BCL2 (Ab-56) Antibody

What is BCL2 (Ab-56) Antibody and what are its main applications?

BCL2 (Ab-56) Antibody is a rabbit polyclonal antibody that specifically recognizes endogenous levels of total BCL-2 protein in human samples. It was produced by immunizing rabbits with a synthetic peptide-KLH conjugate and purified using affinity chromatography with epitope-specific peptides .

The main applications of this antibody include:

• Western blotting (WB) at dilutions of 1:500-1:1000

• Immunohistochemistry (IHC) at dilutions of 1:50-1:100

• Immunofluorescence (IF) at dilutions of 1:100-1:200

This antibody is particularly valuable for detecting BCL-2 protein expression in cancer research, apoptosis studies, and clinical diagnostics. Experimental validation has confirmed its reactivity with human samples, including cell lines such as HeLa, A2780, and 293 cells, as well as human breast carcinoma tissue .

What is the molecular basis of BCL2 function and why is its detection important in research?

BCL2 (B-cell lymphoma 2) is a critical regulator of programmed cell death or apoptosis. It functions by suppressing apoptosis in various cell systems including lymphohematopoietic and neural cells. At the molecular level, BCL2 regulates cell death by controlling mitochondrial membrane permeability and operates in a feedback loop system with caspases .

The protein inhibits caspase activity through two main mechanisms:

• Preventing the release of cytochrome c from mitochondria

• Binding to the apoptosis-activating factor (APAF-1)

Detection of BCL2 expression is crucial in research because:

• Dysregulated BCL2 expression is associated with numerous pathological conditions, particularly cancer

• BCL2 overexpression contributes to treatment resistance in many cancers

• BCL2 status can serve as a prognostic marker in diffuse large B-cell lymphoma (DLBCL) and other malignancies

• New anti-BCL2 therapies are being developed, making accurate detection of BCL2 expression essential for patient selection

How does BCL2 (Ab-56) Antibody compare to other commercially available BCL2 antibodies?

BCL2 (Ab-56) Antibody differs from other commercially available BCL2 antibodies primarily in its epitope recognition and performance characteristics. While BCL2 (Ab-56) targets amino acids 54-58 (G-H-T-P-H) of human BCL2 , other common antibodies target different epitopes:

• Clone 124 (mouse monoclonal): Targets N-terminus amino acids 41-54

• Clone SP66 (rabbit monoclonal): Targets N-terminus amino acids 40-75

• Clone E17 (rabbit monoclonal): Targets N-terminus amino acids 61-76

These differences in epitope targeting significantly affect detection efficiency. Research has shown that in DLBCL tissues, SP66 (80% positive) and E17 (62% positive) detect BCL2 expression more frequently than clone 124 (34% positive) . This discrepancy is clinically significant as clone 124 frequently fails to detect BCL2 expression in translocation-positive and amplification-positive DLBCL cases where high levels of BCL2 protein are expected .

What are the optimal storage and handling conditions for BCL2 (Ab-56) Antibody?

For optimal performance and longevity of BCL2 (Ab-56) Antibody, adherence to specific storage and handling protocols is essential:

Storage conditions:

• Long-term storage: -20°C (recommended)

• Short-term storage: 4°C

• Avoid repeated freeze-thaw cycles which can degrade antibody quality and performance

Formulation details:

• The antibody is supplied at a concentration of 1.0mg/mL

• Formulated in phosphate buffered saline (without Mg²⁺ and Ca²⁺), pH 7.4

• Contains 150mM NaCl, 0.02% sodium azide, and 50% glycerol

When handling the antibody for experiments, it's advisable to:

• Briefly centrifuge the antibody vial before opening to bring down solution

• Aliquot the antibody upon first thaw to minimize freeze-thaw cycles

• When diluting, use clean tubes and pipettes to prevent contamination

• Keep on ice during experimental procedures

• Wear gloves when handling due to the presence of sodium azide, which is toxic

Following these guidelines will help maintain antibody integrity and ensure consistent experimental results.

What are the recommended protocols for using BCL2 (Ab-56) Antibody in different applications?

