Addition of Anti-thymocyte Globulin in Allogeneic Stem Cell Transplantation With Peripheral Stem Cells From Matched Unrelated Donors Improves Graft-Versus-Host Disease and Relapse Free Survival.

Anti-thymocyte globulin (ATG) is commonly used to prevent graft-versus-host disease (GvHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). To evaluate the impact of ATG as part of the GvHD prophylaxis in our institution, we report the outcome of 415 patients with matched unrelated donors (MUD) transplanted for hematological malignancies with or without ATG from 2005 to 2019 at Oslo University Hospital, Norway. The following groups were compared: (1) 154 patients transplanted with peripheral blood stem cells (PBSC) without ATG 2005-2014. (2) 137 patients transplanted with bone marrow stem cells (BMSC) 2005-2019. (3) 124 patients transplanted with PBSC and ATG (PBSC + ATG) 2014-2019. Three years survival was similar in the groups, 61% following allografting with PBSC, 54% with BMSC, and 59% with PBSC + ATG. Acute GvHD grade III-IV was 14%, 14%, and 7%; chronic GvHD was 81%, 32, and 26%; and extensive cGvHD 44%, 15%, and 6% in the corresponding groups. Both acute and chronic GvHD were significantly reduced in the PBSC + ATG-versus the PBSC group (p < 0.05 and p < 0.001 respectively).Transplant-related mortality (TRM) was 33%, 25%, and 17% (p = 0.18). Graft versus host disease and relapse free survival (GRFS) at 3 years was 43 %, 43%, and 64% in the groups. Adding ATG to the GvHD prophylaxis regimen of MUD allo-HSCT with PBSC resulted in a substantial reduction of both acute and chronic GvHD without compromising the disease control, reflected in a superior 3 years GRFS.

The CD34+ Cell Dose Matters in Hematopoietic Stem Cell Transplantation with Peripheral Blood Stem Cells from Sibling Donors.

The effect of CD34+ cell dose in allogeneic hematopoietic stem cell transplantation (HSCT) on overall survival (OS) and incidence of acute and chronic graft-versus-host disease (GvHD) has not been established and few studies have been performed. Our single center analysis included 189 patients with hematological malignancies who received peripheral blood stem cell (PBSC) grafts from sibling donors. Myeloablative conditioning was used in 88 cases and 101 received reduced intensity conditioning. The median CD34+ cell dose was 5.6 × 106/kg (0.6-17.0). In the multivariate analysis, a CD34 cell dose of 6-7 × 106/kg was associated with better OS and lower transplant-related mortality (TRM), while a dose of <5 × 106/kg led to increased relapse and reduced chronic GVHD (cGVHD). A high CD34 cell-dose (>6.5 × 106/kg) correlated with less acute GVHD (aGVHD) II-IV. We conclude that the CD34 cell dose has an impact on the outcome of HSCT from sibling donor PBSCs.

What is the outcome in patients with acute leukaemia who survive severe acute graft-versus-host disease?

BACKGROUND: Acute graft-versus-host disease (aGVHD) is a major complication of allogeneic haematopoietic stem cell transplantation (HSCT). With new promising therapies, survival may improve for severe aGVHD. OBJECTIVES: We wanted to analyze the long-term outcome in patients who survive severe aGVHD. METHODS: This study was a landmark analysis of 23 567 patients with acute Leukaemia who survived for more than 6 months after HSCT, 2002-2014. Patients alive after severe aGVHD (n = 1738) were compared to controls. RESULTS: Patients with severe aGVHD had higher non-relapse mortality (NRM) and higher rate of extensive chronic GVHD (cGVHD) than the controls (P < 10-5 ). The probability of relapse was significantly lower in the severe aGVHD group, but Leukaemia-free survival (LFS) and overall survival were significantly lower than for the controls (P < 10-5 ). Five-year LFS in patients with severe aGVHD was 49%, as opposed to 61% in controls with no or mild GVHD and 59% in patients with moderate GVHD. CONCLUSIONS: HSCT patients who survive severe aGVHD have higher risk of developing extensive cGVHD, a higher NRM, a lower relapse probability, and lower LFS than other HSCT patients. This study is a platform for outcome analysis in patients treated with novel therapies for acute GVHD.

Autologous bone marrow Th cells can support multiple myeloma cell proliferation in vitro and in xenografted mice.

