Anti-Mouse TIGIT [Clone 1B4] — Purified in vivo GOLD™ Functional Grade

Clone 1B4 is used for several different target antigens depending on the context; in mice, the most widely referenced "1B4" is a mouse monoclonal antibody against glial fibrillary acidic protein (GFAP), which is primarily used in brain and neural studies. This antibody is most commonly applied for immunohistochemistry, immunofluorescence, and Western blot analysis of mouse tissues to study astrocyte distribution and CNS pathology. There is no direct evidence in current sources that clone 1B4 is widely used for in vivo functional blocking, depletion, or therapeutic experiments in mice.

Summary of common in vivo applications of clone 1B4 in mice:

• Detection of GFAP expression in mouse CNS tissues via immunohistochemistry (IHC), often on both frozen and formalin-fixed, paraffin-embedded sections.
• Characterization of astrocytes and glial cells in studies of neurodevelopment, brain injury, and neurodegenerative disease models.
• Immunofluorescence for identifying astrocyte populations in tissue-cultured cells and ex vivo preparations.

Key details:

• Clone 1B4 specifically recognizes GFAP in mouse brain homogenates as well as in multiple other species; it is valuable for distinguishing astrocytes from other glia.
• There is no evidence that clone 1B4 is used for direct in vivo manipulation (e.g., depletion/blockade) of GFAP in live mice—its main applications are ex vivo tissue analysis following in vivo experimentation.

Alternative clone 1B4 applications (not GFAP-related):

• Other "1B4" clones exist for different proteins (e.g., anti-TIGIT, anti-IL8, anti-SNRPB), but these are not standard for in vivo work in mice and are not widely referenced for functional manipulation or therapy in mouse models.

Conclusion:
Clone 1B4’s primary in vivo-related use in mice is as a research tool for ex vivo immunodetection of GFAP in CNS tissues following in vivo experiments, especially via immunohistochemistry and immunofluorescence, rather than for direct functional studies in live animals.

Several different antibodies and proteins co-occur with 1B4 in the literature, but which "1B4" is referenced depends on the biological context. Based on the search results, the most frequently referenced antibodies/proteins used with 1B4 include:

• Anti-CR1 Monoclonal Antibody 1B4 (Complement Receptor 1 context):

  • Frequently paired with anti-PfRh4 monoclonal antibody 10C9 to detect and analyze interactions between the Plasmodium falciparum adhesin PfRh4 and CR1 in immunoprecipitation and Western blot experiments.
  • Both 1B4 and 10C9 are used in parallel to confirm binding specificities and characterize protein complexes.

• Anti-TIGIT Monoclonal Antibody 1B4 (Immune Checkpoint Inhibitor context):

  • Commonly used in combination with anti-PD-1 antibodies in mouse tumor models, especially to investigate synergistic effects in immunotherapy experiments. The anti-TIGIT 1B4 clone is used alone and alongside anti-PD-1 to study effects on tumor regression and immune cell activity.
  • In some studies, comparisons may be made to anti-CTLA-4, but the primary combination is with anti-PD-1.

• Anti-CD18 Monoclonal Antibody 1B4 (Integrin context):

  • Studies focusing on humanization of murine anti-CD18 mAb 1B4 often include a variety of human and murine immunoglobulin frameworks or isotypes for comparison (e.g., Gal/Rei, Gal/Len, Jon/Rei, New/Rei, hemichimeric antibodies). These provide both controls and comparators for avidity and immunogenicity studies but are not always other functional antibodies.
  • Additional detection or characterization can use anti-idiotypic antibodies (to recognize the idiotype of h1B4) or anti-constant-region antibodies.

• Antibodies Specific to Related Proteins/Receptors:

  • In receptor studies, such as those related to leukotriene B4 receptor (BLTR), investigators use monoclonal antibodies specific to BLTR, BLTR2, CysLT1, and CysLT2 for specificity controls during ELISA, flow cytometry, and immunocytochemistry, though these are not always named 1B4.

