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H J Kolb

Publications and source records attributed to H J Kolb.

At least 19 recordsLinked to original sources
PubMed2006

Graft-versus-host and graft-versus-leukemia reactions: a summary of the Seventh International Symposium held in Garmisch-Partenkirchen, Germany, February 22nd-25th, 2006, Tolerance and Immunity, an update on lymphoid malignancies.

The Seventh International Symposium on graft-versus-host and graft-versus-leukemia reactions was held in Garmisch Partenkirchen (Germany, near Lake Riessersee) between January 22nd and 25th, 2006. A total of more than 100 invited participants (scientists and clinicians working in the area of allogeneic stem cell transplantation) discussed research in the area of lymphoid malignancies. Major topics of the 2006 meeting were lymphocyte biology, experimental systems, lymphoma pathogenesis, cellular therapy in vivo and vitro, idiotype-specific responses and graft-versus-malignancy reactions for lymphomas and multiple myeloma. Further highlights were immune responses to blasts of ALL, haploidentical transplantation, role of natural killer cells, clinical guidelines for allogeneic transplantation and adoptive immunotherapy in chronic lymphocytic leukemia and multiple myeloma, new antibody-mediated strategies. As can be seen in the summaries of the individual presentations, progress was made in the understanding of lymphoma biology and in the clinical application of graft-versus-lymphoma or graft-versus-myeloma effects. Each day was followed by round-table discussions, which summarized new data and challenged established concepts. The discussions resulted in new insights and projects for basic research and clinical transplantation.

Animals↗
PubMed2006

Serum levels of sCD137 (4-1BB) ligand are prognostic factors for progression in acute myeloid leukemia but not in non-Hodgkin's lymphoma.

CD178 (Fas/APO-1 ligand) and CD137 ligand (CD137L) have previously been described in sera of patients with various malignancies and play an important role in the pathogenesis of various diseases. Recently, we demonstrated that low levels of soluble (s) CD137L and high levels of sCD178 correlate significantly with a long progression free survival in patients with myelodysplastic syndrome (MDS). In this study, we correlated sCD137L and sCD178 levels in sera of 42 samples of patients with acute myeloid leukemia (AML) and 46 samples of patients with non-Hodgkin's lymphoma (NHL) with stages, subtypes, and the clinical course of the diseases and determined cut-off values with maximum probability for significant differentiation between cases with higher/lower probability for progress free survival. In contrast to patients with MDS, surprisingly no correlation between sCD178 levels and different subtypes and stages or with prognosis in AML or NHL were observed. Regarding sCD137L, NHL-patients displayed lower levels compared with AML. Statistically significant higher median levels of sCD137L are present in patients with undifferentiated AML (M1/M2, 1,470 pg/mL), poor cytogenetic risk (288 pg/mL) and higher levels of BM-blasts (186 pg/mL) compared with patients with monocytoid AML (M4/M5, 89 pg/mL), intermediate cytogenetic risk (59 pg/mL) and lower levels of BM-blasts (14 pg/mL) respectively. Furthermore, in AML patients sCD137L levels correlate significantly with the probabilities to achieve complete remission (CR), stay in CR or with progress of the disease. Taken together, our data demonstrate that sCD137L can be used as a prognostic factor not only in MDS but also in AML.

4-1BB Ligand↗
PubMed2005

Lasting remission following multimodal treatment in a patient with metastatic breast cancer.

We report on a lasting remission from multimodal treatment in a patient with hepatic metastasized breast cancer. After surgical removal of a singular hepatic metastasis, the patient underwent leukapheresis of peripheral blood mononuclear cell (PBMCs). For induction chemotherapy, the patient received 2 cycles of epirubicin and paclitaxel (ET). After 1 cycle of epirubicin and ifosfamide (EI), peripheral blood stem cells were harvested. After a final cycle of ET, the patient underwent high-dose chemotherapy (HDCT; thiotepa 600 mg/m/melphalan 180 mg/m) and autologous stem cell transplantation. Once reconstitution was achieved, PBMCs were reinfused followed by i.v. application of a trifunctional antibody (TrAb) with specificities anti-EpCAMxanti-CD3. TrAbs are able to simultaneously bind tumor cells, T cells, and additionally FcgammaR type I and III+accessory cells via their Fc region. Side-effects during treatment were hematotoxicity, mucositis and gastrointestinal toxicity. TrAb treatment resulted in intermittent fever, chills, elevated liver enzymes, systemic inflammatory response syndrome and pulmonary leakage. With a follow-up period of more than 8 years the patient is still in remission (96+months). This case suggests the feasibility and efficacy of combining surgery, standard and HDCT, and subsequent immunotherapy in metastatic breast cancer. Further investigation of this approach is indicated in a subgroup of patients with oligometastatic breast cancer.

