Anti-Mouse CD22 (Clone MB22-11) – Purified in vivo PLATINUM™ Functional Grade

The clone MB22-11, which is a mouse anti-mouse CD22 monoclonal antibody, is commonly used in in vivo applications involving mice for several purposes:

1. B Cell Depletion: MB22-11 is used to deplete B cells in mice, effectively reducing B cell numbers. This is especially useful in studies focused on autoimmune diseases and B cell biology.

2. Functional Analysis: The antibody is utilized in functional studies to investigate B cell functions and mechanisms in diseases. It helps in understanding how CD22 plays a role in B cell behavior and interactions.

3. ELISA and Other Applications: Beyond B cell depletion, MB22-11 is also applied in Enzyme-Linked Immunosorbent Assay (ELISA) for detecting CD22 and in other applications such as neutralization/blocking assays.

4. Blocking CD22 Ligand: MB22-11 can inhibit CD22-mediated adhesion, which is crucial for understanding B cell interactions and adhesion processes.

These applications highlight the versatility of the MB22-11 clone in mouse models for immunological and pathological research.

The most commonly used antibodies and proteins associated with MB22-11 (anti-mouse CD22) in the literature include:

• Anti-mouse CD20 (e.g., MB20-11): Frequently paired for comparative studies on B cell depletion mechanisms and efficiency.
• Isotype controls: Such as IgG2a, IgG2c, and IgG1, which serve as negative controls to validate specificity in experiments.
• Biotinylated secondary antibodies: Used for detection purposes in flow cytometry and ELISA.
• CD22-Fc fusion proteins: Applied in binding and inhibition assays to elucidate the interactions and blocking capabilities of MB22-11.
• Signaling proteins—SHP-1, Syk, Lck, Lyn: Utilized in pathway analysis to study the mechanistic impact of CD22 targeting on intracellular B cell signaling.
• Non-blocking monoclonal antibodies: Sometimes used as additional controls to further specify the effects unique to MB22-11.

MB22-11 is primarily a tool in murine immunology, focusing on B cell biology, depletion strategies, and signaling mechanisms. Its combination with the above antibodies or proteins is fundamental for validating experimental findings, dissecting molecular pathways, and ensuring assay specificity.

Key findings from scientific literature on clone MB22-11 (anti-mouse CD22 mAb) center on its ability to efficiently deplete specific B cell populations in mice, elucidate CD22’s biological role, and its distinct mechanism of action compared to anti-CD20 antibodies.

Essential findings:

• B cell depletion: MB22-11 rapidly depletes mature, recirculating B cells in the bone marrow, blood, and marginal zone, but has limited impact (~20% depletion) on mature follicular B cells in C57BL/6 mice.
• Mechanism: Depletion occurs through antibody-dependent cellular cytotoxicity (ADCC)-independent mechanisms; MB22-11 works primarily by interfering with CD22’s ligand binding, a critical survival factor for peripheral B cells.
• Efficacy across mouse strains: Responds similarly in wild-type (C57BL/6) and autoimmune-prone (NZB/W F1) mice under standard dosing regimens, with robust depletion of marginal zone and recirculating B cells in both strains.
• Effect on B cell subpopulations: MB22-11 is highly effective against most mature B lineage cells but is less effective for follicular B cells.
• Biological implications: Use of MB22-11 increases B cell turnover in blood, lymph nodes, and spleen, and reduces surface CD22 to nearly undetectable levels in vivo.
• In vitro activity: Blocks >90% of CD22-mediated adhesion and completely inhibits CD22-Fc binding to lymphocytes.
• Dosing regimens: Typically administered at 100 μg per mouse for strong depletion (alternative protocols may use lower doses for long-term studies), with similar efficacy regardless of strain; regimen is tailored to experimental needs rather than strain-specific factors.

Comparison to anti-CD20 antibodies:

• Both CD20 and CD22 mAbs deplete B cells, but they differ in targeted subpopulations and mechanisms: CD20 mAbs generally produce broader depletion across B cell types, while MB22-11 targets specific subsets with a unique mechanism.

These findings establish MB22-11 as a valuable experimental tool for dissecting B cell biology, the function of CD22, and related immune processes in murine models.

Dosing Regimens of Clone MB22-11 in Mouse Models

Clone MB22-11 (anti-mouse CD22) is widely used to study B cell biology, depletion, and signaling in vivo, but detailed information on dosing regimens across different mouse models is limited in the literature. Here’s what can be summarized from the available evidence:

General Dosing Consistency

Dosing regimens of MB22-11 are generally consistent across various mouse models, such as NZB/W F1 and C57BL/6, with adjustments primarily based on experimental objectives and desired duration of B cell depletion rather than differences in mouse strain. This suggests that strain-specific pharmacokinetics or pharmacodynamics do not play a major role in altering the effective dose.

Example Dose and Efficacy

A single dose of MB22-11 (100 μg) has been shown to deplete mature recirculating bone marrow, blood, and marginal zone B cells comparably in both NZB/W F1 and C57BL/6 mice. Specifically, depletion rates for these B cell subsets were similar between the two models, indicating that the same dose can be effective in different genetic backgrounds.

Experimental Factors Influencing Dosing

While there is no evidence of intrinsic model-based differences in MB22-11-induced B cell depletion, dosing may still vary depending on:

• Experimental goals: Prolonged or repeated dosing may be used to achieve sustained B cell depletion, while single doses may suffice for acute studies.
• Desired depletion duration: The extent and persistence of B cell depletion may guide whether a single dose or a multi-dose regimen is employed.
• Endpoint measurements: The parameters being measured (e.g., peripheral blood vs. bone marrow B cells) could influence dosing frequency and timing.

Key Points

• Dose: 100 μg of MB22-11 is an effective single dose for acute B cell depletion in both NZB/W F1 and C57BL/6 mice.
• Route: The standard route of administration for similar in vivo antibodies is typically intraperitoneal, but this is not explicitly documented for MB22-11 in the provided literature.
• Dosing Schedule: While repeated dosing intervals (e.g., weekly or biweekly) could be considered for longer-term studies, the primary literature does not detail multi-dose regimens for MB22-11.
• Strain Differences: No significant strain-specific differences in dose response have been reported; dosing is more likely to be adjusted based on experimental design rather than mouse model.

Summary Table

Conclusion

Dosing of clone MB22-11 is generally consistent across mouse models, with a standard single dose (e.g., 100 μg) producing comparable B cell depletion in different strains. Adjustments to the regimen are driven by experimental needs rather than intrinsic differences between mouse models. Researchers should confirm dosing in the context of their specific experimental endpoints and consider pilot studies if prolonged or repeated depletion is desired.