Search

Patients were transplanted with a median time to allo-HCT of 15.1 months (IQR, 9.8-27.9) for CEL, NOS patients, and 22.2 months (IQR, 11.5-55.8; I p i = 0.01) for HES. Helbig et al. reported on 10 patients with CEL, NOS with a median age of 62 (23-73 years), frequently with an aggressive clinical course, five of whom developed acute transformation within two years from the time of diagnosis.6 Here, only one patient in the chronic phase successfully underwent allo-SCT. Keywords: allogeneic stem cell transplant; chronic eosinophilic leukaemia; conditioning; hypereosinophilic syndrome; non-relapse mortality EN allogeneic stem cell transplant chronic eosinophilic leukaemia conditioning hypereosinophilic syndrome non-relapse mortality 209 213 5 06/27/22 20220701 NES 220701 Hypereosinophilic syndrome (HES) and chronic eosinophilic leukaemia (CEL), not otherwise specified (NOS) are rare haematological disorders.1 Allogeneic haematopoietic cell transplantation (allo-HCT) has been reported in single case reports or small case series only for both refractory HES or CEL, NOS and outcomes remain ill-defined.1-3 HES normally demonstrates a male predominance, likely underrecognized, with a variable clinical course. [Extracted from the article]

Summary: Strategies for relapse prevention after allogeneic transplantation in acute leukaemia are warranted. A registry‐based matched‐pair analysis evaluated the efficacy of prophylactic donor lymphocyte infusion (proDLI). Adults receiving proDLI in complete remission (CR) and controls were pair‐matched for age, diagnosis, cytogenetics, stage, donor, gender, conditioning and T‐cell depletion. Eighty‐nine pairs were identified (median follow‐up: 6.9 years). Within the entire cohort, no difference was observed. However, among patients with high‐risk acute myeloid leukaemia (AML) (unfavourable cytogenetics and/or transplanted beyond first CR), proDLI recipients had improved overall survival (69.8% vs. 40.2% in controls, P = 0.027). ProDLI has moderate efficacy, but can contribute to improved outcome in high‐risk AML. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Blood cultures (BCs) are essential in the evaluation of neutropenic fever. Modern BC systems have significantly reduced the time‐to‐positivity (TTP) of BC. This study explores the probability of bacteraemia when BCs have remained negative for different periods of time. Methods: All adult patients with neutropenia and bacteraemia were included (January 2012‐February 2016). Predictive clinical factors for short (≤16 hours) and long (>24 hours) TTP were determined. The residual probability of bacteraemia was estimated for the scenario of negative BC 24 hours after collection. Results: The cohort consisted of 154 patients, accounting for 190 episodes of bacteraemia. Median age of 61 years, 60.5% were male. In 123 (64.7%) episodes, BC yielded a single Gram‐positive micro‐organism and in 49 (25.8%) a Gram‐negative micro‐organism (median TTP 16.7, 14.5 hours respectively, P < .01). TTP was ≤24 hours in 91.6% of episodes. Central line‐associated bacteraemia was associated with long TTP. The probability of bacteraemia if BC had remained negative for 24 hours was 1%‐3%. Conclusions: The expected TTP offers guidance in the management of patients with neutropenia and suspected bacteraemia. The knowledge of negative BC can support a change in working diagnosis, and impact clinical decisions as soon as 24 hours after BC collection. [ABSTRACT FROM AUTHOR]

The article focuses on a study regarding the use of polymerase chain reaction (PCR) for rapid identification of full-length immunoglobulin rearrangements without primer binding bias. It mentions that B cells recognize specific antigens by their membrane-bound B-cell receptor (BCR). It also mentions that non-templated point mutations are introduced into BCR genes by somatic hypermutation (SHM).

