Gregor Bein

Justus-Liebig-Universität Gießen, Giessen, Hesse, Germany

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Publications (159)513.44 Total impact

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    ABSTRACT: Background: Alloantibodies against human platelet antigens (HPAs) are of clinical significance in immune-mediated thrombocytopenia such as fetal/neonatal alloimmune thrombocytopenia (FNAIT), posttransfusion purpura, and platelet (PLT) transfusion refractoriness. The gold standard for the detection of these antibodies is the monoclonal antibody immobilization of PLT antigens (MAIPA) assay. Both requirement of typed donor PLT panels and technical expertise often restrict its use to reference laboratories. Study design and methods: An easy-to-use, bead-based assay (BBA) has been introduced recently. In this study, we compared MAIPA and BBA test results for 126 serum samples from women who gave birth to a child with FNAIT including rare HPA specificities (n = 111) and from patients with PLT transfusion refractoriness (n = 15). Results: For sera with defined allospecificities, the number of BBA false-negatives was 12 of 126, or 9.5%, and the number of BBA false-positives (i.e., detection of additional specificities) was two of 126, or 1.6%. BBA had major problems in detecting antibodies against HPA-3a (3/15 undetected = 20% failure rate) and HPA-3b (5/6 undetected = 83.3% failure rate), but performed well in detecting typical FNAIT- or PLT transfusion refractoriness-associated antibodies including HPA-1a (35/35 = 100%), HPA-1b (15/15 = 100%), HPA-5b (22/24 = 91.6%), and glycoprotein IV (6/6 = 100%). Conclusion: BBA might be a useful and time-saving tool in the initial laboratory work-up of suspected PLT alloimmunization when an appropriate algorithm ensures follow-up investigation of BBA-negative sera.
    Transfusion 11/2015; DOI:10.1111/trf.13351 · 3.23 Impact Factor
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    ABSTRACT: Background Numerous studies have described the immunosuppressive capacity of mesenchymal stem cells (MSC) but these studies use mixtures of heterogeneous progenitor cells for in vitro expansion. Recently, multipotent MSC have been prospectively identified in murine bone marrow (BM) on the basis of PDFGRa+ SCA1+ CD45− TER119− (PαS) expression but the immunomodulatory capacity of these MSC is unknown. Methods We isolated PαS MSC by high-purity FACS sorting of murine BM and after in vitro expansion we analyzed the in vivo immunomodulatory activity during acute pneumonia. PαS MSC (1 × 106) were applied intratracheally 4 h after acute respiratory Klebsiella pneumoniae induced infection. Results PαS MSC treatment resulted in significantly reduced alveolitis and protein leakage in comparison to mock-treated controls. PαS MSC-treated mice exhibited significantly reduced alveolar TNF-α and IL-12p70 expression, while IL-10 expression was unaffected. Dissection of respiratory dendritic cell (DC) subsets by multiparameter flow cytometry revealed significantly reduced lung DC infiltration and significantly reduced CD86 costimulatory expression on lung CD103+ DC in PαS MSC-treated mice. In the post-acute phase of pneumonia, PαS MSC-treated animals exhibited significantly reduced respiratory IL-17+ CD4+ T cells and IFN-γ+ CD4+ T cells. Moreover, PαS MSC treatment significantly improved overall pneumonia survival and did not increase bacterial load. Conclusion In this study we demonstrated for the first time the feasibility and in vivo immunomodulatory capacity of prospectively defined MSC in pneumonia. Electronic supplementary material The online version of this article (doi:10.1186/s12931-015-0288-1) contains supplementary material, which is available to authorized users.
