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Immune modulation by stem cells and their derivatives

Analysis of immunogenicity and inflammatory potential of cells and biomaterials for therapy

Cell and tissue grafts could be implemented in many fields of regenerative medicine to substitute for damaged tissue and to promote the induction of self-renewing processes. Although non-foreign (autologous) cells and tissues are frequently used, several immunological problems arise by long-term culture periods in vitro as well as by their combination with matrix structures. Due to limited sources of autologous cells and a need for rapid availability, there is a substantial interest in applying foreign (allogeneic) cells and tissues as an off-the-shelf product. In this scenario, rejection problems induced by adaptive immune responses have to be handled. Therefore, it is of great interest to evaluate the immunogenicity as well the immunomodulatory capacity of either primary cells or stem cells and their progenitors that might be applied in regenerative approaches using appropriate in vitro and in vivo screening systems.

For several applications, cells have to be combined with extracellular matrix structures or synthetic matrix components. Matrices and their potential degradation products are able to trigger inflammation and immune responses and must therefore be examined in this regard.

Research Focus

The focus of the research is the analysis of the immunogenic and inflammatory characteristics and immunomodulatory capacities of stem cells and their derivatives along with other primary cell types for potential therapeutic applications.

First, we are studying the immunogenicity of different primary cell types (e.g. endothelial cells, endothelial progenitor cells, mesenchymal stromal cells, cardiac derived progenitor cells, nucleus pulposus cells). To elucidate the immune responses of the innate as well as the adaptive system, we have developed a set of in vitro assays to evaluate proliferation, apoptosis induction, cytotoxicity, complement activation and cytokine/chemokine release.

Secondly, the modulation and tissue repair capacity mediated by stem cells and their derivatives was analyzed in more detail. We designed a set of in vitro test systems to characterize those effects for Mesenchymal stromal cells (MSC), mainly of rat and human origin. A flow cytometry panel for the phenotypic characterization of human MSC from different sources was developed. Additionally, we analyzed the modulatory capacity of rat MSC on immune cell proliferation in a 3D culture system. The efficacy of MSCs or their secreted mediators or membrane vesicles to protect tissue from ischemic damage can be evaluated in a pre-clinical model of rat kidney transplantation with prolonged ischemia.

Third, in addition to the analysis of cellular immunogenicity, we are focusing on the immune responses mediated by biological matrices and their components of the extracellular matrix, especially of xenogeneic and human origin. Moreover, synthetic hybrid-matrices consisting of polymers and ECM proteins are tested for the induction of inflammation and innate or adaptive immune responses. Based on this research, new strategies to overcome immune responses against matrix structures in heart valve transplantations are developed.


Prof. Dr. Martina Seifert
Phone: +49 (0)30 450 539 435
Fax: +49 (0)30 450 524 962
E-Mail: martina.seifertcharitede

Christien Beez
Phone: +49 (0)30 450 539 463

Falk Diedrichs
PhD (Medicine)
Tel.: +49 (0)30 450 539 463
E-Mail: falk.diedrichscharitede

Dipl.-Biol. Naima Souidi
Phone: +49 (0)30 450 539 508
E-Mail: naima.souidicharitede

Maria Schneider
Phone: +49 (0) 30 450 539 508
E-Mail: maria.schneidercharitede

Niklas Fellmer
Tel.: +49 (0) 30 450 539 463
E-Mail: niklas.fellmercharitede

Victoria Reinhold
Tel.: +49 (0) 30 450 539 463
E-Mail: victoria.reinholdtcharitede

Thu Thao Nguyen
Tel.: +49 (0) 30 450 539 463
E-Mail: thu-thao.nguyencharitede


Meaghan Stolk


  • Primary cell and stem cell cultures
  • FACS analysis
  • Magnetic cell sorting
  • Proliferation assays (CFSE-based)
  • Cytotoxicity assays (Calcein-based)
  • Antibody / Complement Assays
  • Cytokine detection assays (CBA-Technology)
  • Quantitative real time RT-PCR
  • Immunohistology
  • Cell labeling techniques
  • Rat model: Kidney transplantation


  • DFG project (657/4-3): Modifikation decellularisierter, autolog wiederbesiedelter, xenogener Pulmonalklappen zur Verwendung als Aortenklappen, 03/2007-03/2010
  • BSRT project: Analysis of immunogenicity and immunomodulatory features of human endothelial progenitor cells (EPC) derived endothelial cells, start 09/2010, collaboration with platform F1 (Dr. C. Schmidt-Lucke)


