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.
PC3 (PC-3) human prostate cancer cell line is one of the cell lines used in prostate cancer research. These cells are useful in investigating the biochemical changes in advanced prostatic cancer cells and in assessing their response to chemotherapeutic agents. They can be used to create subcutaneous tumors in mice in order to investigate a model of the tumor environment in the context of the organism additionally. PC3 cells have high metastatic potential compared to DU145 cells which have a moderate metastatic potential and to LNCaP cells which have low metastatic potential.
PC3 cell line was established in 1979 from bone metastasis of grade IV of prostate cancer in a 62-year-old Caucasian male. These cells do not respond to androgens, glucocorticoids, or epidermal or fibroblast growth factors.
PC3 have low testosterone-5-alpha reductase and acidic phosphatase activity, do not express PSA (prostate-specific antigen), and are PSMA-negative (prostate-specific membrane antigen).
Furthermore, karyotypic analysis show that PC3 are near-triploid, presenting 62 chromosomes. Q-band analysis revealed no Y chromosome. From a morphological point of view, electron microscopy revealed that PC3 show characteristics of poorly-differentiated adenocarcinoma. They have features common to neoplastic cells of epithelial origins, such as numerous microvilli, junctional complexes, abnormal nuclei and nucleoli, abnormal mitochondria, annulate lamellae, and lipoidal bodies.