Anti-Mouse CD3ε [Clone 145-2C11] F(ab’)2 fragment — Purified in vivo GOLD™ Functional Grade

Clone 145-2C11 is most commonly used in vivo in mice for T cell depletion, activation, and functional modulation across a variety of immunological and disease models.

Key in vivo applications include:

• T cell depletion: 145-2C11 can induce robust depletion of the T cell population, making it a standard tool for studies requiring transient or sustained loss of T cells to dissect immune mechanisms.
• T cell activation: Administration of 145-2C11 in vivo stimulates T cell receptor (TCR)/CD3 complex signaling, resulting in widespread T cell activation and proliferation. This is widely employed in models exploring cytokine storm, T cell-mediated pathology, and regulatory mechanisms within the immune system.
• Functional modulation: 145-2C11 is used to modulate T cell functions in vivo, such as altering cytokine production, effector responses, or immune tolerance. These effects are relevant in transplantation, autoimmunity, and infection models.
• Cytometry detection: Injection of 145-2C11 enables enumeration and tracking of T cell populations using flow cytometry and immunofluorescence.
• Disease modeling: The antibody is used in mouse studies to manipulate T cell dynamics in oncology, autoimmunity, transplant rejection, and infectious disease research.

Additional context:

• The antibody binds the CD3ε chain, a component of the TCR-CD3 complex required for T cell signaling, and thus its in vivo use directly impacts adaptive immune responses.
• In some formats, such as murinized or functional-grade preparations, 145-2C11 can be engineered for enhanced depletion via cytotoxicity or reduced immunogenicity, optimizing it for specific experimental needs.

145-2C11 is not recommended for formalin-fixed paraffin sections, but is extensively used for in vivo functional experiments with high-purity/low-endotoxin preparations for sensitive models.

Commonly used antibodies or proteins combined with 145-2C11 (anti-mouse CD3ε) in the literature include anti-CD4 and anti-CD8 antibodies, which are routinely applied for immunophenotyping of distinct T cell subsets using flow cytometry.

Other frequently used reagents or proteins in combination with 145-2C11 include:

• Anti-CD25: Used to identify and sort activated T cells (CD25 is the IL-2 receptor α chain).
• Anti-CD28: Employed as an additional costimulatory signal in T cell activation experiments to mimic physiological activation.
• Concanavalin A (Con A): Used for comparison as a general T cell mitogen when assessing activation versus 145-2C11-induced stimulation.
• Trucount beads or tubes: Utilized for accurate quantification of lymphocyte numbers after anti-CD3 administration.
• Glucocorticoids (e.g. methylprednisolone): Used to study or mitigate cytokine release syndrome that may result from 145-2C11 administration, as co-administration profoundly affects cytokine levels and immune responses.
• Fcγ receptor-blocking antibodies or modified Fc constructs: To examine the dependency of 145-2C11 effects on Fcγ receptor engagement and to compare wild-type versus Fc-modified antibodies.

Functional experiments involving cell activation or apoptosis with 145-2C11 also regularly monitor:

• Cytokines such as IL-2, TNF-α, IL-6, and TGF-β.
• Apoptotic markers and proliferation markers (e.g., Annexin V for apoptosis, CFSE for proliferation).
• Antibodies targeting other surface molecules, such as TCRβ (to confirm the presence of the TCR/CD3 complex), or F4/80 (to assess macrophage involvement or T cell phagocytosis).

Experiments may also use soluble versus plate-bound forms of the 145-2C11 antibody, different anti-CD3 clones (such as 2C11-Novi, a surrogate with modified Fc regions), isotype controls, and viability dyes.

In summary, anti-CD4 and anti-CD8 are the primary antibodies co-used with 145-2C11 for T cell subset analysis, often complemented by anti-CD25, anti-CD28, cytokine detection reagents, and functional antibodies depending on the experiment’s goal.

Clone 145-2C11 is a monoclonal antibody widely cited in scientific literature for its specific targeting of the mouse CD3ε subunit of the T cell receptor (TCR) complex, enabling investigation of T cell activation, proliferation, apoptosis, and depletion in various immunological contexts.