Atypical chronic myeloid leukaemia ( aCML) is an aggressive malignancy for which allogeneic haematopoietic stem cell transplantation (allo- HSCT) represents the only curative option. We describe transplant outcomes in 42 patients reported to the European Society for Blood and Marrow Transplantation ( EBMT) registry who underwent allo- HSCT for aCML between 1997 and 2006. Median age was 46 years. Median time from diagnosis to transplant was 7 months. Disease status was first chronic phase in 69%. Donors were human leucocyte antigen ( HLA)-identical siblings in 64% and matched unrelated ( MUD) in 36%. A reduced intensity conditioning was employed in 24% of patients. T-cell depletion was applied in 87% and 26% of transplants from MUD and HLA-identical siblings, respectively. According to the EBMT risk-score, 45% of patients were 'low-risk', 31% 'intermediate-risk' and 24% 'high-risk'. Following allo- HSCT, 87% of patients achieved complete remission. At 5 years, relapse-free survival was 36% and non-relapse mortality ( NRM) was 24%, while relapse occurred in 40%. Patient age and the EBMT score had an impact on overall survival. Relapse-free survival was higher in MUD than in HLA-identical sibling HSCT, with no difference in NRM. In conclusion, this study confirmed that allo- HSCT represents a valid strategy to achieve cure in a reasonable proportion of patients with aCML, with young patients with low EBMT risk score being the best candidates. [ABSTRACT FROM AUTHOR]

The article focuses on immunoglobulin class switch recombination (CSR) of B-cell receptors (BCR) in follicular lymphoma (FL), particularly on the impact of class switching on a more aggressive FL. Topics discussed include procedure observed in BCR selection, prognostic significance of N-glycosylation sites found in most FL, and BCR as a stable immunobiological feature of FL.

Thiotepa is an alkylating compound with an antineoplastic and myeloablative activity and can mimic the effect of radiation. However, it is unknown whether this new regimen could safely replace the longestablished ones. This retrospective matched-pair analysis evaluated the outcome of adults with acute myeloid leukaemia in first complete remission who received myeloablative conditioning either with a thiotepa-based (n = 121) or a cyclophosphamide/total body irradiation-based (TBI; n = 358) regimen for allogeneic hematopoietic stem cell transplantation from an HLA-matched sibling or an unrelated donor. With a median follow-up of 44 months, the outcome was similar in both groups. Acute graft-versus-host disease grade II-IV was observed in 25% after thiotepa-containing regimen versus 35% after TBI (P = 0.06). The 2-yr cumulative incidence of chronic graft-versus-host disease was 40.5% for thiotepa and 41% for TBI (P = 0.98). At 2 yrs, the cumulative incidences of non-relapse mortality and relapse incidence were 23.9% (thiotepa) vs. 22.4% (TBI; P = 0.66) and 17.2% (thiotepa) vs. 23.3% (TBI; P = 0.77), respectively. The probabilities of leukaemia-free and overall survival at 2 yrs were not significantly different between the thiotepa and TBI groups, at 58.9% vs. 54.2% (P = 0.95) and 61.4% vs. 58% (P = 0.72), respectively. Myeloablative regimens using combinations including thiotepa can provide satisfactory outcomes, but the optimal conditioning remains unclear for the individual patient in this setting. [ABSTRACT FROM AUTHOR]

The status of umbilical cord blood transplantation ( UCBT) in adults with Philadelphia-positive acute lymphoblastic leukaemia (Ph+ ALL) and the impact of minimal residual disease ( MRD) before transplant are not well established. We analysed 98 patients receiving UCBT for Ph+ ALL in first ( CR1) or second ( CR2) complete remission ( CR1, n = 79; CR2, n = 19) with MRD available before UCBT (92% analysed by reverse transcription polymerase chain reaction). Median age was 38 years and median follow-up was 36 months; 63% of patients received myeloablative conditioning and 42% received double-unit UCBT. Eighty-three patients were treated with at least one tyrosine kinase inhibitor before UCBT. MRD was negative (−) in 39 and positive (+) in 59 patients. Three-year cumulative incidence of relapse was 34%; 45% in MRD+ and 16% in MRD− patients ( P =0·013). Three-year cumulative incidence of non-relapse mortality was 31%; it was increased in patients older than 35 years ( P = 0·02). Leukaemia-free survival ( LFS) at 3 years was 36%; 27% in MRD+ and 49% in MRD− patients ( P = 0·05), and 41% for CR1 and 14% for CR2 ( P = 0·008). Multivariate analysis identified only CR1 as being associated with improved LFS. In conclusion, MRD+ before UCBT is associated with increased relapse. Strategies to decrease relapse in UCBT recipients with Ph+ ALL and MRD+ are needed. [ABSTRACT FROM AUTHOR]