Western Blotting Protocol (1:500-1:1000 dilution):

• Prepare protein extracts from cells or tissues of interest

• Separate proteins by SDS-PAGE (note that BCL2 has a predicted molecular weight of 26kD)

• Transfer proteins to a membrane (PVDF or nitrocellulose)

• Block with 5% non-fat milk or BSA in TBST

• Incubate with BCL2 (Ab-56) Antibody (1:500-1:1000) overnight at 4°C

• Wash with TBST (3-5 times, 5-10 minutes each)

• Incubate with HRP-conjugated secondary antibody

• Wash and develop using chemiluminescence detection

Immunohistochemistry Protocol (1:50-1:100 dilution):

• Prepare paraffin sections of tissue samples (4μm thickness recommended)

• Deparaffinize and rehydrate sections

• Perform antigen retrieval (heat-induced epitope retrieval recommended)

• Block endogenous peroxidase and non-specific binding

• Incubate with BCL2 (Ab-56) Antibody (1:50-1:100) for 1-2 hours at room temperature or overnight at 4°C

• Wash sections and apply appropriate detection system

• Counterstain, dehydrate, and mount

Immunofluorescence Protocol (1:100-1:200 dilution):

• Fix cells (4% paraformaldehyde or methanol fixation)

• Permeabilize cells if necessary (0.1-0.5% Triton X-100)

• Block with appropriate blocking buffer

• Incubate with BCL2 (Ab-56) Antibody (1:100-1:200) overnight at 4°C

• Wash cells thoroughly

• Apply fluorophore-conjugated secondary antibody

• Counterstain nuclei and mount with appropriate mounting medium

Successful use of this antibody has been demonstrated in HeLa cells by immunofluorescence and in human breast carcinoma tissue by immunohistochemistry .

What control samples should be used when working with BCL2 (Ab-56) Antibody?

When working with BCL2 (Ab-56) Antibody, appropriate controls are essential for validating results and ensuring experimental rigor:

Positive Controls:

• Cell lines with known BCL2 expression: HeLa, A2780, and 293 cells have been validated for Western blotting

• Tissue samples: Human breast carcinoma tissue has been validated for immunohistochemistry

• Normal human tonsil tissue: Mantle zone B cells and interfollicular T cells express BCL2, while germinal center B cells are typically negative

Negative Controls:

• Blocking peptide control: Pre-incubation of the antibody with its specific blocking peptide abolishes positive staining, confirming specificity

• Primary antibody omission: Replace primary antibody with antibody dilution buffer

• Isotype control: Use matched isotype antibody at the same concentration

Specificity Controls:

• Western blot should yield a band at approximately 26kD (predicted molecular weight of BCL2)

• For immunohistochemistry, staining pattern should match known BCL2 expression patterns (e.g., positive in mantle zone B cells and negative in germinal center B cells in tonsil)

Including these controls helps distinguish true positive signals from background or non-specific staining, ensuring reliable and reproducible results.

Why might BCL2 (Ab-56) Antibody show different staining patterns compared to other BCL2 antibodies?

The discrepancies in staining patterns between BCL2 (Ab-56) Antibody and other BCL2 antibodies can be attributed to several factors:

Epitope differences:
BCL2 (Ab-56) Antibody targets amino acids 54-58 (G-H-T-P-H) , while other antibodies such as clone 124, E17, and SP66 target different epitope regions . These epitope differences can significantly affect antibody binding capabilities.

Post-translational modifications:
Research has shown that phosphorylation of BCL2 at T69 and/or S70 can interfere with antibody binding, particularly for clone 124, resulting in false-negative staining. This modification occurs more frequently in cases with discrepant staining between antibodies .

Mutations in the BCL2 gene:
Mutations within the epitope region can prevent antibody recognition. While mutations in BCL2 have been linked to false-negative results with clone 124 in DLBCL cell lines with t(14;18), they don't account for all false-negative cases .

Variable BCL2 expression levels:
Different antibodies may have different sensitivity thresholds. In DLBCL tissues, SP66 (80%) and E17 (62%) detect BCL2 expression more frequently than clone 124 (34%) .

Understanding these factors is crucial when interpreting discrepant results between different BCL2 antibodies and may guide the selection of the most appropriate antibody for specific research questions.

How can false-negative results be minimized when detecting BCL2 in diffuse large B-cell lymphoma (DLBCL)?