Key findings from 145-2C11 citations include:

• Induction of T cell activation and proliferation: 145-2C11 binds CD3ε, initiating intracellular signaling that activates T cells, promotes proliferation, and can lead to apoptosis, depending on experimental conditions and cell context.
• Blocking effects: It effectively blocks the binding of the 17A2 antibody to CD3ε+ T lymphocytes, making it useful in competitive binding studies.
• CD3-TCR complex modulation: 145-2C11 can cause rapid downregulation of surface TCR expression, with recovery of TCR levels typically observed within five days post-treatment in mice. This downregulation impairs T cell responsiveness to secondary stimuli for a limited time.
• Functional versatility: The antibody is used in a broad array of immunological applications, including:
  • Flow cytometry
  • In vitro and in vivo T cell activation and depletion
  • Immunoprecipitation
  • Immunohistochemistry (on acetone- or zinc-fixed sections)
  • Western blotting
  • Complement-mediated cytotoxicity
  • Apoptosis induction in immature thymocytes
  • Functional blocking assays
• Comparison with engineered variants: Studies compared 145-2C11 with Fc-mutated variants like 2C11-Novi, showing that its original Fc domain enables binding to Fcγ receptors and induces robust T cell proliferation and cytokine release. Engineered variants that do not bind FcγR have altered in vivo immunomodulatory effects.
• T cell depletion: 145-2C11 is utilized for in vivo depletion of T cells in mouse models, supporting studies on immune regulation and disease.
• Modeling autoimmune and inflammatory diseases: Oral or systemic administration of 145-2C11 has been shown to ameliorate symptoms in murine models of autoimmunity by modulating T cell responses and cytokine profiles.

In summary, 145-2C11 is a cornerstone research antibody in mouse immunology, enabling precise manipulation, characterization, and depletion of T cells through its specific interaction with the CD3ε chain of the TCR complex.

Dosing regimens of clone 145-2C11 (anti-mouse CD3ε antibody) in mice vary widely depending on the experimental model, intended immune modulation, dosing goals (e.g., T cell depletion vs. activation), and antibody format (intact vs. F(ab')₂ fragment). The typical range and regimens used in published mouse studies include:

• Single-dose regimens:

  • Doses as low as 20 μg per mouse and as high as 400 μg per mouse (intraperitoneally) have been reported.
  • Example: Single intraperitoneal injection of 20 μg 145-2C11 for T cell activation and CD3-TCR downregulation.
  • In T cell depletion experiments, a one-time 400 μg dose resulted in about 40% depletion of CD4⁺ T cells.

• Multiple-dose regimens:

  • For extended depletion or modulation, protocols often use repeated dosing (e.g., 150 μg F(ab')₂ fragment every other day).
  • Some studies employ 25 μg daily for five days for comprehensive T cell subset depletion.

• Format differences:

  • Intact antibody (whole IgG) is more likely to provoke cytokine release and T cell activation, at lower doses, compared to F(ab')₂ fragments.
  • F(ab')₂ fragments are preferred in models where minimizing Fc-mediated effects is needed, often used at comparable or slightly higher doses per injection.

• Route of administration:

  • Intraperitoneal (i.p.) injection is most common, but intravenous (i.v.) dosing is also possible depending on the model.

Examples from Key Studies

Factors Influencing Dose Selection

• Mouse strain (sensitivity to cytokine release or T cell depletion may differ)
• Disease model (autoimmunity, transplant, tolerance, etc.)
• Purpose (depletion, transient activation, expansion, tolerance induction)
• Antibody format (whole IgG triggers stronger immune signals via Fc binding; F(ab')₂ reduces cytokine storm risk but may require higher or more frequent dosing)

Summary of Dose Ranges

• Common single injection range: 20–400 μg/mouse
• Repeated injection protocols: often 25–150 μg per dose, 2–5 times
• Format matters: Whole antibody usually used at lower doses compared to F(ab')₂

In practice, regimen selection is experiment-specific and often determined empirically.

If you need details on a specific mouse model (e.g., NOD, C57BL/6), intended immune effect (activation vs. depletion), or a particular disease model, please clarify for more tailored information.