human soluble recombinant psgl1  (R&D Systems)

Journal: Pharmaceutical Research

Article Title: Targeting of Liposomes via PSGL1 for Enhanced Tumor Accumulation

doi: 10.1007/s11095-012-0875-5

Figure Lengend Snippet: Production of a protein G-streptavidin conjugate for linkage of immunoglobulin G Fc containing ligands to liposomes. ( a ) Outline of the strategy for the linkage of liposomes presenting PEG-biotin to the targeting ligand PSGL1-Fc via a linker comprised of streptavidin (for biotin binding) and protein G (for Fc binding). ( b ) Coomassie stained SDSPAGE of protein G-streptavidin conjugates formed at ratios of; lane 1 = 3 streptavidin : 1 protein G, lane 2 = 1 streptavidin : 4 protein G, lane 3 = free protein G in reaction buffers, lane 4 = free protein G direct from stock. ( c ) Probing of nitrocellulose with biotin-HRP; lane 1 = 3 streptavidin : 1 protein G, lane 2 = 1 streptavidin : 4 protein G, lane 3 = free protein G in reaction buffers. ( d ) Probing of nitrocellulose with Fc-HRP; lane 1 = 3 streptavidin : 1 protein G, lane 2 = 1 streptavidin : 4 protein G, lane 3 = free protein G in reaction buffers.

Article Snippet: Fc linked PSGL1 (3345-PS) and the control Fc lacking the PSGL1 domain (110-HG) were purchased from R and D Systems (UK).

Techniques: Liposomes, Binding Assay, Staining

Journal: Pharmaceutical Research

Article Title: Targeting of Liposomes via PSGL1 for Enhanced Tumor Accumulation

doi: 10.1007/s11095-012-0875-5

Figure Lengend Snippet: The influence of PSGL1 addition on the physicochemical and biological activity of liposomes. ( a ) Dynamic light scattering analysis of the size and polydispersity of liposomes or modified liposomes. ( b ) Ability of Fc-control or PSGL1 liposomes to adhere to E-selectin coated plates, as measured by detection of luminescence in wells after incubation with luciferin loaded liposomes, washing, rupture of liposomes and luciferase enzyme addition. N = 3, SD shown, significance ( p < 0.05) calculated by ANOVA. ( c ) Ability of liposomes to adhere to / deliver luciferin to HUVECs expressing the luciferase enzyme, as assayed after incubation with luciferin loaded liposomes, washing, and multiple subsequent luminescence measurements. Black line and diamonds = unmodified liposomes, blue line and squares = Fc control liposomes, red line and triangles = PSGL1 liposomes. N = 4, standard error (se) shown, significance ( p < 0.001) calculated by ANOVA with Tukey post test all samples comparison using PRISM.

Article Snippet: Fc linked PSGL1 (3345-PS) and the control Fc lacking the PSGL1 domain (110-HG) were purchased from R and D Systems (UK).

Techniques: Activity Assay, Liposomes, Modification, Control, Incubation, Luciferase, Expressing, Comparison

Journal: Pharmaceutical Research

Article Title: Targeting of Liposomes via PSGL1 for Enhanced Tumor Accumulation

doi: 10.1007/s11095-012-0875-5

Figure Lengend Snippet: Pharmacokinetics and organ and tumor accumulation of liposomes following intravenous delivery to mice bearing B16-F10-luciferase tumors. ( a ) Blood samples collected at 5, 10, 30, 60, 90 and 120 minutes were analysed for luciferin content by heating followed by luciferase enzyme addition and luminometry. Black line and diamonds = unmodified liposomes ( n = 3), blue line and squares = Fc control liposomes ( n = 5), red line and triangles = PSG1 liposomes ( n = 4), se shown, no significant differences at 120 min were evident as calculated by ANOVA. ( b ) Liposome accumulation in specified organs was quantified at 120 min post injection by homogenising organs heating, adding luciferase enzyme and measuring by luminometry. Unmodified liposomes n = 3, Fc control and PSGL1 liposomes n = 5, data calculated as % of injected dose / whole organ. ( c ) Liposome accumulation in tumors was quantified at 120 min post injection by homogenising tumors, heating, adding luciferase enzyme and measuring by luminometry. Unmodified liposomes n = 3, Fc control and PSGL1 liposomes n = 5, data calculated as % of injected dose / gram of tumor (%ID/g), significant difference ( p < 0.05) evident as calculated by ANOVA with Tukey post test all samples comparison using PRISM.

Article Snippet: Fc linked PSGL1 (3345-PS) and the control Fc lacking the PSGL1 domain (110-HG) were purchased from R and D Systems (UK).

Techniques: Drug discovery, Liposomes, Luciferase, Control, Injection, Comparison