Adult↗
PubMed2005

Leukemia-derived dendritic cells can be generated from blood or bone marrow cells from patients with acute myeloid leukaemia: a methodological approach under serum-free culture conditions.

Functional dendritic cells (DC) are professional antigen-presenting cells (APC) and can be generated in vitro from healthy as well as from leukaemic cells from acute myeloid leukemia (AML) patients giving rise to APC of leukaemic origin-presenting leukaemic antigens. We describe the generation and characterization of DC from different mononuclear cell (MNC) fractions from 50 AML patients under different serum-free culture conditions, determine the optimal culture conditions and compare the results with that from 23 healthy donors. In parallel cultures, we compared DC harvests after 7- or 14-day culture, with total or adherent MNC or T-cell depleted MNC or peripheral blood (PB) or bone marrow-MNC (BM-MNC), thawn or fresh MNC, in Xvivo or CellGro serum-free media, +/-10% autologous plasma or +/-FL. In detail, we could show that AML-DC harvests were higher after 10-14 days culture (healthy DC: 7 days); total or adherent PB or BM-MNC fractions yield comparable DC counts, however, from magnetic cell sorting (MACS)-depleted MNC fractions or thawn MNC lower DC counts can be generated. Whereas the addition of FL increases the DC harvest, the addition of autologous plasma in many cases has inhibitory influence on DC maturation. CellGro and Xvivo media yield comparable DC counts. Optimal harvest of vital and mature DC from AML samples was obtained with a granulocyte/macrophage-colony stimulating factor, interleukin-4, FL and tumour necrosis factor-alpha-containing serum-free Xvivo medium after 10-14 days of culture (36/26% DC; 38/64% vital DC; 46/51% mature DC were generated from AML/healthy MNC samples). Surface marker profiles (e.g. costimulatory antigen expressing) of DC obtained from AML samples were comparable with that of healthy DC. The leukaemic derivation of AML-DC was demonstrated by the persistence of the clonal cytogenetic aberration in the DC or by coexpression of leukaemic antigens on DC. Autologous T-cell activation of leukaemia-derived DC was demonstrated in cases with AML. Autologous T cells proliferate and upregulate DC-contact-relevant antigens. We demonstrate that the generation of leukaemia-derived DC is feasable in AML under serum-free culture conditions giving rise to DC with comparable characteristics as healthy DC and offering an anti-leukaemia-directed immunotherapeutical vaccination strategy in AML.

Acute Disease↗
PubMed2005

Leukaemia-derived dendritic cells can be generated from blood or bone marrow cells from patients with myelodysplasia: a methodological approach under serum-free culture conditions.

