SOX10 Antibody

What is SOX10 and what cell types express this protein?

SOX10 is a nuclear transcription factor in the SOX (SRY-related HMG-Box) family of proteins that plays a crucial role in neural crest development, peripheral nervous system development, and functions as a nucleocytoplasmic shuttle protein . SOX10 expression is detected in multiple cell types:

• Neural crest-derived cells: melanocytes and Schwann cells

• Central nervous system glial cells and mature oligodendrocytes

• Breast myoepithelial and lobular epithelial cells

• Salivary gland myoepithelial cells

• Eccrine cells in skin

In pathological tissues, SOX10 is expressed in:

• 92.6% of melanomas (238/257), including 98% of desmoplastic and spindle cell variants

• 100% of nevi (20/20) and schwannomas (28/28)

• 16.5% of invasive ductal breast carcinomas (18/109)

• 53.7% of astrocytomas (22/41)

• 4.0% of various sarcomas (4/99)

What are the optimal protocols for SOX10 immunohistochemistry in formalin-fixed, paraffin-embedded tissues?

For optimal SOX10 immunohistochemical detection in FFPE tissues:

• Tissue preparation: Use properly fixed (formalin) and processed paraffin-embedded tissue sections .

• Antigen retrieval: Low pH antigen retrieval is recommended for many SOX10 antibodies . For the BC34 clone:

  • Heat-induced epitope retrieval using basic antigen retrieval reagent has been validated .

• Detection system:

  • Polymer detection systems with diaminobenzidine (DAB) visualization provide optimal results .

  • For fluorescence detection, appropriate secondary antibodies such as NorthernLights™ 557-conjugated Anti-Goat IgG can be used .

• Antibody concentration:

  • For monoclonal BC34: Use prediluted antibody as optimized by manufacturer .

  • For AF2864 polyclonal: 10-15 μg/mL for 1-3 hours at room temperature has been validated .

• Counterstaining:

  • Hematoxylin counterstaining provides optimal nuclear contrast .

  • For fluorescence applications, DAPI counterstaining for nuclear visualization .

• Controls:

  • Positive control: Melanoma tissue or cell lines such as SK-Mel-28 .

  • Negative control: Known SOX10-negative tissue processed identically to patient samples .

  • Nonspecific negative reagent control: IgG1 isotype control should be included .

How can I validate SOX10 antibody specificity for my experimental applications?

Validating SOX10 antibody specificity requires a multi-approach strategy:

• Molecular weight verification: Confirm the detected band corresponds to SOX10's predicted molecular weight (49 kDa) using Western blot .

• Recombinant protein control: Test antibody against purified SOX10 recombinant protein .

• Positive and negative cell lines:

  • Positive controls: SK-Mel-28 (human melanoma), A-375 (human melanoma), or BG01V human embryonic stem cells differentiated to neural crest .

  • Negative controls: Cell lines known to be SOX10-negative, such as HEK293T/17 .

• Genetic manipulation validation:

  • SOX10 knockdown using siRNA should reduce antibody signal .

  • SOX10 overexpression should increase antibody signal .

• Cross-reactivity assessment: Test antibody on protein arrays against multiple human proteins to determine Z-score (signal strength) and S-score (target specificity) . An S-score of at least 2.5 indicates specificity to the intended target.

• Immunoprecipitation validation: Perform IP using SOX10 antibody followed by mass spectrometry or Western blot to confirm specificity .

How does SOX10 expression correlation with immune cell infiltration in melanomas?

SOX10 expression in melanoma appears to have significant relationships with immune infiltration:

• Negative correlation with immune infiltrates:

  • In patient databases of cutaneous melanoma, SOX10 expression negatively correlates with immune infiltrates and immune-related pathways .

  • This suggests SOX10 may play a role in immune evasion.

• T-cell dependent tumor suppression:

  • In mouse models, SOX10 ablation decreases tumor growth in immune-competent models in a T-cell-dependent manner .

  • SOX10 knockout effects on tumor growth are more pronounced in immune-competent mice compared to immune-deficient mice, suggesting immune system involvement .

  • CD8+ T cells partially mediate the effects of SOX10 on tumor growth, though other immune cell types likely contribute .

• Experimental approaches to study this relationship:

  • Compare tumor growth in SOX10 wild-type versus SOX10-knockout cells in both immune-competent and immune-deficient mouse models .

  • Perform CD8+ T cell depletion experiments to determine T cell contribution .

  • Analyze immune cell infiltration in tumors using immunohistochemistry with SOX10 antibodies together with immune cell markers.