To minimize false-negative results when detecting BCL2 in DLBCL, researchers should consider the following strategies:

Use of alternative BCL2 antibodies:
Studies have shown that rabbit monoclonal antibodies E17 and SP66 detect BCL2 expression more frequently than the standard mouse monoclonal 124 clone in DLBCL tissues . Using multiple antibodies targeting different epitopes can provide more comprehensive detection.

Antibody selection based on DLBCL subtype:

• For activated B-cell (ABC) DLBCL: Clone 124 frequently fails to detect BCL2 in these cases despite expected high expression levels

• For translocation-positive DLBCL: SP66 or E17 antibodies show superior detection

Correlation with genetic analysis:
Integrate antibody staining results with genetic analysis such as:

• Dual in-situ hybridization (Dual ISH) to detect BCL2 translocation and amplification

• mRNA expression analysis to confirm protein expression findings

Optimization of staining protocols:

• Extended antigen retrieval may improve detection of phosphorylated BCL2

• Testing different fixation methods can minimize epitope masking

• Adjusting antibody concentration and incubation time for optimal signal-to-noise ratio

Assessment criteria standardization:

• Use a consistent cut-off value (e.g., ≥30% positive cells) for BCL2 positivity

• Document staining intensity and pattern in addition to percentage of positive cells

Implementing these approaches will enhance detection accuracy and reduce false-negative results in DLBCL cases, leading to improved patient stratification and treatment selection.

What advanced techniques can be combined with BCL2 (Ab-56) antibody staining for more comprehensive analysis?

Combining BCL2 (Ab-56) antibody staining with advanced techniques provides more comprehensive insights into BCL2 biology and its clinical implications:

Dual immunohistochemistry/immunofluorescence:
Simultaneously detect BCL2 alongside other proteins such as MYC to identify "double-expressor" lymphomas, which have poorer prognosis. This technique allows assessment of co-expression patterns at the single-cell level .

Dual in-situ hybridization (Dual ISH):
This technique detects both BCL2 gene translocation and amplification, providing genetic context to protein expression data. Dual ISH has revealed a higher amplification frequency of BCL2 than previously reported using fluorescence ISH, suggesting BCL2 amplification may be under-reported in DLBCL .

Phosphorylation status assessment:
Combining BCL2 staining with phospho-specific antibodies targeting T69 and/or S70 can identify cases where post-translational modifications might affect antibody binding and therapeutic responses .

Multiplex immunohistochemistry:
This technology allows simultaneous detection of multiple biomarkers on a single tissue section, enabling comprehensive profiling of the tumor microenvironment and identifying clinically relevant subgroups.

Integration with molecular profiling:

• RNA sequencing to correlate protein expression with transcript levels

• Whole-exome sequencing to identify mutations affecting antibody binding

• Proteomic analysis to assess BCL2 interaction partners

Tissue microarray (TMA) analysis:
This high-throughput approach enables evaluation of BCL2 expression across large cohorts, facilitating correlation with clinical outcomes and identification of prognostic subgroups.

These advanced techniques, when combined with BCL2 (Ab-56) antibody staining, provide a multi-dimensional view of BCL2 biology and its clinical significance, enhancing both basic research and clinical applications.

How does BCL2 (Ab-56) Antibody performance correlate with BCL2 gene status in lymphoma?

BCL2 (Ab-56) Antibody performance shows important correlations with BCL2 gene status in lymphoma, particularly regarding translocation and amplification events:

BCL2 translocation detection:
While specific data for BCL2 (Ab-56) Antibody is not provided in the search results, research with other BCL2 antibodies provides valuable insights. The standard 124 clone frequently fails to detect BCL2 protein in translocation-positive DLBCL cases, whereas SP66 and E17 antibodies show superior detection in these cases . When selecting antibodies for translocation-positive cases, researchers should consider antibodies targeting epitopes outside the commonly mutated regions.

BCL2 amplification correlation:
Dual in-situ hybridization (Dual ISH) has revealed a higher frequency of BCL2 amplification than previously reported with fluorescence ISH, suggesting this genetic alteration may be under-reported in DLBCL . Antibodies that detect BCL2 protein in amplification-positive cases are critical for accurate assessment of these tumors.

Relationship to false-negative staining:
Cases with discrepant staining between different BCL2 antibodies often show complex genetic alterations. Mutations within the epitope region recognized by certain antibodies can prevent binding, resulting in false-negative results despite high BCL2 expression at the transcript level .