Functional dendritic cells (DC) are professional antigen-presenting cells (APC) and can be generated in vitro from healthy as well as from leukaemic cells from AML patients giving rise to APC of leukaemic origin presenting leukaemic antigens. In a comparative methodological analysis of 50 AML samples, we could already show that leukaemia-derived DC can regularly be generated under serum-free culture conditions. In this study, we describe the generation and characterization of DC from different mononuclear cell (MNC) fractions from 24 myelodysplastic syndrome (MDS) patients under those different serum-free culture conditions, determine the optimal culture conditions and compare the results with that from 23 healthy donors. In parallel cultures, we compared DC harvests after 7- or 14-day culture, with total or adherent MNC or T-cell-depleted MNC or PB or BM-MNC, thawn or fresh MNC, in Xvivo or CellGro serum-free media, +/-10% autologous plasma or +/-FL. In detail, we could show that MDS-DC harvests compared to healthy DC were higher after 10- to 14-day culture; total or adherent PB or BM-MNC fractions yield comparable DC counts; however, from MACS-depleted MNC fractions or thawn MNC lower DC counts can be generated. Whereas the addition of FL increases the DC harvest, the addition of autologous plasma in many cases has inhibitory influence on DC maturation, CellGro and Xvivo media yield comparable DC counts. Optimal harvest of vital and mature DC from MDS samples was obtained with a GM-CSF, IL-4, FL and TNF-alpha containing serum-free Xvivo medium after 10-14 days of culture (18/26% DC; 54/64% vital DC; 59/51% mature DC were generated from MDS/healthy MNC samples). Surface marker profiles (e.g. costimulatory antigen expression) of DC obtained from MDS samples were comparable with that of healthy DC. The leukaemic derivation of MDS-DC was demonstrated by the persistence of the clonal cytogenetic aberration in the DC or by coexpression of leukaemic antigens on DC. Autologous T-cell activation of leukaemia-derived DC was demonstrated in cases with MDS. Autologous T cells proliferate and upregulate DC-contact-relevant antigens. We are the first who demonstrate that the generation of leukaemia-derived DC is feasible not only in AML but also in MDS under serum-free culture conditions giving rise to DC with comparable characteristics as healthy DC and offering an antileukaemia-directed immunotherapeutical vaccination strategy in AML and MDS.

Adult↗
PubMed2004

Reduced-intensity conditioning using TBI (8 Gy), fludarabine, cyclophosphamide and ATG in elderly CML patients provides excellent results especially when performed in the early course of the disease.

Allogeneic bone marrow or stem cell transplantation is a curative therapeutic option for chronic myelogenous leukemia. In order to decrease the toxicity of the procedure, the dosage of total body irradiation was reduced from 12 to 8 Gy and subsequently the dose of cyclophosphamide from 120 to 80 mg/kg. The purine analogue fludarabine, ATG, cyclosporine A and a short course of methotrexate were given for immune suppression. So far, 35 elderly CML patients with sibling and unrelated donors have been transplanted. Transplant-related mortality at day + 100 was 11%. After engraftment, all patients achieved a complete cytogenetic remission. Relapse occurred in 14% of the patients. The risk of relapse was significantly higher in those patients transplanted in second chronic or accelerated phase (P = 0.048). After a median follow-up of 30 months (range 12-62), 63% of the patients are alive. Those patients transplanted within the first year from diagnosis had an overall survival of 79% (P = 0.049), emphasizing the benefit of early transplantation. Stepwise reduction of conditioning intensity resulted in stable engraftment, low relapse rates and encouraging overall survival in this high-risk patient group.

Antilymphocyte Serum↗
PubMed2004

An update on graft-versus-host and graft-versus-leukemia reactions: a summary of the sixth International Symposium held in Schloss Ellmau, Germany, January 22-24, 2004.

The Sixth International Symposium on Graft-versus-Host and Graft-versus Leukemia Reactions was held in Schloss Ellmau (near Garmisch-Partenkirchen, Germany) between January 21 and 24, 2004. A total of 110 invited participants (scientists and clinicians working in the area of allogeneic stem cell transplantation) discussed current topics. Major topics of the 2004 meeting were: clinical results of donor lymphocyte infusions, basic biology, immunogenetics, function and clinical relevance of natural killer cells, haplo-identical stem cell transplantation, immune monitoring and immune modulation. Further highlights were: adoptive immunotherapy, vaccination and antibody-mediated strategies. As can be seen in the summaries of the individual presentations, important advances have occurred in our understanding of GVH and GVL reactions. Each session was followed by an animated discussion, which resulted in new ideas, insights and projects both for basic research and clinical transplantation. This year's symposium ('From Marrow Transplantation to Cell Therapy') was jointly organized by the Ludwigs-Maximilians-University of Munich (Sonderforschungsbereich 455), GSF (National Research Center for Environment and Health) and the EBMT Immunobiology Working Party. The organizers and authors of the conference proceedings would like to extend their gratitude to all participants for sharing their ideas, slides and manuscripts and making this event possible.