What is the relationship between SOX10 and immune checkpoint molecules?

SOX10 regulates multiple immune checkpoint molecules, potentially contributing to melanoma immune evasion:

• HVEM and CEACAM1 regulation:

  • SOX10 regulates expression of herpesvirus entry mediator (HVEM) and carcinoembryonic-antigen cell-adhesion molecule 1 (CEACAM1) .

  • These checkpoint proteins can influence T cell, NK cell, and B cell responses .

• PD-L1 regulation:

  • SOX10 overexpression increases PD-L1 expression in melanoma cells .

  • SOX10 knockdown using siRNA decreases PD-L1 expression .

  • SOX10 overexpression decreased melanoma cell susceptibility to NY-ESO-1-specific TCR-T cells, suggesting functional immune suppression .

• Experimental approaches:

  • Flow cytometry and Western blotting can be used to assess PD-L1 expression after SOX10 manipulation .

  • IFNγ ELISPOT assays can measure T cell response to SOX10-manipulated melanoma cells .

  • SOX10 antibodies can be used in co-immunoprecipitation experiments to investigate protein-protein interactions between SOX10 and immune signaling components.

How can SOX10 phosphorylation be detected and what is its significance?

SOX10 phosphorylation appears to be an important regulatory mechanism:

• Detection methods:

  • Immunoprecipitation using SOX10 antibodies followed by mass spectrometry analysis can identify phosphorylation sites .

  • Use of magnetic beads with SOX10 antibodies for pulldown, followed by elution with 50 mM glycine (pH 2.2) .

  • Western blot analysis of immunoprecipitated samples can detect phosphorylated forms of SOX10 .

• Functional significance:

  • Phosphorylation may regulate SOX10 protein stability and function in melanoma cells .

  • Cycloheximide pulse-chase experiments with wild-type versus phospho-mutant SOX10 constructs can assess effects on protein stability .

• Experimental approach:

  • Create phospho-mutant SOX10 constructs by site-directed mutagenesis of identified phosphorylation sites.

  • Compare the stability and transcriptional activity of wild-type versus phospho-mutant SOX10.

  • Use SOX10 antibodies for detection in these comparative studies.

What explains SOX10 expression heterogeneity in melanomas and what are its implications?

SOX10 exhibits significant heterogeneity in melanoma:

• Observed heterogeneity patterns:

  • Both intertumoral and intratumoral heterogeneity of SOX10 expression occurs in melanomas .

  • In a study of 14 tumors, 2 were homogeneously negative for SOX10, while 12 showed co-existence of SOX10-expressing and SOX10-deficient cells within the same tumor .

  • In a tumor microarray of 62 melanoma samples, 4 were completely SOX10-negative, while the remaining samples showed high intertumoral and intratumoral heterogeneity .

• Relationship to treatment:

  • SOX10 heterogeneity appears independent of treatment status, occurring in both treatment-naïve and treatment-resistant tumors .

  • No detectable difference in SOX10 expression was observed after BRAF inhibitor treatment in paired biopsies .

• Functional implications:

  • SOX10 loss is sufficient to induce an invasive slow-cycling state and tolerance to BRAF/MEK inhibitors .

  • SOX10-deficient cells represent a vulnerable subpopulation that may be targeted through upregulation of cellular inhibitors of apoptosis-2 (cIAP2) .

• Experimental approaches:

  • Single-cell RNA sequencing to characterize heterogeneity .

  • Immunohistochemistry with SOX10 antibodies to visualize spatial heterogeneity .

  • Development of strategies to target SOX10-deficient subpopulations.

How can SOX10 antibodies be used to study protein-protein interactions?

SOX10 antibodies are valuable tools for investigating protein-protein interactions:

• Co-immunoprecipitation approaches:

  • SOX10 antibodies can be used to pull down SOX10 and its interacting partners, followed by Western blot analysis for potential binding partners .

  • A Co-IP study confirmed interaction between SOX10 and β-catenin by overexpressing tagged proteins and analyzing immunoprecipitates .

• Experimental design:

  • Express tagged versions of SOX10 (e.g., HA-tagged) and potential interacting partners (e.g., flag-tagged β-catenin) in cells .

  • Immunoprecipitate with anti-tag antibodies or directly with SOX10 antibodies.

  • Analyze precipitates by Western blotting for co-precipitated proteins.

  • Validate interactions by testing different expression ratios and competition assays .

• Functional validation:

  • Transcriptional reporter assays can be used to assess functional consequences of protein interactions .

