ELISA/assay

Surfactant Protein A (SP-A) ELISA

KBH7920

1 x 96 wells

Surfactant Protein A (SP-A) ELISA

Surfactant protein A (SP-A), the most abundant apoprotein of pulmonary surfactant, is a hydrophilic hybrid molecule that belongs to the Ca2+-dependent animal lectin superfamily termed collectins. SP-A has multiple functions including participating in tubular myelin formation, regulating the recycling of surfactant lipids, and acting synergistically with the two lipophilic surfactant apoproteins to lower surface tension. In addition, SP-A plays a major role in host defense of the lung: it is an essential component of innate immunity and helps to activate acquired immunity. SP-A can act either as a proinflammatory or anti-inflammatory agent, increasing or decreasing production of inflammatory cytokines by inflammatory cells to either enhance pathogen killing or suppress inflammation under basal conditions. Finally, it has been shown that SP-A levels are altered during a number of disease states including adult respiratory distress syndrome (ARDS) and cystic fibrosis. Concomitantly, exposure of SP-A to severe inflammation may cause oxidation or nitration of the protein and result in inactivation. Inactivation of SP-A during disease states may therefore cause increased susceptibility to secondary lung infections.

The method employs sandwich ELISA technique. Monoclonal antibodies are pre-coated onto microwells. Samples and standards are pipetted into microwells and Human Surfactant Protein A, SPA present in the sample are bound by the antibodies. Biotin labeled antibody is added and followed by Streptavidin-HRP is pipetted and incubated to form a complex. After washing microwells in order to remove any non-specific binding, the substrate solution (TMB) is added to microwells and color develops proportionally to the amount of Human Surfactant Protein A, SPA in the sample. Color development is then stopped by addition of stop solution. Absorbance is measured at 450 nm.

ELISA

Assay Kit

Cardiovascular

1 x 96 wells

0.217ng/ml

2-32ng/ml

40 ul

Serum, cell culture supernatant and plasma

70 minutes

RUO

wet

2-8C