Clone BB7.6 is a mouse monoclonal antibody targeting the human MHC class I molecules HLAA2 and HLAB7, and it is formulated for use in in vivo studies in mice, primarily to modulate, deplete, or track human MHC class Iexpressing cells in xenograft or humanized mouse models.

• In in vivo mouse studies, BB7.6 is administered to mice that have been engrafted with human cells (such as in humanized mouse models) to:

  • Block or deplete human HLAA2/B7positive cells by antibodymediated mechanisms, which can include antibodydependent cellular cytotoxicity (ADCC) or complementmediated lysis depending on the experimental setup.
  • Modulate immune responses by binding to MHC class I molecules on human cells, thereby impacting T cell recognition and function in contexts such as graft rejection or studies of human immune cell behavior.

• This antibody is specifically purified and formulated with low endotoxin levels (<1.0 EU/mg), making it suitable for injection into mice with minimal adverse reactions and optimal functionality in immunological experiments.

• Typical applications in in vivo mouse studies include:

  • Testing graft survival or rejection in human stem cell or tumor xenograft models.
  • Studying human immune cell engraftment, localization, or depletion in immunodeficient or humanized mouse models.
  • Investigating immune modulation, such as inhibiting interactions between human MHC class I molecules and mouse or humanderived T cells, and assessing consequences for disease, immune activation, or tolerance.

• The use and dosing of BB7.6 in in vivo studies are protocoldependent; investigators are advised to refer to lotspecific datasheets for recommended concentrations, injection routes, and schedules for optimal efficacy and safety.

Summary Table: Usage of BB7.6 in In Vivo Mouse Studies

BB7.6 is not used for targeting mouse H2 MHC molecules, but specifically recognizes human HLA class I antigens, making it valuable in studies requiring discrimination between mouse and human immune components. Always consult productspecific datasheets and protocols for detailed handling instructions.

Commonly used antibodies or proteins in the literature with BB7.6 (an antiBw6 monoclonal antibody targeting specific HLA class I epitopes) include other antibodies directed against Bw4 and Bw6 epitopes, such as SFR8B6 (antiBw6), and a collection of both mouse and human monoclonal antibodies recognizing Bw4 and Bw6 variants.

Essential context:

• BB7.6 is typically paired with other antiHLA antibodies, notably those recognizing Bw4 epitopes, in comparative or combinatorial binding studies. These combinations help define epitope specificity and allelic heterogeneity. For example, studies use BB7.6 alongside several antiBw4 mouse monoclonal antibodies and other antiBw6 antibodies like SFR8B6.
• In research on epitope mapping, sitedirected mutagenesis and antibody binding analysis often involve multiple antibodies targeting overlapping or adjacent HLA regions (positions 77–83 and others) to characterize the molecular footprints of each antibody.

Additional relevant antibodies and proteins commonly used in combination research:

• AntiBw4 mAbs: Multiple mouse and human monoclonal antibodies against Bw4 are assessed together with BB7.6 to explore crossreactivity and epitope overlap.
• Other antiBw6 mAbs: Human and mouse antiBw6 antibodies, such as those found in alloantisera, are tested alongside BB7.6 to study variant binding affected by single amino acid substitutions.
• KIR3DL1 allotypes: These are not antibodies but are natural killer cell receptors that also interact with Bw4 and Bw6 epitopes and are often included in HLA binding studies for comparison.
• Other HLAreactive antibodies: Studies sometimes employ broadly reactive antiHLA antibodies (not just Bw4/Bw6) to profile binding patterns across diverse alleles.

In cancer immunotherapy or diagnostic contexts, antibodies such as antiPD1 are sometimes combined with other specific antibodies (e.g., in bispecific formats or sequential treatments), but this is less typical for BB7.6, whose primary use is in HLA specificity mapping rather than direct clinical therapy.

