CST, 29480L, Protein L (APC Conjugate)

Miscellaneous for studying in the research area. Product Usage Information Recommended Dilution: 1:50 Storage Supplied in PBS (pH 7.2), less than 0.1% sodium azide, and 2 mg/mL BSA. Store at 4°C. Do not aliquot the antibody. Protect from light. Do not freeze. Protocol Available protocols: Flow Cytometry (Live) Specificity / Sensitivity Protein L (APC Conjugate) is recombinantly derived and genetically engineered such as to remove the cell wall-, cell membrane-, and albumin-binding regions of Protein L to enhance binding to immunoglobulins. Conjugation to APC makes this product ideally suited for direct flow cytometric analysis of cells expressing κ light chain-containing immunoglobulins as well as immunoglobulin fragments that contain κ light chains, such as scFvs. Species Reactivity: Human, Mouse, Rat, Pig Background Protein L was first isolated from the surface of bacterial species (1). Unlike Protein A and Protein G which differentially bind to the Fc region of immunoglobulin isotype heavy chains, Protein L contains Ig binding domains that interact with the κ light chain variable domain without disrupting paratope function (2-4). This attribute not only facilitates binding to a broader range of immunoglobulin classes and subclasses than either Protein A or Protein G but also allows for binding to Fab fragments and single chain variable fragments (scFvs) that contain κ light chain sequences. Protein L does, however, display specificity with respect to κ light chain subtypes. In humans, Protein L binds to VκI, VκIII, and VκIV subtypes, whereas binding is restricted to VκI in mice (4).