TY  - JOUR
A1  - Eckert, Ina N.
A1  - Ribechini, Eliana
A1  - Jarick, Katja J.
A1  - Strozniak, Sandra
A1  - Potter, Sarah J.
A1  - Beilhack, Andreas
A1  - Lutz, Manfred B.
T1  - VLA-1 Binding to Collagen IV Controls Effector T Cell Suppression by Myeloid-Derived Suppressor Cells in the Splenic Red Pulp
JF  - Frontiers in Immunology
N2  - Myeloid-derived suppressor cells (MDSCs) represent a major population controlling T cell immune responses. However, little is known about their molecular requirements for homing and T cell interaction to mediate suppression. Here, we investigated the functional role of the homing and collagen IV receptor VLA-1 (α1β1-integrin) on in vitro GM-CSF generated murine MDSCs from wild-type (WT) and CD49a/α1-integrin (Itga1\(^{−/−}\)) gene-deficient mice. Here, we found that effector (Teff) but not naive (Tn) CD4\(^+\) T cells express VLA-1 and monocytes further up-regulated their expression after culture in GM-CSF when they differentiated into the monocytic subset of resting MDSCs (R-MDSCs). Subsequent activation of R-MDSCs by LPS+IFN-γ (A-MDSCs) showed increased in vitro suppressor potential, which was independent of VLA-1. Surprisingly, VLA-1 deficiency did not influence A-MDSC motility or migration on collagen IV in vitro. However, interaction times of Itga1\(^{−/−}\) A-MDSCs with Teff were shorter than with WT A-MDSCs on collagen IV but not on fibronectin substrate in vitro. After injection, A-MDSCs homed to the splenic red pulp where they co-localized with Teff and showed immediate suppression already after 6 h as shown by inhibition of T cell proliferation and induction of apoptosis. Injection of A-MDSCs from Itga1\(^{−/−}\) mice showed equivalent homing into the spleen but a reduced suppressive effect. Interaction studies of A-MDSCs with Teff in the subcapsular red pulp with intravital two-photon microscopy revealed also here that MDSC motility and migration parameters were not altered by VLA-1 deficiency, but the interaction times with Teff were reduced. Together, our data point to a new role of VLA-1 adhesion to collagen IV as a prerequisite for extended contact times with Teff required for suppression.
KW  - myeloid-derived suppressor cells (MDSCs)
KW  - T cells
KW  - VLA-1
KW  - homing
KW  - spleen
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-222671
SN  - 1664-3224
VL  - 11
ER  - 
TY  - JOUR
A1  - Ribechini, Eliana
A1  - Eckert, Ina
A1  - Beilhack, Andreas
A1  - Du Plessis, Nelita
A1  - Walzl, Gerhard
A1  - Schleicher, Ulrike
A1  - Ritter, Uwe
A1  - Lutz, Manfred B.
T1  - Heat-killed Mycobacterium tuberculosis prime-boost vaccination induces myeloid-derived suppressor cells with spleen dendritic cell–killing capability
JF  - JCI Insight
N2  - Tuberculosis patients and mice infected with live Mycobacterium tuberculosis accumulate high numbers of myeloid-derived suppressor cells (MDSCs). Here, we hypothesized that dead M. tuberculosis vaccines also may induce MDSCs that could impair the efficacy of vaccination. We found that repeated injections of M. tuberculosis vaccines (heat-killed M. tuberculosis in incomplete Freund’s adjuvant, such as Montanide) but not single or control vaccines without M. tuberculosis strongly expanded CD11b\(^+\) myeloid cells in the spleen, leading to T cell suppression of proliferation and killing ex vivo. Dead M. tuberculosis vaccination induced the generation of CD11b\(^+\)Ly6C\(^{hi}\)CD115\(^+\) iNOS/Nos2\(^+\) monocytic MDSCs (M-MDSCs) upon application of inflammatory or microbial activation signals. In vivo these M-MDSCs were positioned strategically in the splenic bridging channels and then positioned in the white pulp areas. Notably, within 6–24 hours, in a Nos2-dependent fashion, they produced NO to rapidly kill conventional and plasmacytoid DCs while, surprisingly, sparing T cells in vivo. Thus, we demonstrate that M. tuberculosis vaccine induced M-MDSCs do not directly suppress effector T cells in vivo but, instead, indirectly by killing DCs. Collectively, we demonstrate that M. tuberculosis booster vaccines induce M-MDSCs in the spleen that can be activated to kill DCs. Our data suggest that formation of MDSCs by M. tuberculosis vaccines should be investigated also in clinical trials.
KW  - Immunology
KW  - Infectious disease
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-201973
VL  - 13
IS  - 4
ER  - 
TY  - JOUR
A1  - Chopra, Martin
A1  - Biehl, Marlene
A1  - Steinfatt, Tim
A1  - Brandl, Andreas
A1  - Kums, Juliane
A1  - Amich, Jorge
A1  - Vaeth, Martin
A1  - Kuen, Janina
A1  - Holtappels, Rafaela
A1  - Podlech, Jürgen
A1  - Mottok, Anja
A1  - Kraus, Sabrina
A1  - Jordán-Garotte, Ana-Laura
A1  - Bäuerlein, Carina A.
A1  - Brede, Christian
A1  - Ribechini, Eliana
A1  - Fick, Andrea
A1  - Seher, Axel
A1  - Polz, Johannes
A1  - Ottmueller, Katja J.
A1  - Baker, Jeannette
A1  - Nishikii, Hidekazu
A1  - Ritz, Miriam
A1  - Mattenheimer, Katharina
A1  - Schwinn, Stefanie
A1  - Winter, Thorsten
A1  - Schäfer, Viktoria
A1  - Krappmann, Sven
A1  - Einsele, Hermann
A1  - Müller, Thomas D.
A1  - Reddehase, Matthias J.
A1  - Lutz, Manfred B.
A1  - Männel, Daniela N.
A1  - Berberich-Siebelt, Friederike
A1  - Wajant, Harald
A1  - Beilhack, Andreas
T1  - Exogenous TNFR2 activation protects from acute GvHD via host T reg cell expansion
JF  - Journal of Experimental Medicine
N2  - Donor CD4\(^+\)Foxp3\(^+\) regulatory T cells (T reg cells) suppress graft-versus-host disease (GvHD) after allogeneic hematopoietic stem cell transplantation (HCT allo-HCT]). Current clinical study protocols rely on the ex vivo expansion of donor T reg cells and their infusion in high numbers. In this study, we present a novel strategy for inhibiting GvHD that is based on the in vivo expansion of recipient T reg cells before allo-HCT, exploiting the crucial role of tumor necrosis factor receptor 2 (TNFR2) in T reg cell biology. Expanding radiation-resistant host T reg cells in recipient mice using a mouse TNFR2-selective agonist before allo-HCT significantly prolonged survival and reduced GvHD severity in a TNFR2-and T reg cell-dependent manner. The beneficial effects of transplanted T cells against leukemia cells and infectious pathogens remained unaffected. A corresponding human TNFR2-specific agonist expanded human T reg cells in vitro. These observations indicate the potential of our strategy to protect allo-HCT patients from acute GvHD by expanding T reg cells via selective TNFR2 activation in vivo.
KW  - Tumor-necrosis-factor
KW  - Regulatory-cells
KW  - Bone marrow transplantantation
KW  - Graft-versus-leukemia
KW  - Rheumatoid arthritis
KW  - Autoimmune diseases
KW  - Factor receptor
KW  - Alpha therapy
KW  - Expression
KW  - Suppression
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-187640
VL  - 213
IS  - 9
ER  -