BACKGROUND: B-cell receptors (BCRs) and their recognition of specific epitopes may play a pivotal role in the development and progression of chronic lymphocytic leukemia (CLL). In this study, the authors set up a model system to explore epitope reactivity and its clinical relevance in CLL. METHODS: Epitope-mimicking peptides were selected from phage display libraries on 6 CLL BCRs from randomly chosen patients. The binding of the 6 index epitope mimics was evaluated in a set of 100 unrelated CLL samples. Epitope recognition patterns were correlated with the clinical course of the disease. RESULTS: Surprisingly, all CLL samples recognized 1 or several index epitopes, and some revealed marked polyreactivity. Patients with CLL who expressed BCRs that reacted with ≥5 epitope mimics had a significantly worse clinical course than less polyreactive patients (median time to first treatment, 24 months vs 102 months). This effect was independent of otherwise known prognostic markers. CONCLUSIONS: The authors introduced a system with which to model epitope reactivity of CLL BCRs without previous knowledge of potential antigens. The findings indicated that a polyreactive epitope recognition pattern may be a determinant of an aggressive clinical course in this disease. This further emphasizes the functional and prognostic relevance of BCR epitope recognition in CLL. [ABSTRACT FROM AUTHOR]

Summary Direct contact with stromal cells protects chronic lymphocytic leukaemia (CLL) B cells from chemotherapy-induced apoptosis in vitro. Blockade of CXCR4 signalling antagonizes stroma-mediated interactions and restores CLL chemosensitivity. In vivo, administration of CXCR4 antagonists effectively mobilizes haematopoietic progenitor cells. Therefore, combinations of CXCR4 blockade and cytoreductive treatment with selective activity on CLL cells may avoid potential haematotoxicity. Hence, we tested CXCR4 antagonists in the context of passive and active immunotherapeutic approaches. We evaluated how efficiently rituximab, alemtuzumab and cytotoxic T cells killed CLL cells cocultured with stromal cells in the presence and absence of a CXCR4 antagonist. Stromal cell contact attenuated rituximab- and alemtuzumab-induced complement-dependent cytotoxicity of CLL cells. Addition of CXCR4 antagonists abrogated the protective effect of stroma. In contrast, stromal cells did not impair antibody-dependent cell-mediated cytotoxicity and cytotoxicity induced by activated T cells. Destruction of microtubules in CLL target cells restored the protective effect of stroma coculture for CLL cells during Natural Killer cell attack by preventing mitochondrial relocalization towards the immunological synapse. Our data identify the combination of CXCR4 antagonists with passive - but not active - immunotherapy as a promising potential treatment concept in CLL. [ABSTRACT FROM AUTHOR]

The human chemokine receptor CRAM (chemokine receptor on activated macrophages), encoded by the gene CCRL2, is a new candidate for the atypical chemokine receptor family that includes the receptors DARC, D6 and chemocentryx chemokine receptor (CCX-CKR). CRAM is maturation-stage-dependently expressed on human B lymphocytes and its surface expression is up-regulated upon short-term CCL5 exposure. Here, we demonstrate that the homeostatic chemokine CCL19 is a specific ligand for CRAM. In radioactive labelling studies CCL19 bound to CRAM-expressing cells with an affinity similar to the described binding of its other receptor CCR7. In contrast to the known CCL19/CCR7 ligand/receptor pair, CRAM stimulation by CCL19 did not result in typical chemokine-receptor-dependent cellular activation like calcium mobilization or migration. Instead, we demonstrate that CRAM is constitutively recycling via clathrin-coated pits and able to internalize CCL19 as well as anti-CRAM antibodies. As this absence of classical chemokine receptor responses and the recycling and internalization features are characteristic for non-classical chemokine receptors, we suggest that CRAM is the newest member of this group. As CCL19 is known to be critically involved in lymphocyte and dendritic cell trafficking, CCL19-binding competition by CRAM might be involved in modulating these processes. [ABSTRACT FROM AUTHOR]