    Respiratory Research 10/2015; 16(1). DOI:10.1186/s12931-015-0288-1 · 3.09 Impact Factor
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    ABSTRACT: BACKGROUND Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is caused by the destruction of platelets (PLTs) in the fetus or newborn by maternal PLT antibodies that crossed the placenta during pregnancy.STUDY DESIGN AND METHODS In this study, we aim to elucidate the properties of a new PLT alloantigen (Lapa) that is associated with a severe case of FNAIT. Analysis of maternal serum with phenotyped PLTs by monoclonal antibody–specific immobilization of platelet antigens showed positive reaction against PLT glycoprotein (GP)IIb/IIIa and HLA Class I expressed on paternal PLTs.RESULTSIn contrast to GPIIIa-reactive anti-HPA-1a, anti-Lapa alloantibodies precipitated predominantly GPIIb. Indeed, a point mutation G>C at Position 2511 located in Exon 25 of the ITGA2B gene was found in Lapa-positive donors. This mutation causes an amino exchange Gln>His at Position 806 located in the calf-2 domain of GPIIb. Lapa-positive individuals were not found in 300 random blood donors. Our expression study showed that anti-Lapa alloantibodies reacted with stable transfected HEK293 cells expressing the mutated GPIIb isoform (His806). CHO cells carrying this isoform, however, failed to react with anti-Lapa alloantibodies, indicating that Lapa epitopes depend on the Gln806His mutation and the carbohydrate composition of the GPIIb. This mutation did not hamper the binding of anti-HPA-3a, which recognizes a point mutation (Ile843Ser) located in calf-2 domain. Finally, we found that Lapa and some HPA-3a epitopes are sensitive to O-glycanase.CONCLUSIONS This study not only underlines the relevance of rare HPAs on the pathomechanism of FNAIT, but also helps to understand the pitfalls of serologic assays to detect anti-GPIIb alloantibodies.
    Transfusion 08/2015; DOI:10.1111/trf.13238 · 3.23 Impact Factor
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    ABSTRACT: Fetal human platelet antigen (HPA) genotyping is required to determine whether the fetus is at risk and whether prenatal interventions to prevent fetal bleeding are required in pregnant women with a history of fetal and neonatal alloimmune thrombocytopenia (FNAIT). Methods for noninvasive genotyping of HPA alleles with the use of maternal plasma cell-free DNA were published recently but do lack internal controls to exclude false-negative results. Cell-free DNA was isolated from plasma of four pregnant women with a history of FNAIT caused by anti-HPA-1a and controls. A primer panel was designed to target sequences flanking single-nucleotide polymorphisms (SNPs)/exonic regions of ITGB3 (HPA-1), ITGA2B (HPA-3), ITGA2 (HPA-5), CD109 (HPA-15), RHD, RHCE, KEL, DARC, SLC14A1, GYPA, GYPB, and SRY. These regions and eight anonymous SNPs were massively parallel sequenced by semiconductor technology. The mean (±SD) number of reads for targeted SNPs was 5255 (±2838). Fetal DNA was detected at a median of 4.5 (range, 2-8) polymorphic loci. The mean fractional fetal DNA concentration in cell-free maternal plasma was 8.36% (range, 4.79%-15.9%). For HPA-1, nonmaternal ITGB3 sequences (c.176T, HPA-1a) were detected in all HPA-1ab fetuses. One HPA-1bb fetus was unequivocally identified, showing the pregnancy was not at risk of FNAIT. We have successfully established massively parallel sequencing as a novel reliable method for noninvasive genotyping of fetal HPA-1a alleles. This technique may also allow the safe detection of other fetal blood group polymorphisms frequently involved in FNAIT and hemolytic disease of the newborn. © 2015 AABB.
    Transfusion 04/2015; 55(6pt2). DOI:10.1111/trf.13102 · 3.23 Impact Factor
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    ABSTRACT: Extracorporeal photopheresis (ECP) is a widely used clinical cell-based therapy exhibiting efficacy in heterogenous immune-mediated diseases such as cutaneous T cell lymphoma, graft-versus-host disease, and organ allograft rejection. Despite its documented efficacy in cancer immunotherapy, little is known regarding the induction of immunostimulatory mediators by ECP. In this article, we show that ECP promotes marked release of the prototypic immunostimulatory cytokine IL-1β. ECP primes IL-1β production and activates IL-1β maturation and release in the context of caspase-1 activation in monocytes and myeloid dendritic cells. Of interest, IL-1β maturation by ECP was fully intact in murine cells deficient in caspase-1, suggesting the predominance of an inflammasome-independent pathway for ECP-dependent IL-1β maturation. Clinically, patient analysis revealed significantly increased IL-1β production in stimulated leukapheresis concentrates and peripheral blood samples after ECP. Collectively, these results provide evidence for promotion of IL-1β production by ECP and offer new insight into the immunostimulatory capacity of ECP. Copyright © 2015 by The American Association of Immunologists, Inc.
