Product Information

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Product Background

G-protein coupled receptor 87 (GPR87) is an orphan G protein-coupled receptor implicated in cell proliferation, survival signaling, tumor progression, epithelial biology, and stress-response pathways. GPR87 has attracted increasing research interest due to its association with multiple cancer types and its potential role in p53-regulated signaling networks.

GPR87 is widely studied in cancer biology, GPCR signaling, epithelial cell biology, drug discovery, and receptor-mediated signaling research.

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Antibody Development

HM0059 was generated by phage-display selection using a mouse-derived antibody library. Recombinant epitope-Fc fusion protein containing the GPR87 epitope sequence was used as the selection antigen. Following identification of the initial antibody candidate, structure-guided affinity optimization was performed to improve binding affinity and specificity.

The optimized antibody was reconstructed as a full-length mouse IgG1 recombinant antibody and expressed in HEK293 cells.

Binding and specificity were evaluated by:

• ELISA using recombinant epitope-Fc fusion antigen
• Western blot detection of endogenous full-length GPR87 protein

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Validation Data

ELISA Validation

ELISA demonstrated specific binding to recombinant epitope-Fc fusion antigen, while minimal binding was observed against Fc-only control protein.

Validation conditions:

• Well 1: Fc control protein
• Well 2: Epitope-Fc fusion protein
• Detection substrate: TMB

Note:
ELISA validation confirms binding to epitope-Fc fusion antigen. Full-length protein binding in solution has not been tested by ELISA.

 

Western Blot Validation – Recombinant Fusion Protein

Western blot analysis demonstrated specific recognition of recombinant MBP-epitope fusion protein expressed in BL21(DE3) cells, while no significant binding was observed against MBP control protein.

Validation conditions:

• Lane 1: MBP control protein
• Lane 2: MBP-epitope fusion protein
• Standard reducing Western blot

Western Blot Validation – Endogenous Full-Length Protein

Endogenous human GPR87 protein was detected in human cell lysates under reducing Western blot conditions.

Validated samples:

• 293T cells
• HeLa cells
• HepG2 cells

Observed bands:

• Major immunoreactive bands were detected around approximately 30–35 kDa.
• Additional higher molecular weight bands around approximately 70 kDa were also observed in liver and intestine samples, potentially representing glycosylated forms, receptor-associated complexes, or oligomeric species.

Detection condition:

• Standard reducing Western blot
• HRP-conjugated anti-mouse secondary antibody