Detail of "134282-68-1"

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Monocyte/macrophage interactions with base and linear-and star-like PEG-modified PEG-poly(acrylic acid) copolymers

Monocyte/macrophage interactions with base and linear-and star-like PEG-modified PEG-poly(acrylic acid) copolymers. Wagner, Victoria E.Several substances are used for example 134282-68-1 and 25322-68-3 which are their cas registry numbers.; Bryers, James D. (The Department of Chemical Engineering, University of Connecticut, Storrs, CT 06269, USA). Journal of Biomedical Materials Research, Part A, 66A(1), 62-78 (English) 2003 John Wiley & Sons, Inc. CODEN: JBMRCH. DOCUMENT TYPE: Journal CA Section: 63 (Pharmaceuticals) Section cross-reference(s): 35 Poly(ethylene glycol)/polyacrylate (PEG-g-PA) copolymers were made that inhibited nonspecific protein and cellular adhesion. PEG-g-PA copolymers were then covalently modified with either cell adhesion peptides or fragments of antibodies to monocyte/macrophage integrin receptors (anti-VLA4, anti-b1, anti-b2, and anti-CD64) known to enhance macrophage adhesion and, perhaps, modulate their activation. Peptides were either directly conjugated to the base material or linked by way of PEO-star tethers. Fragments of the antibody region contg. the antigen-binding site (Fab' fragments) were coupled to other PEG-g-PA samples using the sulfhydryl end groups on Fab' fragments to amine-bearing PEO stars. Macrophage adhesion rates, phagocytic response (oxidative burst), and cytokine expression were detd. for each PEG-g-PA material. Luminol-enhanced chemiluminescence was used as a semi-quant. indication of monocyte-macrophage phagocytic activation (oxidative burst). Macrophage cytokine expression in response to control, base, and modified materials was detd. by ELISAs for TNF-a, IL-1b, IL-6, and IL-8. Tissue culture poly(styrene) (TCPS) mediated the greatest no. of adherent monocyte/macrophage cells relative to PEG-g-PA materials. Both YRGDS and YEILDV peptides, whether directly or indirectly (via StarPEO) conjugated to PEG-g-PA, increased adhesion vs. controls. Fab' fragments of all four antibodies also promoted enhanced adhesion vs. controls. Fab'StarPEO materials presented two orders of magnitude fewer ligands per surface unit area than peptide star materials (108 vs. 1010), but were able to adhere similar nos. of cells. For surfaces presenting Fab'VLA-4 or YEILDV, both of which may both bind to a cell's VLA-4 receptor, the Star/VLA4 surface showed a greater no. of adherent monocyte/macrophages. This result suggests that the Fab' had a higher affinity to the cell receptor than a corresponding minimal peptide binding sequence. All materials exhibited low oxidative burst (luminescence counts per min, LCPM) per cell DNA without the addn. of exogenous stimuli (LCPM/DNA < 100). Directly conjugated peptide materials, poly(propylene) (PP), and TCPS showed the lowest levels of LCPM/DNA without the addn. of exogenous stimulus (LCPM/DNA < 20). There was no correlation between LCPM/DNA ratios, with and without added LPS stimulus, vs. the individual substrates. Monocyte/macrophages adherent to TCPS substrata showed the overall highest stimulatory potential in cytokine expression response to exogenous LPS, followed by PP > PEG-g-PA > StarPEO. Cells adherent to peptide-modified materials and Fab'-modified materials were overall less stimulated. The method of presenting the peptides (i.e., directly or via Star PEO) influenced the level of cytokine secreted by the adherent macrophage. .