    The Journal of Immunology 02/2015; 194(6). DOI:10.4049/jimmunol.1400694 · 4.92 Impact Factor
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    ABSTRACT: BACKGROUND Peripheral blood progenitor cells (PBPCs) are the most common stem cell source for allogeneic transplantations. Analysis of our collection data obtained with a Spectra Optia device (Terumo) for apheresis demonstrated collection efficacies (CEs) exceeding our internal target levels of 5 × 106 CD34+ cells/kg body weight of the recipient when collected on Day 5. We thus aimed to investigate whether collection on Day 4 would lead to adequate amounts of PBPCs while minimizing granulocyte–colony-stimulating factor (G-CSF) exposure in healthy donors.STUDY DESIGN AND METHODS We compared feasibility and effectiveness of Day 5 versus Day 4 collections with data obtained from 23 and 18 allogeneic procedures, respectively.RESULTSBoth groups were comparable with regard to donor and collection characteristics. Product characteristics as well as platelet loss, CE, throughput, and collection rate did not differ between both protocols. A higher contamination with white blood cells (WBCs; ×109/L) was observed in products collected on Day 5 compared to Day 4 (231 [range, 181-299] vs. 203 [range, 165-239]; p = 0.004). A second apheresis procedure was required in three of 23 patients and three of 18 patients, respectively (p = 0.6) to obtain the required PBPC dose.CONCLUSIONSPBPC apheresis on Day 4 seems as feasible and effective as collection on Day 5. Collection on Day 4 produces lower WBC content in the product and allows a reduction in G-CSF exposure to healthy donors.
    Transfusion 02/2015; 55(6). DOI:10.1111/trf.13002 · 3.23 Impact Factor
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    ABSTRACT: Mesenchymal stem cells (MSC) Mesenchymal stroma cells (MSC) are increasingly recognized for various applications of cell-based therapies such as regenerative medicine or immunomodulatory treatment strategies. Standardized large-scale expansions of MSC under good manufacturing practice (GMP)-compliant conditions avoiding animal derived components are mandatory for further evaluation of these novel therapeutic approaches in clinical trials. We applied a novel automated hollow-fiber cell expansion system (CED) for in vitro expansion of human bone marrow derived MSC employing a GMP-compliant culture medium with human platelet lysate (HPL). Between 8 and 32 ml primary bone marrow aspirate were loaded into the hollow fiber CED and cultured for 15-27 days. 2-58 million MSC were harvested after primary culture. Further GMP-compliant cultivation of second passage MSC for 13 days led to further 10-20 fold enrichment. Viability, surface antigen expression, differentiation capacity and immunosuppressive function of MSC cultured in the hollow fiber CED were in line with standard criteria for MSC definition. We conclude that MSC can be enriched from primary bone marrow aspirate in a GMP-conform manner within a closed hollow fiber bioreactor and maintain their T lymphocyte inhibitory capacity. Standardized and reliable conditions for large scale MSC expansion pave the way for safe applications in humans in different therapeutic approaches.
    Jahrestagung der Deutschen Gesellschaft für Transfusionsmedizin und Immunhämatologie e. V. (DGTI), Dresden; 09/2014
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    ABSTRACT: Extracorporeal photopheresis (ECP) is an important cell-based therapy for graft-versus-host disease (GVHD); however, the blood volume required per treatment to achieve a clinical response is unknown. We developed a mini-ECP technique (mini-ECP) using only 100 to 200 mL of whole blood for patients with contraindications for apheresis or low body weight. Sixteen patients (n = 13 acute, n = 3 chronic GVHD) with a median body weight of 19 kg (range, 7-48 kg) received 460 mini-ECP treatments with a median duration of 115 days (range, 49-973 days). Mini-ECP was well tolerated, and acute GVHD resolved completely in nine of 13 patients and partially in two patients but not in two patients. Cutaneous chronic GVHD exhibited a mixed response (one complete, one partial, and one no response). These results indicate mini-ECP as a novel and less invasive therapy for patients with GVHD and contraindications for apheresis.
