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SummaryThe broaden application of adoptive T-cell transfer has been constrained by the technical abilities to isolate and expand antigen-specific T cells potent to selectively kill tumor cells. With the recent progress in the design and manufacturing of cellular products, T cells used in the treatment of malignant diseases may be regarded as anticancer biopharmaceuticals. Genetical manipulation of T cells has given T cells desired specificity but also enable to tailor their activation and proliferation potential. Here, we summarize the recent developments in genetic engineering of T-cell-based biopharmaceuticals, covering criteria for their clinical application in regard to safety and efficacy. © 2014 S. Karger GmbH, Freiburg [ABSTRACT FROM AUTHOR]

Introduction: The transfer of allogeneic lymphocytes contained in a hematopoietic stem cell graft confers an immune-mediated antileukemic effect, termed the graft-vs-leukemia (GVL) effect. Graft-vs-host disease (GVHD), the most detrimental complication of allogeneic BMT, largely resides within the same lymphocyte population. Therefore, separation of GVL- and GVH-reactions is a long-standing goal of experimental studies dealing with allogeneic transplantation of hematopoietic stem cells.Materials and methods: The objective of the current study was to assess the potential of Th1- and Th2-type CD4+ T cells in mediating GVHD and GVL effects in a fully allogeneic murine transplant model. BALB/c (H-2d) mice were given a dose of A20 (H-2d, B-cell leukemia) cells two days prior to lethal total body irradiation (TBI) and transplantation of fully mismatched (C57BL/6, H-2b) T-cell depleted (anti-Thy1.2, CD90) bone marrow (TCD-BM) cells. Graded numbers of either unmanipulated, Th1- or Th2-polarized highly enriched CD4+ donor type T cells (106 or 107) were administered 2 h posttransplant. Infusion of 106 of unmanipulated, Th1-, or Th2-primed CD4+ T cells resulted in moderate GVHD-related mortality (40%, 50%, 10%) and significantly improved long-term survival (50%, 45%, 46% surviving the observation period of 120 days) as compared to animals receiving TCD-BM alone (18%).Results: The administration of 107 unmanipulated or Th1-type CD4+ T cells given shortly after transplantation led to death of all mice within 50 days due to fatal acute GVHD. In contrast, the adoptive transfer of 107 Th2-primed CD4+ T cells resulted in significant improvement of long-term survival (80%) compared to the TCD-BM group. This powerful GVL effect was associated with a substantially lower incidence of lethal acute GVHD (10%) if compared to the results of... [ABSTRACT FROM AUTHOR]

Endogenous danger signals are increasingly recognized in the pathogenesis of graft-versus-host disease (GVHD). Uric acid (UA) is a known danger signal and is released from injured cells during conditioning for allogeneic hematopoietic stem cell transplantation (HSCT), but its role in GVHD is unclear. Here, we retrospectively analyze 228 consecutive patients with malignant diseases undergoing HSCT from 10/10-HLA-matched donors. Low UA levels at the time of HSCT (day 0) were significantly associated with acute GVHD grades II-IV in univariate (HR 0.836, p = 0.0072) and multivariate analyses (HR 0.815, p = 0.0047). There was no significant association between UA levels and overall survival, non-relapse mortality, and relapse. This is the first report demonstrating a negative association between UA levels and acute GVHD. Due to the easy assessment and established pharmaceutical modification of UA, our findings are potentially clinically relevant. Confirmation in independent cohorts and further investigations into underlying mechanisms, such as reduced antioxidative capacity in hypouricemia, are warranted. [ABSTRACT FROM AUTHOR]

This review is intended to reflect upon the current status and perspectives of cell-based immunotherapy at a time when the promise of extensive pre-clinical research has been translated into encouraging clinical responses. However, some of these have also been complicated by significant adverse reactions. As the field moves towards definitive late stage trials, with a growing interest from pharmaceutical companies, we realize that novel cell therapy strategies pose questions that are familiar to traditional drug development, along with new considerations due to the potential of T cells to persist long term and to expand after adoptive transfer. These questions address the safety of the product, the efficacy, the mode of action, and the anticipation of risks. From different perspectives, we intend to address exciting opportunities and safety concerns in current concepts of cellular immunotherapy. [ABSTRACT FROM AUTHOR]

