LAG3 Antibody / Lymphocyte activation gene 3 / CD223

Overview

LAG-3 (also called CD223) is a high affinity MHC class II ligand present on the surface of CD4+CD8+ T cells and NK cell, with shared homology in structure to CD4 molecules. It has a glutamic acid-proline (EP) repetitive sequence found in other functionally distinct mammalian, parasitic, and bacterial proteins that may influence a conserved biological function. LAG-3+CD4+CD8+ T cells can associate with the T cell receptor (TCR) and downregulate TCR signaling in vitro. LAG-3 inhibits CD4-dependent T cell function via its cytoplasmic domain. LAG-3 Lys-468 within a conserved 'KIEELE' motif is essential for interaction with downstream signaling molecules. Furthermore, as a checkpoint inhibitor target, it may be superior to CTLA-4 and PD-1 since both antibodies only activate effector T-cells, whereas an antagonist LAG-3 antibody can both activate T effector cells (by downregulating the LAG-3 inhibiting signal into pre-activated LAG-3+ cells) and inhibit induced (i.e. antigen-specific) Treg suppressive activity.

This anti-LAG3 antibody is supplied as Purified (Mouse, Monoclonal (mouse origin), clone LAG3/3261, Mouse IgG2a, kappa, Unconjugated) and is designed to support common target-detection workflows after the on-page specifications.

Key elements and design rationale

• Target: LAG3
• Format: Purified
• Species reactivity: Human
• Applications (listed): ELISA
• Conjugate: Unconjugated
• Clone and antibody class: Monoclonal (mouse origin), clone LAG3/3261, Mouse IgG2a, kappa

Because antibody performance can depend on epitope context, sample preparation, and biological state, interpret signals using appropriate controls and orthogonal evidence when possible.

Biological background

LAG3 is referenced in public gene/protein resources (e.g., UniProt and NCBI Gene), which provide curated names/synonyms, protein features, and pathway context. When designing assays, consider potential isoforms, post-translational modifications, and cell-type specific expression that may influence observed signal.

Research relevance and current trends

• Profiling LAG3 expression across model systems, perturbations, and time points to support mechanistic hypotheses.
• Combining antibody-based detection with multi-omics or imaging readouts to link LAG3 signal with phenotype.
• Using well-matched controls (isotype controls, genetic perturbations, or independent reagents) to strengthen interpretation of target-associated signal.

Common research applications

• ELISA

Use the listed applications as a starting point and tailor experimental design to your sample type and readout requirements.

Notes for experimental interpretation

• Specificity considerations: closely related family members, isoforms, or PTMs can affect apparent specificity; confirm with independent approaches when critical.
• Controls: include negative controls and, when feasible, genetic or pharmacologic perturbations to support target attribution in your system.
• Species and sample context: differences in sequence, expression, fixation, or extraction conditions can change signal behavior across models.

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.