  • Ladhoff J, Bader M, Brösel S, Effenberger E, Westermann D, Volk HD, Seifert M. Low immunogenicity of endothelial derivatives from rat embryonic stem cell-like cells. Cell Research. 2009;19: 507-518.
  • Ladhoff J, Fleischer B, Hara Y, Volk HD, Seifert M. Immune privilege of endothelial cells differentiated from endothelial progenitor cells. J Cardiovasc Res. 2010; 88:121-129.
  • Bayrak A, Tyralla M, Ladhoff J, Schleicher M, Stock UA, Volk HD, Seifert M. Human immune responses to porcine xenogeneic matrices and their extracellular matrix constituents in vitro. Biomaterials. 2010; 31(14):3793-803.
  • Hoogduijn MJ, Popp FC, Grohnert A, Crop MJ, van Rhijn M, Rowshani AT, Eggenhofer E, Renner P, Reinders ME, Rabelink TJ, van der Laan LJ, Dor FJ, Ijzermans JN, Genever PG, Lange C, Durrbach A, Houtgraaf JH, Christ B, Seifert M, Shagidulin M, Donckier V, Deans R, Ringden O, Perico N, Remuzzi G, Bartholomew A, Schlitt HJ, Weimar W, Baan CC, Dahlke MH; MISOT Study Group. Advancement of mesenchymal stem cell therapy in solid organ transplantation (MISOT).Transplantation. 2010;90(2):124-6.
  • Deuse T, Seifert M, Phillips N, Fire A, Tyan D, Kay M, Tsao M, Velden J, Eiermann T, Volk HD, Reichenspurner H, Robbins RC, Schrepfer S. HLA I knockdown human embryonic stem cells induce host ignorance and achieve prolonged xenogeneic survival. Circulation 2011; 124 (11): S3-9.
  • Flemming A, Schallmoser K, Strunk D, Stolk M, Volk HD, Seifert M. Immunomodulative efficacy of bone marrow-derived mesenchymal stem cells cultured in human platelet lysate. J Clin Immunol. 2011;31(6):1143-56.
  • Hara Y, Stolk M, Ringe J, Dehne T, Ladhoff J, Kotsch K, Reutzel-Selke A, Reinke P, Volk HD, Seifert M. In vivo effect of bone marrow-derived mesenchymal stem cells in a rat kidney transplantation model with prolonged cold ischemia. Transpl Int. 2011;24(11):1112-23.
  • Haag M, Stolk M, Ringe J, Linthout SV, Tschöpe C, Sittinger M, Seifert M. Immune attributes of cardiac-derived adherent proliferating (CAP) cells in cardiac therapy. J Tissue Eng Regen Med. 2012 Mar 2. doi: 10.1002/term.531. [Epub ahead of print]
  • Seifert M, Lubitz A, Trommer J, Könnig D, Korus G, Marx U, Volk HD, Duda G, Kasper G, Lehmann K, Stolk M, Giese C. Crosstalk between immune cells and mesenchymal stromal cells in a 3D bioreactor system. Int J Artif Organs,doi 10.5301/IJAO.5000118.
  • Seifert M, Stolk M, Polenz D, Volk HD. Detrimental effects of rat mesenchymal stromal cell pre-treatment in a model of acute kidney rejection. Front Immunol 2012; 3:202.
  • Souidi N, Stolk M, Seifert M. Ischemia-reperfusion injury: beneficial effects of mesenchymal stromal cells. Curr Opin Organ Transplant. 2013 Feb;18 (1) :34-43. PMID: 23254704
  • Bayrak A, Prüger P, Stock UA, Seifert M. Absence of immune responses with xenogeneic collagen and elastin. Tissue Eng Part A. 2013; 21: 3289-3297.
  • Seifert M, Bayrak A, Stolk M, Souidi N, Schneider M, Stock UA, Brockbank KG. Xeno-immunogenicity of ice-free cryopreserved porcine leaflets. J Surg Res. 2015; 193(2): 933-941.
  • Stich S, Stolk M, Girod PP, Thome C, Sittinger M, Ringe J, Seifert M, Hegewald AA. Regenerative and immunogenic characteristics of cultured nucleus pulposus cells from human cervical intervertebral discs. PLoS One. 2015; 10(5): e0126954.
  • Stolk M, Seifert M. Protein contaminations impact quantification and functional analysis of extracellular vesicle preparations from mesenchymal stromal cells. JSRM. 2015; 11(2), P44-47; ePub Code: 011020400002EPA270715.
  • Schneider M, Souidi N, Stock U, Brockbank KG, Stamm C, Seifert M. Human Macrophage Activation and Polarization in Response to Cryopreserved Cardiovascular Matrices. Tissue Engineering. 2015; Part A 21: S236-S237.