    Transfusion 03/2014; 54(8). DOI:10.1111/trf.12596 · 3.23 Impact Factor
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    Ulrich J Sachs · Gregor Bein ·

    Querschnitts-Leitlinien (BÄK) zur Therapie mit Blutkomponenten und Plasmaderivaten, 4., überarbeitet und aktualisiert edited by Vorstand der Bundeärztekammer, 01/2014: chapter 11; , ISBN: 978-3-7691-1269-6
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    ABSTRACT: Immune thrombocytopenia (ITP) is a bleeding disorder caused by IgG autoantibodies (AAbs) directed against platelets (PLTs). IgG effector functions depend on their Fc-constant region which undergoes posttranslational glycosylation. We investigated the role of Asn279-linked N-glycan of AAbs in vitro and in vivo. AAbs were purified from ITP patients (n=15) and N-glycans were enzymatically cleaved by endoglycosidase F. The effects of native AAbs and deglycosylated AAbs were compared in vitro on enhancement of phagocytosis of platelets by monocytes and complement fixation and activation applying flow cytometry, laser scanning microscopy, and a complement consumption assay. AAb-induced platelet phagocytosis was inhibited by N-glycan cleavage (median phagocytic activity: 8% vs 0.8%, p=0.004). Seven out of 15 native AAbs bound C1q and activated complement. N-glycan cleavage significantly reduced both effects. In vivo survival of human PLTs was assessed after co-transfusion with native or N-glycan cleaved AAbs in a NOD/SCID mouse model. Injection of AAbs resulted in rapid clearance of human platelets compared to control (platelet clearance after 5h (CL5h)75% vs 30%, p<0.001). AAbs that were able to activate complement induced more pronounced platelet clearance in the presence of complement compared to the clearance in the absence of complement (CL5h 82% vs 62%, p=0.003). AAbs lost their ability to destroy platelets in vivo after deglycosylation (CL5h 42%, p<0.001). N-glycosylation of human ITP AAbs appears to be required for platelet phagocytosis and complement activation, reducing platelet survival in vivo. Posttranslational modification of AAbs may constitute an important determinant for the clinical manifestation of ITP.
    Thrombosis and Haemostasis 09/2013; 110(6). DOI:10.1160/TH13-04-0294 · 4.98 Impact Factor
  • Willy A Flegel · Ion Chiosea · Ulrich J Sachs · Gregor Bein ·
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    ABSTRACT: Genotyping for red blood cell (RBC), platelet (PLT), and granulocyte antigens is a new tool for clinical pathology, transfusion medicine services, and blood banks. Proficiency in laboratory tests can be established by external quality assessments (EQAs), which are required for clinical application in many health care systems. There are few EQAs for molecular immunohematology. We analyzed the participation and pass rates in an EQA for RBC, PLT, and granulocyte antigens. This EQA was distributed by INSTAND, a large nonprofit provider of proficiency tests, twice per year since Fall 2006 as EQA Number 235 Immunohematology A (molecular diagnostic). The coordinators defined at the outset which alleles are mandatory for detection. The number of participants steadily increased from 51 to 73 per proficiency by Fall 2012. More than 60 institutions utilized this EQA at least once a year. Approximately 80% of them participated in RBC, 68% in PLT, and 22% in granulocyte systems. With the exceptions of RHD (82%) and granulocytes (85%), pass rates exceeded 93%. While the pass rate increased for granulocyte and decreased for the ABO system, the pass rates for the other systems changed little over 6½ years. The INSTAND proficiency test program was regularly used for EQA by many institutions, particularly in Central Europe. While the technical standards and pass rates in the participating laboratories were high, there has been little improvement in pass rates since 2006.
