker signals

• Protocol optimization:

  • Incubation temperature (4°C overnight vs. room temperature for 1-2 hours)

  • Washing stringency (increasing detergent concentration or wash duration for high background)

Remember that the observed molecular weight for TPSAB1 typically ranges from 32-38 kDa , which may vary slightly depending on post-translational modifications and the specific isoform detected.

What are the key considerations for immunofluorescence staining of TPSAB1 in tissue sections?

Successful immunofluorescence staining of TPSAB1 in tissue sections requires attention to several critical factors:

• Fixation and processing:

  • For frozen sections: 4% paraformaldehyde fixation for 10-15 minutes is optimal

  • For paraffin sections: Proper antigen retrieval is essential (TE buffer pH 9.0 preferred)

• Antibody selection and validation:

  • Confirm the antibody is validated for immunofluorescence applications

  • Use antibodies with demonstrated reactivity in your species of interest (human, mouse, rat)

  • Consider the specific epitope recognized by the antibody (e.g., AA 151-275)

• Protocol optimization:

  • Antibody dilution: Start with recommended range (1:50-1:500 for IF-P)

  • Incubation time: 1-2 hours at room temperature or overnight at 4°C

  • Blocking solution: 5-10% serum from the same species as the secondary antibody plus 0.1-0.3% Triton X-100

• Controls and validation:

  • Positive control: Include mouse skin tissue sections (known to express TPSAB1)

  • Negative control: Primary antibody omission

  • Autofluorescence assessment: Examine unstained section under all channels

• Signal amplification considerations:

  • For weak signals, consider tyramide signal amplification

  • Use conjugated primary antibodies (e.g., DyLight 488-conjugated anti-TPSAB1) for direct detection

  • Balance signal amplification with potential background increase

• Counterstaining strategy:

  • DAPI for nuclear visualization

  • Consider additional cell-type specific markers to confirm mast cell identity

  • Avoid fluorophores with spectral overlap to prevent bleed-through

Optimal results are typically achieved with dilutions between 1:50-1:500 , though this should be determined empirically for each experimental system.

How can I use TPSAB1 antibodies to study hereditary alpha-tryptasemia (HαT)?

Hereditary alpha-tryptasemia (HαT) is a genetic condition characterized by elevated basal serum tryptase levels due to increased copy numbers of the TPSAB1 gene . Investigating this condition using TPSAB1 antibodies requires several sophisticated approaches:

• Copy number analysis integration:

  • Combine droplet digital PCR for TPSAB1 gene copy number assessment with antibody-based protein detection

  • Compare tryptase protein levels (using TPSAB1 antibodies) with gene copy number to establish genotype-phenotype correlations

• Tissue and cellular distribution studies:

  • Use immunohistochemistry (IHC) with TPSAB1 antibodies to map tissue distribution of tryptase in HαT patients versus controls

  • Compare mast cell numbers and tryptase content in tissues such as skin, intestine, and respiratory mucosa

  • Recommended antibody dilutions for IHC: 1:50-1:500

• Functional assessment of mast cells:

  • Flow cytometry with TPSAB1 antibodies can be used to assess intracellular tryptase levels in isolated mast cells

  • Combine with surface markers (CD203c, HLA-DR, FcεRI) to characterize the mast cell phenotype in HαT

• B cell interaction studies:

  • As research has identified increased memory B cells in HαT patients , co-staining experiments using TPSAB1 antibodies (mast cells) and B cell markers can examine spatial relationships

  • Investigate potential mast cell-B cell cross-talk mechanisms

• Gastrointestinal pathology investigation:

  • Since HαT is associated with GI symptoms, TPSAB1 antibodies can be used to examine small intestinal mast cell distribution and activation state

  • Research has shown expansion of intestinal mast cells with expression of CD203c, HLA-DR, and FcεRI in HαT patients

• Methodology notes:

  • For flow cytometry: Use 0.20 μg anti-TPSAB1 per 10^6 cells in 100 μl suspension

  • For tissue IHC: Optimal antigen retrieval with TE buffer pH 9.0

  • For co-immunoprecipitation studies: 0.5-4.0 μg antibody for 1.0-3.0 mg protein lysate

Research has demonstrated that HαT patients (approximately 5% of irritable bowel syndrome cohorts) show distinct immunological features including increased intestinal epithelial cell pyroptosis and elevated GI-associated antibodies , making TPSAB1 antibodies valuable tools for investigating this condition.

