Evidence for a novel cell isolation system for high affinity catch and release of adSCs from minimally processed adult tissue. This system utilises large, dense separation beads populated with an Title Loaded From File antibody binding ligand. The Title Loaded From File ligand binds cell-specific antibody in a pH dependent manner permitting simple cell release with a small shift in reaction pH. Herein this system was utilised to isolate and release adSCs from rat adipose SVF.Materials and Methods Ethics statementAll studies adhered to UK home office use of animals in scientific procedures guidelines and were approved by the Institutional Review Board of the University of Liverpool.Isolation of stromal vascular fraction (SVF) from rat adipose tissueSubcutaneous and visceral adipose were dissected from adult Wister rats. Primary tissue was washed 3x using PBS, coarsely macerated using sterile dissection scissors and liquidised by forcing through a 10 ml syringe. Digestion was achieved by incubation in 0.2 collagenase/PBS (Sigma-Aldrich, UK) (37uC, 90 mins, 50 v/v collagenase solution/tissue homogenate). After this time had elapsed the reaction was neutralised by addition of 10 fetal calf serum. The digest was passed through a 100 mm cell strainer then centrifuged (400 g, 10 mins). To remove residual erythrocytes, cells were suspended in 200 ml PBS with 1 ml Optilyse C (Beckman Coulter, RT, 10 mins). 10 ml PBS was then added to the erythrolysed cell suspension before a final centrifugation to recover SVF cells (400 g 10 mins). Resulting cells were suspended in an appropriate volume of PBS and numerated using a hemocytometer.Immunofluorescent staining and FACS analysisSVF was labelled with FITC conjugated mouse anti rat CD90, CD29, CD44, CD45, and CD31 (15 mins, 4uC, 1 mg antibody/ 105 cells). A FITC conjugated isotype control (IgG1) was used at the same concentration to allow post-hoc subtraction of nonantigen-specific fluorescence. The percentage cells in the SVF fraction expressing these antigens was quantified using flow cytometry to numerate cells with associated antibody mediated fluorescence.CD90+ isolation: protein A-coated beads (non-reversible antibody binding)CD90+ cell capture was achieved by labelling cells and loading Protein A-coated capture beads (50?00 mm diameter, CellCap Technologies Ltd) with CD90 antibody at the following concentrations: 1 mg antibody/105 cells and 1 mg antibody/10 mL beads. Equal volumes of cell suspensions and beads were incubated in a final volume of 1 ml PBS with gentle rolling in 1.5 ml polypropylene tubes on a roller table (30 mins, 4uC). Reactions in which neither cells nor beads received antibody were performed as a negative control. Post bead/cell interaction, the percentage of cells specifically depleted by specific capture was quantified using flow cytometry, again based on cellular events associated with antibody mediated FITC fluorescence.RNA isolationThe following solutions were prepared prior to RNA isolation (all reagents Qiagen, UK unless stated otherwise). 44 ml of ACS grade 100 ethanol was added to 6 ml wash buffer (RPE), while 10 ml of 1 M b-mercaptoethanol (Sigma-Aldrich UK) was added to 1 ml lysis buffer (RLT). Prior to RNA extraction cells were washed with PBS (365 minutes, room temperature). Following this, 350 ml of buffer RLT was added to each sample and incubated for 5 minutes at room temperature. Resulting lysates were transferred to QIAshredder columns and spun at 13400 g for 2 minutes. 250 ml of 100 ethanol was ad.Evidence for a novel cell isolation system for high affinity catch and release of adSCs from minimally processed adult tissue. This system utilises large, dense separation beads populated with an antibody binding ligand. The ligand binds cell-specific antibody in a pH dependent manner permitting simple cell release with a small shift in reaction pH. Herein this system was utilised to isolate and release adSCs from rat adipose SVF.Materials and Methods Ethics statementAll studies adhered to UK home office use of animals in scientific procedures guidelines and were approved by the Institutional Review Board of the University of Liverpool.Isolation of stromal vascular fraction (SVF) from rat adipose tissueSubcutaneous and visceral adipose were dissected from adult Wister rats. Primary tissue was washed 3x using PBS, coarsely macerated using sterile dissection scissors and liquidised by forcing through a 10 ml syringe. Digestion was achieved by incubation in 0.2 collagenase/PBS (Sigma-Aldrich, UK) (37uC, 90 mins, 50 v/v collagenase solution/tissue homogenate). After this time had elapsed the reaction was neutralised by addition of 10 fetal calf serum. The digest was passed through a 100 mm cell strainer then centrifuged (400 g, 10 mins). To remove residual erythrocytes, cells were suspended in 200 ml PBS with 1 ml Optilyse C (Beckman Coulter, RT, 10 mins). 10 ml PBS was then added to the erythrolysed cell suspension before a final centrifugation to recover SVF cells (400 g 10 mins). Resulting cells were suspended in an appropriate volume of PBS and numerated using a hemocytometer.Immunofluorescent staining and FACS analysisSVF was labelled with FITC conjugated mouse anti rat CD90, CD29, CD44, CD45, and CD31 (15 mins, 4uC, 1 mg antibody/ 105 cells). A FITC conjugated isotype control (IgG1) was used at the same concentration to allow post-hoc subtraction of nonantigen-specific fluorescence. The percentage cells in the SVF fraction expressing these antigens was quantified using flow cytometry to numerate cells with associated antibody mediated fluorescence.CD90+ isolation: protein A-coated beads (non-reversible antibody binding)CD90+ cell capture was achieved by labelling cells and loading Protein A-coated capture beads (50?00 mm diameter, CellCap Technologies Ltd) with CD90 antibody at the following concentrations: 1 mg antibody/105 cells and 1 mg antibody/10 mL beads. Equal volumes of cell suspensions and beads were incubated in a final volume of 1 ml PBS with gentle rolling in 1.5 ml polypropylene tubes on a roller table (30 mins, 4uC). Reactions in which neither cells nor beads received antibody were performed as a negative control. Post bead/cell interaction, the percentage of cells specifically depleted by specific capture was quantified using flow cytometry, again based on cellular events associated with antibody mediated FITC fluorescence.RNA isolationThe following solutions were prepared prior to RNA isolation (all reagents Qiagen, UK unless stated otherwise). 44 ml of ACS grade 100 ethanol was added to 6 ml wash buffer (RPE), while 10 ml of 1 M b-mercaptoethanol (Sigma-Aldrich UK) was added to 1 ml lysis buffer (RLT). Prior to RNA extraction cells were washed with PBS (365 minutes, room temperature). Following this, 350 ml of buffer RLT was added to each sample and incubated for 5 minutes at room temperature. Resulting lysates were transferred to QIAshredder columns and spun at 13400 g for 2 minutes. 250 ml of 100 ethanol was ad.