Understanding these correlations is essential for selecting the appropriate antibody in research and clinical settings, particularly when studying lymphomas with known or suspected BCL2 genetic alterations.

What is the significance of BCL2 detection in the context of MYC expression and "double-hit" lymphomas?

BCL2 detection has significant implications when evaluated alongside MYC expression, particularly in identifying high-risk "double-hit" and "double-expressor" lymphomas:

Identification of "double-hit" lymphomas:
"Double-hit" lymphomas harbor concurrent translocations of MYC and BCL2, representing a distinct high-risk category in the WHO classification. Accurate detection of BCL2 protein expression, particularly in cases with BCL2 translocation, is crucial for identifying these aggressive lymphomas.

"Double-expressor" phenotype:
Even without genetic translocations, co-expression of BCL2 and MYC proteins (double-expressor phenotype) confers poor prognosis in DLBCL. Reliable antibodies for both proteins are essential for accurate classification.

Therapeutic relevance:

• BCL2 inhibitors (e.g., venetoclax) show promise in BCL2-positive lymphomas

• Cases with concurrent BCL2 and MYC expression may require intensive therapeutic approaches

• Accurate detection of both proteins guides treatment selection

Antibody selection considerations:
For optimal detection of double-expressor lymphomas, the choice of BCL2 antibody is critical. Research indicates that SP66 demonstrates the strongest correlation with clinical outcomes in the context of MYC expression .

Understanding the interplay between BCL2 and MYC expression has transformed lymphoma classification and treatment approaches, emphasizing the need for reliable and accurate detection methods for both proteins.

How can BCL2 (Ab-56) Antibody be used in assessing response to BCL2-targeted therapies?

BCL2 (Ab-56) Antibody can play a crucial role in assessing response to BCL2-targeted therapies through several applications:

Pre-treatment patient selection:
BCL2 protein expression detected by immunohistochemistry helps identify patients likely to respond to BCL2-targeted therapies like venetoclax (ABT-199). Accurate detection is essential for patient selection, as false-negative results could exclude potentially responsive patients .

Monitoring therapy-induced changes:
Serial biopsies during treatment can be stained with BCL2 (Ab-56) Antibody to monitor changes in BCL2 expression levels, which may correlate with treatment response or resistance development.

Resistance mechanism identification:
When resistance develops, analysis of BCL2 expression alongside other BCL2 family members (e.g., MCL1, BCL-XL) can help identify compensatory mechanisms. This might include:

• Post-translational modifications of BCL2

• Upregulation of other anti-apoptotic proteins

• Mutations in the BCL2 gene affecting drug binding

Complementary assays for comprehensive assessment:
For optimal therapeutic monitoring, BCL2 (Ab-56) Antibody staining should be combined with:

• Functional apoptosis assays (e.g., BH3 profiling)

• Gene expression analysis of BCL2 family members

• Assessment of BCL2 phosphorylation status, which can affect drug efficacy

Research applications:
In research settings, the antibody can be used to study mechanisms of action and resistance in preclinical models, facilitating the development of next-generation BCL2 inhibitors or combination strategies.

The accurate detection of BCL2 expression is increasingly important as targeted therapies entering clinical practice require precise biomarker assessment for optimal patient selection and response monitoring .

What are the emerging applications of BCL2 (Ab-56) Antibody in cancer research beyond lymphoma?

While BCL2 research has historically focused on lymphoma, BCL2 (Ab-56) Antibody has emerging applications across multiple cancer types and research areas:

Solid tumor research:
BCL2 (Ab-56) Antibody has been validated for immunohistochemical detection in human breast carcinoma tissue , highlighting its utility in solid tumor research. BCL2 overexpression has been implicated in various solid malignancies including:

• Breast cancer (particularly hormone receptor-positive subtypes)

• Small cell lung cancer

• Prostate cancer

• Neuroblastoma

• Melanoma

Apoptosis resistance mechanisms:
BCL2 plays a central role in apoptosis regulation by controlling mitochondrial membrane permeability . The antibody helps investigate how cancer cells evade apoptosis, a hallmark capability of cancer.

Therapeutic resistance studies:
BCL2 expression correlates with resistance to various therapies including:

• Conventional chemotherapy

• Radiation therapy

• Targeted therapies

• Immunotherapies

Cancer stem cell biology:
BCL2 contributes to cancer stem cell survival and therapy resistance. BCL2 (Ab-56) Antibody can help identify and study these therapy-resistant subpopulations.

