SH3BP2 Antibody, Biotin conjugated

Basic Research Questions

• What is SH3BP2 and what cellular functions does it regulate?

  SH3BP2 is an adaptor protein primarily expressed in immune cells, including macrophages, B cells, and T cells. It functions by regulating intracellular signaling through interactions with various proteins such as Syk, phospholipase Cγ, Vav, and Src . SH3BP2 plays critical roles in immune cell function and bone metabolism. At the molecular level, it binds differentially to SH3 domains of certain proteins in signal transduction pathways and interacts with phosphatidylinositols, connecting hemopoietic tyrosine kinase fes to the cytoplasmic membrane in a phosphorylation-dependent mechanism . Research has demonstrated SH3BP2's involvement in autoimmune diseases, with both gain-of-function mutations and deficiencies showing modulatory effects on disease progression in lupus models .

• What is the advantage of using a biotin-conjugated SH3BP2 antibody versus non-conjugated versions?

  Biotin-conjugated antibodies offer several methodological advantages over non-conjugated antibodies. The biotin-streptavidin system provides signal amplification due to the high affinity binding (Kd ≈ 10^-15 M) between biotin and streptavidin, enhancing detection sensitivity—particularly valuable for low-abundance proteins like SH3BP2. In sandwich ELISA applications, the biotin-conjugated SH3BP2 antibody acts as a detection antibody that binds to the target protein already captured by immobilized antibodies . This system allows for flexible detection using streptavidin-conjugated reporter enzymes such as HRP, enabling colorimetric signal development proportional to SH3BP2 concentration . Additionally, biotin-conjugated antibodies facilitate multiplex detection systems and can be used in protocols requiring sequential probing without cross-reactivity concerns.

• What are the key characteristics of the SH3BP2 Antibody, Biotin conjugated?

  The SH3BP2 Antibody, Biotin conjugated is a polyclonal antibody derived from rabbits with IgG isotype . Its primary application is in ELISA, particularly in sandwich ELISA formats where it serves as the detection antibody following target capture . The antibody demonstrates reactivity with human SH3BP2 and is formulated in liquid form . It recognizes SH3BP2 (also known by alternative names including 3BP2, CRBM, CRPM, RES4-23, and TNFAIP3 interacting protein 2) . The antibody should be stored at -20°C or -80°C according to manufacturer recommendations to maintain optimal activity . Its high specificity for SH3BP2 makes it suitable for sensitive detection without significant cross-reactivity with analogous proteins .

• How does SH3BP2 function in immune cell signaling pathways?

  SH3BP2 functions as a critical scaffold protein in immune cell signaling through multiple interactions with signaling molecules. In immune cells, SH3BP2 regulates various cellular functions by interacting with key signaling proteins including Syk, phospholipase Cγ, Vav, and Src . These interactions facilitate signal transduction from surface receptors to downstream effectors. SH3BP2 appears to play significant roles in both innate and adaptive immune responses, as evidenced by studies showing its involvement in macrophage, B cell, and T cell function . In the context of autoimmune disease models, SH3BP2 modulates immune responses through several mechanisms. In lupus models, gain-of-function mutation in SH3BP2 ameliorates disease phenotypes by reducing anti-dsDNA antibody titers and autoreactive lymphocytes . Conversely, SH3BP2 deficiency also reduces lupus-like phenotypes, including suppressing autoantibody production (anti-dsDNA antibody and rheumatoid factor), reducing the aberrant accumulation of double-negative T cells, and decreasing T cell activation .

• What are the main tissues and cell types where SH3BP2 is expressed?

  SH3BP2 demonstrates a predominantly immune cell-specific expression pattern. It is highly expressed in macrophages, B cells, and T cells, making it a critical protein in immune system function . Studies have shown that SH3BP2 is particularly important in myeloid lineage cells, where it plays roles in inflammatory responses and osteoclastogenesis through SYK signaling . Beyond immune cells, research has revealed SH3BP2 expression in neural tissues, particularly at neuromuscular junctions where it interacts with postsynaptic proteins including acetylcholine receptor (AChR) subunits, Low-density lipoprotein 4 (Lrp4), and components of the dystroglycan complex . When designing experiments targeting SH3BP2, researchers should consider these tissue expression patterns to select appropriate models and controls, particularly when exploring SH3BP2 function in autoimmune conditions, bone metabolism disorders, or neuromuscular junction development.