  • Luciferase reporter constructs containing SOX10-responsive elements can measure transcriptional activity .

What role does SOX10 play in cardiac regeneration and how can it be studied?

Recent research has revealed unexpected roles for SOX10 in cardiac tissue:

• SOX10 in cardiac regeneration:

  • SOX10+ cardiomyocytes contribute to myocardial regeneration .

  • Genetic ablation of SOX10+ cardiomyocytes impairs cardiac regeneration, indicating these cells play a role in heart repair .

• Experimental approaches:

  • SOX10 reporter lines (e.g., sox10:GFP) can be used to track SOX10-expressing cells in heart tissue .

  • SOX10 antibodies can be used for immunohistochemical detection in cardiac tissue.

  • Lineage tracing experiments can determine the fate of SOX10+ cells during cardiac regeneration.

• Research considerations:

  • Inconsistencies between SOX10 mRNA detection and reporter expression have been observed, possibly due to partial silencing of the reporter or transient SOX10 expression in progenitor cells .

  • Both SOX10 antibody staining and genetic reporter approaches should be used to comprehensively track SOX10+ cells.

How can researchers address conflicting SOX10 antibody results in their experiments?

When facing conflicting SOX10 antibody results:

• Possible sources of discrepancy:

  • Antibody specificity issues (different antibodies may recognize different epitopes) .

  • Technical variations in staining protocols, including antigen retrieval methods .

  • Heterogeneous SOX10 expression in samples, especially in melanomas .

  • Post-translational modifications affecting epitope recognition .

• Methodological approaches to resolve conflicts:

  • Use multiple SOX10 antibodies targeting different epitopes.

  • Compare monoclonal versus polyclonal antibodies.

  • Validate with orthogonal techniques (mRNA detection, reporter constructs).

  • Include positive and negative controls in each experiment .

  • Test different antigen retrieval methods and fixation protocols.

• Quantification approaches:

  • For heterogeneous expression, quantify percentage of positive cells rather than binary positive/negative categorization .

  • Use H-score calculation which accounts for both staining intensity and percentage of positive cells .

  • Digital image analysis may provide more objective quantification than visual scoring.

What is the significance of SOX10 in triple-negative breast cancer diagnosis?

SOX10 has emerged as a valuable diagnostic marker for triple-negative breast cancer (TNBC):

• Expression pattern:

  • SOX10 is expressed in a subset of breast carcinomas, primarily in triple-negative breast cancers .

  • In one study, 16.5% of invasive ductal breast carcinomas (18/109) expressed SOX10 .

• Diagnostic utility:

  • SOX10 immunohistochemistry can be used to determine the frequency of expression in TNBC cases .

  • Both percentage of expression and H-score calculation are used for quantification .

• Clinical correlations:

  • SOX10 expression can be correlated with clinicopathological features including:

    • Patient age, tumor size, histological type and grade

    • Nuclear pleomorphism, mitotic count, tumor-infiltrating lymphocytes

    • Necrosis, calcification, lymphovascular invasion

    • Lymph node involvement, T stage, and N stage

• Experimental approaches:

  • Whole slide sections from TNBC specimens can be stained with SOX10 antibody .

  • Chi-square test can be used to assess correlations between SOX10 expression and clinicopathological features .

How does SOX10 function in melanoma tumorigenesis and what are the implications for therapy?

SOX10 plays multiple roles in melanoma development and progression:

• Tumor intrinsic functions:

  • SOX10 knockout reduces cell proliferation of mouse melanoma cells in vitro .

  • SOX10 is required for tumor formation and melanoma cell growth .

• Immune modulation functions:

  • SOX10 regulates immune checkpoint molecules (HVEM, CEACAM1, PD-L1) .

  • SOX10 ablation decreases tumor growth in immune-competent models in a T-cell-dependent manner .

  • SOX10 expression negatively correlates with immune infiltrates in patient databases .

• Therapy resistance:

  • SOX10 loss is sufficient to induce tolerance to BRAF and/or MEK inhibitors .

  • SOX10-deficient melanoma cells show an invasive slow-cycling state .

  • No detectable difference in SOX10 expression is observed after BRAF inhibitor treatment in paired patient biopsies .

• Therapeutic implications:

  • SOX10-deficient cells show a vulnerability based on upregulation of cellular inhibitors of apoptosis-2 (cIAP2) .

  • Targeting SOX10-deficient subpopulations may reduce drug-tolerant populations in melanoma .

  • Combination approaches targeting both SOX10-positive and SOX10-negative subpopulations may be needed for effective therapy.