Anti-Mouse CD70 (Clone FR70) – Purified in vivo GOLD™ Functional Grade

Clone FR70, a rat monoclonal antibody targeting mouse CD70, is widely utilized in various in vivo applications in mouse models. This antibody has proven particularly valuable for studying immune responses, transplantation, and cancer biology through its ability to interfere with CD70-CD27 interactions.

Blocking CD70-CD27 Interactions

The primary in vivo function of FR70 involves blocking the interaction between CD70 and its ligand CD27. This blockade is critical for investigating the role of CD70-CD27 signaling in immune regulation, as this pathway is important in T-B cell crosstalk and plays a significant role in costimulation and immune regulation. The FR70 antibody efficiently interferes with mouse CD70 functions, making it particularly useful for mechanistic studies.

Immunology and Transplantation Studies

FR70 is primarily used in vivo to study immunological processes and transplantation tolerance in mouse models. Since CD70 is transiently expressed on antigen-activated B and T cells, natural killer cells, and mature dendritic cells, blocking its function with FR70 allows researchers to examine the consequences of disrupting this activation pathway. The antibody's ability to inhibit T cell and NK cell functions makes it valuable for understanding immune cell interactions during transplant rejection or tolerance induction.

Cancer Immunotherapy Research

Another significant in vivo application involves cancer immunotherapy studies. This application is particularly relevant because CD70 is aberrantly expressed on malignant cancer cells, making it an attractive target for therapeutic intervention. Researchers use FR70 to investigate how blocking CD70 affects tumor growth, immune surveillance, and the tumor microenvironment in mouse cancer models.

Technical Considerations for In Vivo Use

For in vivo applications, FR70 is manufactured with low endotoxin levels (< 1.0 EU/mg) and high purity (≥95% monomer). The antibody is formulated in phosphate buffered saline without carrier proteins or preservatives, making it suitable for systemic administration in mice. These quality specifications are essential for minimizing non-specific inflammatory responses that could confound experimental results in living animals.

The most commonly used antibodies or proteins alongside FR70 (an anti-mouse CD70 antibody) in the literature are those that characterize immune cell subpopulations and functional states, particularly in studies of immune activation or tolerance.

Key antibodies and proteins used with FR70 include:

• CD4 and CD8: To identify and quantitate helper and cytotoxic T cell subsets by flow cytometry or immunostaining.
• CD11c and CD11b: Markers for dendritic cells; often used together to define CD11c^+^CD11b^+^ dendritic cell populations.
• Co-stimulatory molecules:
  • CD40
  • CD80
  • CD86
    These are assessed mainly on dendritic cells to evaluate their activation status or antigen-presenting capability in the context of FR70 treatment.
• Major Histocompatibility Complex (MHC) class II: Used to assess antigen presentation ability of dendritic cells or other antigen-presenting cells.
• PD-L1 (Programmed death-ligand 1): Its expression is also quantified, as FR70 can modulate its levels on dendritic cells.
• Isotype controls: Such as rat IgG2b, to ensure specificity of FR70 binding in experiments.

Other combinations exist depending on study context:

• CD25 and CD8: In combination therapies studying immune regulation or depletion of certain lymphocyte subsets.
• BrdU: Used for co-staining to detect proliferating cells in tissue sections.

Summary Table

These combinations allow for robust immunophenotyping, functional immune assays, and mechanistic studies on the effects of FR70 on immune system modulation within various experimental frameworks.

Clone FR70, an anti-mouse CD70 antibody, has been extensively studied in scientific literature for its role in modulating immune responses. Here are the key findings from its citations:

Key Findings

1. Role in Immune Modulation and Tolerance:

   • FR70 is used to block the interaction between CD70 and its receptor CD27, which plays a crucial role in T-B cell cross-talk and costimulation of immune responses.
   • It promotes long-term graft acceptance by reducing cytotoxic T lymphocyte (CTL) proliferation and inducing tolerogenic dendritic cells and regulatory T cells.

2. Impact on T Cell Activities:

   • FR70 inhibits the costimulatory activity of CD70 on T cell proliferation, which is critical for T-dependent immune responses.
   • It reduces the expression of CTL-related genes in certain contexts, contributing to immune suppression.

3. Utility in Cancer and Immunotherapy:

   • CD70 is overexpressed on malignant cells, making it a potential target for cancer immunotherapy.
   • Anti-CD70 antibodies like FR70 may help in developing strategies to target CD70 for therapeutic purposes.

4. Applications in Research:

   • FR70 is used in flow cytometric analysis to study CD70 expression on activated T and B lymphocytes.
   • It is effective in blocking CD70 in vitro, which can be useful for studying CD70's functions and interactions.

Dosing regimens for clone FR70, an anti-mouse CD70 monoclonal antibody, differ significantly depending on the mouse model, disease context, and experimental objectives.

Key dosing regimen variations across different contexts include:

• Transplantation Models: In a heterotopic cardiac transplantation mouse model, FR70 was used as a monotherapy to induce long-term allograft acceptance. In this study, the specific dose, frequency, and route of FR70 administration were not detailed in the available summary, but standard practice for in vivo monoclonal antibody dosing in such models is typically 10–500 μg per injection, administered via intraperitoneal (i.p.) or intravenous (i.v.) routes, with dosing intervals ranging from once at transplantation to multiple doses over days to weeks. The cited study used FR70 to achieve graft survival well beyond controls (mean ~100 days vs. ~8 days for control).

• Autoimmunity Models: In experimental autoimmune encephalomyelitis (EAE), in vivo administration of anti-mouse CD70 mAb (clone FR-70) showed efficacy in suppressing disease onset. Details in the patent literature similarly support dosing ranges within the typical in vivo antibody dose window for mice (100–500 μg/dose i.p. or i.v., given 1–3 times/week), but study-specific protocols may vary.

• Flow Cytometry and In Vitro Applications:

  • For flow cytometry (FC): The recommended working concentration is ≤0.25 μg per 1 million cells in 100 μl.
  • For western blot (WB): Recommended concentration is 1–10 μg/ml.
  • Each investigator should titrate for optimal performance based on application.

• General Recommendations: Suppliers recommend investigators adjust dosing regimens according to the specific experimental design, mouse strain, and disease context. Detailed optimal dosing for FR70—such as frequency, total duration, and timing relative to disease induction—should be determined case by case and can often be derived from published literature for the disease model being used.

When designing experiments:

• Transplantation and autoimmunity models tend to use higher antibody doses and multiple injections to achieve immunomodulation.
• Tumor or infection models may use dosing adjusted for tumor burden or immune activation state.
• In all applications, efficacy and potential toxicity should be monitored, and pilot titration studies are recommended.

Summary Table: FR70 Dosing in Mouse Models

Investigators should consult recent literature and suppliers' datasheets for model-specific details, as protocols can be updated and may be tailored for new indications or genetic backgrounds.