Immunoprecipitation is a technique in which an antigen is isolated by binding to a specific antibody attached to a sedimentable matrix. It is also used to analyze protein fractions separated by other techniques such as gel filtration or density gradient sedimentation. The source of antigen for immunoprecipitation can be unlabeled cells or tissues, metabolically or intrinsically labeled cells, or in vitro-translated proteins. This unit describes a wide range of immunoprecipitation techniques, using either suspension or adherent cells lysed by various means.Usually, plasmas transfected cells or natural cells are ideal sample for immunoprecipitation.
The A549 cell line was first developed in 1972 b D.J Giard, et al. through the removal and culturing of cancerous lung tissue in the explanted tumor of 58-year-old caucausian male. The cells produce adenocarcinomic alveolar basal epithelial cells with a modal chromosome number of 66. This type of cell squamous and performs the task of diffusing water, electrolytes and other substances across the surface of the alveoli in a normal lung.
The cell line is hypotriploid with a modal chromosome number of 66, which occurs in 24% of cells, modal number 64 and 67 is relatively common with higher ploidies occurring at an infrequent rate (0.4%).