Jürgen Finke

Epithelial Tissue Chimerism after Human Hematopoietic Cell Transplantation Is a Real Phenomenon

Bone marrow transplantation in animals has been shown to generate epithelial populations, a phenomenon that has also recently been suggested to take place after human hematopoietic cell transplantation. However, reports in humans are not conclusive because they still leave open the possibility that the identified donor-derived cells are not epithelial cells but intraepithelial lymphocytes. Here, we demonstrate that donor-derived CD45(+) hematopoietic cells in close contact with epithelial tissue may be falsely characterized as donor-derived epithelial cells if the three-dimensional structure of the tissue is not considered and the hematopoietic markers are not examined. By using a rigorous three-dimensional analysis on single sections of colon biopsies triple stained with donor-specific, epithelial-specific, and hematopoietic-specific markers we demonstrate that chimerism of colon epithelium is a real phenomenon occurring constantly after human hematopoietic cell transplantation. We exclude horizontal DNA transfer or cell fusion as the underlying mechanism of our findings. Tissue damage enhances the engraftment of the donor-derived epithelial cells. The physiological and therapeutical role of the donor-derived epithelial cells after human hematopoietic cell transplantation needs further investigation. However, their identification requires stringent and unequivocal detection systems.

Reduced-toxicity conditioning with fludarabine, BCNU, and melphalan in allogeneic hematopoietic cell transplantation: particular activity against advanced hematologic malignancies

Toxicity-reduced conditioning is being used for allogeneic stem cell transplantation in older and/or comorbid patients. We report on the treatment of 133 patients (median age: 55.6 years [23-73 years]) with acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS; n = 81), myeloproliferative syndromes (MPS; n = 20), and lymphoid malignancies (n = 32) using conditioning with FBM: fludarabine (5 x 30 mg/m(2)), 1,3-bis(2-chloroethyl)-1-nitrosourea (or carmustine, BCNU; 2 x 200 mg/m(2)), and melphalan (140 mg/m(2)). Patients 55 years or older received fludarabine with reduced BCNU (2 x150 mg/m(2)) and melphalan (110 mg/m(2)). After engraftment, chimerism analyses revealed complete donor hematopoiesis in 95.7% of patients. With a median follow-up of 58.5 months, 3- and 5-year overall survival (OS) was 53.0% and 46.1%, event-free survival (EFS) was 46.4% and 41.9%. No significant differences in OS and EFS were evident considering disease status (early vs advanced), patient age (<55 vs> or =55 years), or donor type (related vs unrelated) in univariate and multivariate analyses. The cumulative 5-year incidence of death due to relapse was 20.1%. Nonrelapse mortality (NRM) after 100 days and 1 year was 15.8% and 26.3%. Among patients with AML/MDS, advanced cases (n = 64, including 61 with active disease) showed an OS of 44.6% and 42.4% after 3 and 5 years, respectively. Therefore, FBM conditioning combines effective disease control with low NRM.

Prognosis of patients with primary central nervous system lymphoma after high-dose chemotherapy followed by autologous stem cell transplantation

High-dose chemotherapy followed by autologous stem cell transplantation has been shown to be feasible and highly effective in newly diagnosed primary central nervous system lymphoma. In this retrospective multicenter study, we investigated prognosis and baseline risk factors in patients with primary central nervous system lymphoma who underwent this treatment approach. We retrospectively analyzed 105 immunocompetent patients with primary central nervous system lymphoma who underwent high-dose chemotherapy followed by autologous stem cell transplantation with or without whole brain radiotherapy as first-line consolidation treated at 12 German centers between 1997 and 2011. We estimated survival rates and investigated the impact of age, performance status, serum lactate dehydrogenase level, and deep brain involvement on overall and progression-free survival. Patients were additionally categorized into three prognostic groups according to the Memorial Sloan Kettering Cancer Center prognostic model. After a median follow up of 47 months, median progression-free survival and overall survival was reached after 85 and 121 months; 2- and 5-year survival rates were 82% and 79%, respectively. The Memorial Sloan Kettering Cancer Center prognostic model did not predict survival. Only age revealed some evidence of prognostic relevance. Overall response rate was 95%; of those patients with progressive disease before high-dose chemotherapy, 7 of 20 achieved ongoing complete remission after therapy without whole brain radiation therapy. Transplantation-associated mortality was 2.8%. High-dose chemotherapy followed by autologous stem cell transplantation is a highly effective and safe treatment modality for selected primary central nervous system lymphoma patients. Superiority compared to standard chemotherapy still warrants further investigation.

Successful treatment of severe acute intestinal graft-versus-host resistant to systemic and topical steroids with alemtuzumab.