Summary: Antibodies/proteins most frequently paired or compared with BB7.6

• AntiBw4 mAbs (mouse and human)
• Other antiBw6 mAbs (mouse and human, including SFR8B6)
• Occasionally, natural KIR proteins (e.g., KIR3DL1) for comparative binding studies

Clone BB7.6 is a monoclonal antibody used extensively in scientific literature to characterize HLA class I Bw6 epitopes and analyze their molecular structure and antibody interactions.

Key findings from citations referencing clone BB7.6 include:

• Epitope Specificity: Clone BB7.6 recognizes the Bw6 public epitope on HLA class I molecules. It is highly sensitive to specific amino acids in the 77–83 region of the HLA molecule, particularly at positions 82 and 83. Experimental studies using sitedirected mutagenesis have shown that substitution of amino acid residue 83 (from glycine to arginine, G83R) completely destroys BB7.6 binding, probably due to steric hindrance. Similarly, single substitutions at residue 82 (R82L) severely reduce binding by BB7.6.

• Structural Implications: The precise amino acids recognized by BB7.6 are exposed on the HLA surface and make energetically significant contacts with the antibody. This highlights that antibodyepitope recognition is often dictated by a limited set of amino acids, conferring BB7.6 a sharp specificity that assists in differentiating Bw6 epitope variants.

• Bw4/Bw6 Heterogeneity: BB7.6 has helped define that the Bw4 and Bw6 epitopes are not singular but represent families of related structures, and small mutations can switch HLA molecules from being recognized by antiBw6 (like BB7.6) to antiBw4 antibodies and vice versa.

• Utility in Research: BB7.6 is frequently used to assess alterations in HLA molecules caused by mutations or diseaserelated polymorphisms. This enables structuralfunctional mapping of the HLA region critical for immune recognition and transplantation immunology.

In summary, clone BB7.6 is instrumental in defining the molecular details of the HLABw6 epitope and in advancing our understanding of HLA diversity, antibody specificity, and NK cell interactions in the context of immunity and transplantation.

There is insufficient direct published data specifically detailing how dosing regimens of clone BB7.6 (an antiHLAA2 monoclonal antibody) vary across different mouse models in the search results provided. Standardized antibody dosing regimens in murine studies typically depend on several factors, including:

• Mouse strain and genetic background, which can influence pharmacokinetics and immune responses.
• Intended application (e.g. in vivo depletion vs. neutralization, immunogenicity testing, or imaging).
• Route of administration (intraperitoneal, intravenous, etc.) and dosing frequency.

General patterns for antibody dosing in mouse models:

• Depleting or functional antibodies (e.g., antiCD4, antiCD8, antiLy6G): conventional doses range from 100–300 µg per mouse, given intraperitoneally every 3 days or 1–3 times per week, depending on functional persistence and study endpoint.
• Immuneactivating antibodies: doses may be lower (5–50 µg per mouse, i.v.), especially for T cellactivating agents, to avoid severe cytokine release.

Variability across mouse models:

• Immunodeficient and humanized mice may receive personalized regimens, often with lower or more frequent dosing to account for altered immune clearance or target expression.
• Transgenic strains and wildtype mice may metabolize antibodies differently, impacting the effective duration and frequency of dosing.
• Some mouse strains (e.g., NOD/SCID, C57BL/6) are preferred for certain functional antibodies because they either express or lack specific target antigens.

For BB7.6 specifically:
BB7.6 is most commonly used for cell depletion or in vivo tracking of HLAA2 in humanized or transgenic mice. Where explicit regimens are not available, investigators default to general murine antibody dosing guidelines above, modifying dose and schedule based on pilot experiments and monitoring of pharmacodynamic markers.

Summary table: General Antibody Dosing in Mouse Models

Key considerations:

• Experimental outcomes (immunogenicity, depletion efficiency, adverse reactions) can vary with mouse strain, age, sex, and health status.
• Dosing should always be piloted and titrated for new models or novel clones due to interanimal and interstrain variability.

In sum:
While direct published BB7.6 dosing regimens in various mouse models are not found in the current results, general antibody dosing for in vivo studies typically ranges from 100–300 µg/mouse i.p. every 3 days for depletion studies, with adjustments made depending on mouse strain, experimental aim, and observed effects.