CCR3 Antibody

What is CCR3 and what cell types express it?

CCR3 is a G protein-coupled receptor that serves as a receptor for multiple CC chemokines, including CCL5/RANTES, CCL7/MCP-3, and CCL11/eotaxin. Expression profiling demonstrates that CCR3 is prominently expressed on the surface of eosinophils, basophils, a subset of Th2 lymphocytes, mast cells, and airway epithelial cells . In human tissues, CCR3 has been confirmed in multiple sample types with validated expression in:

The cellular localization is typically in the cell membrane, consistent with its function as a chemokine receptor mediating cell migration and inflammatory responses .

How should I select the appropriate anti-CCR3 antibody for my specific research application?

Selection of the appropriate anti-CCR3 antibody requires careful consideration of multiple experimental parameters:

• Species specificity: Ensure the antibody is reactive to your species of interest. For example, antibodies targeting human CCR3 may not cross-react with mouse CCR3 due to sequence variations. The epitope differences between species can be significant - human CCR3 antibodies like PA2176 target specific N-terminal sequences (MTTSLDTVETFGTTSYYDDV) , while mouse-specific antibodies recognize different epitopes.

• Application compatibility: Verify the antibody has been validated for your specific application:

  • For IHC/ICC: Look for antibodies with demonstrated membrane staining pattern

  • For WB: Confirm the expected molecular weight (~41 kDa) and validated lysate types

  • For flow cytometry: Check for surface staining capacity and optimized protocols

• Clone characteristics: For monoclonal antibodies, identify the specific epitope recognized. N-terminal targeting antibodies (amino acids 1-38) like C3Mab-3 and C3Mab-4 have shown high specificity and defined binding characteristics through alanine scanning studies .

• Validation data: Request and review actual validation images for your application and tissue type before proceeding with experiments.

When working with human samples, antibodies like PA2176 (rabbit polyclonal) have been validated for IHC, ICC and WB applications , while mouse studies often utilize clones like BioLegend's AB_2715914 (Cat. No. 144502) .

What are the optimal storage and handling conditions for CCR3 antibodies?

Proper storage and handling are critical for maintaining antibody functionality and experimental reproducibility:

Most commercial CCR3 antibodies are provided in lyophilized form and require careful reconstitution. For optimal stability and functionality:

• Storage before reconstitution: Store lyophilized antibody at -20°C upon receipt. Most formulations remain stable for at least one year at this temperature .

• Reconstitution protocol:

  • Use sterile techniques in a clean environment

  • Reconstitute only with recommended buffers (typically PBS or manufacturer-provided buffers)

  • Allow the vial to equilibrate to room temperature before opening

  • Ensure complete dissolution by gentle mixing (avoid vortexing)

• Post-reconstitution storage:

  • Short-term storage (≤1 month): 4°C

  • Long-term storage: Aliquot and store at -20°C to minimize freeze-thaw cycles

  • Avoid more than 5 freeze-thaw cycles, as this significantly reduces antibody activity

• Working solution preparation:

  • Dilute only the amount needed for immediate use

  • Use appropriate diluents (typically containing 1-5% BSA or serum)

  • For IHC applications, diluent optimization may be required for different tissue types

According to manufacturer specifications, reconstituted CCR3 antibodies typically maintain activity for at least one month at 4°C and up to six months when properly aliquoted and stored at -20°C .

What positive and negative controls should I use when validating a CCR3 antibody?

Proper control selection is essential for antibody validation and ensuring experimental rigor:

Positive controls:

• Cell lines: K562 and Raji cell lysates have been validated as positive controls for human CCR3 Western blotting .