Development of severe steroid-resistant acute graft-versus-host disease (GVHD) after allogeneic hematopoietic cell transplantation (HCT) is associated with poor outcome. The humanized monoclonal antibody alemtuzumab was shown to be effective in GVHD prophylaxis in conditioning regimens before allogeneic HCT. We evaluated the efficacy and safety of alemtuzumab in 20 patients with histologically confirmed steroid refractory grade III and IV intestinal GVHD after related and unrelated HCT. Overall response rate was 70%, with complete response in 35%. Despite the severe grade of GVHD in our patients, the median survival of 280 days and 1-year overall survival (OS) of 50% were superior or comparable to those associated with other treatment options. Cytomegalovirus (CMV) reactivation, bacterial infection, and invasive aspergillosis were frequent complications; however, infection was not a significant predictor for survival. These data suggest that treatment with alemtuzumab has favorable activity in severe intestinal GVHD after allogeneic HCT, but emphasize the importance of careful monitoring and anti-infectious supportive care.

Prognostic Factor and Quality of Life Analysis in 160 Patients Aged ≥60 Years with Hematologic Neoplasias Treated with Allogeneic Hematopoietic Cell Transplantation

Toxicity-reduced conditioning is a curative treatment option for medically compromised or elderly patients ineligible for myeloablative hematopoietic cell transplantation (HCT). The aim of this study was to detect prognostic factors for overall survival (OS) and to evaluate quality of life (QOL) in a large homogeneous cohort of 160 consecutive patients aged > or =60 years treated with allogeneic HCT. We evaluated age, sex, performance status, comorbidities, pulmonary function, lactic dehydrogenase concentration, type of donor, disease status, CD34(+) cells transplanted, cytomegalovirus status, time from diagnosis to HCT, and the development of acute and chronic graft-versus-host disease (GVHD). All patients who survived for > or =6 months (n = 79) were asked to complete a QOL survey. All patients (median age, 64.7 years; range, 60.1-76 years) received pretransplantation conditioning with fludarabine, BCNU, and melphalan. With a median follow-up of 35 months, the 1-year OS was 62.4% and 3-year OS was 47.4%. Multivariate analysis revealed compromised performance status as the most significant negative prognostic parameter for OS (P < .003), whereas male donor (P = .008) and chronic GVHD (P = .024) were associated with better OS. The 89% of survivors who returned the QOL questionnaire rated their global QOL as good-to-excellent despite impaired functional capabilities and such symptoms as fatigue, dyspnea, and loss of appetite. The main prognostic factor was performance status, not age. Our data suggest that toxicity-reduced conditioning offers a chance for enhanced OS with an adequate QOL.

A Novel GVHD-Prophylaxis with Low-Dose Alemtuzumab in Allogeneic Sibling or Unrelated Donor Hematopoetic Cell Transplantation: The Feasibility of Deescalation

Prophylaxis of acute graft-versus-host disease (aGVHD), while maintaining the graft-versus-leukemia (GVL)/lymphoma effect and preventing severe infectious diseases, remains the main challenge in allogeneic hematopoetic cell transplantation (allo-HCT). To evaluate this, we examined the feasibility of deescalating the dose of alemtuzumab (MabCampath) in combination with cyclosporine (CsA) as the sole GVHD-prophylaxis in patients after fludarabine (Flu)-based reduced-intensity conditioning (RIC) in an observational cohort study. We included 127 consecutive patients (median age 63 years) with an unrelated (UD; n=69) or related donor (SIB; n=58) after their first transplantation, mostly presenting with advanced disease. The first 30 patients received 20 mg/day on day -2 and -1 (40 mg), the following 48 patients 10 mg/day on day -2 and -1 (20 mg), and the last 49 patients 10 mg on day -1 (10 mg) alemtuzumab intravenous (i.v.) prior to transplant. We observed no statistical differences comparing the 40 mg, 20 mg, or 10 mg dose groups, in terms of cumulative incidences of aGVHD grade III-IV 7% (confidence interval [CI] 95%; 1-51), 12% (1-40), 6% (1-40), extensive chronic GVHD (cGVHD) 24.4% (3.3-55.8), 17% (2.5-42), and 14.2% (1.5-41.5) and of aGVHD grade II-IV 7 % (0-51.5), 29% (11.9-49.1), 21% (15.3-43.1), respectively. The difference between the 20-mg and 40-mg groups was significant for aGVHD grade II-IV(P < .05). In conclusion, we demonstrate the feasibility of reducing the dose of alemtuzumab as GVHD-prophylaxis to 10 mg absolute in combination with CsA only for UD transplantation in particular.

Rabbit anti T-lymphocyte globulin induces apoptosis in peripheral blood mononuclear cell compartments and leukemia cells, while hematopoetic stem cells are apoptosis resistant.