What are the critical factors for multiplexed immunofluorescence using TPSAB1 antibodies?

Multiplexed immunofluorescence incorporating TPSAB1 antibodies enables simultaneous visualization of tryptase-positive mast cells alongside other cell types or markers. Several critical factors must be considered for successful implementation:

• Antibody compatibility assessment:

  • Host species considerations: Avoid primary antibodies raised in the same species unless using directly conjugated antibodies

  • When combining rabbit polyclonal anti-TPSAB1 with other antibodies, ensure sequential staining or use species-specific secondary antibodies

  • For co-labeling, consider using mouse monoclonal TPSAB1 antibodies (clones C16, C10, 2A10-B5) with rabbit antibodies against other targets

• Epitope blocking strategy:

  • When using multiple primary antibodies, implement complete blocking between sequential staining steps

  • Consider tyramide signal amplification for sequential multiplexing, which allows antibody stripping while preserving covalently-bound fluorophores

• Fluorophore selection criteria:

  • Choose fluorophores with minimal spectral overlap

  • When available, use directly conjugated antibodies such as TPSAB1/1963 with DyLight 488

  • Balance brightness with potential photobleaching during multispectral imaging

• Panel design considerations:

  • For mast cell subset characterization: Combine TPSAB1 with CD117, FcεRI, and chymase

  • For tissue microenvironment studies: Include markers for adjacent cell types (e.g., CD3 for T cells, CD20 for B cells)

  • For HαT studies: Include CD203c, HLA-DR, and FcεRI based on known expression patterns

• Image acquisition optimization:

  • Employ sequential scanning to minimize bleed-through

  • Use appropriate exposure settings for each channel

  • Consider spectral unmixing for highly multiplexed panels

• Validation approach:

  • Perform single-color controls alongside multiplexed samples

  • Include fluorescence-minus-one (FMO) controls

  • Validate staining patterns with alternative methods (e.g., single-color IHC)

A well-designed multiplexed panel might include TPSAB1 (diluted 1:50-1:500) alongside markers for mast cell activation status, tissue-specific cell types, and microenvironmental features to provide comprehensive spatial context for mast cell distribution and activation states.

How can I analyze contradictory results when using different TPSAB1 antibody clones?

When facing contradictory results with different TPSAB1 antibody clones, a systematic troubleshooting approach is essential:

• Epitope mapping comparison:

  • Analyze the specific epitopes recognized by each antibody clone:

    • Some antibodies target AA 151-275

    • Others target more restricted regions like AA 161-262 or AA 115-233

  • Epitope accessibility may differ between applications (native vs. denatured conditions)

  • Post-translational modifications might affect epitope recognition

• Isoform specificity assessment:

  • TPSAB1 can exist in multiple isoforms (alpha and beta variants)

  • Determine whether each antibody specifically recognizes alpha tryptase, beta tryptase, or both

  • Review manufacturer documentation for isoform specificity

• Validation strategy:

  • Sibling antibody comparison: Test multiple antibodies targeting different epitopes

  • Orthogonal validation: Confirm results with non-antibody methods (e.g., mRNA expression)

  • Genetic models: Use samples with known TPSAB1 gene copy numbers as controls

• Application-specific optimization:

  • Western blot: Optimize denaturing conditions for each antibody

  • IHC/IF: Compare different antigen retrieval methods (TE buffer pH 9.0 vs. citrate buffer pH 6.0)

  • Flow cytometry: Adjust fixation and permeabilization protocols

• Technical resolution approach:

  • For monoclonal antibodies: Consider epitope masking issues

  • For polyclonal antibodies: Evaluate batch-to-batch variation

  • Test antibody performance in samples with known high expression (e.g., human tonsillitis tissue)

• Documentation and reporting:

  • Maintain detailed records of antibody clone, lot number, and protocol

  • In publications, specify the exact antibody clone, epitope, and validation methods

  • Consider depositing validation data in public repositories

When analyzing contradictory results, remember that the observed molecular weight for TPSAB1 typically ranges from 32-38 kDa , and expression patterns should align with known biology (high expression in mast cell-rich tissues).