    Transfusion 09/2013; 53(11). DOI:10.1111/trf.12414 · 3.23 Impact Factor
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    ABSTRACT: Klebsiella pneumoniae is a leading cause of severe hospital-acquired respiratory tract infections and death but little is known regarding the modulation of respiratory dendritic cell (DC) subsets. Plasmacytoid DC (pDC) are specialized type 1 interferon producing cells and considered to be classical mediators of antiviral immunity. By using multiparameter flow cytometry analysis we have analysed the modulation of respiratory DC subsets after intratracheal Klebsiella pneumonia infection. Data indicate that pDCs and MoDC were markedly elevated in the post acute pneumonia phase when compared to mock-infected controls. Analysis of draining mediastinal lymph nodes revealed a rapid increase of activated CD103+ DC, CD11b+ DC and MoDC within 48 h post infection. Lung pDC identification during bacterial pneumonia was confirmed by extended phenotyping for 120G8, mPDCA-1 and Siglec-H expression and by demonstration of high Interferon-alpha producing capacity after cell sorting. Cytokine expression analysis of ex vivo-sorted respiratory DC subpopulations from infected animals revealed elevated Interferon-alpha in pDC, elevated IFN-gamma, IL-4 and IL-13 in CD103+ DC and IL-19 and IL-12p35 in CD11b+ DC subsets in comparison to CD11c+ MHC-class IIlow cells indicating distinct functional roles. Antigen-specific naive CD4+ T cell stimulatory capacity of purified respiratory DC subsets was analysed in a model system with purified ovalbumin T cell receptor transgenic naive CD4+ responder T cells and respiratory DC subsets, pulsed with ovalbumin and matured with Klebsiella pneumoniae lysate. CD103+ DC and CD11b+ DC subsets represented the most potent naive CD4+ T helper cell activators. These results provide novel insight into the activation of respiratory DC subsets during Klebsiella pneumonia infection. The detection of increased respiratory pDC numbers in bacterial pneumonia may indicate possible novel pDC functions with respect to lung repair and regeneration.
    Respiratory research 09/2013; 14(1):91. DOI:10.1186/1465-9921-14-91 · 3.09 Impact Factor
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    ABSTRACT: Three different apheresis systems were used in our center for the collection of peripheral blood progenitor cells (PBPCs): COM.TEC (Fresenius Healthcare), COBE Spectra, and Spectra Optia (both from Caridian BCT). We compared 131 autologous and 56 allogeneic apheresis procedures to elucidate feasibility and effectiveness of the different systems. Collection efficiacy varied significantly with lowest results obtained with COBE Spectra. COM.TEC and Spectra Optia produced lower WBC contamination than COBE Spectra, but at the expense of higher product volume and longer apheresis time. High collection efficacy and a low product volume may be favorable characteristics of the Spectra Optia.
    Transfusion and Apheresis Science 07/2013; 49(3). DOI:10.1016/j.transci.2013.06.002 · 0.77 Impact Factor
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    ABSTRACT: Fetal/neonatal alloimmune thrombocytopenia (FNAIT) is often caused by maternal alloantibodies against the human platelet antigen (HPA)-1a, which opsonize fetal platelets. Subsequent platelet destruction is mediated via the Fc-part of the alloantibodies. The monoclonal antibody SZ21 binds to the HPA-1a-epitope and inhibits binding of maternal alloantibodies. However, it also promotes complement activation and phagocytosis. Deglycosylation of antibodies abrogates the Fc-related effector functions. We modified the N-glycan of SZ21 by Endoglycosidase F. The in vivo transplacental transport of N-glycan modified (NGM)-SZ21 was not impaired. When injected into pregnant mice, both native SZ21 and NGM-SZ21 were transported equally into fetal circulation (8.9% vs. 8.7%, respectively, p=0.58). Neither the binding properties of NGM-SZ21 to HPA-1a in surface plasmon resonance, nor inhibition of anti-HPA-1a-induced platelet phagocytosis were affected by N-glycan modification. NGM-SZ21 prevented platelet destruction induced by maternal anti-HPA-1a antibodies in vivo in a NOD/SCID mouse model (platelet clearance after 5h; 18% vs. 62%, in the presence or absence of NGM-SZ21, respectively, p=0.013). Deglycosylation of SZ21 abrogates Fc effector functions, without interfering with placental transport or the ability to block anti-HPA-1a binding. Humanized, deglycosylated anti-HPA-1a monoclonal antibodies may represent a novel treatment strategy to prevent anti-HPA-1a-mediated platelet destruction in FNAIT.