Polyclonal anti-T-lymphocyte globulins (ATG) are used in allogeneic stem cell transplantation (SCT) for the prophylaxis of graft versus host disease (GVHD) by in vivo T cell depletion. In this study we investigated the complement independent induction of apoptosis by rabbit ATG in peripheral blood mononuclear cell (PBMNC) compartments and hematopoetic stem cells (HSC). We also detected antileukemic activity of ATG by measuring apoptosis in myeloid and lymphatic leukemia cell lines and primary leukemia cells. We found ATG to induce apoptosis in T-lymphocytes (CD4(+), CD8+), B-lymphocytes (CD20+), natural killer (NK)-cells (CD56(+)), and monocytes (CD14(+)). HSC, in contrast, were apoptosis resistant and could be growth stimulated by low-dose ATG in the presence of bystander cells. The human leukemia cell lines Jurkat, Daudi, DG-75 (lymphoblastic), and K562, HL-60, KG1, and U937 (myeloblastic) underwent ATG-induced apoptosis, whereas the NK-cell line YT was resistant. Primary leukemia cells from 6 investigated patients with acute lymphoblastic leukemia, 9 of 10 patients with chronic lymphocytic leukemia, and 4 of 8 patients with acute myeloblastic leukemia underwent ATG-induced apoptosis. We conclude apoptosis induction in all PBMNC compartments contributes to GVHD prophylaxis. ATG might support engraftment. Finally, antileukemic activity of ATG could positively influence the transplantation outcome.

Stem cell plasticity: the debate begins to clarify.

The stem cell story begins with the recognition of the regenerative powers of the head of the Lernean Hydra and the human liver (Prometheus) by the ancient Greeks. In modern times, the adult human stem cell has been epitomized by the hematopoietic stem cell in the bone marrow. More recently, bone marrow derived cells were reported to contribute to nonhematopoietic organs, suggesting a level of plasticity not previously expected. However, other reports failed to repeat some of these results, resulting in a heated debate on the plasticity of adult stem cells that has crossed over into the public domain and become a matter of political impact on the use of embryonic vs adult stem cells for organ regeneration or gene therapy. This review discusses the current status of the “plasticity” debate and presents existing data on detection methodology, underlying mechanisms, physiological implications, and clinical significance.

Genome-wide Profiling in AML Patients Relapsing after Allogeneic Hematopoietic Cell Transplantation

Molecular pathogenesis of relapse after allogeneic hematopoietic cell transplantation is poorly understood. Data regarding relapse mechanisms after transplantation is scarcely available. We investigated genomic aberrations (GAs) in 21 patients undergoing related and unrelated HLA-matched transplantation in leukemic blasts before transplant and at relapse after transplantation. We found a higher number of GAs after transplantation, suggesting increased genomic instability during relapse. Two of 21 patients showed a large homozygous region spanning the whole HLA-locus on chromosome 6p in the relapse sample. In both patients sequence-based HLA typing of the blasts revealed a loss of the patient-specific allele at the mismatched locus leading to homozygosity for the HLA haplotype shared by the patient and the donor. In addition, GAs were found in critical regions such as 12p13, 13q12.2, and 17p13. Our results suggest that escape from immunologic surveillance may be a relevant mechanism of relapse after transplantation in patients with GAs on chromosome 6p. A combination of continuous immunologic pressure mediated by donor T cells and clonal evolution of myeloid leukemia may result in acquired GAs after transplantation.

18F-FDG PET Is an Independent Outcome Predictor in Primary Central Nervous System Lymphoma

Primary central nervous system (CNS) lymphoma is an aggressive non-Hodgkin lymphoma with poor prognosis. We evaluated pretreatment 18F-FDG PET as a prognostic marker in primary CNS lymphoma. Methods: Forty-two immunocompetent patients with newly diagnosed primary CNS lymphoma who underwent pretreatment 18F-FDG PET were retrospectively analyzed. Baseline status and response to treatment were evaluated by MR imaging. Tumor maximum standardized uptake values were assessed by volume-of-interest analyses using an automatic isocontour definition. A 10-step semiquantitative visual rating system (metabolic imaging lymphoma aggressiveness scale, or MILAS) was used to assess primary CNS lymphoma metabolism as a marker of clinical aggressiveness. Logistic regression, log-rank testing, and multivariable Cox regression were used to investigate the association between 18F-FDG uptake and tumor response and survival. Results: Mean maximum standardized uptake value correlated linearly with MILAS. The distribution of patients according to MILAS (0–9) was 0%, 28.6%, 23.8%, 21.4%, 11.9%, 4.8%, 7.1%, 0%, 0%, and 2.4%. There was no correlation between MILAS and response to treatment. Respective 2- and 5-y survival rates were 52% and 32% for progression-free survival (PFS) and 64% and 50% for overall survival (OS). A cutoff at MILAS 3 was a good separator for PFS (median: 54.7 mo [≤3], 3.8 mo [>3], P = 0.0272) and OS (median: not reached [≤3], 13.8 mo [>3], P = 0.131). In multivariable analyses, increasing MILAS was significantly associated with shorter PFS (hazard ratio, 1.49, P = 0.006) and OS (hazard ratio, 1.43, P = 0.018). Conclusion: Increased pretreatment 18F-FDG uptake may offer new opportunities for baseline risk evaluation in untreated primary CNS lymphoma.