Application Methods: IHC-Leica® Bond™, Immunohistochemistry (Paraffin)
Background: S100A8 and S100A9 are calcium-binding proteins that form a noncovalent heterodimer present in monocytes, neutrophils, macrophages, and some epithelial cells (1, 2). S100A8 and S100A9 are secreted by a tubulin-dependent mechanism during inflammatory conditions and have antimicrobial and chemotactic functions (3-5). Extracellular S100A8/S100A9 also induces an inflammatory response in endothelial cells, including induction of proinflammatory chemokines and adhesion molecules and increased vascular permeability (6). S100A8/S100A9 induces and recruits myeloid-derived suppressor cells (MDSC) in tumor-bearing mice (7). MDSC produce additional S100A8/S100A9 themselves, resulting in a positive feedback mechanism that sustains MDSC accumulation (7). S100A8/S100A9 is also highly expressed in psoriatic skin, where it directly upregulates transcription of complement protein C3, which contributes to disease (8). In addition, tumor-infiltrating myeloid cells induce expression of S100A8 and S100A9 in cancer cells, which increases invasiveness and metastasis (9).
|Human, Mouse, Rat|
Application Methods: Flow Cytometry, IHC-Leica® Bond™, Immunofluorescence (Immunocytochemistry), Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting
Background: Bim/Bod is a pro-apoptotic protein belonging to the BH3-only group of Bcl-2 family members including Bad, Bid, Bik, Hrk, and Noxa that contain a BH3 domain but lack other conserved BH1 or BH2 domains (1,2). Bim induces apoptosis by binding to and antagonizing anti-apoptotic members of the Bcl-2 family. Interactions have been observed with Bcl-2, Bcl-xL, Mcl-1, Bcl-w, Bfl-1, and BHRF-1 (1,2). Bim functions in regulating apoptosis associated with thymocyte negative selection and following growth factor withdrawal, during which Bim expression is elevated (3-6). Three major isoforms of Bim are generated by alternative splicing: BimEL, BimL, and BimS (1). The shortest form, BimS, is the most cytotoxic and is generally only transiently expressed during apoptosis. The BimEL and BimL isoforms may be sequestered to the dynein motor complex through an interaction with the dynein light chain and released from this complex during apoptosis (7). Apoptotic activity of these longer isoforms may be regulated by phosphorylation (8,9). Environmental stress triggers Bim phosphorylation by JNK and results in its dissociation from the dynein complex and increased apoptotic activity.