title: Finding and tracing human MSC in 3D microenvironments with the photoconvertible protein Dendra2.
abstract: Mesenchymal Stem/Stromal Cells (MSC) are a promising cell type for cell-based therapies - from tissue regeneration to treatment of autoimmune diseases - due to their capacity to migrate to damaged tissues, to differentiate in different lineages and to their immunomodulatory and paracrine properties. Here, a simple and reliable imaging technique was developed to study MSC dynamical behavior in natural and bioengineered 3D matrices. Human MSC were transfected to express a fluorescent photoswitchable protein, Dendra2, which was used to highlight and follow the same group of cells for more than seven days, even if removed from the microscope to the incubator. This strategy provided reliable tracking in 3D microenvironments with different properties, including the hydrogels Matrigel and alginate as well as chitosan porous scaffolds. Comparison of cells mobility within matrices with tuned physicochemical properties revealed that MSC embedded in Matrigel migrated 64% more with 5.2 mg protein/mL than with 9.6 mg/mL and that MSC embedded in RGD-alginate migrated 51% faster with 1% polymer concentration than in 2% RGD-alginate. This platform thus provides a straightforward approach to characterize MSC dynamics in 3D and has applications in the field of stem cell biology and for the development of biomaterials for tissue regeneration.
authors.affiliation: 1] Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal [2] INEB - Instituto de Engenharia Biomédica, Universidade do Porto, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal [3] ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
authors.forename: Hugo R
authors.initials: HR
authors.lastname: Caires
authors.affiliation: 1] Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal [2] INEB - Instituto de Engenharia Biomédica, Universidade do Porto, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal [3] b.IMAGE - Bioimaging Center for Biomaterials and Regenerative Therapies, INEB, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal.
authors.forename: Maria
authors.initials: M
authors.lastname: Gomez-Lazaro
authors.affiliation: 1] Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal [2] INEB - Instituto de Engenharia Biomédica, Universidade do Porto, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal [3] ISPUP - Instituto de Saúde Pública da Universidade do Porto, Rua das Taipas, 135, 4050-600 Porto, Portugal.
authors.forename: Carla M
authors.initials: CM
authors.lastname: Oliveira
authors.affiliation: 1] Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal [2] INEB - Instituto de Engenharia Biomédica, Universidade do Porto, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal.
authors.forename: David
authors.initials: D
authors.lastname: Gomes
authors.affiliation: 1] Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal [2] IPATIMUP - Instituto de Patologia e Imunologia Molecular da Universidade do Porto, Rua Dr. Roberto Frias s/n, 4200-465 Porto, Portugal.
authors.forename: Denisa D
authors.initials: DD
authors.lastname: Mateus
authors.affiliation: 1] Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal [2] IPATIMUP - Instituto de Patologia e Imunologia Molecular da Universidade do Porto, Rua Dr. Roberto Frias s/n, 4200-465 Porto, Portugal [3] Medical Faculty of the University of Porto, Alameda Hernani Monteiro, 4200-319 Porto, Portugal.
authors.forename: Carla
authors.initials: C
authors.lastname: Oliveira
authors.affiliation: 1] Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal [2] INEB - Instituto de Engenharia Biomédica, Universidade do Porto, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal.
authors.forename: Cristina C
authors.initials: CC
authors.lastname: Barrias
authors.affiliation: 1] Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal [2] INEB - Instituto de Engenharia Biomédica, Universidade do Porto, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal [3] ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
authors.forename: Mário A
authors.initials: MA
authors.lastname: Barbosa
authors.affiliation: 1] Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal [2] INEB - Instituto de Engenharia Biomédica, Universidade do Porto, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal.
authors.forename: Catarina R
authors.initials: CR
authors.lastname: Almeida
mesh_terms: D001672:Biocompatible Materials; D057005:Bioengineering; D015415:Biomarkers; D001854:Bone Marrow Cells / Q000166:cytology; D002465:Cell Movement / Q000502:physiology*; D002470:Cell Survival; D058948:Cell Tracking / Q000379:methods*; D002478:Cells, Cultured; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008164:Luminescent Proteins / Q000235:genetics*; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D054457:Tissue Scaffolds; D014162:Transfection; D014945:Wound Healing / Q000502:physiology
chemical_list: D001672:Biocompatible Materials; D015415:Biomarkers; C583169:Dendra2 protein, Dendronephthya; D008164:Luminescent Proteins