Embryonic Stem Cell Extracts Possess Immune Modulatory Properties That Prevent Dendritic Cell Maturation and T Cell Activation

Embryonic stem cells (ESC) possess immune privileged properties and have the capacity to modulate immune activation. ESCs can persist across allogeneic immunological barriers, prevent lymphocyte proliferation in mixed lymphocyte reaction (MLR) assays and can promote graft acceptance. However, clinic...

Full description

Bibliographic Details
Main Author: Mohib, Kanishka
Other Authors: Wang, Lisheng
Language:en
Published: Université d'Ottawa / University of Ottawa 2012
Subjects:
Online Access:http://hdl.handle.net/10393/22794
http://dx.doi.org/10.20381/ruor-5660
id ndltd-uottawa.ca-oai-ruor.uottawa.ca-10393-22794
record_format oai_dc
spelling ndltd-uottawa.ca-oai-ruor.uottawa.ca-10393-227942018-01-05T19:01:14Z Embryonic Stem Cell Extracts Possess Immune Modulatory Properties That Prevent Dendritic Cell Maturation and T Cell Activation Mohib, Kanishka Wang, Lisheng Embryonic stem cell Dendritic cells T cells Immune modulation Embryonic stem cells (ESC) possess immune privileged properties and have the capacity to modulate immune activation. ESCs can persist across allogeneic immunological barriers, prevent lymphocyte proliferation in mixed lymphocyte reaction (MLR) assays and can promote graft acceptance. However, clinical application of live ESC to treat immunological disorders is not feasible as live ESC can form teratoma in-vivo. In order to harness these properties of ESCs without adverse risk to patients, we hypothesized that ESC derived extracts may retain immune modulatory properties of whole cells and therefore could be used to abrogate allo-immune responses. We found addition of ESC-extracts from human lines H1 and H9, significantly prevented T cell proliferation in allogeneic MLRs. These results were confirmed using murine J1 ESC line. In-vitro studies showed human ESC EXT were able to modulate maturation of human monocyte derived dendritic cells (DC) by suppressing up-regulation of important co-stimulatory and maturation markers CD80, HLA-DR and CD83. In addition, DCs educated in the presence of human ESC extracts significantly lost their ability to stimulate purified allogeneic T cells compared to control extract treated DCs. We also determined that ESC extracts have an independent effect on T cells. ESC extracts prevented T cell proliferation in response to anti CD3/CD28 stimulation. In MLRs, ESC derived factors significantly down-regulated IL-2 and IFN-γ expression, while up-regulating TGF-β and Foxp3 expression. Furthermore, lymphocytes and purified T cells activated with anti-CD3/CD28, ConA and PMA proliferated poorly in the presence of ESC derived factors, while proliferation in response to ionomycin was not affected. Western blot analysis indicated that ESC derived factors prevented PKC-θ phosphorylation without influencing total PKC-θ levels. Moreover, IκB-α degradation was abrogated, confirming absence of PKC-θ activity. Therefore, ESC extracts have potent immune suppressive properties and may have clinical applications in ameliorating transplant rejection and autoimmune conditions. 2012-04-26T12:49:09Z 2012-04-26T12:49:09Z 2012 2012 Thesis http://hdl.handle.net/10393/22794 http://dx.doi.org/10.20381/ruor-5660 en Université d'Ottawa / University of Ottawa
collection NDLTD
language en
sources NDLTD
topic Embryonic stem cell
Dendritic cells
T cells
Immune modulation
spellingShingle Embryonic stem cell
Dendritic cells
T cells
Immune modulation
Mohib, Kanishka
Embryonic Stem Cell Extracts Possess Immune Modulatory Properties That Prevent Dendritic Cell Maturation and T Cell Activation
description Embryonic stem cells (ESC) possess immune privileged properties and have the capacity to modulate immune activation. ESCs can persist across allogeneic immunological barriers, prevent lymphocyte proliferation in mixed lymphocyte reaction (MLR) assays and can promote graft acceptance. However, clinical application of live ESC to treat immunological disorders is not feasible as live ESC can form teratoma in-vivo. In order to harness these properties of ESCs without adverse risk to patients, we hypothesized that ESC derived extracts may retain immune modulatory properties of whole cells and therefore could be used to abrogate allo-immune responses. We found addition of ESC-extracts from human lines H1 and H9, significantly prevented T cell proliferation in allogeneic MLRs. These results were confirmed using murine J1 ESC line. In-vitro studies showed human ESC EXT were able to modulate maturation of human monocyte derived dendritic cells (DC) by suppressing up-regulation of important co-stimulatory and maturation markers CD80, HLA-DR and CD83. In addition, DCs educated in the presence of human ESC extracts significantly lost their ability to stimulate purified allogeneic T cells compared to control extract treated DCs. We also determined that ESC extracts have an independent effect on T cells. ESC extracts prevented T cell proliferation in response to anti CD3/CD28 stimulation. In MLRs, ESC derived factors significantly down-regulated IL-2 and IFN-γ expression, while up-regulating TGF-β and Foxp3 expression. Furthermore, lymphocytes and purified T cells activated with anti-CD3/CD28, ConA and PMA proliferated poorly in the presence of ESC derived factors, while proliferation in response to ionomycin was not affected. Western blot analysis indicated that ESC derived factors prevented PKC-θ phosphorylation without influencing total PKC-θ levels. Moreover, IκB-α degradation was abrogated, confirming absence of PKC-θ activity. Therefore, ESC extracts have potent immune suppressive properties and may have clinical applications in ameliorating transplant rejection and autoimmune conditions.
author2 Wang, Lisheng
author_facet Wang, Lisheng
Mohib, Kanishka
author Mohib, Kanishka
author_sort Mohib, Kanishka
title Embryonic Stem Cell Extracts Possess Immune Modulatory Properties That Prevent Dendritic Cell Maturation and T Cell Activation
title_short Embryonic Stem Cell Extracts Possess Immune Modulatory Properties That Prevent Dendritic Cell Maturation and T Cell Activation
title_full Embryonic Stem Cell Extracts Possess Immune Modulatory Properties That Prevent Dendritic Cell Maturation and T Cell Activation
title_fullStr Embryonic Stem Cell Extracts Possess Immune Modulatory Properties That Prevent Dendritic Cell Maturation and T Cell Activation
title_full_unstemmed Embryonic Stem Cell Extracts Possess Immune Modulatory Properties That Prevent Dendritic Cell Maturation and T Cell Activation
title_sort embryonic stem cell extracts possess immune modulatory properties that prevent dendritic cell maturation and t cell activation
publisher Université d'Ottawa / University of Ottawa
publishDate 2012
url http://hdl.handle.net/10393/22794
http://dx.doi.org/10.20381/ruor-5660
work_keys_str_mv AT mohibkanishka embryonicstemcellextractspossessimmunemodulatorypropertiesthatpreventdendriticcellmaturationandtcellactivation
_version_ 1718597516947095552