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Publisher Summary The chapter discusses the methods of culture of human pancreatic ducts and their applications. Human pancreas are obtained either at immediate autopsy, at routine autopsy (within 3 hours of death), or at surgery and returned to the laboratory. Under sterile conditions and using sterile techniques, the main duct is opened and the entire length of the pancreas is dissected out and placed in cold L-15 medium. The chapter discusses the source, isolation, and culture conditions of ductal cells. Viable human pancreatic ductal cells are maintained in vitro by means of explant procedure for up to 2 months. Human pancreatic ductal explants are successfully xenotransplanted into athymic “nude” mice. The utilization of human pancreatic ductal tissue in long-term organ and cell cultures has made it possible to study the effects of chemical carcinogens on this important target tissue by our laboratories and these techniques make it possible to study the pathogenesis of human pancreatic cancer under in vitro conditions.

Publisher Summary This chapter provides information on lung tumors in mice, with emphasis on the use of mouse lung for quantitative investigations in carcinogenesis, especially bioassay of chemicals for carcinogenic activity. The lung-tumor response in strain A mice is easily and clearly positive to all major types of chemical carcinogens. Strain A mice are the most susceptible to a wide variety of carcinogens, in terms of the earlier appearance and greater multiplicity of tumors. The lung-tumor response in strain A mice is easily and clearly positive to all major types of chemical carcinogens. Estrogenic and other steroid hormones, with the targets of endocrine-regulated tissues, are an exception. The lung tumor of the mouse has demonstrated its ability to pick up undetected, unpredicted neoplastic responses such as to urethane and to isoniazid. The carcinogens picked up by the lung tumor system have been shown to be carcinogenic for other tissues and in other species of animals. The mouse lung tumor is a reproducible, stable, and rapid biological model for a wide variety of quantitative investigations in carcinogenesis. It provides a three-dimensional lattice of the lung in which a known, identifiable subpopulation of cells—the type 2 alveolar pneumocytes—can be accelerated into conversion into neoplasms.

Publisher Summary This chapter describes the explant culture of human peripheral lung. Fragments of fetal or adult lung have been cultured from human or animal species and on various substrates such as membrane filters on stainless steel grids, lens paper. Prior to culture, the lung specimens consist of typical alveolar structures lined with epithelial cells. The alveoli in specimens from some patients are nearly filled with macrophages, whereas in other cases they contain only a small number of macrophages. Connective tissue composed of fibroblast cells, collagen, and elastin often surrounds the alveolar structures. Terminal bronchiolar cells and endothelial cells are also observed. The alveoli of fresh tissue contained type-1 epithelial cells with extended cytoplasm and type-2 epithelial cells. Gaseous exchange occurs across the cytoplasm of the type-1 cells. Type-2 cells contained intracytoplasmic lamellar inclusion bodies that corresponded to the darkly stained inclusions observed in the cytoplasm of these cells with light microscopy. The alveolar walls remained intact in the peripheral portions of the explants for relatively long periods of time.

Publisher Summary This chapter examines the identification and culture of human bronchial epithelial cells. The development of methods for culturing human bronchial epithelial cells would permit analysis of factors that influence their normal differentiation and of the effects of chemical carcinogens and other toxins on these important target cells in human lung disease. The proliferative and differentiative characteristics of human bronchial epithelial cells in primary culture are described. Although ciliary activity is observed in some epithelial cells in primary culture for as long as 6 months, the majority of these cells differentiated to a keratin-producing squamous epithelium. The labeling index of epithelial cells and fibroblasts in the outgrowth is determined in primary cultures that have been incubated for a period of 25 days. Outgrowths of bronchial cells are fixed and washed and are reacted by indirect immunofluorescence with rabbit antibodies against purified fibronectin from fresh human serum. The ciliary activity, detected by localized movement of culture medium over the epithelial cells in the explant and in the outgrowth, is observed in cultures maintained for at least 6 months.

Publisher Summary This chapter discusses the selective isolation of epithelial cells in primary explant cultures of human and animal tissues. There are many methods employed for the selective isolation of epithelial cells from fragments of human or animal tissues. Flaxman cultured pieces of human skin in plasma clots on coverslips and obtained outgrowths composed of epidermal keratinocytes in a proliferative state. Only 5% of the cultures exhibited some fibroblast outgrowth. Success in obtaining purified cultures of mammary epithelial cells occurred only when the collecting ducts were dissected free from the surrounding connective tissue prior to placing them in culture. Cole and DeVellis derived relatively pure populations of glial and nerve cells by culturing fragments of human and animal brain tissues between pieces of perforated cellophane in Petri dishes. The fibroblasts and other connective tissue cells migrated through the cellophane perforations to the floor of the dishes while the glial and nerve cells migrated and extended their processes between the two layers of cellophane. The pigskin technique involves the culture of pieces of minced tissue on pigskin. The cells that grew generally retained the morphological and functional features of the organ in vivo.