TP53 (Ab-37) Antibody

What is the epitope specificity of TP53 (Ab-37) Antibody?

TP53 (Ab-37) Antibody recognizes the peptide sequence surrounding amino acids 35-39 (L-P-S-Q-A) derived from human p53 . This region is located in the amino-terminal end of p53, which contains a strong transcription activation signal . The antibody is designed to detect either native, unphosphorylated p53 at this position, or specifically the phosphorylated form at Serine 37, depending on which specific variant of the antibody is used.

How does TP53 (Ab-37) Antibody differ from other p53 antibodies?

Unlike antibodies targeting the DNA-binding domain (DBD) of p53 (such as PAb246, PAb1620) or the carboxyl-terminal regions (like PAb421), TP53 (Ab-37) targets the amino-terminal region . This distinction is significant because:

• The amino-terminal region contains key phosphorylation sites involved in p53 regulation

• Most p53 mutations occur in the central DNA-binding domain (codons 119-287), not in the N-terminal region

• The amino-terminal antibodies typically recognize denatured forms in immunoblots, while some antibodies to the folded domains only detect native protein

How should I validate the specificity of TP53 (Ab-37) Antibody in my experimental system?

To validate antibody specificity for TP53 (Ab-37), implement the following methodological approach:

• Use positive and negative controls:

  • Positive: Cell lines with high p53 expression (e.g., transformed cell lines)

  • Negative: TP53 knockout cell lines

• Peptide competition assay: Pre-incubate the antibody with the immunizing peptide (L-P-S-Q-A) before application to your samples. Signal should be reduced or eliminated if the antibody is specific .

• Molecular weight verification: Confirm that detected bands correspond to expected p53 molecular weight (~53 kDa) and any known isoforms .

• Phosphatase treatment: For phospho-specific variants, treat samples with phosphatase to confirm that the signal depends on phosphorylation status .

• Cross-validation: Compare results with a different p53 antibody recognizing a different epitope .

What considerations should be made when using TP53 (Ab-37) Antibody for detecting mutant forms of p53?

Most TP53 mutations (~66%) occur within the DNA-binding domains (Loop-L2, Loop-L3, and LSH motif) , rather than in the N-terminal region recognized by TP53 (Ab-37) Antibody. Therefore:

• TP53 (Ab-37) will likely detect both wild-type and most mutant p53 proteins, as the epitope region is generally preserved in most mutant forms.

• For mutation-specific detection, consider using antibodies specifically designed for mutation detection, such as those targeting R175H mutation or conformation-specific antibodies like PAb240 that recognize mutant forms .

• The distribution pattern of TP53 mutations in the DNA-binding motifs (based on research findings):

Data derived from study results presented in search result .

How can TP53 (Ab-37) Antibody be used to study p53 phosphorylation pathways in response to DNA damage?

Phosphorylation at Ser37 is a key post-translational modification of p53 in response to DNA damage. Using phospho-specific TP53 (Ab-37) antibody allows for temporal monitoring of this modification:

• Kinetics studies: Monitor the time course of Ser37 phosphorylation following DNA damage induction with agents like UV, ionizing radiation, or genotoxic drugs.

• Kinase inhibitor screens: Combine with inhibitors of ATM, ATR, DNA-PK, or other stress-responsive kinases to determine which pathway regulates Ser37 phosphorylation in your experimental model.

• Correlation with other modifications: Use in conjunction with antibodies against other phosphorylation sites (e.g., Ser15, Ser20, Ser392) to establish the sequence and interdependence of modification events .

• Functional outcomes: Correlate Ser37 phosphorylation with p53 transcriptional activity, protein-protein interactions, or cellular outcomes (cell cycle arrest, apoptosis).

Methodological note: When combining multiple phospho-specific antibodies, sequential immunoprecipitation approaches can reveal the proportion of p53 molecules with multiple modifications.

What is the significance of TP53 (Ab-37) in relation to p53's tumor suppressor function?

Serine 37 phosphorylation has significant implications for p53's tumor suppressor functions:

• Transcriptional activation: Phosphorylation at Ser37 alters p53's ability to bind DNA and activate transcription of target genes involved in cell cycle arrest and apoptosis .

• Protein stabilization: N-terminal phosphorylation events, including at Ser37, contribute to p53 stabilization by disrupting binding with MDM2, which normally targets p53 for degradation.

• Clinical correlations: Studies have shown that TP53 alterations correlate with poor clinical outcomes:

Data derived from meta-analysis presented in search result .

What are the optimal sample preparation methods for detecting p53 phosphorylation at Ser37?

