Anti-Mouse MAdCAM-1 (MECA-89) – Purified in vivo PLATINUM^TM Functional Grade

Clone MECA-89 is used in in vivo mouse studies primarily for targeting MAdCAM-1 (Mucosal Vascular Addressin Cell Adhesion Molecule 1). MAdCAM-1 is a molecule expressed on the surface of endothelial cells in mucosal venules and is involved in homing of lymphocytes to mucosal tissues. The MECA-89 antibody clone is specifically designed to recognize and bind to this molecule.

Use in Research

1. Immune Response Studies: By blocking MAdCAM-1, researchers can study the role of this molecule in immune responses, particularly in the migration of lymphocytes to mucosal tissues.
2. Inflammation and Disease Models: MECA-89 is used to manipulate inflammation and study disease models where MAdCAM-1 plays a critical role, such as in gastrointestinal diseases.
3. Targeting Specific Tissues: The specificity of MECA-89 for MAdCAM-1 makes it useful for delivering therapeutic agents or studying the effects of blocking lymphocyte homing in specific tissues.

Characteristics of MECA-89

• Isotype: Rat IgG2a kappa
• Host: Rat
• Species Reactivity: Mouse
• Purity and Endotoxin Levels: High purity (>95%) and low endotoxin levels (<1.0 EU/mg), making it suitable for in vivo studies where minimizing immune responses to the antibody itself is crucial.

Overall, the MECA-89 clone is a valuable tool for studying the role of MAdCAM-1 in immune responses and disease models in mice.

Recommended Storage Temperature for Sterile Packaged Clone MECA-89

Short-term Storage (?1 month):
Sterile packaged clone MECA-89 antibody (Anti-MAdCAM-1, MECA-89) should be stored at 2–8°C when kept sterile in its original packaging. This temperature range is suitable for maintaining stability for up to one month without significant loss of activity. Always keep the packaging closed and sterile to prevent contamination.

Long-term Storage (>1 month):
For extended storage, aseptically aliquot the antibody into working volumes (without dilution) and freeze at ?–70°C (ideally in a suitable ultra-low freezer). For convenience, –20°C is also acceptable for long-term storage, especially if ultra-low freezers are not available, provided the antibody is protected with glycerol or similar cryoprotectants to prevent repeated freeze-thaw damage—avoiding repeated freeze-thaw cycles is critical for preserving antibody integrity.

Summary Table

Additional Recommendations

• Aseptic Handling: Always aliquot under sterile conditions to prevent contamination.
• Avoid Repeated Freeze-Thaw: Freeze in working volumes to minimize freeze-thaw cycles.
• Manufacturer Guidelines: Always check the specific lot datasheet for any updated storage instructions, as protocols may change.
• Application Note: The optimal working dilution should be determined empirically for each application.

In summary:
Store sterile packaged clone MECA-89 at 2–8°C for short-term use (up to one month). For long-term storage, aliquot and freeze at ?–70°C (or –20°C if necessary), avoiding repeated freeze-thaw cycles. Always handle aseptically and consult the manufacturer’s datasheet for lot-specific guidance.

Based on the available information, MECA-89 is primarily used as an anti-MAdCAM-1 (Mucosal vascular addressin cell adhesion molecule-1) antibody in research applications. While the search results don't provide extensive details about other antibodies commonly used alongside MECA-89, there are several key reagents and controls that are typically employed with this antibody.

Control Antibodies and Reagents

The most commonly mentioned companion reagent is the Purified Rat IgG2a ? Isotype Control (Cat. No. 559073), which serves as the recommended isotype control for MECA-89 in immunohistochemistry applications. This control is essential for validating the specificity of MECA-89 staining and ensuring that observed binding is antigen-specific rather than due to non-specific interactions.

Detection and Amplification Systems

For immunohistochemical applications, MECA-89 is frequently used with a three-step detection system that includes:

• Biotin Goat Anti-Rat Ig (Cat. No. 559286) as the secondary antibody
• Streptavidin-HRP (Cat. No. 550946) for signal amplification
• DAB detection system (Cat. No. 550880) for visualization

Alternative Conjugated Forms

MECA-89 is also available in conjugated formats, including a biotin-conjugated version (Cat. No. 553808) for flow cytometric applications. This provides researchers with flexibility in their experimental design and detection methods.

Application-Specific Considerations

The antibody is routinely tested for flow cytometry applications and has been validated for immunohistochemistry on acetone-fixed frozen sections. It's particularly effective for staining mucosal lymphoid tissue, lamina propria, and splenic sinus lining cells in mouse tissues, making it valuable for studies investigating mucosal immunity and lymphocyte homing mechanisms.

The search results indicate that MECA-89 requires specific tissue preparation methods, as it's not recommended for formalin-fixed paraffin-embedded sections, which may influence the choice of complementary reagents and protocols used in conjunction with this antibody.

Key findings from scientific literature citing clone MECA-89 focus on the mecA gene’s role and clonal dissemination among methicillin-resistant Staphylococcus aureus (MRSA), mapping its genetic context, and its association with antimicrobial resistance.

• Clonal dissemination and lineage tracking: Studies have used both pulsed-field gel electrophoresis (PFGE) and ribotyping to track mecA dissemination across S. aureus lineages globally. Over 60% of mecA+ isolates belong to type I lineages, which include notable pandemic MRSA clones (e.g., Brazilian, North German, Hannover, Iberian, Portuguese). Many mecA^?^ methicillin-susceptible S. aureus (MSSA) clones have mecA^+^ MRSA counterparts that differ by a single PFGE band shift, signifying acquisition of the mecA-containing element, often through SCCmec. This genetic switch has been directly observed and mapped in multiple international outbreaks.

• Genetic structure and resistance determinants: Complete cloning and sequencing of the mecA region revealed that its surrounding genetic cassette (the SCCmec) contains more than 100 open reading frames (ORFs), with several associated with resistance to various antibiotics (including erythromycin, spectinomycin, kanamycin, and bleomycin). The mecA gene encodes PBP2’ and exhibits sequence identity across S. aureus and S. epidermidis, supporting the concept of horizontal gene transfer between staphylococcal species.

• Prevalence in clinical isolates: In clinical staphylococcal isolates (notably, coagulase-negative staphylococci in neonatal septicemia), the mecA gene carriage is high, often likely due to strong antibiotic selection pressures.

In summary, clone MECA-89 citations have advanced the understanding of MRSA’s global spread, the genetic mobility of mecA, and how resistance determinants integrate into widely distributed pandemic clones, shaping public health responses to staphylococcal infections.