Multiple myeloma (MM) is a plasma cell malignancy where MM cell growth is supported by the bone marrow (BM) microenvironment with poorly defined cellular and molecular mechanisms. MM cells express CD40, a receptor known to activate autocrine secretion of cytokines and elicit proliferation. Activated T helper (Th) cells express CD40 ligand (CD40L) and BM Th cells are significantly increased in MM patients. We hypothesized that activated BM Th cells could support MM cell growth. We here found that activated autologous BM Th cells supported MM cell growth in a contact- and CD40L-dependent manner in vitro. MM cells had retained the ability to activate Th cells that reciprocated and stimulated MM cell proliferation. Autologous BM Th cells supported MM cell growth in xenografted mice and were found in close contact with MM cells. MM cells secreted chemokines that attracted Th cells, secretion was augmented by CD40-stimulation. Within 14 days of culture of whole BM aspirates in autologous serum, MM cells and Th cells mutually stimulated each other, and MM cells required Th cells for further expansion in vitro and in mice. The results suggest that Th cells may support the expansion of MM cells in patients.

HOX gene expression predicts response to BCL-2 inhibition in acute myeloid leukemia.

Inhibitors of B-cell lymphoma-2 (BCL-2) such as venetoclax (ABT-199) and navitoclax (ABT-263) are clinically explored in several cancer types, including acute myeloid leukemia (AML), to selectively induce apoptosis in cancer cells. To identify robust biomarkers for BCL-2 inhibitor sensitivity, we evaluated the ex vivo sensitivity of fresh leukemic cells from 73 diagnosed and relapsed/refractory AML patients, and then comprehensively assessed whether the responses correlated to specific mutations or gene expression signatures. Compared with samples from healthy donor controls (nonsensitive) and chronic lymphocytic leukemia (CLL) patients (highly sensitive), AML samples exhibited variable responses to BCL-2 inhibition. Strongest CLL-like responses were observed in 15% of the AML patient samples, whereas 32% were resistant, and the remaining exhibited intermediate responses to venetoclax. BCL-2 inhibitor sensitivity was associated with genetic aberrations in chromatin modifiers, WT1 and IDH1/IDH2. A striking selective overexpression of specific HOXA and HOXB gene transcripts were detected in highly BCL-2 inhibitor sensitive samples. Ex vivo responses to venetoclax showed significant inverse correlation to ß2-microglobulin expression and to a lesser degree to BCL-XL and BAX expression. As new therapy options for AML are urgently needed, the specific HOX gene expression pattern can potentially be used as a biomarker to identify venetoclax-sensitive AML patients for clinical trials.

Benzylpenicillin plus an aminoglycoside versus meropenem in neutropenic lymphoma and leukaemia patients with a suspected bacterial infection: a randomized, controlled trial.

OBJECTIVES: In Norway, initial treatment of febrile neutropenia (FN) has traditionally been benzylpenicillin plus an aminoglycoside. Internationally, FN is often treated with a broad-spectrum ß-lactam antibiotic. We aimed to compare these two regimens in a prospective, randomized, trial in patients with lymphoma or leukaemia with an expected period of neutropenia ≥7 days, and a suspected bacterial infection. METHODS: Adult neutropenic patients with lymphoma or leukaemia, and a suspected bacterial infection, were randomized for treatment with benzylpenicillin plus an aminoglycoside or meropenem. The primary endpoint was clinical success, defined as no modification of antibiotics and clinical stability 72 h after randomization. RESULTS: Among 322 randomized patients, 297 proved evaluable for analyses. Fifty-nine per cent (95% CI 51%-66%), (87/148) of the patients given benzylpenicillin plus an aminoglycoside were clinically stable, and had no antibiotic modifications 72 h after randomization, compared with 82% (95% CI 75%-87%), (122/149) of the patients given meropenem (p <0.001). When the antibiotic therapy was stopped, 24% (95% CI 18%-32%), (36/148) of the patients given benzylpenicillin plus an aminoglycoside, compared with 52% (95% CI 44%-60%), (78/149) of the patients given meropenem, had no modifications of their regimens (p <0.001). In the benzylpenicillin plus an aminoglycoside arm, the all-cause fatality within 30 days of randomization was 3.4% (95% CI 1.2%-7.9%), (5/148) of the patients, compared with 0% (95% CI 0.0%-3.0%), (0/149) of the patients in the meropenem arm (p 0.03). CONCLUSION: Clinical success was more common in FN patients randomized to meropenem compared with the patients randomized to benzylpenicillin plus an aminoglycoside. The all-cause fatality was higher among the patients given benzylpenicillin plus an aminoglycoside.

Common variable immunodeficiency revisited: normal generation of naturally occurring dendritic cells that respond to Toll-like receptors 7 and 9.