• Tissue samples:

  • Human tonsil tissue shows reliable CCR3 expression for IHC validation

  • Blood samples from healthy donors (for flow cytometry)

  • Synovium samples show consistent CCR3 expression

• Recombinant systems: HEK293 cells transfected with CCR3 expression constructs provide a defined positive control system

Negative controls:

• Antibody-specific:

  • Isotype control antibodies matched to the CCR3 antibody class and host species

  • Pre-incubation with blocking peptide (when available) should abolish specific staining

  • Secondary antibody-only controls to assess background

• Sample-specific:

  • Cell lines known to lack CCR3 expression

  • Tissues from CCR3 knockout models (for animal studies)

  • Normal lung tissues typically show minimal CCR3 expression compared to allergic models

Validation data interpretation:

• For IHC/ICC: Expect membrane-localized staining pattern with minimal cytoplasmic signal

• For WB: A single band at approximately 41 kDa indicates specificity

• For flow cytometry: Compare signal intensity to isotype controls and verify with blocking experiments

How can I determine the exact epitope recognized by my anti-CCR3 antibody, and why is this important for experimental design?

Epitope determination is critical for understanding antibody functionality, predicting cross-reactivity, and designing blocking experiments. Advanced researchers can employ several complementary approaches:

• Extracellular domain substitution analysis:

  • Generate chimeric proteins where regions of CCR3 are replaced with corresponding regions from related receptors

  • Express these constructs in cell lines and assess antibody binding via flow cytometry

  • This approach has successfully identified that antibodies like C3Mab-3, C3Mab-4, and J073E5 recognize the N-terminal region (amino acids 1–38) of mouse CCR3

• Alanine scanning mutagenesis:

  • Systematically replace individual amino acids with alanine in the suspected epitope region

  • Express mutant constructs and assess binding via flow cytometry

  • This technique revealed that Ala2, Phe3, Asn4, and Thr5 are critical for C3Mab-3 binding, while Ala2, Phe3, and Thr5 are essential for C3Mab-4 binding

• Peptide competition assays:

  • Synthesize overlapping peptides spanning the putative epitope region

  • Pre-incubate antibody with peptides before application to target cells/tissues

  • Binding inhibition identifies the peptide containing the epitope

The epitope location has significant experimental implications:

• Functional studies: Antibodies targeting different epitopes may have different neutralizing capabilities

• Cross-reactivity prediction: Sequence alignment of the epitope region across species can predict cross-reactivity

• Compatibility with receptor activation: Antibodies targeting regions involved in ligand binding may block receptor function

For example, knowing that C3Mab-3 binds to Ala2, Phe3, Asn4, and Thr5 of mouse CCR3 allows researchers to predict that this antibody likely blocks interactions with specific chemokines that utilize this region .

What are the critical considerations when using anti-CCR3 antibodies in therapeutic applications versus detection applications?

The transition from detection to therapeutic applications requires additional experimental considerations:

Detection Applications:

• Focus on specificity, signal-to-noise ratio, and reproducibility

• Fixation compatibility and epitope accessibility are primary concerns

• Antibody concentration typically optimized for maximal specific signal

Therapeutic Applications:

• Dosage optimization:

  • Requires systematic dose-response studies (e.g., 5, 10, and 20 μL/mg as used in mouse models)

  • Must balance efficacy with potential side effects

  • Consider pharmacokinetic parameters (half-life, tissue distribution)

• Administration route considerations:

  • Intraperitoneal administration has shown efficacy in mouse models of allergic rhinitis

  • Local administration may provide targeted effects with reduced systemic exposure

  • Administration timing relative to disease onset significantly impacts efficacy

• Efficacy assessment parameters:

  • Clinical manifestations (e.g., scratching, sneezing, breathing patterns)

  • Histological assessment of target tissues

  • Cytokine profile changes (IFN-γ, IL-2, IL-4, IL-5, IL-13)

  • Cell-specific migration and activation

• Off-target considerations:

  • Assess effects on non-target tissues expressing CCR3

  • Monitor for immune complex formation or anti-antibody responses

  • Evaluate long-term impacts on normal immune function

How can I resolve discrepancies between CCR3 antibody detection systems and functional assays in my research?