Infections of the central nervous system (CNS) are increasingly reported in patients with malignancies. Heavily immunocompromised patients like those after allogeneic stem cell transplantation (SCT) or previous T cell depleting treatment regimens (e.g. with fludarabine or alemtuzumab) are at highest risk for cerebral infections. The spectrum of causative organisms may vary greatly, depending on the underlying malignancy, its treatment and various other factors. Toxoplasma gondii and fungi are the leading causative organisms in patients after allogeneic SCT, but also viruses such as herpes simplex virus or JC virus may be detected in these patients. Definitive diagnosis of cerebral infection still remains a high challenge, although diagnostics have improved by the wide availability of imaging techniques and polymerase chain reaction in recent years. Novel therapeutic options are arising, particularly for fungal CNS infections. Here, we summarise aspects on epidemiology, clinical symptoms and prognosis of CNS infections in patients with malignancies. Additionally, we give an overview on the diagnostics and management of cerebral infections in these patients including evidence evaluation of efficacy of treatment. [ABSTRACT FROM AUTHOR]

Natural killer (NK) cells can lyse a variety of different tumour cells by exocytosis of perforin, subsequent binding of perforin to the target cell membrane and formation of lytic pores. Some tumour cells, however, are resistant to cellular cytotoxicity. Using the NK-resistant tumour cell lines ML-2, MONOMAC-1, RPMI and L540Cy, we demonstrated that activation of NK cells with interleukin 2 (IL-2) and IL-12 resulted in significant lysis of these tumour targets. To investigate the underlying mechanisms, we isolated the cytotoxic granules from non-activated and IL-2-/IL-12-activated NK cells and compared the killing of K562 leukaemia cells (sensitive to NK cell-mediated lysis) and ML-2 leukaemia cells (resistant to NK cell-mediated lysis). In contrast to K562 cells, which were easily killed by NK-cell granules, ML-2 cells were resistant to granules from non-activated NK cells. However, granules from NK cells activated with IL-2 and IL-12 were able to induce significant tumour cell lysis. Cell death of both K562 and ML-2 cells by granules from activated NK cells was completely blocked by anti-perforin antibodies, indicating that perforin mainly accounts for the lysis induced by NK granules. Comparing granules from non-activated and IL-2-/IL-12-activated NK cells, the increased cell death of ML-2 cells was caused by an improved binding of perforin to the target cell membrane. Functional assays, however, indicated that the differences in perforin binding were not as a result of an augmented production of perforin by activated NK cells. We conclude that activation of NK cells results in an increased binding of perforin and subsequent lysis of tumour cells. [ABSTRACT FROM AUTHOR]

Adoptive transfer of T cells genetically modified by TCRs or CARs represents a highly attractive novel therapeutic strategy to treat malignant diseases. Various approaches for the development of such gene therapy medicinal products (GTMPs) have been initiated by scientists in recent years. To date, however, the number of clinical trials commenced in Germany and Europe is still low. Several hurdles may contribute to the delay in clinical translation of these therapeutic innovations including the significant complexity of manufacture and non-clinical testing of these novel medicinal products, the limited knowledge about the intricate regulatory requirements of the academic developers as well as limitations of funds for clinical testing. A suitable good manufacturing practice (GMP) environment is a key prerequisite and platform for the development, validation, and manufacture of such cell-based therapies, but may also represent a bottleneck for clinical translation. The German Cancer Consortium (DKTK) and the Paul-Ehrlich-Institut (PEI) have initiated joint efforts of researchers and regulators to facilitate and advance early phase, academia-driven clinical trials. Starting with a workshop held in 2016, stakeholders from academia and regulatory authorities in Germany have entered into continuing discussions on a diversity of scientific, manufacturing, and regulatory aspects, as well as the benefits and risks of clinical application of CAR/TCR-based cell therapies. This review summarizes the current state of discussions of this cooperative approach providing a basis for further policy-making and suitable modification of processes. [ABSTRACT FROM AUTHOR]

