B lymphocyte-enriched cell populations cultured with mitogens in initial suspension cultures formed colonies in soft agar when the same mitogenic agent was present in the lower layer of a two-layer soft agar system. Colony formation depended upon the presence of T cells in the initial culture, and was optimal after an initial 72-h culture with phytohemagglutinin (PHA; 12.5 microliters/ml), poke...

We report on a new optofluidic platform that combines optoelectronic tweezers (OET) 1 with patterned growth patches coated with extracellular matrix for long-term culture of individual adherent cells. The current device has a 10x10 array of growth patches, each with 0.5mm diameter to allow for expansion of colonies to about 250 cells. The OET platform allows selection of desired single cells be...

A method has been described for the long-term culture of human bone marrow cells in liquid medium. Hematopoiesis, as measured by the production of granulocytic-macrophage progenitor cells (CFUc), continued for at least 20 weeks and was dependent upon the presence of a marrow-derived adherent layer of cells. As in the case of murine marrow liquid cultures, the adherent layer consisted of mononuc...

Mammary epithelium and surrounding stroma have been maintained in an expiant system for 1 to 6 months and subse quently xenografted into athymic nude mice. The morphologi cal characteristics of 26 cases of normal human mammary epithelium in long-term expiant culture were described, using high-resolution light and electron microscopy. Normal human breast tissue specimens were obtained from immed...

The lipid composition of leukocytes maintained in long-term culture was examined in order to clarify the role of immaturity in previously observed differences between normal mature leukocytes and leukemic cells. Cell cultures derived from three types of leukocytes were examined: normal lymphocytes, Burkitt lymphoma, and chronic myelocytic leukemia. Lipid extracts were analyzed for total lipid w...

BACKGROUND Extensive bile duct proliferation is a key feature of the tissue reaction to clinical and experimental forms of liver injury. Experimental infection of mice by Schistosoma mansoni is a well-studied model of liver fibrosis with bile duct hyperplasia. However, the regulatory mechanisms of bile duct changes are not well understood. In this study we report the reproducible isolation of l...

Clonal culture systems using semisolid media for the detection of granulocyte-macrophage (Bradley and Metcalf 1966; Pike and Robinson 1970; Pluznik and Sachs 1966), erythroid (Stephenson et al. 1971), lymphoid (Fibach et al. 1976; Metcalf et al. 1975a; Sredni et al. 1976) and megakaryocytic (Metcalf et al. 1975b) progenitors have contributed greatly to investigations of hematopoiesis. Unfortuna...

Beating salamander hearts were maintained in tissue culture for periods ranging from 1 to 6 months. After 1, 3, or 6 months of culture, six hearts, along with six control hearts, were fixed for electron microscopy. In control tissue, the sarcoplasmic reticulum usually demonstrated the normal pattern of paired, linearly arranged membranes, although in some cases, the reticulum showed a variation...

Rabbit corneas cultured in a serum-free, dextran-supplemented medium maintained a high rate of incorporation of H-glucosamine into glycosaminoglycans (GAG) for several weeks in culture. The labeled GAG secreted by cultured corneas was identified as keratan sulfate, galactosaminoglycan, and heparan sulfate. Corneal GAG labeled in vivo consisted primarily of keratan sulfate and galactosaminoglyca...