Graft vs Host Disease↗
PubMed2004

Canine long-term bone marrow culture neutrophil production and functionality.

This in vitro study has been conducted to determine the optimal experimental conditions under which to produce canine neutrophils in long-term bone marrow cultures (LTBMC), establish functional parameters of neutrophils obtained from LTBMC and peripheral blood and to ascertain whether these cells display physiological similarities. Our aim is to provide an experimental model, enabling a correlation between hemopoietic injury and neutrophil functionality. The authors demonstrate for the first time that canine neutrophils grown in cultures are able to produce oxyradicals capable of killing bacterial products. Moreover, culture-grown neutrophils contain gelatinase granules, a marker of terminal neutrophil differentiation, and express a specific surface antigen. The results described in this article illustrate the development of a dynamic system that mimics physiological hemopoiesis.

Adenosine Triphosphate↗
PubMed2002

Platelet flow cytometric findings in patients undergoing conditioning therapy for allogeneic hematopoietic stem cell transplantation.

The conditioning regimen preceding hematopoietic stem cell transplantation (HSCT) causes a rapid decrease in the platelet count and signs of disseminated intravascular coagulation, possibly indicating platelet activation. As impacts during the conditioning regimen may predict later transplantation-associated complications, we investigated changes in platelet membrane glycoproteins (GP) and the liberation of microparticles. Platelet receptors and granules of 49 patients undergoing HSCT were evaluated by flow cytometric analysis before and after the different phases of the conditioning regimen [chemotherapy, total body irradiation (TBI), therapy with antithymocyte globulin (ATG)] and final transplantation. Following chemotherapy a high surface expression of CD62P, a low mepacrine staining, and a reduced surface expression of CD42b (part of the GP Ib/V/IX complex) were found, indicating an irreversible activation of platelets. In addition, elevated levels of circulating microparticles were observed, which may reinforce the thrombosis risk in these patients. Treatment with ATG leads to an elevated surface expression of PAC-1 epitopes, which are neoepitopes appearing after activation of GP IIb/IIIa. However, a significant degranulation was not detectable, which may be the consequence of inhibitory influences on platelets during ATG-induced cytokine release syndrome. TBI and transplantation itself had no influence on platelets. This study was able to demonstrate activating effects on platelets by certain phases of the conditioning regimen in patients receiving HSCT. Chemotherapy, in particular, leads to a strong and irreversible platelet activation and a generation of microparticles, which may cause an increased thrombosis risk. Our findings underline the impact of platelets on the pathogenesis of hemostatic complications during HSCT.

Acyclovir↗
PubMed2002

Flow cytometric findings in platelets of patients following allogeneic hematopoietic stem cell transplantation.

Following allogeneic hematopoietic stem cell transplantation (HSCT) patients may have an increased bleeding tendency in spite of a normal platelet count. Moreover, an association between chronic graft-versus-host disease (cGVHD) and a thrombophilic state has been observed. Platelet receptors and granules from 27 patients following HSCT (13 without cGVHD, 14 with cGVHD) were evaluated by flow cytometric analysis and compared to 62 healthy controls. Platelets from HSCT patients stained weakly with mepacrine indicating a reduced content of dense bodies, whereas no significant degranulation reaction of alpha granules and lysosomes was detectable. In addition, a lower surface expression of GP Ia/IIa was observed, indicating an acquired thrombocytopathy. The surface receptors are activated in HSCT patients, which could be seen by the lower surface expression of GP Ib internalized during the activation process and elevated levels of LIBS-1 and PAC-1 antibody binding. Patients with cGVHD had a seven-fold increased ratio of microparticles. This study demonstrates platelet receptor and granule defects in patients following HSCT. The key role of platelets in HSCT-associated hemostatic disorders is underscored by the high levels of circulating microparticles in cGvHD patients which might explain the thrombophilic state in these patients.

Adult↗
PubMed2002

New concepts about graft-versus-host and graft-versus-leukaemia-reactions. A summary of the 5th International Symposium held in Munich, 21 and 22 March 2002.

