Low production of reactive oxygen species in granulocytes is associated with organ damage in systemic lupus erythematosus

Introduction: Polymorphonuclear leukocytes (PMN) are main effector cells in the acute immune response. While the specific role of PMN in systemic lupus erythematosus (SLE) and autoimmunity is still unclear, their importance in chronic inflammation is gaining more attention. Here we investigate aspects of function, bone marrow release and activation of PMN in patients with SLE. Methods: The following PMN functions and subsets were evaluated using flow cytometry; (a) production of reactive oxygen species (ROS) after ex vivo stimulation with phorbol 12-myristate 13-acetate (PMA) or Escherichia coli (E. coli); (b) capacity to phagocytose antibody-coated necrotic cell material; (c) PMN recently released from bone marrow, defined as percentage of CD10(-)D16(low) in peripheral blood, and (d) PMN activation markers; CD11b, CD62L and C5aR. Results: SLE patients (n = 92) showed lower ROS production compared with healthy controls (n = 38) after activation ex vivo. The ROS production was not associated with corticosteroid dose or other immunotherapies. PMA induced ROS production was significantly reduced in patients with severe disease. In contrast, neither ROS levels after E. coli activation, nor the capacity to phagocytose were associated with disease severity. This suggests that decreased ROS production after PMA activation is a sign of changed PMN behaviour rather than generally impaired functions. The CD10(-)CD16(low) phenotype constitute 2% of PMN in peripheral blood of SLE patients compared with 6.4% in controls, indicating a decreased release of PMN from the bone marrow in SLE. A decreased expression of C5aR on PMN was observed in SLE patients, pointing towards in vivo activation. Conclusions: Our results indicate that PMN from SLE patients have altered function, are partly activated and are released abnormally from bone marrow. The association between low ROS formation in PMN and disease severity is consistent with findings in other autoimmune diseases and might be considered as a risk factor

ECP versus ruxolitinib in steroid-refractory acute GVHD – a retrospective study by the EBMT transplant complications working party

IntroductionExtracorporal Photophoresis (ECP) is in clinical use for steroid-refractory and steroid-dependent acute GVHD (SR-aGVHD). Based on recent Phase-III study results, ruxolitinib has become the new standard of care for SR-aGVHD. Our aim was to collect comparative data between ruxolitinib and ECP in SR-aGVHD in order to improve the evidence base for clinical decision making. MethodsWe asked EBMT centers if they were willing to participate in this study by completing a data form (Med-C) with detailed information on GVHD grading, -therapy, -dosing, -response and complications for each included patient.Results31 centers responded positively (14%) and we included all patients receiving alloSCT between 1/2017-7/2019 and treated with ECP or ruxolitinib for SR-aGVHD grades II-IV from these centers. We identified 53 and 40 patients with grades II-IV SR-aGVHD who were treated with ECP and ruxolitinib, respectively. We performed multivariate analyses adjusted on grading and type of SR-aGVHD (steroid dependent vs. refractory). At day+90 after initiation of treatment for SR-aGVHD we found no statistically significant differences in overall response. The odds ratio in the ruxolitinib group to achieve overall response vs. the ECP group was 1.13 (95% CI = [0.41; 3.22], p = 0.81). In line, we detected no statistically significant differences in overall survival, progression-free survival, non-relapse mortality and relapse incidence.DiscussionThe clinical significance is limited by the retrospective study design and the current data can’t replace prospective studies on ECP in SR-aGVHD. However, the present results contribute to the accumulating evidence on ECP as an effective treatment option in SR-aGVHD

Phagocyte Function Decreases after High-Dose Treatment with Melphalan and Autologous Stem Cell Transplantation in Patients with Multiple Myeloma.

