Matrix stiffness determines the fate of nucleus pulposus-derived stem cells.
Intervertebral disc (IVD) degeneration and consequent low-back pain present a major medical challenge. Nucleus pulposus-derived stem cells (NP-SCs) may lead to a novel therapy for this severe disease. It was recently shown that survival and function of mature NP cells are regulated in part by tissue stiffness. We hypothesized that modification of matrix stiffness will influence the ability of cultured NP-SCs to proliferate, survive, and differentiate into mature NP cells. NP-SCs were subcultured in three-dimensional matrices of varying degrees of stiffness as measured by the material's shear storage modulus. Cell survival, activity, and rate of differentiation toward the chondrogenic or osteogenic lineage were analyzed. NP-SCs were found to proliferate and differentiate in all matrices, irrespective of matrix stiffness. However, matrices with a low shear storage modulus (G' = 1 kPa) promoted significantly more proliferation and chondrogenic differentiation, whereas matrices with a high modulus (G' = 2 kPa) promoted osteogenic differentiation. Imaging performed via confocal and scanning electron microscopes validated cell survival and highlighted stiffness-dependent cell-matrix interactions. These results underscore the effect of the matrix modulus on the fate of NP-SCs. This research may facilitate elucidation of the complex cross-talk between NP-SCs and their surrounding matrix in healthy as well as pathological conditions.
Skeletal Biotech Laboratory, The Hebrew University-Hadassah Faculty of Dental Medicine, Ein Kerem, Jerusalem 91120, Israel.
Yosi
Y
Navaro
Skeletal Biotech Laboratory, The Hebrew University-Hadassah Faculty of Dental Medicine, Ein Kerem, Jerusalem 91120, Israel.
Nadav
N
Bleich-Kimelman
Department of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.
Lena
L
Hazanov
Department of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.
Iris
I
Mironi-Harpaz
Department of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.
Yonatan
Y
Shachaf
Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel; Max Planck Institute for Intelligent Systems, Stuttgart, Germany.
Shai
S
Garty
Genomic Data Analysis Unit, The Hebrew University-Hadassah Medical School, The Hebrew University of Jerusalem, Jerusalem 91120, Israel.
Yoav
Y
Smith
Skeletal Biotech Laboratory, The Hebrew University-Hadassah Faculty of Dental Medicine, Ein Kerem, Jerusalem 91120, Israel; Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA; Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA.
Gadi
G
Pelled
Skeletal Biotech Laboratory, The Hebrew University-Hadassah Faculty of Dental Medicine, Ein Kerem, Jerusalem 91120, Israel; Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA; Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA.
Dan
D
Gazit
Department of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.
Dror
D
Seliktar
Skeletal Biotech Laboratory, The Hebrew University-Hadassah Faculty of Dental Medicine, Ein Kerem, Jerusalem 91120, Israel; Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA; Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA. Electronic address: zulmag@ekmd.huji.ac.il.
Zulma
Z
Gazit
D000818:Animals; D001696:Biomechanical Phenomena / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D019070:Cell Lineage / Q000187:drug effects; D048430:Cell Shape / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D021982:Cell-Matrix Junctions / Q000187:drug effects / Q000378:metabolism; D002478:Cells, Cultured; D020219:Chondrogenesis / Q000187:drug effects; D055119:Elastic Modulus / Q000187:drug effects; D005029:Ethylenediamines / Q000494:pharmacology; D005109:Extracellular Matrix / Q000187:drug effects / Q000502:physiology*; D020100:Hydrogels / Q000494:pharmacology; D007403:Intervertebral Disc / Q000166:cytology*; D012212:Rheology / Q000187:drug effects; D013234:Stem Cells / Q000166:cytology*; D034421:Sus scrofa
D005029:Ethylenediamines; D020100:Hydrogels
Elasticity; Fibrinogen; Hydrogel; Intervertebral disc; Matrix stiffness; Stem cells