Introduction
Alpha1-Microglobulin (1M), also called protein HC, is a tubular plasma and tissue protein that belongs to the lipocalin transport protein superfamily for small hydrophobic molecules. It contains 184 amino acids and weighs 26-kDa (1-2). Mature 1M and bikunin (urinary trypsin inhibitor) result from a common precursor (3). 1M is found in blood both in free form and complex-bound to immunoglobulin A (IgA). It is involved in inflammatory and detoxification processes caused by immune system activation and extracellular heme catabolism (4-5). While increased excretion is detected in urine or serum shortly after tubular injury, 1M may predict acute kidney injury and the need for renal replacement therapy (6). Urinary 1M is useful for the early detection of nephropathy in type 2 diabetic subjects (7).

Principal of the Assay
The AssayMax Human alpha1-microglobulin ELISA (Enzyme-Linked Immunosorbent Assay) kit is designed for detection of human alpha1-microglobulin in plasma, serum, urine, saliva, milk, and cell culture supernatant. This assay employs a quantitative sandwich enzyme immunoassay technique that measures human alpha1-microglobulin in less than 4 hours. A polyclonal antibody specific for human alpha1-microglobulin has been pre-coated onto a 96-well microplate with removable strips. Alpha1-microglobulin in standards and samples is sandwiched by the immobilized antibody and biotinylated polyclonal antibody specific for human alpha1-microglobulin, which is recognized by a streptavidin-peroxidase conjugate. All unbound material is then washed away and a peroxidase enzyme substrate is added. The color development is stopped and the intensity of the color is measured.