We prospectively evaluated a multiplex real-time PCR assay (SeptiFast, SF) in a cohort of patients undergoing allo- BMT in comparison to an in-house PCR method ( IH- PCR). Overall 847 blood samples (mean 8 samples/patient) from 104 patients with haematological malignancies were analysed. The majority of patients had acute leukaemia (62%) with a mean age of 52 years (54% female). Pathogens could be detected in 91 of 847 (11%) samples by SF compared to 38 of 205 (18.5%) samples by BC, and 57 of 847 (6.7%) samples by IH- PCR. Coagulase-negative staphylococci (n=41 in SF, n=29 in BC) were the most frequently detected bacteria followed by Escherichia coli (n=9 in SF, n=6 in BC). Candida albicans (n=17 in SF, n=0 in BC, n=24 in IH- PCR) was the most frequently detected fungal pathogen. SF gave positive results in 5% of samples during surveillance vs in 26% of samples during fever episodes. Overall, the majority of blood samples gave negative results in both PCR methods resulting in 93% overall agreement resulting in a negative predictive value of 0.96 (95% CI: 0.95-0.97), and a positive predictive value of 0.10 (95% CI: −0.01 to 0.21). SeptiFast appeared to be superior over BC and the IH- PCR method. [ABSTRACT FROM AUTHOR]

The article reports on a study which investigated the impact of telomere length on the outcome of allogeneic stem cell transplantation (SCT) for patients with poor risk chronic lymphocytic leukaemia (CLL) based on the German CLL3X trial which included 100 patients. Topics covered include association of telomere length with clinical characteristics, and analysis of telomere length using quantitative polymerase chain reaction.

To expand the current knowledge about azacitidine (Aza) and donor lymphocyte infusions (DLI) as salvage therapy for relapse after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and to identify predictors for response and survival, we retrospectively analyzed data of 154 patients with acute myeloid leukemia (AML, n = 124), myelodysplastic (MDS, n = 28), or myeloproliferative syndrome (n = 2). All patients received a median number of 4 courses of Aza (range, 4 to 14) and DLI were administered to 105 patients (68%; median number of DLI, 2; range, 1 to 7). Complete and partial remission rates were 27% and 6%, respectively, resulting in an overall response rate of 33%. Multivariate analysis identified molecular-only relapse (hazard ratio [HR], 9.4; 95% confidence interval [CI], 2.0 to 43.5; P = .004) and diagnosis of MDS (HR, 4.1; 95% CI, 1.4 to 12.2; P = .011) as predictors for complete remission. Overall survival (OS) at 2 years was 29% ± 4%. Molecular-only relapse (HR, .14; 95% CI, .03 to .59; P = .007), diagnosis of MDS (HR, .33; 95% CI, .16 to .67; P = .002), and bone marrow blasts <13% (HR, .54; 95% CI, .32 to .91; P = .021) were associated with better OS. Accordingly, 2-year OS rate was higher in MDS patients (66% ± 10%, P = .001) and correlated with disease burden in patients with AML. In summary, Aza and DLI is an effective and well-tolerated treatment option for patients with relapse after allo-HSCT, in particular those with MDS or AML and low disease burden. The latter finding emphasizes the importance of stringent disease monitoring and early intervention. [ABSTRACT FROM AUTHOR]