Patients with common variable immunodeficiency (CVID) have reduced numbers and frequencies of dendritic cells (DCs) in blood, and there is also evidence for defective activation through Toll-like receptors (TLRs). Collectively, these observations may point to a primary defect in the generation of functional DCs. Here, we measured frequencies of plasmacytoid DCs (pDCs) and myeloid DCs (mDCs) in peripheral blood of 26 CVID patients and 16 healthy controls. The results show that the patients have reduced absolute counts of both subsets. However, the decreased numbers in peripheral blood were not reflected in reduced frequencies of CD34(+) pDC progenitors in the bone marrow. Moreover, studies at the single cell level showed that DCs from CVID patients and healthy controls produced similar amounts of interferon-α or interleukin-12 and expressed similar levels of activation markers in response to human cytomegalovirus and ligands for TLR-7 and TLR-9. The study represents the most thorough functional characterization to date, and the first to assess bone marrow progenitor output, of naturally occurring DCs in CVID. In conclusion, it seems unlikely that CVID is secondary to insufficient production of naturally occurring DCs or a defect in their signalling through TLR-7 or TLR-9.

Lung transplantation for bronchiolitis obliterans syndrome after allo-SCT.

Chronic GVHD (cGVHD) associated bronchiolitis obliterans syndrome (BOS) is a serious complication after allo-SCT, and lung transplantation (LTx) may be the ultimate treatment option. To evaluate this treatment, data on all patients with LTx after allo-SCT ever performed in Sweden, Norway, Denmark and Finland were recorded and compared with survival data from the Scandiatransplant registry. In total, LTx after allo-SCT had been performed in 13 patients. Allo-SCT was done because of AML (n=6), CML (n=3), ALL (n=2), immunodeficiency (n=1) and aplastic anemia (n=1). All developed clinical cGVHD, with median interval from allo-SCT to LTx of 8.2 (0.7-16) years. Median age at LTx was 34 (16-55) years, and the median postoperative observation time was 4.2 (0.1-15) years. Two patients died, one due to septicemia, the other of relapsing leukemia, after 2 and 14 months, respectively. Four developed BOS, one of these was retransplanted. The survival did not significantly differ from the survival in matched LTx controls, being 90% 1 year and 75% 5 years after LTx compared with 85% and 68% in the controls. We therefore suggest that LTx may be considered in carefully selected patients with BOS due to cGVHD after allo-SCT.

Relationship between clinical and BK virological response in patients with late hemorrhagic cystitis treated with cidofovir: a retrospective study from the European Group for Blood and Marrow Transplantation.

To investigate the relationship between clinical response and modification of BK viremia, we assessed retrospectively 32 cases of hemorrhagic cystitis (HC) after allogeneic hematopoietic SCT that were treated with i.v. cidofovir (CDV). They were 22 men (69%) and 10 women (31%) with a median age of 24 years, range 3-62. The median number of CDV doses was 3, range 1-8, and the treatment lasted for a median of 3 weeks, range 1-10. Clinical improvement of HC was observed in 27 patients (84%). In 12 of 32 episodes (37.5%), BK viremia was determined before every CDV administration and a complete clinical response was observed in 10 of 12 patients (83%), the reduction of BK viremia load being 1 log by 2 weeks after starting CDV. Nephrotoxicity related to CDV was observed in nine patients. Among 26 patients with 100-day follow-up, 4 of 4 patients who had a complete clinical response by 30 days were alive vs 16 of 22 (73%) who did not have the resolution of HC in this time frame. We conclude that in patients with HC, the response to CDV treatment is usually associated with a significant reduction of BK viremia load.

Ultra-short course sirolimus contributes to effective GVHD prophylaxis after reduced-intensity allogeneic hematopoietic cell transplantation.

Reduced-intensity conditioning (RIC) allo-SCT is a potentially curative treatment approach for patients with relapsed Hodgkin's or non-Hodgkin's lymphoma. In the present study, 37 patients underwent RIC allo-SCT after induction treatment with EPOCH-F(R) using a novel form of dual-agent immunosuppression for GVHD prophylaxis with CsA and sirolimus. With a median follow-up of 28 months among survivors, the probability for OS at 3 and 5 years was 56%. Treatment-related mortality was 16% at day +100 and 30% after 1 year of transplant. Acute GVHD grades II-IV developed in 38% of patients, suggesting that the regimen consisting of CsA and an ultra-short course of sirolimus is effective in the prevention of acute GVHD.

Evidence for the involvement of galectin-3 in mesenchymal stem cell suppression of allogeneic T-cell proliferation.

