YNL146C-A Antibody

What is the YY146 antibody and what epitope does it target?

YY146 is a monoclonal antibody that specifically targets human CD146, a cell surface protein found to be highly expressed in high-grade gliomas. The antibody was developed using an improved immunization approach that significantly reduced the production time compared to standard protocols. YY146 shows high binding affinity to CD146-expressing cells and has been validated in multiple cancer cell lines .

The epitope recognized by YY146 is located on the extracellular domain of CD146, making it ideal for both in vitro and in vivo applications. This antibody's high specificity for CD146 enables precise targeting of cancer cells that overexpress this protein, particularly in glioblastoma multiforme (GBM) .

How are neutrophil-specific antibodies like NIMP-R14 validated for research applications?

NIMP-R14, an antibody targeting Ly-6G/Ly-6C, is validated through multiple complementary approaches:

• Flow cytometry validation: Titration experiments (1:10-1:1000 dilution range) to determine optimal antibody concentration for specific neutrophil detection

• Immunohistochemistry verification: Testing on both frozen (1:50 dilution) and paraffin sections (1:50 dilution) to confirm specific staining patterns

• Cross-reactivity testing: Evaluation against multiple species, with validated reactivity in mouse samples and cited reactivity in human samples

• Application-specific validation: Performance testing in different formats including flow cytometry, immunohistochemistry, and immunofluorescence assays

Researchers should perform their own validation when applying these antibodies to new experimental systems, as specificity can vary depending on tissue type and preparation method.

What preservation and storage conditions are recommended for research antibodies?

For optimal antibody performance and longevity, researchers should follow these evidence-based practices:

The absence of sodium azide in the NIMP-R14 antibody makes it particularly suitable for functional assays where azide might interfere with enzymatic activity or cell viability .

What types of cancer show CD146 expression detectable by YY146?

YY146 has been validated for detecting CD146 expression across multiple cancer types:

• High expression observed in:

  • Glioblastoma (particularly WHO grade IV tumors)

  • Malignant melanoma cells (A375)

  • Certain gastric carcinoma specimens

  • Selected ovarian adenocarcinoma samples

  • Some hepatocellular carcinoma tissues

  • Specific lung carcinoma specimens

• Variable expression in cell lines:

  • High expression: U87MG (glioblastoma)

  • Low/marginal expression: U251 (glioblastoma)

  • Differential expression across H460 and H358 (lung), SW480 (colon), MD-MB-231 and MCF-7 (breast), SGC-7901 (gastric), CAOV-3 and SKOV-3 (ovary), and HepG2 and Huh-7 (liver) cell lines

Importantly, CD146 expression strongly correlates with higher tumor grade across multiple cancer types, suggesting its potential value as a biomarker for aggressive malignancies .

How can YY146 be radiolabeled for in vivo immunoPET imaging of glioblastomas?

The process of developing YY146 for immunoPET imaging involves several critical steps:

• Antibody production: Generation of anti-CD146 monoclonal antibody using a fast immunization approach involving B cells harvested from popliteal lymph nodes of immunized mice

• Clone selection: Identification of high-affinity clones through ELISA screening, SDS/PAGE analysis, and immunofluorescence staining of CD146-overexpressing cells (e.g., A375 melanoma cells)

• Radiolabeling procedure:

  • Conjugation of YY146 with a copper-chelating agent

  • Radiolabeling with 64Cu to create 64Cu-labeled YY146

  • Purification of the radiolabeled antibody

  • Quality control testing for radiochemical purity and immunoreactivity

• Validation in animal models:

  • The radiolabeled antibody accumulates preferentially in U87MG xenografts (high CD146 expression)

  • Enables high-contrast PET imaging of small tumor nodules (~2 mm)

  • Shows correlation between tumor uptake and CD146 expression levels

  • Demonstrates specificity for CD146-expressing tissues

This approach provides a non-invasive method for visualizing CD146-expressing tumors, with potential applications in patient stratification and treatment monitoring.

What is the relationship between CD146 expression and cancer stem cell (CSC) properties in glioblastoma?

Research using YY146 has revealed important connections between CD146 expression and cancer stem cell properties:

These findings suggest CD146 may be a marker for identifying and targeting cancer stem cell-like populations in glioblastoma.

How does YY146 affect epithelial-to-mesenchymal transition (EMT) in glioblastoma cells?

YY146 has demonstrated capability to modulate epithelial-to-mesenchymal transition processes in glioblastoma cells:

• Targeting EMT-positive populations:

  • YY146 can selectively target CD146-enriched subpopulations of U87MG cells that display EMT characteristics

  • FACS sorting and subsequent analysis confirms the association between CD146 expression and EMT markers

• Reversal of EMT phenotype:

  • Treatment with YY146 has been shown to mitigate aggressive EMT phenotypes in U87MG cells

  • This suggests that targeting CD146 may help counteract the mesenchymal transformation associated with more aggressive tumor behavior

• Mechanism of action:

  • YY146 likely interferes with signaling pathways that promote EMT

  • The antibody might block interactions between CD146 and its ligands that would otherwise facilitate mesenchymal-like behavior

  • Downstream effects include potential alterations in cell migration, invasion, and resistance to therapy

These findings suggest that YY146 could serve as both a diagnostic tool for identifying tumors with EMT characteristics and a therapeutic agent for targeting and reversing these aggressive phenotypes.