Background: Gastrointestinal graft–versus-host disease (GvHD) is a potentially life-threatening complication after allogeneic stem cell transplantation (SCT). Since therapeutic options are still limited, a prophylactic approach seems to be warranted. Methods: In this randomised, double-blind-phase III trial, we evaluated the efficacy of budesonide in the prophylaxis of acute intestinal GvHD after SCT. The trial was registered at https://clinicaltrials.gov, number NCT00180089. Patients were randomly assigned to receive either 3 mg capsule three times daily oral budesonide or placebo. Budesonide was applied as a capsule with pH-modified release in the terminal ileum. Study medication was administered through day 56, follow-up continued until 12 months after transplantation. If any clinical signs of acute intestinal GvHD appeared, an ileocolonoscopy with biopsy specimens was performed. Results: The crude incidence of histological or clinical stage 3–4 acute intestinal GvHD until day 100 observed in 91 (n =48 budesonide, n =43 placebo) evaluable patients was 12.5% (95% CI 3-22%) under treatment with budesonide and 14% (95% CI 4-25%) under placebo (p = 0.888). Histologic and clinical stage 3–4 intestinal GvHD after 12 months occurred in 17% (95% CI 6-28%) of patients in the budesonide group and 19% (CI 7-32%) in the placebo group (p = 0.853). Although budesonide was tolerated well, we observed a trend towards a higher rate of infectious complications in the study group (47.9% versus 30.2%, p = 0.085). The cumulative incidences at 12 months of intestinal GvHD stage >2 with death as a competing event (budesonide 20.8% vs. placebo 32.6%, p = 0.250) and the cumulative incidence of relapse (budesonide 20.8% vs. placebo 16.3%, p = 0.547) and non-relapse mortality (budesonide 28% (95% CI 15-41%) vs. placebo 30% (95% CI 15-44%), showed no significant difference within the two groups (p = 0.911). The trial closed after 94 patients were enrolled because of slow accrual. Within the limits of the final sample size, we were unable to show any benefit for the addition of budesonide to standard GvHD prophylaxis. Conclusions: Budesonide did not decrease the occurrence of intestinal GvHD in this trial. These results imply most likely that prophylactic administration of budenoside with pH-modified release in the terminal ileum is not effective. [ABSTRACT FROM AUTHOR]

Background: After hematopoietic stem cell transplantation (HSCT) T- and B-cell reconstitution from primary lymphoid organs are a prerequisite for an effective early lymphocyte reconstitution and a long-term survival for adult patients suffering from acute leukemia. Here, we asked whether quantification of T cell receptor excision circle, (TREC) and kappa-deleting recombination excision circle (KREC) before and within six month after allogeneic HSCT could be used to measure the thymic and bone marrow outputs in such patients. Methods: We used a duplex real time PCR assay to quantify the absolute copy counts of TREC and KREC, and correlated the data with absolute cell counts of CD3+CD4+ T-cell and CD19+ B-cell subsets determined by flow cytometry, respectively. Results: By comparing two recently proposed naïve T cell subsets, CD31+ naive and CD31- naive T cells, we found a better correlation for the CD31+ subset with TREC level post alloHSCT, in line with the assumption that it contained T cells recently derived from the thymus, indicating that TREC levels reflected real thymic de novo production. Transitional as well as naïve B cells highly correlated with KREC levels, which suggested an association of KREC levels with ongoing bone marrow B cell output. CD45RO+ memory T cells and CD27+ memory B cells were significantly less correlated with TREC and KREC recovery, respectively. Conclusion: We conclude that simultaneous TREC/ KREC quantification is as a suitable and practicable method to monitor thymic and bone marrow output post alloHSCT in adult patients diagnosed with acute leukemia. [ABSTRACT FROM AUTHOR]