    Blood 05/2013; 122(3). DOI:10.1182/blood-2012-11-468561 · 10.45 Impact Factor
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    J Slonka · M Alrifai · G Bein · U J Sachs ·

    Transfusion Medicine 03/2013; 23(3). DOI:10.1111/tme.12024 · 1.65 Impact Factor
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    Transfusion 03/2013; 53(3):482. DOI:10.1111/j.1537-2995.2012.03844.x · 3.23 Impact Factor
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    ABSTRACT: Background: Maternal anti-HPA-1a alloantibodies are responsible for most cases of severe fetal and neonatal alloimmune thrombocytopenia (FNAIT). The presence of HPA-1a alloantibodies in maternal blood alone does not predict the fetal platelet (PLT) count, and the predictivity of antibody titers determined by enzyme immunoassays (EIAs) is debated. In contrast to EIA, surface plasmon resonance (SPR) provides information on antibody-binding properties. Study design and methods: Sequential sera from pregnant women with expected FNAIT were assessed for HPA-1a alloantibodies using SPR. Group I (n = 6) was treated with intravenous immunoglobulin (IVIG) and steroids beginning at 19 weeks of gestation (w.g.), and Group II (n = 4) received intrauterine PLT transfusions (IUT) beginning at 22 w.g. Maternal alloantibodies were quantified using an HPA-1a monoclonal antibody (MoAb) as a standard. Antibody avidity was determined as the ratio of B700 (end of the dissociation phase) to B350 (end of the association phase); the area under the curve (AUC) was calculated to determine overall antibody binding. Results: After 22 w.g., alloantibody characteristics remained stable in both groups, while there was a steep decrease in B700 and B350 values between 16 and 22 w.g. (assessed only in Group I), indicating a decrease in anti-HPA-1a alloantibody concentrations. Interestingly, the AUCs of the last maternal sample before elective delivery appeared to be correlated with fetal and neonatal PLT counts (p = 0.014 and 0.017, respectively). Conclusion: SPR provides quantitative information on HPA-1a alloantibody characteristics in addition to monoclonal antibody-specific immobilization of platelet antigens. SPR results can be calibrated using a MoAb standard and should be further assessed for a potential correlation with fetal PLT count.
    Transfusion 12/2012; 53(9). DOI:10.1111/trf.12051 · 3.23 Impact Factor
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    ABSTRACT: Mesenchymal stroma cells (MSC) are increasingly recognized for various applications of cell-based therapies such as regenerative medicine or immunomodulatory treatment strategies. Standardized large-scale expansions of MSC under good manufacturing practice (GMP) -compliant conditions avoiding animal derived components are mandatory for further evaluation of these novel therapeutic approaches in clinical trials. We applied a novel automated hollow-fiber cell expansion system (CES) for in vitro expansion of human bone marrow derived MSC employing a GMP-compliant culture medium with human platelet lysate (HPL). Between 8 and 32 ml primary bone marrow aspirate were loaded into the hollow fiber CES and cultured for 15-27 days. 2-58 million MSC were harvested after primary culture. Further GMP-compliant cultivation of second passage MSC for 13 days led to further 10-20 fold enrichment. Viability, surface antigen expression, differentiation capacity and immunosuppressive function of MSC cultured in the hollow fiber CES were in line with standard criteria for MSC definition. We conclude that MSC can be enriched from primary bone marrow aspirate in a GMP-conform manner within a closed hollow fiber bioreactor and maintain their T lymphocyte inhibitory capacity. Standardized and reliable conditions for large scale MSC expansion pave the way for safe applications in humans in different therapeutic approaches.