Summary Table: Common Antibodies/Proteins Used with 1B4

Key points:

• The identity of the paired antibody/protein depends on whether 1B4 is anti-CR1, anti-TIGIT, anti-CD18, or another specificity.
• In functional assays, 1B4 is typically used with antibodies to the interacting protein or with checkpoint inhibitor antibodies to study synergy or antagonism.
• Controls (such as anti-idiotypic Abs or isotype controls) and antibodies to related receptors are also routinely included depending on the assay type.

The clone 1B4 most prominently refers to a monoclonal antibody against TIGIT (an immune checkpoint protein). Key scientific findings from citations related to clone 1B4 are as follows:

• Clone 1B4 is a blocking anti-TIGIT antibody. It antagonizes TIGIT function rather than activating it.
• 1B4 enhances T cell responses: Mice treated with clone 1B4 show increased antigen-specific T cell proliferation and higher secretion of pro-inflammatory cytokines IFN-γ and IL-17.
• Promotes autoimmune pathology: When tested in the experimental autoimmune encephalomyelitis (EAE) model, treatment with clone 1B4 led to exacerbation of disease, with significantly increased lesions in the CNS, especially in meninges and parenchyma, and increased frequencies of pathogenic Th17 cells.
• Comparison with TIGIT agonists: Other clones (e.g., 4D4, 1G9) act as TIGIT agonists and suppress disease severity, T cell proliferation, and Th17 cell infiltration, unlike clone 1B4.
• In viral infection models: Treatment with clone 1B4 in chronic LCMV-infected mice showed no significant differences in TNF-α production by CD8+ T cells, suggesting possible context-dependent effects.

Additional findings on unrelated uses of "1B4" include:

• Clone 1B4 in plant research: Overexpression in Populus clone 717-1B4 leads to high ethylene, stem dwarfism, and altered wood properties.
• Clone 1B4 as an anti-MYD88 antibody: Used in biomedical research for immunoassays, though detailed functional data are not prominent in citations.
• Clone 1B4 as an anti-PcrV antibody: Used as a positive control for binding affinity studies in Pseudomonas aeruginosa research.

Summary Table: Major Scientific Findings for Clone 1B4

In immunological research, clone 1B4 is primarily recognized as a TIGIT-neutralizing antibody that boosts inflammatory T cell responses and worsens autoimmunity when TIGIT's inhibitory function is blocked. In other biomedical and plant research contexts, "1B4" refers to separate clones with distinct biological or technical applications.

Dosing regimens of clone 1B4 (an anti-TIGIT antibody) in mouse models generally involve intraperitoneal administration at doses ranging from 100 µg to 200 µg per mouse per injection, but schedules and total number of doses vary by model and experimental aim.

Key details by study/model:

• In an autoimmune encephalomyelitis (EAE) model, clone 1B4 was administered at 200 µg per mouse, injected multiple times (exact intervals not always specified, but often 3–4 times) in concert with peptide immunization to assess T-cell response and disease severity.

• A protocol investigating PD-1 and TIGIT synergy used clone 1B4 at 100 µg per dose, given on specified consecutive days (for example, days 1, 3, and 5 post-randomization), typically by intraperitoneal route.

• A general reference for immune checkpoint blockade recommends doses up to 200 µg per dose, spaced every three days, but cautions that a fourth high dose in some ICB (immune checkpoint blockade) regimens can increase risk of adverse effects or mortality, underscoring the need to adapt dose/frequency based on the model and health status of the mice.

Summary Table:

Additional context:

• Clone 1B4 acts as a TIGIT-blocking antibody, leading to increased T-cell activation and exacerbation of autoimmunity (e.g., worsened EAE).

• Route of administration is typically intraperitoneal; rarely, alternative routes are used depending on the model.

• Always monitor for model-specific toxicity or exaggerated immune response, especially with higher or repeated doses, as the immune context (autoimmunity vs. tumor) affects both dosing and expected outcomes.

• Dose and schedule may need adjustment for models of chronic disease versus acute immune activation, or when used in combination with other immunomodulators.

Conclusion:
Clone 1B4 is most commonly used at 100–200 µg per injection, 2–4 times per study, spaced by several days; precise schedules are tailored to the model and experimental question. Always refer to published studies most relevant to your disease model and consider species-specific responses if extrapolating to new systems.