The purpose of this analysis was to provide 6-year follow-up of the CLL3X trial, which studied reduced-intensity allogeneic hematopoietic stem cell transplantation (HSCT) in patients with poor-risk chronic lymphocytic leukemia (CLL), and to investigate the effect of TP53, SF3B1, and NOTCH1 mutations on HSCT outcome. For 90 allografted patients, 6-year overall survival (OS) was 58% and 6-year event-free survival (EFS) was 38%. TP53, SF3B1, and NOTCH1 mutations were found in 30%, 26%, and 14% of the trial population, respectively. By univariate and multivariate analyses, the mutational status of the TP53, SF3B1, and NOTCH1 genes had no significant effect on OS and EFS. Studies of minimal residual disease confirmed durability of CLL eradication in mutated patients. We conclude that HSCT can provide long-term disease control in patients with poor-risk CLL independent of the presence of TP53, SF3B1, and NOTCH1 mutations. The trial has been registered at the US National Cancer Institute as #EU-20554, NCT00281983. [ABSTRACT FROM AUTHOR]

Patients with allogeneic stem cell transplantation (SCT) have a high risk of invasive fungal infections (IFIs) even after neutrophil regeneration. Immunological aspects might play a very important role in the IFI development in these patients. Some data are available supporting the identification of high-risk patients with IFI for example patients receiving stem cells from TLR4 haplotype S4 positive donors. Key defense mechanisms against IFI include the activation of neutrophils, the phagocytosis of germinating conidia by dendritic cells, and the fight of the cells of the innate immunity such as monocytes and natural killer cells against germlings and hyphae. Furthermore, immunosuppressive drugs interact with immune effector cells influencing the specific fungal immune defense and antimycotic drugs might interact with immune response. Based on the current knowledge on immunological mechanism in Aspergillus fumigatus, the first approaches of an immunotherapy using human T cells are in development. This might be an option for the future of aspergillosis patients having a poor prognosis with conventional treatment. [ABSTRACT FROM AUTHOR]

Based on clinical activity in phase 2 studies, lenalidomide was evaluated in a phase 2/3 study in patients with relapsed/refractory chronic lymphocytic leukemia (CLL). Following tumor lysis syndrome (TLS) complications, the protocol was amended to a phase 1 study to identify the maximum tolerated dose-escalation level (MTDEL). Fifty-two heavily pretreated patients, 69% with bulky disease and 48% with high-risk genomic abnormalities, initiated lenalidomide at 2.5 mg/day, with dose escalation until the MTDEL or the maximum assigned dose was attained. Lenalidomide was safely titrated to 20 mg/day; the MTDEL was not reached. Most common grade 3-4 adverse events were neutropenia and thrombocytopenia; TLS was mild and rare. The low starting dose and conservative dose escalation strategy resulted in six partial responders and 30 patients obtaining stable disease. In summary, lenalidomide 2.5 mg/day is a safe starting dose that can be titrated up to 20 mg/day in patients with CLL. [ABSTRACT FROM AUTHOR]

Extramedullary relapses after allogeneic stem cell transplantation, especially within the central nervous system (CNS), are not only difficult to treat but also associated with poor outcome. Although the graft-versus-leukemia (GvL) effect is nowadays accepted and well documented, it remains controversial whether one can make use of GvL effects in immunological-restricted areas ('sanctuary sites') like the central nervous system. Here, we present data of three hematological patients suffering from isolated CNS relapse of CML or AML after allogeneic stem cell transplantation. Patients received in addition to chemotherapy intrathecal infusions of donor lymphocytes by CD14 depletion of peripheral blood mononuclear cells from the correspondent allogeneic donor. Referring to an observation period of maximum 17 months no immediate or delayed side effects could be detected. [ABSTRACT FROM AUTHOR]