What is the correlation between CD146 expression and WHO tumor grades in gliomas?

A comprehensive histopathological analysis using YY146 as the primary antibody has revealed significant correlations between CD146 expression and glioma grades:

This correlation validates the clinical relevance of CD146 as a biomarker for high-grade gliomas and supports its potential utility in patient stratification for targeted therapies.

What methodological approaches are optimal for using NIMP-R14 in neutrophil research?

For researchers studying neutrophils, the NIMP-R14 antibody offers versatile applications with specific methodological considerations:

The antibody has been particularly effective in animal models studying pneumococcal infection and influenza A co-infection, allowing visualization of neutrophil infiltration in lung tissues .

How can antibodies like YY146 and NIMP-R14 be integrated into comprehensive immunoprofiling of the tumor microenvironment?

A multi-antibody approach to tumor microenvironment analysis provides valuable insights into tumor-immune interactions:

• Complementary targets:

  • YY146 targets CD146 on tumor cells and potentially tumor-associated vasculature

  • NIMP-R14 identifies neutrophil infiltration in the tumor microenvironment

  • Combined use allows simultaneous visualization of tumor cells and neutrophil response

• Multiplex immunohistochemistry protocol:

  • Sequential staining with primary antibodies of different isotypes (YY146: rat IgG; NIMP-R14: rat IgG2b)

  • Detection with isotype-specific secondary antibodies conjugated to different fluorophores

  • Counterstaining with nuclear dyes and additional markers (e.g., CD31 for vessels)

• Spatial relationship analysis:

  • Quantification of neutrophil density in relation to CD146-expressing tumor regions

  • Assessment of neutrophil infiltration patterns in high vs. low CD146-expressing areas

  • Correlation with clinical outcomes and treatment responses

• Application in research models:

  • Has been successfully used in mouse models of influenza and pneumococcal co-infection

  • Potential application in studying immune responses in glioblastoma and other solid tumors

This integrated approach provides a more comprehensive understanding of tumor-immune interactions than single-marker analyses.

What are the considerations for developing therapeutic antibodies based on research antibodies like YY146?

Transitioning from research antibodies to therapeutic agents involves several critical considerations:

• Target validation and mechanism understanding:

  • YY146's ability to target CD146-enriched cancer stem cell-like and EMT-positive populations provides strong rationale

  • Understanding of CD146's correlation with tumor grade supports patient stratification strategies

  • Mechanism of action studies suggest potential therapeutic benefits beyond just targeting

• Antibody engineering requirements:

  • Humanization to reduce immunogenicity

  • Fc optimization for desired effector functions (ADCC, CDC, etc.)

  • Consideration of antibody fragments or bispecific formats for improved tumor penetration

  • Potential for antibody-drug conjugate development

• Preclinical to clinical translation pathway:

  • In vitro efficacy: Demonstrated for YY146 in reducing CSC and EMT phenotypes

  • In vivo models: Validated for imaging; needs expansion to therapeutic endpoints

  • Toxicology: Must assess off-tumor binding (e.g., to normal vasculature expressing CD146)

  • Clinical trial design: Would likely target recurrent glioblastoma with confirmed CD146 expression

• Companion diagnostic development:

  • 64Cu-labeled YY146 already shows promise as an imaging agent

  • Could serve as companion diagnostic to identify patients with CD146-high tumors

  • Integration with conventional imaging to guide surgical and radiation planning

The potential for YY146-based targeted therapies (alone or in combination with other drugs, radioimmunotherapy, or as antibody-drug conjugates) represents a promising approach for personalized medicine in glioblastoma treatment.

What validation steps are essential when applying antibodies like YY146 or NIMP-R14 to new experimental systems?

When adapting antibodies to new research contexts, comprehensive validation is crucial:

• Positive and negative control selection:

  • For YY146: Use U87MG (high CD146) and U251 (low CD146) as glioblastoma controls

  • For NIMP-R14: Use BALB/c mouse neutrophils as positive controls

  • Include appropriate isotype controls matched to the primary antibody

• Cross-reactivity assessment:

  • Test on multiple cell lines or tissues with known target expression profiles

  • Verify specificity using knockdown/knockout approaches where possible

  • For NIMP-R14, note specific reactivity to murine Ly-6G and Ly-6C

• Application-specific optimization:

  • Flow cytometry: Titrate antibody concentrations (e.g., 1:10-1:1000 for NIMP-R14)

  • IHC-Paraffin: Optimize antigen retrieval methods and antibody concentration (e.g., 1:50 for NIMP-R14)

  • IHC-Frozen: Test different fixation protocols to preserve epitope recognition

  • IF/ICC: Determine optimal cell permeabilization conditions

• Multi-method confirmation:

  • Validate findings using complementary techniques (e.g., flow cytometry, Western blot, IHC)

  • Confirm specific binding through competition assays with recombinant target protein

  • For therapeutic applications, verify functional effects beyond just binding

Following these validation steps ensures reliable and reproducible results when implementing these antibodies in new experimental systems.

