Cell culture

About: Cell culture is a research topic. Over the lifetime, 133361 publications have been published within this topic receiving 5364150 citations. The topic is also known as: cell culture techniques.

Role of laminin and basement membrane in the morphological differentiation of human endothelial cells into capillary-like structures.

Abstract: We have defined a signal responsible for the morphological differentiation of human umbilical vein and human dermal microvascular endothelial cells in vitro. We find that human umbilical vein endothelial cells deprived of growth factors undergo morphological differentiation with tube formation after 6-12 wk, and that human dermal microvascular endothelial cells differentiate after 1 wk of growth factor deprivation. Here, we report that morphological differentiation of both types of endothelial cells is markedly accelerated by culture on a reconstituted gel composed of basement membrane proteins. Under these conditions, tube formation begins in 1-2 h and is complete by 24 h. The tubes are maintained for greater than 2 wk. Little or no proliferation occurs under these conditions, although the cells, when trypsinized and replated on fibronectin-coated tissue culture dishes, resume division. Ultrastructurally, the tubes possess a lumen surrounded by endothelial cells attached to one another by junctional complexes. The cells possess Weibel-Palade bodies and factor VIII-related antigens, and take up acetylated low density lipoproteins. Tubule formation does not occur on tissue culture plastic coated with laminin or collagen IV, either alone or in combination, or on an agarose or a collagen I gel. However, endothelial cells cultured on a collagen I gel supplemented with laminin form tubules, while supplementation with collagen IV induces a lesser degree of tubule formation. Preincubation of endothelial cells with antibodies to laminin prevented tubule formation while antibodies to collagen IV were less inhibitory. Preincubation of endothelial cells with synthetic peptides derived from the laminin B1 chain that bind to the laminin cell surface receptor or incorporation of these peptides into the gel matrix blocked tubule formation, whereas control peptides did not. These observations indicate that endothelial cells can rapidly differentiate on a basement membrane-like matrix and that laminin is the principal factor in inducing this change.

Direct Recognition of Cytomegalovirus by Activating and Inhibitory NK Cell Receptors

Abstract: Natural killer (NK) cells express inhibitory receptors for major histocompatibility complex (MHC) class I antigens, preventing attack against healthy cells Mouse cytomegalovirus (MCMV) encodes an MHC-like protein (m157) that binds to an inhibitory NK cell receptor in certain MCMV-susceptible mice In MCMV-resistant mice, this viral protein engages a related activating receptor (Ly49H) and confers host protection These activating and inhibitory receptors are highly homologous, suggesting the possibility that one evolved from the other in response to selective pressure imposed by the pathogen

Tobacco BY-2 Cell Line as the “HeLa” Cell in the Cell Biology of Higher Plants

Abstract: Publisher Summary This chapter highlights tobacco BY-2 (TBY-2) cell line. TBY-2 derived from the seedlings of N. tabacum L. cv. Bright Yellow 2 grows fast and multiplies 80- to 100-fold in 1 week. After the stationary phase, cells of TBY-2 are transferred to a medium containing aphidicolin for 24 hr and then released from treatment; high synchrony is obtained starting from the S phase. TBY-2 cells are propagated in the modified medium of Linsmaier and Skoog, in which KH2PO4 and thiamine HCl are increased to 370 and 1 mg/liter, respectively, and sucrose and 2,4-D are supplemented to 3% and 0.2 mg/liter, respectively. The preparation of protoplasts from TBY-2 cells, from which the isolation of organelles is easy, has been established. Using the synchrony system, the change in the cell cycle progression of TBY-2 cells successfully followed the change in cytoskeletons. Biochemical and molecular biological studies can also be done on TBY-2 cells, as mass culture of this material is readily feasible.

Caspase-dependent immunogenicity of doxorubicin-induced tumor cell death.

Abstract: Systemic anticancer chemotherapy is immunosuppressive and mostly induces nonimmunogenic tumor cell death. Here, we show that even in the absence of any adjuvant, tumor cells dying in response to anthracyclins can elicit an effective antitumor immune response that suppresses the growth of inoculated tumors or leads to the regression of established neoplasia. Although both antracyclins and mitomycin C induced apoptosis with caspase activation, only anthracyclin-induced immunogenic cell death was immunogenic. Caspase inhibition by Z-VAD-fmk or transfection with the baculovirus inhibitor p35 did not inhibit doxorubicin (DX)-induced cell death, yet suppressed the immunogenicity of dying tumor cells in several rodent models of neoplasia. Depletion of dendritic cells (DCs) or CD8 + T cells abolished the immune response against DX-treated apoptotic tumor cells in vivo. Caspase inhibition suppressed the capacity of DX-killed cells to be phagocytosed by DCs, yet had no effect on their capacity to elicit DC maturation. Freshly excised tumors became immunogenic upon DX treatment in vitro, and intratumoral inoculation of DX could trigger the regression of established tumors in immunocompetent mice. These results delineate a procedure for the generation of cancer vaccines and the stimulation of anti-neoplastic immune responses in vivo.