BACKGROUND: The bacterial microflora aggravates graft-versus-host-disease (GvHD) after allogeneic stem cell transplantation, but the underlying mechanisms of manifestations of intestinal GvHD (iGvHD) in the gut remain poorly understood. AIM: To analyse the gut flora composition and the impact of bacterial sensing via Toll-like receptors (TLRs) in iGvHD. METHODS: By mimicking clinical low-intensity conditioning regimens used in humans, a novel irradiation independent, treosulfan and cyclophosphamide-based murine allogeneic transplantation model was established. A global survey of the intestinal microflora by cultural and molecular methods was performed, the intestinal immunopathology in TLR-deficient recipient mice with iGvHD investigated and finally, the impact of anti-TLR9 treatment on iGvHD development assessed. RESULTS: The inflammatory responses in iGvHD were accompanied by gut flora shifts towards enterobacteria, enterococci and Bacteroides/Prevotella spp. Analysis of iGvHD in MyD88-/-, TRIF-/-, TLR2/4-/-, and TLR9-/-recipient mice showed that bacterial sensing via TLRs was essential for iGvHD development. Acute iGvHD was characterised by increasing numbers of apoptotic cells, proliferating cells, T cells and neutrophils within the colon. These responses were significantly reduced in MyD88-/-, TLR2/4-/-, TRIF-/-and TLR9-/-mice, as compared with wild-type controls. However, TRIF-/-and TLR2/4-/-mice were not protected from mortality, whereas TLR9-/-mice displayed increased survival rates. The important role of TLR9-mediated immunopathology was independently confirmed by significantly reduced macroscopic disease symptoms and colonic apoptosis as well as by reduced T-cell and neutrophil numbers within the colon after treatment with a synthetic inhibitory oligonucleotide. CONCLUSIONS: These results emphasise the critical role of gut microbiota, innate immunity and TLR9 in iGvHD and highlight anti-TLR9 strategies as novel therapeutic options. [ABSTRACT FROM AUTHOR]

Abstract: We analyzed karyotype stability in 22 patients with acute leukemia at relapse or disease progression after allogeneic stem cell transplantation (allo-SCT). Karyotypes before and at relapse after allo-SCT were different in 15 patients (68%), the most frequent type being clonal evolution either alone or combined with clonal devolution (13 patients). Patients with and without a karyotype change did not differ significantly in overall survival (OS) (median, 399 vs. 452 days; P = 0.889) and survival after relapse (median, 120 vs. 370 days; P = 0.923). However, acquisition of additional structural chromosome 1 abnormalities at relapse after allo-SCT occurred more frequently than expected and was associated with reduced OS (median, 125 vs. 478 days; P = 0.008) and shorter survival after relapse (median, 37 vs. 370 days; P = 0.002). We identified a previously undescribed clonal evolution involving t(15;17) without PML-RARA rearrangement in an AML patient. We conclude that a karyotype change is common at relapse after allo-SCT in acute leukemia patients. Moreover, our data suggest that additional structural chromosome 1 abnormalities are overrepresented at relapse after allo-SCT in these patients and, in contrast to a karyotype change per se, are associated with reduced OS and shorter survival after relapse. [Copyright &y& Elsevier]

Presents the case of an 18-year-old man who was admitted for allogeneic stem cell transplantation in first remission of acute myeloid leukemia. Physical examination of a patient which reveals air embolism due to an open lid of the jugular vein central line; Use of computed tomography in identifying cause and nature of the disease; Discharge of patient from hospital after the transplantation.

Background: In patients treated with rituximab and alemtuzumab for lymphomas or CLL, antibody-dependent cellular cytotoxicity (ADCC) is a major mechanism of action. Therefore, assessment of ADCC is mandatory to understand the complex mechanisms leading to the anti-lymphoma effects of monoclonal antibodies (mAb). Due to methodical difficulties, little is yet known about the relevant cell subpopulations and effector mechanisms leading to tumor lysis in ADCC. Methods: We used a novel flow cytometric assay that detects CD107a as a marker for NK-cell degranulation to characterize and quantify peripheral blood natural killer (NK) cells mediating ADCC in vitro and in vivo. Results: We observed specific and dose-dependent NK-cell activation after administration of rituximab and alemtuzumab. The number of degranulating NK cells was closely related to the concentration of mAb and the effector:target ratio. We were able to quantify and characterize the peripheral blood NK cells mediating ADCC. The majority of degranulating NK cells had the phenotype: CD56dim, CD69+, NKG2D+, NKp30−, NKp46−, and CD94−. Furthermore, we found that the CD107a assay can also visualize ADCC under clinical conditions as we observed increased numbers of NK cells degranulating in response to CD20+ lymphoma cell lines in patients with non-Hodgkin''s lymphoma treated with rituximab. Conclusions: We were able to quantify and characterize NK cells mediating ADCC with a new and feasible method. The CD107a assay may be useful for predicting treatment responses of individual patients and may help find the optimal dosage and timing for treatment with mAb. [Copyright &y& Elsevier]

