Anti-Mouse CD62L [Clone MEL-14] — Purified in vivo GOLD™ Functional Grade

In Vivo Use of Clone MEL-14 in Mouse Studies

The MEL-14 monoclonal antibody is specific for mouse CD62L (L-selectin), a critical adhesion molecule expressed on leukocytes, including most T and B lymphocytes, neutrophils, monocytes, and eosinophils. Its primary in vivo application is to block the function of L-selectin for experimental purposes.

Mechanism in Vivo

Lymphocyte Homing Inhibition:
Pre-incubation of lymphocytes with MEL-14 has been shown to completely and specifically block the binding of lymphocytes to high endothelial venules (HEV) in vitro and, critically, to inhibit the migration of lymphocytes into lymph nodes in vivo. This effect is due to MEL-14’s ability to interfere with L-selectin’s interaction with its ligands on HEVs, which is essential for the homing of naïve lymphocytes to peripheral lymph nodes.

Functional Blockade:
In practical terms, MEL-14 is used to transiently inhibit L-selectin-mediated adhesion in vivo, allowing researchers to study the role of this molecule in immune cell trafficking, inflammation, and immune responses. This has been instrumental in elucidating the mechanisms of lymphocyte recirculation and the extravasation of leukocytes into tissues.

Technical Details

• Administration: MEL-14 can be administered to mice intravenously or intraperitoneally, depending on the experimental design.
• Dosage and Timing: The optimal dose and timing depend on the specific experimental question, but the antibody is typically given prior to the induction of inflammation or immune challenge to ensure L-selectin blockade during the critical window of cell trafficking.
• Controls: Appropriate controls (e.g., isotype-matched antibodies) are essential to distinguish specific effects of L-selectin blockade from non-specific antibody effects.

Applications in Research

• Study of Lymphocyte Trafficking: MEL-14 is a key tool for investigating the mechanisms of lymphocyte homing to lymphoid organs.
• Inflammation Models: By blocking L-selectin, researchers can assess the contribution of this molecule to leukocyte recruitment in models of inflammation or infection.
• Distinguishing T Cell Subsets: Although primarily an in vivo blocking reagent, MEL-14 is also used in flow cytometry to distinguish naïve, effector, and memory T cell subsets based on CD62L expression.

Limitations

• Transient Effect: MEL-14 provides a transient blockade, not a genetic knockout, so effects are limited to the duration of antibody presence.
• Specificity: The blockade is specific to L-selectin and does not affect other selectins (E- or P-selectin).

Summary Table

In summary, clone MEL-14 is primarily used in vivo in mouse studies to block L-selectin (CD62L) function, thereby inhibiting lymphocyte homing to lymph nodes and modulating leukocyte recruitment in inflammation. This allows researchers to dissect the specific roles of L-selectin in immune responses and leukocyte trafficking.

The correct storage temperature for sterile packaged clone MEL-14 (anti-mouse CD62L antibody) is between 2°C and 8°C, and it should be protected from prolonged exposure to light and not frozen. Store the solution undiluted within this temperature range.

These instructions are consistent across major antibody suppliers and specifically apply to the MEL-14 clone used for flow cytometry and related immunological assays.

• Do not freeze the antibody, as this could compromise its integrity.
• Protection from light is important to prevent degradation of conjugated antibodies (such as those labeled with fluorescent dyes).
• Storage outside the 2°C-8°C range may decrease shelf life and efficacy.

General guidelines for sterile packaging also emphasize the importance of keeping sterile items stored in a clean, enclosed environment to avoid exposure to contaminants, moisture, or temperature extremes.

MEL-14 is a monoclonal antibody used to detect mouse CD62L (L-selectin), a key lymphocyte homing receptor. In the literature, MEL-14 is most commonly used in combination with antibodies or proteins that mark lymphocyte subsets or related adhesion and activation molecules to analyze trafficking, homing, and functional phenotypes.

The most common additional antibodies or proteins used alongside MEL-14 include:

• CD3: Pan-T cell marker.
• CD4 and CD8: To distinguish T cell subsets (helper and cytotoxic T cells).
• CD44: To assess lymphocyte activation and memory status, often in tandem with CD62L to define naive (CD62L^high CD44^low), central memory (CD62L^high CD44^high), and effector memory (CD62L^low CD44^high) T cells.
• CD19 or B220: B cell markers.
• CD45RB, CD45RA, CD45RO: To examine leukocyte differentiation and maturation.
• CD25: IL-2 receptor alpha, for activated/regulatory T cells.
• CD69, CD11a, CD11b: Other activation or adhesion molecules that may be analyzed together with CD62L.
• Chemokine receptors (e.g., CCR7, CXCR5) and selectins/adhesion molecules like CD62P (P-selectin) and CD62E (E-selectin) for studies of cell migration, homing, and tissue localization.

In functional or immunophenotyping panels, these markers are often selected to dissect the functional states and trafficking potentials of lymphocytes. The combination of CD44 and CD62L (MEL-14) is especially well established for T cell memory/naive profiling.

Supporting context:

• MEL-14 is widely used in flow cytometry panels, immunohistochemistry, and in blocking or functional experiments to investigate lymphocyte extravasation and migration.
• Several commercial and methodological documents confirm these combinations, with major vendors and literature recommending and validating such panels.

These combinations allow researchers to identify the phenotypes and migration capabilities of various lymphocyte populations in both steady-state and experimental conditions.

The key findings from scientific literature citing clone MEL-14 center on its role as a monoclonal antibody that specifically recognizes the mouse homing receptor CD62L (L-selectin), which is crucial for lymphocyte migration and adhesion to peripheral lymph node high endothelial venules.

• Epitope Recognition: MEL-14 binds to the lectin domain of mouse CD62L (peripheral lymph node homing receptor). It recognizes a determinant within the N-terminal 53 amino acids of the lectin domain, and its epitope's conformation may depend on the presence of the EGF domain.

• Functional Blocking: MEL-14 efficiently blocks lymphocyte binding to peripheral lymph node endothelium both in vitro and in vivo, implicating the lectin domain in the adhesive interaction central to lymphocyte homing.

• Tool for Experimental Immunology: Blocking CD62L with MEL-14 monoclonal antibody prevents lymphocyte migration into lymph nodes, and has been used to disrupt lymphadenopathy in mouse models. This demonstrates its value in studying lymphocyte trafficking, immune response modulation, and lymphoid tissue architecture.

• Biological Insights: Research using MEL-14 has helped clarify that CD62L's lectin domain interacts with a carbohydrate ligand on high endothelial venules, thus validating the mechanism of lymphocyte homing to lymph nodes.

• Commercial and Diagnostic Utility: MEL-14 clone is a standard reagent for detecting mouse CD62L in flow cytometry, immunohistochemistry, and functional assays, making it widely used for mouse immunology investigations.

In summary, clone MEL-14 is foundational in delineating the molecular and functional properties of mouse CD62L, especially its lectin domain, and remains a vital tool for immunological research on lymphocyte trafficking and immune system regulation.