Discrepancies between antibody-based detection and functional outcomes are common challenges requiring systematic troubleshooting:

• Epitope accessibility versus functional relevance:

  • Antibodies may detect CCR3 but not block all functional interactions

  • Map the specific epitope recognized by your antibody to predict functional impact

  • Antibodies targeting the N-terminal region (aa 1-38) may not affect interactions mediated by other receptor domains

• Receptor conformational states:

  • CCR3 exists in multiple conformational states affecting epitope accessibility

  • Activated versus inactive receptor states may present different binding characteristics

  • Consider using multiple antibodies targeting different epitopes to comprehensively assess receptor status

• Methodological reconciliation approaches:

  Discrepancy Type	Investigation Approach	Resolution Strategy
  Positive staining/Negative function	Competitive binding with known ligands	Test antibody concentration effects on functional assays
  Negative staining/Positive function	Test alternative fixation methods	Use alternative antibody clones targeting different epitopes
  Variable results across sample types	Compare expression levels quantitatively	Optimize protocols specifically for each sample type

• Technical considerations:

  • Ensure antibody hasn't degraded (run parallel tests with fresh antibody)

  • Verify buffer compatibility with functional assays

  • Consider the impact of tags or detection systems on antibody function

  • Temporal dynamics may differ between detection and functional response

One documented example is the detection of CCR3 in monocytes despite variable functional responses to CCR3 ligands - this was resolved by demonstrating receptor expression occurred primarily after specific activation conditions.

What are the most effective techniques for multiplex detection of CCR3 alongside other chemokine receptors and immune markers?

Multiplex detection approaches enable comprehensive characterization of immune cell populations and their functional states:

• Multicolor flow cytometry optimization:

  • Panel design considerations: Choose fluorophores with minimal spectral overlap

  • Titrate antibodies individually before combining into panels

  • Include appropriate compensation controls

  • Consider sequential staining protocols for challenging epitopes

• Mass cytometry (CyTOF) applications:

  • Enables simultaneous detection of >40 parameters without spectral overlap concerns

  • Requires metal-conjugated antibodies

  • Particularly valuable for comprehensive immune phenotyping in complex tissues

• Multiplex immunohistochemistry approaches:

  • Sequential staining with different chromogens

  • Tyramide signal amplification for sensitive detection

  • Multispectral imaging systems for signal separation

• Validated marker combinations for specific cell populations:

  Cell Type	CCR3 Co-markers	Detection Notes
  Eosinophils	CD11b+, Siglec-F+, IL-5Rα+	CCR3 expression high and constitutive
  Th2 cells	CD4+, GATA3+, ST2+	CCR3 expression variable and activation-dependent
  Basophils	CD123+, FcεRI+, CD203c+	Moderate CCR3 expression
  Mast cells	CD117+, FcεRI+, CD203c+	CCR3 expression in tissue-resident populations

• Spatial transcriptomics integration:

  • Combine antibody detection with in situ hybridization for CCR3 mRNA

  • Correlate protein and transcript levels for comprehensive expression analysis

  • Enables detection of regulation at transcriptional versus post-transcriptional levels

These multiplex approaches have revealed previously unappreciated heterogeneity in CCR3 expression across immune cell populations and disease states, particularly in allergic conditions where coordinated expression with other chemokine receptors shapes inflammatory responses.

How can I use anti-CCR3 antibodies to investigate the "one airway, one disease" hypothesis in allergic conditions?

The "one airway, one disease" hypothesis proposes integrated inflammatory responses throughout the respiratory tract in allergic conditions. Anti-CCR3 antibodies provide valuable tools to investigate this concept:

• Comprehensive tissue analysis workflow:

  • Collect matched samples from upper and lower airways

  • Apply standardized staining protocols using validated anti-CCR3 antibodies

  • Quantify CCR3+ cell infiltration, distribution patterns, and co-expression with activation markers

  • Correlate findings between anatomical locations

• Mechanistic investigation approach:

  • Use CCR3 antibodies for both detection and functional blocking

  • Assess CCR3 ligand expression patterns across airway segments

  • Track labeled CCR3+ cells to determine migration patterns between airway compartments

  • Correlate inflammatory mediator profiles between compartments

• Therapeutic targeting validation:

  • Administration of blocking CCR3 antibodies can demonstrate integrated effects across the respiratory tract

  • Research has shown that CCR3 monoclonal antibody treatment improves both nasal mucosa inflammation and lung tissue pathology in allergic models

  • Systematic assessment of dose-dependent effects at multiple anatomical sites provides evidence for unified pathophysiology

• Cellular and molecular correlation data:

  • High expression of Eotaxin and RANTES in both nasal mucosa and lung tissue correlates with eosinophil infiltration in allergic rhinitis models

  • CCR3 antibody treatment reduces inflammatory infiltration in nasal mucosa with corresponding improvements in cytokine profiles (IFN-γ, IL-2, IL-4, IL-5, IL-13)

  • These findings support coordinated inflammatory mechanisms throughout the respiratory tract

The simultaneous improvement of upper and lower airway pathology following CCR3 blockade provides experimental support for the "one airway, one disease" concept, suggesting that targeted therapies may offer comprehensive benefits across the respiratory system in allergic conditions .

What are the optimal fixation and permeabilization protocols for CCR3 detection in different applications?

Optimizing fixation and permeabilization is critical for preserving CCR3 epitopes while enabling antibody access:

• For flow cytometry:

  • Live cell staining: Preferred for surface CCR3 detection

  • Fixation options: 1-2% paraformaldehyde (10 minutes at room temperature)

  • Avoid methanol-based fixatives that can distort membrane protein epitopes

  • If permeabilization is required: 0.1% saponin is preferable to harsher detergents

• For immunohistochemistry:

  • Formalin fixation: 10% neutral buffered formalin (24-48 hours)

  • Antigen retrieval: Citrate buffer (pH 6.0) heat-induced epitope retrieval

  • For frozen sections: 4% paraformaldehyde (10 minutes) followed by permeabilization with 0.2% Triton X-100

  • Blocking: 5% serum from the same species as the secondary antibody

• For Western blotting:

  • Sample preparation: RIPA buffer with protease inhibitors

  • Denaturation: Mild conditions (avoid excessive heating)

  • Reducing conditions are typically required for optimal epitope exposure

• Application-specific considerations:

  Application	Optimal Protocol	Common Pitfalls
  IHC-Paraffin	Citrate buffer antigen retrieval, 1:100-1:500 dilution	Overfixation may mask epitopes
  IHC-Frozen	Light fixation (4% PFA), 1:50-1:200 dilution	Background in highly vascular tissues
  Flow cytometry	Live staining or light fixation, 1:50-1:100 dilution	Harsh fixatives reduce signal
  ICC	4% PFA (10 min), 0.1% Triton X-100, 1:100-1:200 dilution	Excessive permeabilization
  WB	RIPA extraction, reducing conditions, 1:500-1:2000 dilution	Aggregation during sample preparation

Custom optimization may be required for specific tissue types, particularly for tissues with high endogenous peroxidase activity or autofluorescence .

How can I accurately quantify CCR3 expression levels across different experimental systems?

Accurate quantification requires consistent methodology and appropriate reference standards:

• Flow cytometry quantification:

  • Use calibrated fluorescent beads to establish a standard curve

  • Report results as Molecules of Equivalent Soluble Fluorochrome (MESF)

  • Include consistent positive controls across experiments

  • Consider Quantibrite beads for antibody binding capacity determination

• Western blot densitometry:

  • Include a standard curve of recombinant CCR3 protein

  • Normalize to appropriate loading controls (β-actin, GAPDH)

  • Use housekeeping proteins with expression stability in your experimental system

  • Apply digital image analysis with dynamic range verification

• Immunohistochemistry quantification:

  • Develop consistent scoring systems (0-3+ or H-score)

  • Use digital pathology software for objective quantification

  • Include reference slides in each staining batch

  • Report both intensity and percentage of positive cells

• qPCR correlation:

  • Complement protein detection with mRNA quantification

  • Normalize to validated reference genes

  • Be aware that mRNA and protein levels may not directly correlate due to post-transcriptional regulation

• Absolute quantification approaches:

  • Mass spectrometry-based quantification using labeled peptide standards

  • Receptor binding assays with radiolabeled ligands

  • Surface plasmon resonance for binding kinetics assessment

These methodologies enable comparative analysis across experimental conditions while controlling for technical variables.