Tumor microenvironment interactions:
BCL2 expression in tumor cells influences interactions with the microenvironment. Multiplex staining incorporating BCL2 (Ab-56) Antibody can reveal these complex interactions.

Liquid biopsy development:
Detecting BCL2 protein in circulating tumor cells could serve as a biomarker in liquid biopsy approaches, potentially offering less invasive monitoring methods.

These emerging applications demonstrate the expanding utility of BCL2 (Ab-56) Antibody beyond its traditional role in lymphoma research, contributing to a broader understanding of cancer biology and therapeutic resistance.

How might advances in antibody technology improve BCL2 detection methods in the future?

Several technological advances are poised to enhance BCL2 detection methods in the coming years:

Single-cell analysis technologies:
Integration of BCL2 antibodies with single-cell technologies will enable more granular analysis of heterogeneous samples, revealing subpopulations with distinct BCL2 expression patterns and functional states.

Recombinant antibody engineering:
Development of recombinant antibodies with precisely defined epitopes could reduce batch-to-batch variation and improve standardization. This approach may yield antibodies that:

• Detect specific BCL2 conformations

• Recognize post-translationally modified BCL2

• Maintain specificity despite mutations in the target protein

Multiplexed detection platforms:
Advanced multiplexing technologies will allow simultaneous detection of BCL2 alongside dozens of other proteins, providing comprehensive insights into signaling networks. These include:

• Imaging mass cytometry

• Cyclic immunofluorescence

• Digital spatial profiling

Phosphorylation-state specific antibodies:
As phosphorylation at T69 and/or S70 affects BCL2 detection and function , development of phosphorylation-state specific antibodies will provide valuable insights into BCL2 regulation.

Antibody-drug conjugates:
Beyond detection, BCL2 antibodies may be engineered as delivery vehicles for cytotoxic payloads, creating targeted therapeutic approaches.

In vivo imaging applications:
Labeled BCL2 antibodies or antibody fragments could enable in vivo imaging of BCL2 expression in preclinical models and potentially in clinical settings.

AI-enhanced image analysis:
Artificial intelligence algorithms will improve quantification of BCL2 staining, standardize interpretation, and identify novel correlations between staining patterns and clinical outcomes.

These technological advances will address current limitations in BCL2 detection, providing more accurate, sensitive, and informative methods for both research and clinical applications.

What validation techniques should be employed when using BCL2 (Ab-56) Antibody in novel experimental systems?

When applying BCL2 (Ab-56) Antibody to novel experimental systems, comprehensive validation is essential to ensure reliability and reproducibility:

Expression system validation:

• Western blotting: Confirm antibody detects a single band at the expected molecular weight (26kDa) in the novel system

• Positive and negative controls: Include cell lines with known BCL2 expression levels (e.g., HeLa, A2780, and 293 cells)

• BCL2 knockout/knockdown controls: Use CRISPR/Cas9 or siRNA approaches to generate negative controls

Epitope blocking experiments:
Pre-incubate the antibody with its specific blocking peptide before staining to confirm specificity in the new system. This should abolish positive staining, as demonstrated in human breast carcinoma tissue .

Cross-reactivity assessment:
Test antibody performance in:

• Multiple cell types relevant to the experimental question

• Related species if working with non-human models

• Different fixation and sample preparation methods

Orthogonal detection methods:
Confirm BCL2 expression using independent techniques:

• mRNA detection (RT-PCR, RNA-seq, or in situ hybridization)

• Alternative BCL2 antibodies targeting different epitopes

• Mass spectrometry-based protein detection

Functional correlation:
Correlate antibody staining with functional BCL2 assays:

• BH3 profiling

• Cytochrome c release assays

• Apoptosis resistance phenotypes

Multi-antibody comparison:
Compare results with other BCL2 antibodies (e.g., 124, E17, SP66) to identify potential discrepancies and determine the most suitable antibody for the specific application .

Reproducibility assessment:
Test antibody performance across:

• Different antibody lots

• Multiple researchers

• Various experimental conditions

Implementing these validation strategies ensures that findings generated with BCL2 (Ab-56) Antibody in novel experimental systems are robust, reliable, and scientifically sound.