LCR27 Antibody
Description
CD27 Antibodies in Immunotherapy
CD27 is a tumor necrosis factor (TNF) receptor superfamily member critical for lymphocyte activation. Key antibodies targeting CD27 include:
Varlilumab (CDX-1127)
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Mechanism: Agonistic monoclonal antibody (IgG1) that activates CD27 signaling to enhance T-cell-mediated antitumor responses .
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Clinical Applications:
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Preclinical Data: Synergizes with PD-1/PD-L1 inhibitors to eradicate tumors in murine models .
LG.7F9 Antibody
SC27 Antibody for Broad-Spectrum COVID-19 Neutralization
A groundbreaking anti-SARS-CoV-2 antibody developed by UT Austin and Texas Biomed:
Key Features of SC27
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Target: Binds conserved regions of the spike protein, including:
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Neutralization Breadth:
Virus Tested Neutralization Efficacy SARS-CoV-2 (XBB.1.5, BA.2) 100% (in vitro) SARS-CoV-1 98% Bat-CoV RaTG13 95% -
In Vivo Efficacy: 100% survival in murine models challenged with Omicron BA.5 .
CCL27/CTACK Antibody (AF725)
Although not named "LCR27," this chemokine-targeting antibody has dermatological relevance:
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Target: Mouse CCL27 (cutaneous T-cell-attracting chemokine).
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Applications:
Emerging Trends in Antibody Engineering
Product Specs
Constituents: 50% Glycerol, 0.01M Phosphate Buffered Saline (PBS), pH 7.4
Target Background
Q&A
What structural features enable SC27 to neutralize diverse SARS-CoV-2 variants?
SC27 targets two conserved epitopes on the spike protein:
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ACE2-binding site blockade: Prevents viral entry by steric hindrance .
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Cryptic-site binding: Recognizes a conserved region beneath the spike’s receptor-binding domain (RBD), which shows minimal mutational escape .
Methodological Insight:
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Epitope mapping was performed using cryo-EM and competitive binding assays with ACE2 and RBD-directed antibodies .
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Neutralization assays against 12 coronaviruses (including SARS-CoV-1, pangolin/bat CoVs) confirmed cross-reactivity .
How are CD27 antibodies validated for specificity in flow cytometry?
CD27 antibodies (e.g., clones LG.7F9, O323) require:
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Cross-reactivity testing: Confirmed in human, mouse, and rat cells using knockout models .
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Functional validation: Blocking CD27-CD70 interactions in vitro (e.g., reduced T-cell proliferation in EBV models) .
Data Contradiction Analysis:
Recommendation: Use humanized mouse models or nonhuman primates to better mimic human immune responses .
What methodologies identify class 1/4 antibodies like SC27 post-vaccination?
SC27 was isolated via:
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Single-cell sorting: Antigen-specific B cells from vaccinated donors .
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Next-gen sequencing: VH/VL gene amplification and recombinant expression in HEK293 cells .
Key Steps:
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PBMC sampling: 7–10 days post-booster vaccination for peak ASC (antibody-secreting cell) activity .
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High-throughput screening: Multiplexed ELISA against spike proteins of 12 variants .
Why does CD27 blockade impair BMLF1-specific CD8+ T cells but not LMP2-specific responses?
Mechanistic Insight:
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BMLF1-specific cells rely on CD27 costimulation for clonal expansion and cytotoxicity .
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LMP2-specific cells utilize alternative pathways (e.g., CD28 or 4-1BB) .
Experimental Validation:
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CD27 knockout mice: Uncontrolled EBV replication and reduced BMLF1-specific T-cell proliferation .
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Cytotoxicity assays: CD27-blocked T cells showed 60% reduced killing of EBV-transformed B cells (p < 0.01) .
Key Data Table: SC27 vs. Other Monoclonal Antibodies
Methodological Recommendations for Antibody Research
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For epitope discovery: Combine hydrogen-deuterium exchange mass spectrometry (HDX-MS) with alanine scanning mutagenesis .
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For in vivo testing: Use BLT mice (bone marrow-liver-thymus humanized) to model human immune responses .
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For high-resolution structural data: Prioritize cryo-EM over X-ray crystallography for flexible viral proteins .