Objectives: Individual immunoglobulins expressed by B-cell lymphomas represent tumor-specific antigens (‘idiotypes’). Immunization with idiotype in follicular lymphoma patients may induce specific immune responses, sustained progression-free survival, and disappearance of minimal residual disease. Manufacturing of idiotype vaccines has mostly relied on heterohybridomas established from viable lymphoma cells. This paper describes the feasibility of production of GMP-grade idiotype vaccines as recombinant Fab fragments in Escherichia coli. Methods: IgH and IgL transcripts were analyzed by anchored PCR from 106 lymphoma and nine control biopsies. Lymphoma-derived V segments were inserted into prokaryotic expression plasmids. Recombinant idiotype Fab fragments were expressed in E. coli in a fermentation system. Results: Idiotype IgH and IgL transcripts were identified in 95% of 106 lymphoma biopsies according to stringent clonality criteria. Large-scale idiotype expression was successful in 69 of 78 cases (89%) and yielded a median of 17 mg (range: 1.2–250 mg) recombinant Fab protein. After affinity chromatography, median vaccine purity was 99% heterodimeric Fab protein (range: 72–100%). Bacterial protein contamination was detectable in one vaccine only. Fab proteins with IgL lambda chains had a tendency for inferior yield and lesser purity than κ-type Fabs. Among other structural idiotype features (isotype, V family usage, somatic hypermutation pattern, novel glycosylation sites, CDR III net charge), no consistent influences on Fab yield or purity were detected. Conclusions: Anchored PCR cloning and subsequent protein expression in E. coli provides a reliable technological basis for clinical idiotype vaccination trials. [ABSTRACT FROM AUTHOR]

Despite improvements in HLA typing, graft-versus-host disease (GVHD) continues to impair the results after volunteer unrelated donor bone marrow transplantation (VUD-BMT) in adult patients compared with matched sibling BMT. Here, the outcome after VUD-BMT using a specific regimen with high-dose anti-T-lymphocyte globulin (ATG) was analysed. Fifty-five adult patients, median age 34 years (range 17–55 years), with acute or chronic leukaemia or myelodysplastic syndrome (MDS) were transplanted in first complete remission (CR1)/first chronic phase (CP1) (early disease) (n = 21) or in advanced (CR2/CP2, no remission) disease (n = 34) from an unrelated marrow donor. GVHD prophylaxis consisted of ATG-S (Fresenius) 60–90 mg/kg b.w. prior to transplantation, in addition to cyclosporin A and short-course methotrexate. Graft failure did not occur and white blood cell count (WBC) > 1·0 × 109/l was reached at median day +16. The cumulative incidence of acute (a)GVHD grade II–IV was 15% [95% CI (8%, 28%)] and of chronic GVHD was 51% [95% CI (38%, 68%)]. The cumulative incidence of relapse within 1 year was 0% [95% CI (0%, 19%)] and 21% [95% CI (11%, 40%)] for patients with early and advanced disease respectively. With a median follow-up of 28 months (range 16–45 months), 2-year disease-free and overall survival for patients transplanted in CR1/CP1 was 81% and 81% [95% CI (64%, 98%)], respectively, and for patients with advanced disease was 33% [95% CI (17%, 50%)] and 40% [95% CI (23%, 57%)] respectively. Complete and persistent donor chimaerism was seen in 77·5% of 40 patients evaluated. All 14 chronic myeloid leukaemia (CML)-CP1 patients became bcr–abl negative within 250 d. High-dose ATG pretransplant results in a low incidence of severe aGVHD without compromising donor chimaerism or elimination of minimal residual disease. Our results are similar to data obtained after matched sibling donor transplantation. [ABSTRACT FROM AUTHOR]