    Biochemical and Biophysical Research Communications 11/2012; 430(1). DOI:10.1016/j.bbrc.2012.11.001 · 2.30 Impact Factor
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    ABSTRACT: Human Vγ9δ2 (Vδ2) T cells represent a unique effector T cell population in humans and primates detecting nonpeptid phosphoantigens, playing an important role in antimicrobial and antitumor immunity. Currently, it is believed that various leukocyte subsets can promote phosphoantigen-driven Vδ2 cell expansion, but the essential cell type required remains elusive. We have used high purity cell sorting to analyze the cellular requirements for (E)-4-hydroxy-3-methyl-but-2-enyl-pyrophosphate (HMBPP)-driven Vδ2 cell expansion. To our knowledge, we show for the first time that primary human MHC-class II(+) cells are indispensable for HMBPP- and isopentenylpyrophosphate-driven Vδ2 cell expansion. In contrast, MHC-class II(-) cells are unable to promote Vδ2 cell expansion. Moreover, purified primary human TCRαβ(+) T cells, CD4(+), or CD8(+) T cells also failed to promote HMBPP-mediated Vδ2 expansion. Depletion of CD4(+)CD25(+) T cells demonstrated that inability of TCRαβ(+) cells to expand Vδ2 cells was not related to the presence of regulatory T cells. Separation of MHC-class II(+) cells into dendritic cells, monocytes, and B cells revealed that dendritic cells were the most potent Vδ2 expanders. Pulsing experiments demonstrated that HMBPP transforms MHC-class II(+) but not negative cells into Vδ2 expanders. MHC-class II-blocking experiments with mAbs and secondary MHC-class II induction on CD4(+) T cells after CD3/CD28 costimulation indicated that MHC-class II is necessary, but not sufficient to promote Vδ2 expansion. Our results provide novel insight into the primary cell-specific requirements for human Vδ2 expansion.
    The Journal of Immunology 10/2012; 189(11). DOI:10.4049/jimmunol.1200093 · 4.92 Impact Factor
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    ABSTRACT: Background Inbred mouse strains are used in different models of respiratory diseases but the variation of critical respiratory leukocyte subpopulations across different strains is unknown. Methods By using multiparameter flow cytometry we have quantitated respiratory leukocyte subsets including dendritic cells subpopulations, macrophages, classical T and B cells, natural killer cells, γδTCR+ T cells and lineage-negative leukocytes in the five most common inbred mouse strains BALB/c, C57BL/6, DBA/2, 129SV and C3H. To minimize confounding environmental factors, age-matched animals were received from the same provider and were housed under identical specific-pathogen-free conditions. Results Results revealed significant strain differences with respect to respiratory neutrophils (p=0.005; up to 1.4 fold differences versus C57BL/6 mice), eosinophils (p=0.029; up to 2.7 fold), certain dendritic cell subsets (p≤0.0003; up to 3.4 fold), T (p<0.001; up to 1.6 fold) and B lymphocyte subsets (p=0.005; up to 0.4 fold), γδ T lymphocytes (p=0.003; up to 1.6 fold), natural killer cells (p<0.0001; up to 0.6 fold) and lineage-negative innate leukocytes (p≤0.007; up to 3.6 fold). In contrast, total respiratory leukocytes, macrophages, total dendritic cells and bronchoalveolar lavage leukocytes did not differ significantly. Stimulation of respiratory leukocytes via Toll-like receptor 4 and 9 as well as CD3/CD28 revealed significant strain differences of TNF-α and IL-10 production. Conclusion Our study demonstrates significant strain heterogeneity of respiratory leukocyte subsets that may impact respiratory immunity in different disease models. Additionally, the results may help identification of optimal strains for purification of rare respiratory leukocyte subsets for ex vivo analyses.
    Respiratory research 10/2012; 13(1):94. DOI:10.1186/1465-9921-13-94 · 3.09 Impact Factor

Publication Stats

3k Citations
513.44 Total Impact Points


  • 1998-2015
    • Justus-Liebig-Universität Gießen
      • • Department of Internal Medicine
      • • Department of Pediatric Hematology and Oncology
      Giessen, Hesse, Germany
  • 2008
    • Universitätsklinikum Gießen und Marburg
      Marburg, Hesse, Germany
  • 1991-2008
    • Universität zu Lübeck
      • Institut für Transfusionsmedizin
      Lübeck Hansestadt, Schleswig-Holstein, Germany
  • 1993
    • Red Cross
      Washington, Washington, D.C., United States