What strategies can improve signal-to-noise ratio when using TPSAB1 antibodies for IHC?

Optimizing signal-to-noise ratio for TPSAB1 immunohistochemistry requires attention to multiple technical aspects:

• Antigen retrieval optimization:

  • Primary recommendation: TE buffer pH 9.0

  • Alternative approach: Citrate buffer pH 6.0

  • Optimize heating time and temperature (95-100°C for 15-30 minutes)

  • Allow gradual cooling to room temperature to prevent tissue detachment

• Blocking protocol enhancement:

  • Use 5-10% serum from the same species as the secondary antibody

  • Add 0.1-0.3% Triton X-100 for improved penetration

  • Consider dual blocking with both serum and protein-based blockers

  • Implement avidin/biotin blocking for biotin-based detection systems

• Antibody dilution and incubation refinement:

  • Test a titration series within the recommended range (1:50-1:500)

  • Extend primary antibody incubation (overnight at 4°C rather than 1 hour at room temperature)

  • Use antibody diluent containing stabilizing proteins and mild detergents

  • Consider signal amplification systems for weak signals

• Washing stringency adjustment:

  • Increase number of washes (5-6 washes of 5 minutes each)

  • Use TBST (TBS + 0.1% Tween-20) rather than PBS for more stringent washing

  • Ensure complete washing between each step

• Detection system selection:

  • For chromogenic detection: Consider polymer-based systems over avidin-biotin methods

  • For fluorescence: Use directly conjugated secondary antibodies or tyramide signal amplification

  • Adjust detection reagent incubation times based on signal intensity

• Control implementation:

  • Positive tissue control: Human tonsillitis or appendix tissue (known TPSAB1 expression)

  • Negative control: Primary antibody omission

  • Isotype control: Matched isotype antibody at same concentration

• Background reduction techniques:

  • Pre-absorb antibodies with tissue powder if non-specific binding persists

  • Use commercial background reducers for problematic tissues

  • Implement endogenous enzyme blocking (peroxidase/phosphatase)

  • Treat tissues with avidin/biotin blocking solutions if using biotin-based detection

By systematically optimizing these parameters, researchers can achieve clean, specific staining of TPSAB1 in tissue sections with minimal background interference.

How can I verify the specificity of my TPSAB1 antibody in Western blot applications?

Verifying TPSAB1 antibody specificity for Western blot requires a multi-faceted validation approach:

• Molecular weight confirmation:

  • The calculated molecular weight of TPSAB1 is 31 kDa (275 amino acids)

  • The experimentally observed molecular weight typically ranges from 32-38 kDa

  • Confirm that your detected band falls within this range

• Positive control inclusion:

  • Use cell lines with known TPSAB1 expression: A431 cells, K-562 cells

  • Include tissue samples with established expression: mouse liver tissue, rat liver tissue

  • Compare band intensity across samples with expected expression levels

• Negative control implementation:

  • Include cell lines known not to express TPSAB1

  • Use knockdown or knockout samples if available

  • Perform primary antibody omission controls

• Peptide competition assay:

  • Pre-incubate antibody with blocking peptide (if available)

  • A specific signal should be significantly reduced or eliminated

  • Non-specific bands will typically remain unchanged

• siRNA validation:

  • Compare samples from cells treated with TPSAB1-specific siRNA versus scrambled control

  • A specific signal should show reduced intensity in knockdown samples

  • Quantify knockdown efficiency by densitometry

• Loading control correlation:

  • Plot the relationship between loading amount and TPSAB1 signal intensity

  • A specific signal should show linear correlation with protein loading

  • Non-specific signals often don't show proportional relationship with loading

• Multiple antibody verification:

  • Test two or more antibodies targeting different TPSAB1 epitopes:

    • Antibodies to AA 151-275

    • Antibodies to AA 161-262

    • Antibodies to AA 115-233

  • Consistent detection at the same molecular weight supports specificity

• Protocol optimization:

  • Adjust antibody concentration within recommended range (1:500-1:2000)

  • Optimize blocking conditions (5% non-fat milk vs. BSA)

  • Increase washing stringency for high background

Using this comprehensive validation approach ensures that the signal detected in Western blot applications genuinely represents TPSAB1 protein rather than non-specific binding or cross-reactivity.

