Application Methods: IHC-Leica® Bond™, Immunofluorescence (Frozen), Immunofluorescence (Immunocytochemistry), Immunohistochemistry (Paraffin), Immunoprecipitation
Background: The protein phosphatase (PTP) receptor CD45 is a type I transmembrane protein comprised of a pair of intracellular tyrosine phosphatase domains and a variable extracellular domain generated by alternative splicing (1). The catalytic activity of CD45 is a function of the first phosphatase domain (D1) while the second phosphatase domain (D2) may interact with and stabilize the first domain, or recruit/bind substrates (2,3). CD45 interacts directly with antigen receptor complex proteins or activates Src family kinases involved in the regulation of T- and B-cell antigen receptor signaling (1). Specifically, CD45 dephosphorylates Src-family kinases Lck and Fyn at their conserved negative regulatory carboxy-terminal tyrosine residues and upregulates kinase activity. Conversely, studies indicate that CD45 can also inhibit Lck and Fyn by dephosphorylating their positive regulatory autophosphorylation site. CD45 appears to be both a positive and a negative regulator that conducts signals depending on specific stimuli and cell type (1). Human leukocytes including lymphocytes, eosinophils, monocytes, basophils, and neutrophils express CD45, while erythrocytes and platelets are negative for CD45 expression (4).
Application Methods: IHC-Leica® Bond™, Immunohistochemistry (Paraffin), Western Blotting
Background: Cluster of differentiation molecule 11b (CD11b)/Integrin alpha M (ITGAM) is a transmembrane protein forming heterodimers that are composed of α and β subunits (1). CD11b is expressed by, and commonly used as a marker for, myeloid lineage cells, including neutrophils, monocytes, macrophages, and microglia (2). CD11b is phosphorylated at Ser1126 (cytoplasmic tail) in neutrophils. Research has shown that this phosphorylation event plays a role for leukocytes traveling from the blood stream to tissues (3). Furthermore, genome-wide association studies have linked CD11b to autoimmune diseases, such as systemic lupus erythematous (SLE) (4).