Anti-Mouse IFNγ [Clone XMG1.2] — Purified in vivo GOLD™ Functional Grade

The XMG1.2 monoclonal antibody, specific for mouse interferon gamma (IFNγ), is widely used in various in vivo applications in mice. Here are some of its common uses:

1. Neutralization of IFNγ Bioactivity: The XMG1.2 antibody is primarily used to neutralize IFNγ in murine models. This allows researchers to study the role of IFNγ in immune responses, such as in viral or bacterial infections, by inhibiting its activities and observing the effects on immune cell functions.

2. Immunological Research: It is used to dissect the functions of IFNγ in immune responses, including the activation, growth, and differentiation of T and B lymphocytes, macrophages, NK cells, and other cell types.

3. Detection of IFNγ in Tissues and Cells: While not primarily an in vivo application, the antibody's ability to detect intracellular and secreted IFNγ via methods like flow cytometry and ELISA helps in understanding the dynamics of IFNγ production in mouse models.

4. Species-Matched Chimeric Versions for Murine Studies: A recombinant chimeric version of XMG1.2, with a mouse IgG1, κ backbone, is used to minimize immunogenicity and ensure better compatibility in murine models, facilitating studies with reduced risk of anti-drug antibodies.

These applications collectively aid in understanding the complex roles of IFNγ in immune modulation and disease models.

Commonly Used Antibodies and Proteins Paired with XMG1.2

XMG1.2 (clone XMG1.2) is a widely used monoclonal antibody that specifically targets mouse interferon-gamma (IFN-γ). Below are some of the most commonly reported antibodies and proteins used in conjunction with XMG1.2 in the scientific literature.

Antibodies

• Anti-IL-4 (e.g., clone 11B11): Frequently paired with XMG1.2 in multicolor flow cytometry or ELISA panels to profile Th1/Th2 immune responses, as IFN-γ and IL-4 are canonical cytokines secreted by Th1 and Th2 cells, respectively. This combination is essential in differentiating Th1 from Th2 immune polarization.
• Biotinylated R4-6A2: Common as the detection antibody in sandwich ELISA and ELISPOT assays, where XMG1.2 serves as the capture antibody and recombinant mouse IFN-γ as the standard. This pairing allows sensitive quantification of IFN-γ in experimental samples.
• Other Isotype- or Surface Marker-Specific Antibodies: In multiparameter flow cytometry and intracellular cytokine staining (ICS), XMG1.2 (directly fluorochrome-conjugated) is often combined with antibodies against T cell markers (e.g., CD3, CD4, CD8), activation markers (e.g., CD25, CD69), or other cytokines (e.g., IL-2, TNF-α) to phenotype and characterize IFN-γ-producing cells and their activation status.
• Fc Blocking Antibodies and Isotype Controls: To reduce non-specific staining, especially in flow cytometry, XMG1.2 is often used alongside anti-CD16/CD32 (Fc block) and isotype-matched negative control antibodies.

Recombinant Proteins

• Recombinant Mouse IFN-γ: Routinely used as a standard in ELISA, ELISPOT, and neutralization assays, and sometimes as a positive control in functional assays or to calibrate cytokine detection platforms.
• Stimulatory Agents: In functional and ICS assays, XMG1.2 is used in experiments involving stimulation of lymphocytes with mitogens (e.g., phytohemagglutinin), bacterial superantigens (e.g., Staphylococcus enterotoxin B), or cytokines (e.g., IL-2, IL-12) to induce IFN-γ production.

Specialized Applications

• In Vivo Models: For in vivo studies, especially neutralization experiments, XMG1.2 is sometimes used alongside antibodies targeting other cytokines (e.g., anti-TNF, anti-IL-6, anti-IL-10) for combinatorial blockade in immune modulation studies.
• Western Blot and Immunohistochemistry: In these assays, XMG1.2 may be used with general secondary antibodies (e.g., anti-rat HRP for WB, anti-rat fluorescent conjugates for IHC/ICC) to detect IFN-γ in tissue lysates or sections.

