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Volume 8 Journal of Stem Cell Research & Therapy
ISSN: 2157-7633 Stem Cell Congress 2018
October 08-09, 2018
October 08-09, 2018 | Zurich, Switzerland
10 th Annual Conference on
Stem Cell & Regenerative Medicine
EffectofmesenchymalstromalcellsonTcellsinasepticcontext:Immunosuppressionorimmunostimulation?
Juliette Peltzer1, Sebastien Le Burel1, Cedric Thepenier1, Laetitia Boutin2, and Jean-Jacques Lataillade1,2
1Biomedical Research Institute of the Armed Forces, France
2University Hospital of South Paris, France
S epsis is a complex process, including a first wave of damage partially due to the body’s response to pathogens, followed by
a phase of immune cell dysfunction. The efficacy of a pharmacological approach facing a rapidly evolving system implies
a perfect timing of administration, this difficulty could explain the recent failure of clinical trials. Mesenchymal stromal cells
(MSCs) are usually defined as immunosuppressive and their beneficial effects in preclinical models of acute sepsis have been
shown to rely partly on such ability. If nonregulated, this phenotype could be harmful in the immunosuppressed context
arising hours after sepsis onset. However, MSCs being environment sensitive, we hypothesized that they could reverse their
immunosuppressive properties when confronted with suffering immune cells. Our objective was to evaluate the effect of human
MSCs on activated human lymphocytes in an in vitro endotoxemia model. Peripheral blood mononuclear cells (PBMCs)
underwent a 24-h lipopolysaccharide (LPS) intoxication and were stimulated with phytohemagglutinin (PHA) in contact
with MSCs. MSCs induced a differential effect on lymphocytes depending on PBMC intoxication with LPS. Unintoxicated
lymphocytes were highly proliferative with PHA and were inhibited by MSCs, whereas LPS-intoxicated lymphocytes showed
a low proliferation rate, but were supported by MSCs, even when monocytes were depleted. These data, highlighting MSC
plasticity in their immunomodulatory activity, pave the way for further studies investigating the mechanisms of mutual
interactions between MSCs and immune cells in sepsis. Thus, MSCs might be able to fight against both early sepsis-induced
hyper-inflammatory response and later time points of immune dysfunction.
Biography
Juliette Peltzer research aims to understand the coordinated relationships between metabolic and contractile pathways occurring during the differentiation of
muscle satellite cells. In 2008, she joined Prof. Lataillade’s laboratory specialized in cell therapy using mesenchymal stromal cells in different contexts and
especially in humans in the case of radiation burns. She was first in charge of the characterization of perinatal MSCs, which we believe to be a good candidate for
allogeneic cell therapy. Then they started to work on septic shock requiring extremely short processing times and therefore the use of immediately available cells
from allogenic banking.
Juliette Peltzer et al., J Stem Cell Res Ther 2018, Volume 8
DOI: 10.4172/2157-7633-C4-041