Acute graft- versus-host disease (aGVHD) occurs in up to 80% of patients who undergo allogeneic stem cell transplantation (SCT) and contributes significantly to transplant-related mortality (TRM). We conducted a prospective phase II trial to assess the efficacy and feasibility of treating steroid-refractory aGVHD with basiliximab, a chimaeric monoclonal antibody directed against the alpha chain of the interleukin-2 (IL-2) receptor. Basiliximab was administered intravenously at a dose of 20 mg on days 1 and 4. Twenty-three patients were enrolled between October 1999 and July 2004. We found a primary overall response rate of 82·5% with four patients (17·5%) showing a complete response and 15 patients (65%) a partial response. Six patients were again treated successfully with an IL-2 receptor antagonist because of recurrence of aGVHD. The rates of infections, chronic GVHD, malignancy recurrence and 1-year TRM following immunosuppression with basiliximab were comparable with those found with other treatment modalities for aGVHD. We conclude that basiliximab is efficient and feasible for steroid-refractory aGVHD and merits further evaluation. [ABSTRACT FROM AUTHOR]

Summary. Idiotype (Id) vaccination provides an interesting immunotherapeutic strategy against B-cell lymphomas. In multiple myeloma (MM), however, the therapeutic efficacy of Id vaccination has been disappointing. In an attempt to improve the antitumoral potential, we added granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin 2 (IL-2) to the protocol. Balb/c mice were inoculated i.p. (d 2) with different doses (1–5 × 105 ) of HOPC myeloma cells secreting the IgHOPC Id protein. Two days later, animals were injected with 10 000 U GM-CSF i.p. for 6 d consecutively (d 0–5). On d 5 and 11, myeloma-specific immunoglobulin (IgHOPC ) was administered i.p. together with incomplete Freund adjuvans followed by IL-2 (2 × 10 000 U/d; i.p) for 10 d (d 5–14). In animals inoculated with 105 myeloma cells, treatment with IL-2 given as a single agent prolonged the median survival time (MST, 67 d) when compared with the tumour control group (MST 48 d), whereas GM-CSF did not elicit any survival benefit (MST 49 d). Complete tumour rejection could be achieved in 27% (4/15) by the combination of Id vaccination and GM-CSF. Additional treatment with IL-2 further increased antimyeloma activity. In this case, 59% of the animals showed no signs of tumour recurrence. In mice with high tumour burden (5 × 105 ), no treatment modality achieved long-term survivors. Both natural killer (NK) cells and CD8+ T cells may be involved in the antitumoural immune response. These data provide evidence for the combined use of GM-CSF and IL-2 to enhance the therapeutic effectiveness of clinical cancer vaccination protocols. [ABSTRACT FROM AUTHOR]

Summary. Idiotype (Id) vaccination provides an innovative treatment modality against B-cell malignancies. In multiple myeloma patients, however, the antitumoral potential of this immunotherapeutic concept is limited. In an attempt to improve the therapeutic effectiveness of Id vaccination, we added Flt3 ligand (Flt3-L) and interleukin 2 (IL-2) to the protocol. Balb/c mice were inoculated i.p. (d -2) with different doses (1–5 × 105 ) of HOPC myeloma cells, secreting the IgHOPC Id-protein. Two days later, animals were treated with Flt3-L (10 µg per mouse/d, given i.p) for 10 consecutive days (d 0–9). On d 5 and d 11, myeloma-specific immunoglobulin (IgHOPC ) was administered s.c., together with incomplete Freund adjuvans (IFA) followed by the administration of IL-2 (2 × 10·000/d given i.p) for 10 d (d 5–14). Whereas IgHOPC , Flt3-L or IL-2, given alone, did not elicit long-term survival, the combination of IL-2 or Flt3-L with Id vaccination achieved a complete tumour rejection in 27% and 41% of mice respectively. However, the most powerful antimyeloma effects were induced by Flt3-L + Id vaccination + IL-2: 81% of the treated animals experienced long-term survival (> 180 d). Both natural killer (NK) cells and CD8+ T cells may be involved in the antitumoral immune response. These data suggest that the combination of Flt3-L and IL-2 can be used to enhance the therapeutic effectiveness of clinical cancer vaccination protocols. [ABSTRACT FROM AUTHOR]