What protocols can be used to quantify TPSAB1 expression levels in tissues and cells?

Accurate quantification of TPSAB1 expression requires selection of appropriate methods based on research needs:

• Western blot densitometry:

  • Sample preparation: Use RIPA buffer with protease inhibitors

  • Protein loading: 20-50 μg total protein per lane

  • Antibody dilution: 1:500-1:2000

  • Analysis: Normalize band intensity to loading controls (β-actin, GAPDH)

  • Advantages: Provides relative quantification of protein levels

  • Limitations: Semi-quantitative, may miss cell-specific expression patterns

• Flow cytometry quantification:

  • Cell preparation: Fix with 4% paraformaldehyde, permeabilize with 0.1% saponin

  • Antibody concentration: 0.20 μg per 10^6 cells in 100 μl suspension

  • Analysis: Mean fluorescence intensity (MFI) relative to isotype control

  • Advantages: Single-cell resolution, high throughput

  • Ideal for: Isolated primary mast cells, cell lines (e.g., U-937 cells)

• Quantitative immunohistochemistry:

  • Tissue processing: FFPE sections with standardized antigen retrieval

  • Antibody dilution: 1:50-1:500

  • Analysis methods:

    • Positive cell counting (cells/mm²)

    • H-score calculation (staining intensity × percentage positive cells)

    • Digital image analysis with color deconvolution

  • Advantages: Preserves tissue architecture, allows spatial analysis

  • Best for: Human tonsillitis tissue, appendix tissue

• Sandwich ELISA:

  • Capture antibody: Anti-TPSAB1 (clone-dependent)

  • Detection antibody: Biotin-conjugated anti-TPSAB1 targeting different epitope

  • Standard curve: Recombinant TPSAB1 protein

  • Analysis: Absolute concentration (ng/ml or pg/ml)

  • Advantages: Highly quantitative, suitable for serum/plasma samples

  • Applications: Monitoring tryptase levels in HαT patients

• Multiplexed assay systems:

  • Method: Mesoscale Discovery or Luminex platforms

  • Advantage: Simultaneous quantification of multiple proteins

  • Application: Correlating TPSAB1 with other inflammatory mediators

• Mass spectrometry:

  • Sample preparation: Immunoprecipitation using 0.5-4.0 μg antibody for 1.0-3.0 mg protein

  • Analysis: Targeted proteomics with heavy-labeled peptide standards

  • Advantages: Absolute quantification, isoform discrimination

  • Best for: Distinguishing alpha vs. beta tryptase isoforms

The choice of quantification method should be guided by specific research questions, available sample types, and required level of quantitative precision. For clinical research on conditions like hereditary alpha-tryptasemia, combining multiple approaches provides the most comprehensive assessment of TPSAB1 expression.

How can TPSAB1 antibodies help investigate mast cell involvement in inflammatory intestinal disorders?

TPSAB1 antibodies serve as valuable tools for investigating mast cell contributions to inflammatory intestinal disorders through several methodological approaches:

• Quantitative mast cell assessment:

  • Immunohistochemistry using anti-TPSAB1 (1:50-1:500 dilution) to quantify mast cell numbers in intestinal biopsies

  • Compare mast cell density across different intestinal segments and disease states

  • Correlate with clinical symptoms and disease severity

• Mast cell phenotyping:

  • Multiplexed immunofluorescence combining TPSAB1 with CD203c, HLA-DR, and FcεRI

  • Research has shown that mast cells in hereditary alpha-tryptasemia express these activation markers