Human bone marrow-derived mesenchymal stem cells (MSC) are multipotent non-hematopoietic progenitors that have regulatory activity on immune cells. NOD- and Toll-like receptors (NLR, TLR) have several roles in immunity, including those relevant to pathogen recognition and shaping the course of immune responses by controlling gene expression. We have shown that these innate immune receptors are expressed by hematopoietic CD34+ progenitors and MSC. To uncover genes critical in MSC function, first we have used microarray to screen for potential transcripts whose levels are altered in response to NOD-1 and TLR-2 activation, and second we validated some candidate genes using real-time RT-PCR, Western blots and cellular assays. Amongst the altered genes, galectin-3 was upregulated at both mRNA and protein levels in response to TLR-2 activation. Interestingly, MSC secreted galectin-3, a protein known to modulate T-cell proliferation, gene expression, cell adhesion and migration. Knockdown of galectin-3 in MSC using small interfering RNA (siRNA) reduced the immunosuppressive effect of MSC on mixed lymphocyte cultures when compared to cells treated with an irrelevant siRNA (P < 0.05). Collectively, the data emphasize a new role of galectin-3 in the immunomodulatory function of MSC and indicate that NOD signalling pathway is also functional in these cells.

Homeostatic chemokines CCL19 and CCL21 promote inflammation in human immunodeficiency virus-infected patients with ongoing viral replication.

CCL19 and CCL21 and their receptor CCR7 are expressed constitutively within lymphoid organs, regulating lymphocyte homing. Recent studies suggest that these chemokines may have inflammatory properties. We hypothesized a role of CCL19/CCL21 in human immunodeficiency virus (HIV) infection by promoting inflammation. We examined the expression of CCL19 and CCL21 in mononuclear cells from peripheral blood mononuclear cells (PBMC) and bone marrow mononuclear cells (BMMC) in HIV-infected patients before and during highly active anti-retroviral therapy (HAART). We also examined the ability of CCL19/CCL21 to promote inflammatory responses in these patients. PBMC from untreated HIV-infected patients (n = 29) released enhanced levels of CCL19 spontaneously compared with cells from controls (n = 20), particularly in those with symptomatic disease (n = 15, P < 0.01 versus controls). During HAART (n = 9), there was a decrease in the spontaneous CCL19 release and an increase in the phytohaemagglutinin-stimulated CCL19 release in both PBMC (P < 0.01) and BMMC (P < 0.05). In patients with enhanced HIV replication there was an increased proportion of inflammatory CD8(+)CCR7(-)CD45RA(-) T cells in peripheral blood [P < 0.01 and P < 0.05 versus controls, untreated (n = 9) and treatment failure (n = 8), respectively]. In vitro, CCL19/CCL21 promoted an inflammatory response in PBMC when accompanied by high viral load, irrespective of HAART. The HIV-tat protein significantly boosted the inflammatory effect of CCL19/CCL21 in PBMC. These findings link a dysregulated CCL19/CCL21/CCR7 system in HIV-infected patients to persistent inflammation and HIV replication, not only in untreated HIV infection, but also in treatment failure during HAART.

High expression of CD7 on CD34+ cells is not linked to deletion of derivative chromosome 9 or lack of dendritic cells in chronic myeloid leukaemia.

OBJECTIVE: High expression of CD7 on CD34+ cells (>20 %) has been shown to be associated with inferior prognosis in chronic myeloid leukaemia (CML), but the reason has not been unravelled. We set out to investigate whether lack of dendritic cells or der(9)t(9;22)(q34;q11) deletions might be correlated with increased CD7 expression on CD34+ cells in CML. MATERIAL AND METHODS: We identified 43 patients in our cohort of CML patients in the first chronic phase in whom we were able to assess the expression of CD7 on CD34+ cells. der(9)t(9;22) deletions were evaluated by FISH (fluorescent in situ hybridization) analyses and the proportions of plasmacytoid and myeloid dendritic cells were assessed by flow cytometry. RESULTS: High and low expressions of CD7 on CD34+ cells were found in 19 and 24 patients, respectively. Two out of 20 patients examined had a der(9)t(9;22)(q34;11) deletion, one patient with high expression and one with low expression of CD7 on CD34+ cells. The proportions of plasmacytoid dendritic cells (PDCs) and myeloid dendritic cells (MDCs) were reduced in a majority of patients in our cohort, but no correlation was found between high or low expression of CD7 on CD34+ cells and the proportion of dendritic cells. CONCLUSIONS: A high proportion of CD34+CD7+ cells in patients with CML is not associated with der(9)t(9;22)(q34;q11) deletions. Nor did we find any correlation between CD7 expression on CD34+ cells and lack of dendritic cells. High expressions of CD7 on CD34+ cells and der(9)t(9;22)(q34;q11) deletions seem to be independent prognostic markers in CML.