Although ATG is frequently used in hematopoietic stem cell transplantation and solid organ transplantation, little is known on its effects on NK cells, which mediate important functions in post-transplantation immunology. We incubated peripheral blood lymphocytes of healthy donors with Thymoglobulin, Lymphoglobulin or ATG-Fresenius. Cell death and apoptosis of NK cells and T cells were determined by flow cytometry using propidium iodide and Annexin V. As expected, there were no significant differences between the different ATGs regarding their T cell toxicity. Surprisingly, we found profound differences between the different ATGs regarding their impact on NK cells: In clinically relevant concentrations Lymphoglobulin had less toxic effects on NK cells as compared to Thymoglobulin or ATG-Fresenius: the median percentages of apoptotic or necrotic NK cells in response to 1 μg/ml Lymphoglobulin, ATG-Fresenius and Thymoglobulin were 2%, 35% and 38%, respectively (p<0.001). This is the first report of differential effects of different ATGs on NK cells. Lymphoglobulin appears to be superior to Thymoglobulin or ATG Fresenius regarding the preservation of NK cell mediated immunity. Randomized trials addressing the impact of different ATGs on lymphocyte subpopulalions in the clinical setting are urgently warranted. [ABSTRACT FROM AUTHOR]

Background: Gastrointestinal graft-versus-host disease (GvHD) is a potentially life-threatening complication after allogeneic stem cell transplantation (SCT). Since therapeutic options are still limited, a prophylactic approach seems to be warranted.Methods: In this randomised, double-blind-phase III trial, we evaluated the efficacy of budesonide in the prophylaxis of acute intestinal GvHD after SCT. The trial was registered at https://clinicaltrials.gov, number NCT00180089.Results: The crude incidence of histological or clinical stage 3-4 acute intestinal GvHD until day 100 observed in 91 (n =48 budesonide, n =43 placebo) evaluable patients was 12.5% (95% CI 3-22%) under treatment with budesonide and 14% (95% CI 4-25%) under placebo (p = 0.888). Histologic and clinical stage 3-4 intestinal GvHD after 12 months occurred in 17% (95% CI 6-28%) of patients in the budesonide group and 19% (CI 7-32%) in the placebo group (p = 0.853). Although budesonide was tolerated well, we observed a trend towards a higher rate of infectious complications in the study group (47.9% versus 30.2%, p = 0.085). The cumulative incidences at 12 months of intestinal GvHD stage >2 with death as a competing event (budesonide 20.8% vs. placebo 32.6%, p = 0.250) and the cumulative incidence of relapse (budesonide 20.8% vs. placebo 16.3%, p = 0.547) and non-relapse mortality (budesonide 28% (95% CI 15-41%) vs. placebo 30% (95% CI 15-44%), showed no significant difference within the two groups (p = 0.911). The trial closed after 94 patients were enrolled because of slow accrual. Within the limits of the final sample size, we were unable to show any benefit for the addition of budesonide to standard GvHD prophylaxis.Conclusions: Budesonide did not decrease the occurrence of intestinal GvHD in this trial. These results imply most likely that prophylactic administration of budenoside with pH-modified release in the terminal ileum is not effective. [ABSTRACT FROM AUTHOR]