Crosstalk between immune cells and mesenchymal stromal cells in a 3D bioreactor system.
BACKGROUND
Mesenchymal stromal cells (MSC), known for their high immune modulatory capacity are promising tools for several cell-based therapies. To better mimic the in vivo situation of MSC interactions with immune cells, we applied an artificial lymph node (ALN)-bioreactor culture system combining a miniaturized perfusion bioreactor with a 3D matrix-based cell culture of immune competent cells forming micro-organoids.


METHODS
Rat lymph node cells and allogeneic bone marrow-derived MSCs were seeded in a 20:1 ratio within the agarose matrix of the ALN-reactor. Lymphocytes were pre-incubated with Concanavalin A (ConA) and then co-cultured with MSC in the matrix with additional ConA in the perfusing medium. Live/dead staining showed survival of the co-cultures during the 8-day ALN-reactor run. Paraffin sections of bioreactor matrices were analyzed by proliferating cell nuclear antigen (PCNA)-specific stai-ning to determine MSC proliferation. Immune modulatory capacity was defined by daily analysis of cytokine secretion profiles (TNFa, IFNy, IL-1a, IL-1ß, IL-2, IL-4, IL-6, IL-10, IL-12p40/p70, GM-CSF).


RESULTS
Cytokine peak secretion at day 2 was significantly inhibited by MSCs for TNFa (96.8 ± 4.8%) and IFNy (88.7 ± 12.0%) in 3D co-cultures. In contrast, other cytokines (IL-1, IL-6, IL-12) were induced. Furthermore, we detected a significantly higher (58.8%) fraction of proliferating MSCs in the presence of immune cells compared to control bioreactors loaded with MSCs only.


CONCLUSIONS
In the future, this system might be an excellent tool to investigate the mechanisms of MSC-mediated immune modulation during simulated in vivo conditions.
Institute of Medical Immunology, Charité-Medical University Berlin, Berlin, Germany. martina.seifert@charite.de
Martina
M
Seifert
Annika
A
Lubitz
Jeanne
J
Trommer
Darja
D
Könnig
Gabriela
G
Korus
Uwe
U
Marx
Hans-Dieter
HD
Volk
Georg
G
Duda
Grit
G
Kasper
Kerstin
K
Lehmann
Meaghan
M
Stolk
Christoph
C
Giese
D000818:Animals; D019149:Bioreactors; D002450:Cell Communication / Q000502:physiology*; D018929:Cell Culture Techniques; D049109:Cell Proliferation; D018920:Coculture Techniques; D016207:Cytokines / Q000378:metabolism; D008198:Lymph Nodes / Q000473:pathology*; D008214:Lymphocytes / Q000502:physiology*; D008297:Male; D059630:Mesenchymal Stem Cells / Q000502:physiology*; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D051381:Rats
D016207:Cytokines; D018809:Proliferating Cell Nuclear Antigen