Summary Table

Key Points

• XMG1.2 is a cornerstone reagent for detecting and neutralizing mouse IFN-γ in a wide variety of immunological assays.
• Pairing strategies depend on the experimental goal: cytokine profiling (e.g., anti-IL-4), phenotypic analysis (e.g., anti-CD4, anti-CD8), or functional readouts (e.g., recombinant IFN-γ, mitogens).
• In sandwich immunoassays, the combination of XMG1.2 (capture) and biotinylated R4-6A2 (detection) is the gold standard for sensitive, specific quantification of mouse IFN-γ.
• In multiparameter flow cytometry, XMG1.2 is used with antibodies against cell surface markers and other cytokines to dissect complex immune responses.

These combinations are well established in the literature and form the backbone of many experimental protocols in immunology, infection, autoimmunity, and cancer research.

Clone XMG1.2 is a rat monoclonal antibody extensively cited in scientific literature for its specificity and utility in detecting and neutralizing mouse interferon-gamma (IFN-γ), a key cytokine in immune regulation. The most prominent findings from publications using XMG1.2 include:

• Functional Characterization of IFN-γ: XMG1.2 studies have defined IFN-γ as a pleiotropic cytokine crucial for immune regulation, upregulation of MHC class I and II molecules, macrophage activation, antiviral activity, tumor antiproliferative responses, and modulation of various lymphocyte functions.
• Affinity and Fragmentation Advancements: Optimization studies have shown that the F(ab')₂ fragments derived from XMG1.2 can possess even higher affinity for IFN-γ than the intact antibody, potentially due to increased flexibility and effectiveness in bivalent binding. Fine-tuning fragmentation conditions improved yield and efficiency for downstream applications such as ELISA and flow cytometry.
• Detection and Quantification of IFN-γ: XMG1.2 is a gold-standard reagent for flow cytometry and intracellular staining, enabling precise quantification and localization of IFN-γ-producing cells in murine models. The antibody binds specifically to mouse IFN-γ, which is an ~15–20 kDa glycosylated homodimer in its active form.
• Experimental Neutralization and Immunomodulation: In addition to detection, XMG1.2 has been used to neutralize IFN-γ in vivo, allowing researchers to dissect its role in immunity, inflammation, and disease pathogenesis in murine systems.
• Immunology and Disease Models: XMG1.2 has been integral in elucidating IFN-γ’s role in T cell differentiation, dendritic cell function, infectious disease responses (such as viral and tumor models), and autoimmunity.

Collectively, citations of XMG1.2 underpin the antibody’s foundational role in murine immunology, both for diagnostic and functional experiments, and have established IFN-γ as a critical regulator of immune responses and a central target for therapeutic intervention in numerous disease models.

Dosing regimens of the clone XMG1.2 anti-mouse IFNγ monoclonal antibody can vary significantly across different mouse models. These variations are primarily based on the specific experimental design, the type of disease or condition being studied, and the desired therapeutic effect.

1. HLH Model: In studies involving Hemophagocytic Lymphohistiocytosis (HLH) models, the dose of XMG1.2 can range from 8 mg/kg to 100 mg/kg. For example, a dose of 8 mg/kg was used in a model involving perforin-deficient mice infected with mouse cytomegalovirus, although it was noted that this lower dose was not sufficient to alter the disease significantly. Higher doses, typically between 30 mg/kg and 100 mg/kg, are often required to achieve a therapeutic effect in other HLH models.

2. CpG-ODN Induced Hypercytokinemia: In models where CpG-ODN is used to induce hypercytokinemia, administration of XMG1.2 before or after CpG-ODN injection can neutralize IFNγ activity effectively. The efficacy of IFNγ neutralization can depend on the timing and dose of XMG1.2 administration.

3. General Application: In general, dosing schedules for XMG1.2 can be designed based on the specific goals of the study, such as enhancing or inhibiting immune responses. For instance, in some studies, XMG1.2 is administered intraperitoneally (i.p.) in doses that can significantly impact the immune system's activity.

These variations highlight the importance of optimizing the dosing regimen for each specific experimental model to achieve the desired effects.