How can researchers optimize immunohistochemistry protocols for challenging antigens like CD146 in brain tumor specimens?

Optimizing IHC protocols for brain tumor specimens requires addressing specific technical challenges:

• Tissue preparation considerations:

  • Fixation timing: Limit to 24-48 hours to prevent over-fixation and epitope masking

  • Optimal fixative: 10% neutral buffered formalin preserves CD146 epitopes

  • Section thickness: 4-5 μm sections provide optimal staining results

  • Storage of unstained slides: Use within 2 weeks or store at -20°C to prevent epitope degradation

• Antigen retrieval optimization:

  • Heat-induced epitope retrieval (HIER) methods work best for CD146

  • Buffer comparison: Citrate buffer (pH 6.0) vs. EDTA buffer (pH 9.0) - test both

  • Pressure cooker vs. microwave vs. water bath methods - compare for your specific samples

  • Duration optimization: Test 10, 20, and 30-minute retrieval times

• Background reduction strategies:

  • Brain-specific considerations: Block endogenous peroxidase with H₂O₂ treatment

  • Autofluorescence: Consider Sudan Black B treatment for fluorescent detection

  • Endogenous biotin: Use biotin-free detection systems

  • Non-specific binding: Include BSA or serum from the same species as secondary antibody

• Detection system selection:

  • For low expression: Use polymer-based or tyramide signal amplification

  • For co-localization: Apply sequential multiplex protocols

  • For quantification: Ensure linear dynamic range of detection method

  • For problematic samples: Consider extending primary antibody incubation to overnight at 4°C

These optimizations have been validated through the successful detection of CD146 in a cohort of 56 patients with various WHO grade gliomas, demonstrating reliable staining patterns that correlate with tumor grade.

How might CD146-targeting antibodies like YY146 be integrated into glioblastoma treatment strategies?

The integration of CD146-targeting antibodies into glioblastoma treatment presents several promising strategies:

• Patient stratification applications:

  • 64Cu-labeled YY146 PET imaging could identify patients with high CD146 expression

  • This would allow selection of patients most likely to benefit from CD146-targeted therapies

  • The correlation between CD146 expression and high tumor grade provides clinical rationale for this approach

• Therapeutic modalities:

  • Naked antibody therapy: YY146 alone has shown ability to target CSC and EMT phenotypes

  • Antibody-drug conjugates: Coupling YY146 with cytotoxic payloads

  • Radioimmunotherapy: Using radiolabeled YY146 for targeted radiation delivery

  • Combination therapy: Pairing with standard treatments (temozolomide, radiation)

• Addressing tumor heterogeneity:

  • Targeting CD146-high subpopulations that may be responsible for recurrence

  • Combining with other targeted therapies to address multiple tumor subpopulations

  • Sequential treatment strategies based on changing tumor profiles

• Overcoming treatment resistance:

  • Targeting CD146-associated EMT may help overcome resistance to standard therapies

  • Addressing CSC-like populations may reduce tumor recurrence

  • Combination with immune checkpoint inhibitors could enhance immune recognition

Clinical translation would require further preclinical studies demonstrating therapeutic efficacy beyond the current imaging and in vitro functional data, but the existing evidence provides a strong foundation for continued development.

What emerging applications exist for neutrophil-targeting antibodies in cancer research?

Neutrophil-targeting antibodies like NIMP-R14 are finding innovative applications in cancer research:

• Tumor microenvironment characterization:

  • Quantifying neutrophil infiltration patterns in different tumor regions

  • Correlating neutrophil density with prognosis and treatment response

  • Identifying neutrophil-tumor cell interactions through multiplex imaging

  • Distinguishing tumor-associated neutrophil (TAN) phenotypes (N1 anti-tumor vs. N2 pro-tumor)

• Therapeutic manipulation approaches:

  • Selective depletion of pro-tumor neutrophil populations

  • Blocking neutrophil recruitment to tumor sites

  • Reprogramming neutrophils from pro-tumor to anti-tumor phenotypes

  • Combining with immune checkpoint inhibitors to enhance immunotherapy

• Model system applications:

  • Monitoring treatment-induced changes in neutrophil recruitment

  • Studying neutrophil extracellular traps (NETs) in cancer progression

  • Investigating neutrophil-mediated drug resistance mechanisms

  • Neutrophil-based drug delivery strategies

• Clinical translation potential:

  • Development of humanized versions for clinical studies

  • Companion diagnostics to measure neutrophil infiltration

  • Predictive biomarkers for immunotherapy response

  • Novel therapeutic targets based on neutrophil biology

These approaches highlight the evolving understanding of neutrophils not just as passive responders but as active participants in cancer biology that can be therapeutically targeted.