For optimal detection of p53 phosphorylation at Ser37:

• Rapid sample collection and processing:

  • Harvest cells quickly to prevent phosphatase activity

  • Include phosphatase inhibitors (sodium fluoride, sodium orthovanadate, β-glycerophosphate) in all buffers

• Lysis buffer composition:

  • RIPA or NP-40 buffer supplemented with protease inhibitors

  • Include phosphatase inhibitors at appropriate concentrations

  • Maintain cold temperature throughout processing

• Protein enrichment strategies:

  • Consider immunoprecipitation to concentrate p53 before Western blotting

  • For low-abundance phosphorylated forms, increase protein loading (50-100 μg per lane)

• Preservation of phospho-epitopes:

  • For fixed samples (IF/IHC), use paraformaldehyde fixation rather than methanol

  • Avoid repeated freeze-thaw cycles of protein lysates

• Storage conditions:

  • Store antibody in small aliquots at -20°C to avoid freeze-thaw cycles

  • For long-term storage of samples, maintain at -80°C with protease and phosphatase inhibitors

How can TP53 (Ab-37) Antibody be used in conjunction with other methods to comprehensively characterize p53 status?

A comprehensive p53 characterization strategy should combine antibody-based detection with complementary techniques:

• Genomic analysis:

  • Sequencing of TP53 gene to identify mutations

  • Comparison of sequencing data with antibody detection to correlate genotype and phenotype

• Transcriptomic profiling:

  • RT-PCR or RNA-seq to assess p53 transcript levels and isoforms

  • Analysis of p53 target gene expression as functional readout

• Protein analysis workflow:

  • Western blot with multiple domain-specific antibodies (N-terminal, DNA-binding domain, C-terminal)

  • Immunoprecipitation to study p53 protein complexes

  • Mass spectrometry to identify post-translational modifications and interacting partners

• Functional assays:

  • Reporter assays to measure p53 transcriptional activity

  • Cell cycle analysis to assess functional outcomes of p53 activation

  • Apoptosis assays to determine cell fate decisions

This integrated approach provides comprehensive insights into p53 status, transcriptional activity, and functional consequences in your experimental system.

What are common pitfalls when using TP53 (Ab-37) Antibody and how can they be addressed?

How can contradictory results between TP53 (Ab-37) Antibody detection and other p53 assessment methods be reconciled?

When facing contradictory results between antibody detection and other methods, consider these analytical approaches:

• Mutation type vs. epitope location:

  • Nonsense or frameshift mutations may eliminate the epitope completely

  • Missense mutations outside the epitope region may preserve antibody binding despite altered function

• Protein stabilization phenomena:

  • Some mutations increase p53 stability, leading to higher protein levels despite reduced function

  • Phosphorylation at Ser37 may occur on functionally inactive p53 mutants

• Analytical considerations:

  • Different methodologies have different sensitivity thresholds

  • IHC scoring systems vary between studies, complicating direct comparisons

• Interpretation framework:

  • Combine data from multiple antibodies targeting different domains

  • Correlate with functional readouts (target gene expression, cell cycle arrest)

  • Consider the relationship between phosphorylation status and mutation context

Research has shown that while anti-p53 antibodies have high specificity, they lack sensitivity for TP53 mutation status . For conclusive results, complement antibody detection with sequencing or functional assays.

How is TP53 (Ab-37) Antibody being used in novel therapeutic approaches targeting p53?

Recent research has explored innovative therapeutic approaches involving p53 antibodies:

• Bispecific antibody development:

  • Research has shown that antibodies highly specific to common TP53 mutations (like R175H) can be converted into immunotherapeutic agents

  • These bispecific antibodies can redirect T cells to recognize cancer cells presenting p53 neoantigens

• Monitoring therapeutic response:

  • TP53 (Ab-37) can monitor phosphorylation status during treatment with drugs targeting p53 pathways

  • Changes in Ser37 phosphorylation may serve as pharmacodynamic biomarkers

• Combination therapy approaches:

  • Evaluating p53 status and activation can inform combination strategies with conventional chemotherapy, radiation, or targeted agents

• Emerging applications in molecular imaging:

  • Antibodies against mutant p53 have shown promise for cancer diagnostics using molecular imaging techniques

  • This approach could be valuable for patient stratification and monitoring treatment response

What are the latest advancements in quantitative assessment of p53 using TP53 (Ab-37) Antibody?

Recent technological advances have enhanced quantitative p53 assessment:

• Quartz crystal microbalance (QCM) systems:

  • Allow direct gravimetric measurement of antibody-antigen binding

  • Provide independent measures of surface-immobilized protein concentration

  • Enable comparison with fluorescence-based measurements

• Digital immunoassay platforms:

  • Single-molecule detection methods enhance sensitivity

  • Allow quantification of p53 at physiological concentrations

• Multiplexed detection systems:

  • Simultaneous quantification of multiple phosphorylation sites

  • Assessment of p53 modification patterns rather than single sites

• Automated image analysis for IHC/IF:

  • Machine learning algorithms for unbiased quantification

  • Reduction in inter-observer variability