Calreticulin Antibody

Overview

Calreticulin Antibody is a research-use antibody directed against CALRETICULIN. It is supplied for use in common immunoassay contexts such as WB, IHC-P, FACS, Direct ELISA (RUO).

Key elements and design rationale

• Target: CALRETICULIN.
• Description (provided): Calreticulin, also known as calregulin, CRP55, CaBP3, calsequestrin-like protein, and endoplasmic reticulum resident protein 60 (ERp60) is a protein that in humans is encoded by the CALR gene.
• Antibody type: Rabbit, Polyclonal (rabbit origin), Rabbit IgG.
• Format: Antigen affinity purified; Affinity purified.
• Reported/predicted localization: Cytoplasmic.
• Species reactivity: tested: Human, Mouse, Rat.
• Immunogen (if provided): A human recombinant protein (amino acids E18-S323) was used as the immunogen for the Calreticulin antibody..

The information above helps you match the antibody format to your assay context, interpret species-dependent differences, and anticipate how epitope context (isoforms, PTMs, or conformational state) may influence signal.

Biological background

Calreticulin, also known as calregulin, CRP55, CaBP3, calsequestrin-like protein, and endoplasmic reticulum resident protein 60 (ERp60) is a protein that in humans is encoded by the CALR gene. It is mapped to 19p13.13. Calreticulin is a multifunctional protein that acts as a major Ca(2+)-binding (storage) protein in the lumen of the endoplasmic reticulum. It is also found in the nucleus, suggesting that it may have a role in transcription regulation. Calreticulin binds to the synthetic peptide KLGFFKR, which is almost identical to an amino acid sequence in the DNA-binding domain of the superfamily of nuclear receptors. Calreticulin binds to antibodies in certain sera of systemic lupus and Sjogren patients which contain anti-Ro/SSA antibodies, it is highly conserved among species, and it is located in the endoplasmic and sarcoplasmic reticulum where it may bind calcium. The amino terminus of calreticulin interacts with the DNA-binding domain of the glucocorticoid receptor and prevents the receptor from binding to its specific glucocorticoid response element. Calreticulin can inhibit the binding of androgen receptor to its hormone-responsive DNA element and can inhibit androgen receptor and retinoic acid receptor transcriptional activities in vivo, as well as retinoic acid-induced neuronal differentiation. Thus, calreticulin can act as an important modulator of the regulation of gene transcription by nuclear hormone receptors. Systemic lupus erythematosus is associated with increased autoantibody titers against calreticulin but calreticulin is not a Ro/SS-A antigen. Earlier papers referred to calreticulin as an Ro/SS-A antigen but this was later disproven. Increased autoantibody titer against human calreticulin is found in infants with complete congenital heart block of both the IgG and IgM classes.

For curated annotations (gene/protein naming, domains, isoforms, and pathway links) for CALRETICULIN, consult primary databases such as UniProt, NCBI Gene, and Ensembl.

Research relevance and current trends

• Context-dependent expression studies: researchers often examine CALRETICULIN abundance and localization across perturbations (genetic, pharmacologic, or environmental) to connect phenotype to molecular changes.
• Reagent reproducibility: there is growing emphasis on antibody specificity checks using orthogonal approaches (e.g., genetic perturbation or independent antibodies) and transparent reporting of clone/lot information.
• Multi-modal datasets: antibody-based readouts are increasingly combined with transcriptomics and imaging to relate protein-level measurements to cell-state transitions.

Common research applications

• Western blotting (immunoblot) for relative detection of target protein abundance and apparent molecular weight.
• Immunohistochemistry for spatial mapping of target expression across tissues and cell types.
• FACS: commonly used to detect or compare CALRETICULIN across experimental conditions (conceptual guidance only).
• Direct ELISA: commonly used to detect or compare CALRETICULIN across experimental conditions (conceptual guidance only).

When comparing conditions, interpret changes in signal in the context of sample composition, expected localization, and any known isoform complexity for the target.

Notes for experimental interpretation

• Isoforms and PTMs: alternative splicing or post-translational modifications can change epitope accessibility and apparent molecular weight; interpret bands/signals accordingly.
• Cross-reactivity and matrix effects: background binding can vary by sample type, species, and blocking/detection chemistries; include appropriate negative controls.
• Control concepts: where feasible, use genetic perturbation (KO/KD/overexpression), orthogonal assays, or independent antibodies to support specificity claims.

Antibody considerations: Polyclonal reagents may recognize multiple epitopes and can increase sensitivity but may show broader binding profiles, while monoclonal clones provide a single-epitope readout that can improve consistency across experiments. If a conjugate is listed, the antibody supports more direct detection workflows; otherwise, it is typically used with a compatible secondary antibody.

Customization & Add-ons: Can’t find the antibody you need—or require a custom format for your assay? We can help you source the best match or support custom antibody solutions for diverse research needs, including species and isotype selection, conjugations and labeling (e.g., HRP/AP, biotin, fluorophores), purification grade options (Protein A/G, affinity purified), formulation preferences (buffer selection, carrier-free, glycerol-free), custom concentrations and aliquoting, low-endotoxin options for cell-based work, and application-focused QC/validation support (project dependent). Click Talk to a Scientist to submit a request, email us at support@biohippo.com, or explore our Research Services for additional support—our team will follow up with feasibility details and next steps.