Cell Binding

Table I describes several of the fluorescent assays that have been used in our lab to study neutrophil activation. Fluorescein-labeled W-formylhexapeptide (FLPEP) has been used to characterize the ki- netics of ligand binding, dissociation, and internalization at 37°C (7,8). FLPEP is added to a suspension of cells, then receptor-bound and free FLPEP in solution are distinguished by adding antibody to fluorescein. This is a high-affinity antibody which binds free FLPEP within 1 s hut does not bind cell-bound FLPEP. When it binds the FLPEP, it quenches the fluorescein fluorescence. Hence the residual fluorescence after antibody addition represents FLPEP that is bound to the cell. Nonspecific binding is determined in cell suspensions that contain an excess of nonfluorescent peptide.

Leyton, L., and Saling, P. (1989). 95 kd sperm proteins bind ZP3 and serve as tyrosine kinase substrates in response to zona binding. Cell 57 1123-1130. 

Shi, Y., A conserved tetrapeptide motif potentiating apoptosis through lAP-binding. Cell Death Differ, 2002, 9(2), 93-5. 

Some new materials perspective for advanced biomedical technologies, especially carbon nanoparticles like fullerenes, are potentially mutagenic, carcinogenic and immunogenic [16,65], Therefore, standard tests of the morphological transformation of Syrian hamster embryonic cells in cultures on these materials (described in detail by [68,69]) can be performed. Immune activation of bone and vascular cells on the materials can be estimated by increased concentration of immunoglobulin and selectin adhesion molecules (ICAM-1, VCAM-1, ELAM-1), which bind cells of the immune system [15,16,18,19,23], as well as by the production of cytokines, such as tumor necrosis factor alpha or interleukins beta [55],... 

Fig. 11. Flow cytometric detection of apoptotic cell deadi using the annexin V method after treatment with IgM anti-Fas mAb. The vacant retrovirus vector (LXSN)-transfected Jurkat cell clone of LX-2 clearly exhibits annexin V binding at 3 h after treatment (56.8%), and the binding cell population is further increased at 5 h (77.2%), whereas only faint annexin V binding is observed in LdelSN-transfected Jurkat cell clone RJ-14. This means diat endogenous wild-type mFas in the LX-2 cells is functional in Fas-mediated apoptosis, but transfected aberrant mFas in die RJ-14 cells interferes with die signaUng in a dominant negative manner.

Vitamin C (ascorbic acid) is essential for the maintenance of the ground substance that binds cells together and for the formation and maintenance of collagen. The exact biochemical role it plays in these functions is not known, but it may be related to its ability to act as an oxidation-reduction system. 

Sanchez, C. and Hyttel, J. (1999) Comparison of the effects of antidepressants and their metabolites on reuptake of biogenic amines and on receptor binding. Cell Mol Neurobiol 19 467-489. 

Pierschbacher and Ruoslahti [130] in 1984 reported that the ability of fibronec-tin to bind cells can be accounted for by the tetrapeptide L-arginyl-glycyl-L-aspartyl-L-serine (RGDS), a sequence which is part of the cell attachment domain of fibronectin. They examined the cell-attachment activity of several... 

Amphotericin B Cholesteryl (Amphotec) [Anrifungal/Polyene Macrolide] Uses Aspergillosis if intolerant/reffactory to conventional amphotericin B, systemic candidiasis Action Binds cell membrane sterols, alters permeability Dose Adults Peds. Test dose 1.6—8.3 mg, over 15—20 min, then 3-4 mg/kg/d 1 mg/kg/h inf X w/ renal insuff Caution [B, ] Disp Inj SE Anaphylaxis fever, chills, HA, nephrotox, X BP, anemia Notes Do not use in-line filter Interactions See Amphotericin B EMS See Amphotericin B OD May cause cardiac arrest symptomatic and supportive... 

Gimona, M., and Mital, R. (1998). The single CH domain of calponin is neither sufficient nor necessary for F-actin binding./. Cell Sci. Ill, 1813-1821. 

Pectin is a polysaccharide found in the nonwoody cell walls of plants where it binds cells together and helps the plant take in water. In fruits, it is broken down during the ripening process, and this is why ripe fruits are soft. The fruits that contain the most pectin are apples, plums, grapefruits, and oranges. Pectin is commonly used as a food additive, especially as a thickener for jams and marmalades, where it provides the jellylike consistency. 

In the extracellular matix, fibronectin serves as the matrix organizer. This is still poorly understood, but it is known that fibronectin can interact with proteoglycans, collagens, and cells enmeshed in the matrix, where it binds cells together and anchors them to the matrix. This function also follows fibronectin to act as a mediator of cell growth and differentiation. In some cell systems such as the epithelial cells, this function is replaced by another tissue glycoprotein, laminin. 

Xie, T., and Tsong, T.Y. (1993) Study of mechanisms of electric field-induced DNA transfection. V. Effects of DNA topology on surface binding, cell uptake, expression and integration into host chromosomes of DNA in the mammalian cell. BiophysJ. 65 1684-1689. 

Figure 9.7 Evaluation of biopharmaceutical X binding to mouse bone marrow derived cells, (a) Biopharmaceutical X binding to mouse bone marrow-derived cells was evaluated using flow cytometry. Mouse cells were incubated with biopharmaceutical X or the human ligand. Secondary antibodies that cross-reacted with both biopharmaceutical X and the natural human ligand were used to detect binding. Cells were stained with the secondary antibodies only, to detect non-specific binding (control), (b) Bone marrow derived mouse cells were stained as described above with a murine version of biopharmaceutical X and the murine ligand for the receptor. Secondary antibodies that cross-reacted with the murine version of biopharmaceutical X and the murine ligand were used to detect binding. See color insert.

Ligand-receptor binding (cell-based or mem brane-basedj e.g., ligand induced GTPyS binding... 

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