The Fifth International Symposium on Graft-versus-Host and Graft-versus-Leukemia Reactions was held on 21 and 22 March 2002 in the University Hospital (Klinikum Grosshadern) of the University of Munich. As in previous years, it was dedicated to the encounter of scientists and clinicians involved in hematopoietic cell transplantation. This year's symposium focused on the characterization of stem cells potentially expanding the use of hematopoietic stem cells and on gene therapy. The immunology section dealt with mechanisms of tolerance, and the characterization of minor histocompatibility antigens presented by major histocompatibility molecules. Further important topics were cytokines and dendritic cells. In 1 and 1/2 days of intense work, the invited speakers, chairmen, authors and an active audience experienced an exciting exchange of ideas and collaboration. Again, new impulses were given for basic research and clinical transplantation. The authors would like to express their deep appreciation and thanks to all participants of this symposium.

Animals↗
PubMed2002

Nonmyeloablative stem cell transplantation in adults with high-risk ALL may be effective in early but not in advanced disease.

The feasibility of nonmyeloablative stem cell transplantation (NST) was evaluated in 22 adults with high-risk ALL. 16/22 patients had advanced disease and 11/22 had Ph+ ALL. Eleven patients received NST as first stem cell transplantation (SCT). Eleven patients had relapses after allogeneic or autologous SCT and underwent a salvage NST. 18/22 patients (82%) engrafted after NST. 13/16 patients (81%) with active disease reached complete remission (CR). 11 of 13 patients developed GVHD. After first NST 10/11 patients (91%) engrafted. Six of seven patients with active disease reached CR. Three of five relapsing patients reached subsequent CR after donor lymphocyte infusions, termination of immunosuppression or imatinib. Three of 11 patients (27%) are alive in CR 5 to 30 months after NST. Eight of 11 patients have died, 3/8 from leukemia and 5/8 from transplant-related causes. After salvage NST, 8/11 patients (73%) engrafted. Seven of nine patients with active disease reached CR. Only one of 11 patients transplanted, who was in CR before undergoing salvage NST is alive 19 months after NST. Five of 11 have died from leukemia, one of 11 after graft failure and four of 11 from transplant-related causes. Four of 22 patients (18%) are alive in CR 5, 14, 19 and 30 months after NST. NST is feasible in adults with high risk ALL. However, transplant-related mortality remains high and only patients transplanted in CR seem to have long-term disease-free survival.

Adult↗
PubMed2002

The detection of apoptosis in a human in vitro skin explant assay for graft versus host reactions.

AIMS: Keratinocyte apoptosis is a major pathogenic mechanism in dermal complications, such as graft versus host disease (GVHD), after allogeneic bone marrow transplantation. However, the mechanisms by which recipient target cells undergo apoptosis in GVHD are still unclear, but may result from DNA damage caused by chemotherapeutic agents and/or by direct cytokine action. The basis of this investigation was to correlate keratinocyte apoptosis with (1) the severity of graft versus host reactions (GVHR) in vitro and (2) the clinical grade (0--III) of GVHD. METHODS: Skin sections generated from an in vitro skin explant model for detecting experimental or clinically relevant GVHR were investigated for the detection of apoptotic nuclei using the terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) technique. This investigation also aimed to establish whether the TUNEL assay could be used as an additional, predictive method for the severity of GVHD before transplantation in potential patient/donor pairs given standard GVHD prophylaxis (cyclosporin A and methotrexate). RESULTS: By comparing mean values of apoptosis for each GVHR grade in a cohort of 83 retrospective skin sections it was shown that as the severity of GVHR increased there was a parallel increase in the percentage of apoptotic cells (p < 0.0001). However, the correlation between clinical GVHD grade II--III and overall keratinocyte apoptosis (> 2.6%) did not reach this degree of significance (chi(2): 4.2; degrees of freedom, 1; p = 0.04; Fisher's exact test: p = 0.06). CONCLUSIONS: The detection of apoptosis correlated with degree of GVHR using an in vitro assay and a higher degree of apoptosis tended to correlate with more severe GVHD. Further studies in a larger cohort of patients, using other methods to detect apoptosis in conjunction with the TUNEL assay, may give additional insight into the complex immunopathophysiology of GVHD.

Apoptosis↗