What strategies can resolve common troubleshooting issues with CCR3 antibodies in experimental settings?

Systematic troubleshooting approaches address common challenges with CCR3 antibody applications:

• High background in immunostaining:

  • Increase blocking stringency (5-10% serum, 1-2 hours)

  • Titrate primary antibody to optimal concentration

  • Include 0.1-0.3% Triton X-100 in wash buffers

  • For tissues with high endogenous peroxidase, use dual blocking (H₂O₂ followed by avidin-biotin)

• Weak or absent signal in Western blotting:

  • Verify protein loading (25-50 μg total protein)

  • Check transfer efficiency with reversible staining

  • Optimize extraction conditions (RIPA buffer with protease inhibitors)

  • Consider membrane pore size (0.2 μm PVDF preferred for smaller proteins)

  • Test longer primary antibody incubation (overnight at 4°C)

• Inconsistent staining patterns:

  • Standardize fixation times and conditions

  • Control temperature throughout protocol

  • Prepare working dilutions fresh for each experiment

  • Consider lot-to-lot antibody variability

• Cross-reactivity issues:

  • Validate with knockout/knockdown controls

  • Perform absorption controls with recombinant protein

  • Test alternative antibody clones targeting different epitopes

  • Consider species homology when working with cross-species samples

• Protocol optimization decision tree:

  Issue	First Approach	If Unsuccessful	Advanced Solution
  No signal	Increase antibody concentration	Enhance detection system	Try alternative epitope antibody
  Nonspecific binding	Increase blocking	More stringent washes	Affinity purify antibody
  Inconsistent results	Standardize sample preparation	Fresh antibody aliquots	Quantitative controls in each experiment
  Wrong molecular weight	Verify sample preparation	Check for post-translational modifications	Confirm with alternative detection method

These strategies have successfully resolved issues in detecting CCR3 across multiple experimental systems, including challenging samples like blood and synovial tissue .

How can CCR3 antibodies be used to explore the relationship between allergic diseases and cancer pathology?

CCR3 functions at the intersection of allergic inflammation and cancer, providing opportunities for mechanistic investigation:

• Tumor microenvironment characterization:

  • Multiplex staining with CCR3 antibodies alongside cancer markers

  • Quantification of CCR3+ immune cell infiltration in different cancer types

  • Correlation of CCR3 expression patterns with tumor progression markers

• Functional studies in cancer models:

  • Blocking CCR3 with neutralizing antibodies in tumor-bearing models

  • Assessing tumor growth kinetics and metastatic potential

  • Investigating changes in tumor-infiltrating immune populations

• Translational research approaches:

  • Analysis of patient tumor samples for CCR3 and CCR3 ligand expression

  • Correlation with clinical outcomes and treatment responses

  • Investigation of CCR3 as a prognostic biomarker in specific cancer types

• Molecular pathway integration:

  • Co-expression analysis of CCR3 with known oncogenic pathways

  • Evaluation of CCR3-mediated signaling effects on cancer cell proliferation

  • Assessment of CCR3 ligand production by tumor cells as a mechanism of immune regulation

CCR3 and its ligands have been implicated in both allergic conditions and cancer progression , suggesting common inflammatory mechanisms that could be targeted therapeutically. The specific role of CCR3+ cells in tumor immunity represents an emerging research frontier with significant translational potential.

What are the latest methodological advances in using CCR3 antibodies for single-cell analysis and spatial biology applications?

