Description
Principle of the Assay::The Human Surfactant Protein D ELISA (Enzyme-Linked Immunosorbent Assay) kit is an in vitro enzyme-linked immunosorbent assay for the quantitative measurement of Human Surfactant Protein D in Cell Culture Supernatants, Serum. This assay employs an antibody specific for Human Surfactant Protein D coated on a 96-well plate. Standards and samples are pipetted into the wells and Surfactant Protein D present in a sample is bound to the wells by the immobilized antibody. The wells are washed and biotinylated anti-Human Surfactant Protein D antibody is added. After washing away unbound biotinylated antibody, HRP-conjugated streptavidin is pipetted to the wells. The wells are again washed, a TMB substrate solution is added to the wells and color develops in proportion to the amount of Surfactant Protein D bound. The Stop Solution changes the color from blue to yellow, and the intensity of the color is measured at 450 nm.
Background/Introduction: Surfactant, pulmonary-associated protein D, also known as SFTPD or SP-D, is a protein which in humans is encoded by the SFTPD gene. By fluorescence in situ hybridization, the SP-D gene was localized in 10q22.2-q23.1. On the basis of homology with other collectins, potential functions for SP-D include roles in innate immunity and surfactant metabolism, SP-D is produced in the bronchiolar and terminal epithelium of human fetal lung from about 21 weeks of gestation. What's more, SP-A and SP-D act as dual-function surveillance molecules that reverse orientation and function and become initiators of host-defense reactions