Invitrogen™ Human LAG-3 ELISA Kit 

Description

The Human Lymphocyte-Activation Gene 3 (Hu LAG-3) (CD223) ELISA quantitates Hu LAG-3 in human serum, plasma, buffered solution, or cell culture medium. The assay will exclusively recognize both natural and recombinant Hu LAG-3. Principle of the method The Human LAG-3 solid-phase sandwich ELISA (enzyme-linked immunosorbent assay) is designed to measure the amount of the target bound between a matched antibody pair. A target-specific antibody has been pre-coated in the wells of the supplied microplate. Samples, standards, or controls are then added into these wells and bind to the immobilized (capture) antibody. The sandwich is formed by the addition of the second (detector) antibody, a substrate solution is added that reacts with the enzyme-antibody-target complex to produce measurable signal. The intensity of this signal is directly proportional to the concentration of target present in the original specimen. Rigorous validation Each manufactured lot of this ELISA kit is quality tested for criteria such as sensitivity, specificity, precision, and lot-to-lot consistency. See manual for more information on validation.

LAG-3 is a 70-kDa surface glycoprotein belonging to the Ig superfamily with homology to CD4. LAG-3 binds to MHC class II with higher affinity than CD4 and is thought to be involved in the negative regulation of T cell activation and homeostatic proliferation. Surface expression of LAG-3 has been reported on activated T cells (including regulatory T cells) and NK cells. CD8+ T cells usually express LAG-3 at significantly higher levels than CD4+ T cells. Coexpression of LAG-3 and CD49b has been proposed to identify human and mouse Type 1 regulatory T cells (Tr1 cells).