Anti-Mouse IFNα (Clone TIF-3C5) – Purified in vivo GOLD™ Functional Grade

Clone TIF-3C5 is a monoclonal antibody used in in vivo mouse studies to specifically neutralize mouse interferon alpha (IFN?), particularly subtypes IFN-?A, -1, -4, -5, -11, and -13, without cross-reacting with mouse IFN? or IFN?.

In experimental models, TIF-3C5 is administered—typically via intraperitoneal injection at various doses and schedules—to block the activity of mouse IFN? during immune responses or infection. For example:

• West Nile Virus model: Mice are given TIF-3C5 (commonly 250–500 ?g per dose) on schedules such as one day prior, and one and three days after infection. Blocking IFN? with TIF-3C5 leads to increased lethality following West Nile Virus infection, indicating the antibody’s efficacy in neutralizing IFN? and demonstrating the essential antiviral function of endogenous IFN?.
• Functional details: TIF-3C5 has a circulating half-life of about 4 days in mice, providing a useful time frame for blocking experiments.
• Experimental outcomes: Enhanced viral susceptibility and lethality from West Nile Virus infection in wild-type mice treated with TIF-3C5 mirrors the phenotype seen in IFN? pathway knockout mice (e.g., Irf7^-/-^), confirming the antibody’s in vivo neutralization of IFN?.

Essentially, TIF-3C5 is used as a tool to dissect the role of IFN? in antiviral immunity, immune regulation, and disease models by antibody-mediated neutralization in live animals.

Key details:

• Dose and administration: Typical regimens are 250–500 ?g per dose, administered intraperitoneally at multiple time points around infection or immune challenge.
• Specificity: Binds only to mouse IFN? and not IFN? or IFN?, allowing selective functional blockade of type I IFN-? signalling in vivo.

Researchers use TIF-3C5 in vivo to assess the biological and immunological consequences of IFN? blockade in various disease and infection models in mice.

The correct storage temperature for sterile packaged clone TIF-3C5 (anti-mouse IFN alpha monoclonal antibody) depends on the intended storage duration:

• Short-term storage (up to 1 month): Store at 2–8°C (refrigerated).
• Long-term storage: Store at -20°C or lower.

For maximum stability during extended storage, aliquot the antibody aseptically and avoid repeated freeze-thaw cycles. Ensure storage is sterile and at the recommended temperature to maintain product integrity.

Commonly used antibodies and proteins paired with TIF-3C5 (an anti-mouse IFN-? antibody) in the literature include:

• HD?-4A7 (anti-IFN-?): This monoclonal antibody is frequently used alongside TIF-3C5 to dissect the specific roles of IFN-? and IFN-? in murine models, particularly in studies of viral infection and immune modulation. Their selective blockade enables researchers to independently examine the consequences of neutralizing each interferon subtype.
• MAR1-5A3 (anti-IFNAR1): This antibody targets the type I interferon receptor (IFNAR1) and is often used in parallel with TIF-3C5 to block all type I interferon signaling, since IFNAR1 is required for signal transduction of both IFN-? and IFN-?. This helps distinguish between the effects of broad type I IFN blockade and more selective inhibition.

Additional proteins and reagents that may be used in combination with TIF-3C5, depending on experimental context:

• Recombinant IFN-? subtypes (e.g., IFN-?A, -1, -4, -5, -11, -13) for specificity and neutralization assays.
• Isotype control antibodies, used as negative controls to confirm that observed effects are due to specific antibody blocking.

Summary table:

The use of these antibodies, particularly HD?-4A7 and MAR1-5A3, is well-documented in studies investigating the immunological roles of type I interferons in mouse models.

Clone TIF-3C5 is a monoclonal antibody that specifically binds and neutralizes several mouse IFN? subtypes (IFN-?A, -1, -4, -5, -11, and -13), but does not react with mouse IFN? or IFN?. Key scientific findings from literature citations of clone TIF-3C5 include:

• Subtype Specificity: TIF-3C5 recognizes a shared epitope among listed mouse IFN? subtypes, with no binding to IFN? or IFN?. This allows for selective blockade of IFN? without affecting other type I or II interferons.

• In Vitro Functional Activity:

  • TIF-3C5 efficiently blocks IFN?-induced Stat1 phosphorylation and the induction of MHC-I (H2-Kb) expression in cell lines (e.g., L929, fibrosarcoma), in a dose-dependent manner.
  • TIF-3C5 neutralizes the antiviral activity of both recombinant and natural IFN? in vitro, as shown by loss of protection in L929 cells infected with vesicular stomatitis virus (VSV) when IFN? signaling is blocked.
  • The blocking efficiency varies between subtypes, e.g., it is highly effective against IFN-?1 at low antibody concentrations (ID${50}$ = 9 ng/well), while much higher doses are needed for IFN-?4 (ID${50}$ = 2000 ng/well).

• In Vivo Activity:

  • TIF-3C5 circulates with a half-life of approximately 4 days in mice.
  • Administration of TIF-3C5 leads to increased mortality in mice infected with West Nile Virus (WNV), mimicking the susceptibility seen in IRF7 knockout mice. This underscores the vital role of IFN?-mediated protection against viral infection.
  • Notably, the increased lethality did not always reach statistical significance depending on the dosing regimen and experimental conditions.

• No Neutralization of IFN? or IFN?:

  • TIF-3C5 is highly specific and does not interfere with IFN? or IFN? bioactivity, which is critical for experiments aiming to dissect IFN?-specific roles.

• Research Applications: TIF-3C5 is widely used to selectively investigate the biological and immunological roles of mouse IFN?, including studies of antiviral defense, cytokine signaling, and viral pathogenesis.

In summary, the most cited and characterized findings for clone TIF-3C5 are its selective neutralization of multiple murine IFN? subtypes, dose-dependent blockade of IFN?-mediated cellular responses, and its pivotal use in dissecting the functional contributions of IFN? in mouse models of infection and immunity.