  • Compare phenotypic profiles between irritable bowel syndrome, inflammatory bowel disease, and healthy controls

• Barrier function assessment:

  • Co-staining for TPSAB1 and epithelial junction proteins

  • Correlate mast cell proximity to areas of epithelial damage

  • Investigate mechanisms of increased intestinal epithelial cell pyroptosis observed in HαT patients

• B cell interaction analysis:

  • Research has identified increased total and class-switched memory B cells in hereditary alpha-tryptasemia

  • Use dual immunofluorescence with TPSAB1 and B cell markers to map spatial relationships

  • Investigate potential mast cell regulation of intestinal B cell responses

• Methodological approach:

  • Tissue preparation: Formalin-fixed, paraffin-embedded intestinal biopsies

  • Antigen retrieval: TE buffer pH 9.0 (primary recommendation) or citrate buffer pH 6.0 (alternative)

  • Antibody validation: Human appendix tissue serves as positive control

  • Quantification: Digital image analysis of whole slide scans

• Clinical correlation:

  • Integrate TPSAB1 staining results with serum tryptase measurements

  • Stratify patients by TPSAB1 gene copy number

  • Compare autoantibody profiles between patient subgroups

Recent research has shown that approximately 5% of irritable bowel syndrome patients have hereditary alpha-tryptasemia with increased TPSAB1 copies . These patients exhibit distinct immunological characteristics including increased GI-associated antibodies that differentiate them from both healthy controls and Crohn's disease patients , making TPSAB1 antibodies essential tools for stratifying patient populations and investigating underlying disease mechanisms.

What techniques are used to correlate TPSAB1 expression with mast cell activation in experimental models?

Correlating TPSAB1 expression with mast cell activation status in experimental models requires integrated methodological approaches:

• In vivo activation assessment:

  • Baseline measurement: Immunohistochemistry for TPSAB1 (1:50-1:500) in tissue sections

  • Post-activation analysis: Sequential sections stained for TPSAB1 and degranulation markers

  • Quantification: Mast cell counting, degranulation index calculation, and correlation analysis

• Ex vivo tissue explant models:

  • Tissue preparation: Fresh tissue maintained in culture medium

  • Activation protocol: IgE/antigen exposure or calcium ionophore treatment

  • Analysis: Dual immunofluorescence for TPSAB1 and activation markers

  • Measurement: Tryptase release into culture supernatant by ELISA

• Isolated primary mast cell experiments:

  • Cell source: Bone marrow-derived or tissue-isolated mast cells

  • Activation protocols: IgE crosslinking, substance P, or compound 48/80

  • Flow cytometry approach: Intracellular TPSAB1 (0.20 μg per 10^6 cells) plus surface CD63/CD107a

  • Correlation: Compare intracellular TPSAB1 content with degranulation markers

• Real-time activation monitoring:

  • Live cell imaging with fluorescent TPSAB1 antibodies (e.g., DyLight 488-conjugated)

  • Time-lapse recording of mast cell degranulation

  • Quantification of granule exocytosis kinetics

  • Correlation with functional outcomes (e.g., cytokine release)

• Genetic manipulation approaches:

  • TPSAB1 knockdown/knockout validation by Western blot (1:500-1:2000)

  • Rescue experiments with exogenous tryptase

  • Phenotypic characterization of mast cell function

• Multi-parameter analysis:

  • Combine tryptase measurements with other activation markers:

    • Histamine release

    • β-hexosaminidase activity

    • Cytokine/chemokine production

  • Calculate correlation coefficients between parameters

  • Develop integrated activation index incorporating multiple markers

• Disease model applications:

  • Allergic inflammation models: Compare TPSAB1 levels pre- and post-challenge

  • Intestinal inflammation: Correlate with epithelial permeability changes

  • Neurogenic inflammation: Assess mast cell-nerve interactions

By implementing these techniques, researchers can establish meaningful correlations between TPSAB1 expression patterns and functional mast cell activation states across various experimental models, providing insights into both physiological and pathological roles of mast cell tryptase.