Recent technological innovations have expanded the applications of CCR3 antibodies in complex tissue analysis:

• Single-cell protein analysis:

  • Integration with single-cell RNA sequencing through CITE-seq (Cellular Indexing of Transcriptomes and Epitopes by sequencing)

  • Antibody-oligonucleotide conjugates enable protein detection alongside transcriptome analysis

  • Reveals heterogeneity in CCR3 expression at single-cell resolution

• Spatial proteomics approaches:

  • Multiplexed ion beam imaging (MIBI) for high-parameter tissue analysis

  • Imaging mass cytometry for simultaneous detection of 40+ proteins

  • Co-detection by indexing (CODEX) for highly multiplexed tissue imaging

  • Correlation of CCR3 expression with spatial location in tissue architecture

• Live cell imaging applications:

  • Non-blocking fluorescently labeled CCR3 antibodies for dynamic studies

  • Quantum dot conjugation for long-term tracking

  • FRET-based approaches to study receptor-ligand interactions in real-time

• Emerging methodological combinations:

  • Spatial transcriptomics with protein detection

  • Machine learning algorithms for pattern recognition in CCR3+ cell distribution

  • Organ-on-chip models with integrated imaging capabilities

These advanced methodologies are revealing previously unappreciated complexity in CCR3 expression patterns and functional significance across different tissue contexts and disease states.

How can epitope mapping techniques inform the development of more specific and effective CCR3-targeting reagents?

Detailed epitope mapping provides critical insights for next-generation CCR3 research tools:

• Structure-function relationship analysis:

  • Alanine scanning mutagenesis has identified specific amino acids critical for antibody binding (Ala2, Phe3, Asn4, Thr5 for different antibody clones)

  • These findings enable rational design of antibodies targeting functional domains

  • Correlation of epitope location with neutralizing capacity guides therapeutic antibody development

• Cross-species reactivity engineering:

  • Sequence alignment of epitope regions across species

  • Identification of conserved versus variable residues

  • Development of broadly reactive antibodies targeting conserved epitopes

• Application-specific optimization strategies:

  • Non-blocking antibodies for detection without functional interference

  • Conformation-specific antibodies distinguishing active/inactive receptor states

  • Internalization-promoting antibodies for targeted delivery applications

• Advanced epitope-focused engineering approaches:

  Approach	Methodology	Application Advantage
  Phage display optimization	Selection against specific CCR3 domains	Fine epitope specificity
  Synthetic antibody libraries	Structure-guided design	Reduced immunogenicity
  Site-directed mutagenesis	Affinity maturation	Enhanced sensitivity
  Bispecific formats	Dual epitope targeting	Improved specificity or functional modulation

The precise binding characteristics of antibodies like C3Mab-3 and C3Mab-4 to the N-terminal region of CCR3 demonstrate how epitope mapping can inform the development of highly specific research and therapeutic tools with predictable functional properties.

What are the most promising future directions for CCR3 antibody research in both basic science and clinical applications?

The field of CCR3 antibody research is evolving rapidly, with several high-potential research directions:

• Therapeutic applications expansion:

  • Allergic diseases beyond asthma (food allergy, atopic dermatitis)

  • Eosinophilic disorders (eosinophilic esophagitis, hypereosinophilic syndromes)

  • Cancer immunotherapy combinations

  • Neurodegenerative conditions with inflammatory components

• Technical innovations:

  • Antibody engineering for enhanced tissue penetration

  • Bispecific formats targeting CCR3 alongside complementary pathways

  • Antibody-drug conjugates for targeted cell depletion

  • Small format antibody derivatives (nanobodies, affibodies) for improved tissue distribution

• Diagnostic applications:

  • Companion diagnostics for CCR3-targeted therapies

  • Prognostic biomarkers in allergic and inflammatory conditions

  • Imaging applications for visualization of inflammatory foci

• Mechanistic investigations:

  • CCR3 heterogeneity across tissue-specific immune cell populations

  • Receptor signaling dynamics and compartmentalization

  • Differential effects of ligand-specific activation

• Translational research priorities:

  • Biomarker development for patient stratification

  • Combination therapy approaches

  • Tissue-specific targeting strategies

  • Age-dependent and developmental considerations

Continued advancement in antibody technologies combined with deeper understanding of CCR3 biology will likely yield significant innovations in both research tools and therapeutic approaches for allergic and inflammatory diseases .