High-dose melphalan with autologous hematopoietic stem cell transplantation (ASCT) is standard of care for younger newly diagnosed multiple myeloma patients, with the aim of achieving as deep and complete response as possible after various combinations of induction therapy. However, it is frequently associated with infectious complications. This study investigated the effects of high-dose treatment with autologous stem cell support on patients' innate immunity, with a focus on subpopulations and functioning of recently released polymorphonuclear leukocytes (PMNs) and monocytes in peripheral blood. Flow cytometry-based analysis was used to measure the degree of PMN maturation and activation, before and after ASCT and compared to healthy controls. After high-dose treatment and ASCT, a smaller proportion of patients' PMNs had capacity for oxidative burst. Moreover, patients' PMNs, both before and after ASCT, showed reduced capacity for phagocytosis. Eosinophils, which recently have been suggested to play a role in promoting malignant plasma cell proliferation, were markedly reduced after ASCT, with slow regeneration. HLA-DR expression by monocytes was significantly depressed after ASCT, a characteristic often attributed to monocytic myeloid-derived suppressor cells. Our results suggest that several aspects of phagocytic functions are impaired for at least 20 days after ASCT

Bone marrow eosinophils in plasma cell disorders

In experimental studies, eosinophils have been shown to promote the survival, proliferation, and retention of plasma cells in the bone marrow (BM). The clinical significance of eosinophils in plasma cell disorders (PCDs) in humans is largely unknown. This study focuses on the frequency and phenotype of eosinophils in the BM and peripheral blood (PB) in patients with untreated PCD compared with healthy controls. The number of eosinophils per se did not correlate with the number of BM plasma cells or disease stage. The expression of chemokine receptor 4, which is important in the homing capacity to bone marrow stromal cells, was significantly higher in patient eosinophils and increased with disease stage. BM eosinophils from patients, especially from those with manifest disease, were more activated. Another finding in this study was that eosinophils in PB and BM from both patients and healthy controls expressed CD80 (B7-1). We discuss probable immunomodulatory consequences of surface expression of CD80 by eosinophils in conditions with marked T-cell exhaustion (e.g., multiple myeloma). Finally, we found that patients treated with corticosteroids had low levels of circulating eosinophils but preserved levels of eosinophils in the BM

Bone Marrow Neutrophils of Multiple Myeloma Patients Exhibit Myeloid-Derived Suppressor Cell Activity

Activated normal density granulocytes (NDGs) can suppress T-cell responses in a similar way as myeloid-derived suppressor cells (MDSCs). In this study, we tested the hypothesis that NDGs from blood and bone marrow of multiple myeloma (MM) patients have the ability to suppress T-cells, as MDSC. MM is an incurable plasma cell malignancy of the bone marrow. Like most malignancies, myeloma cells alter its microenvironment to promote tumor growth, including inhibition of the immune system. We found that MM NDG from the bone marrow suppressed proliferation of T-cells, in contrast to healthy donors. The inhibitory effect could not be explained by changed levels of mature or immature NDG in the bone marrow. Moreover, NDG isolated from the blood of both myeloma patients and healthy individuals could inhibit T-cell proliferation and IFN-γ production. On the contrary to previous studies, blood NDGs did not have to be preactivated to mediate suppressive effects. Instead, they became activated during coculture, indicating that contact with activated T-cells is important for their ability to regulate T-cells. The inhibitory effect was dependent on the production of reactive oxygen species and could be reverted by the addition of its inhibitor, catalase. Our findings suggest that blood NDGs from MM patients are suppressive, but no more than NDGs from healthy donors. However, only bone marrow NDG from MM patients exhibited MDSC function. This MDSC-like suppression mediated by bone marrow NDG could be important for the growth of malignant plasma cells in MM patients

Organ sparing total marrow irradiation compared to total body irradiation prior to allogeneic stem cell transplantation

Objectives: Total body irradiation (TBI) is commonly used prior to hematopoietic stem cell transplantation (HSCT) in myeloablative conditioning regimens. However, TBI may be replaced by total marrow irradiation (TMI) at centres with access to Helical TomoTherapy, a modality that has the advantage of delivering intensity-modulated radiotherapy to long targets such as the entire bone marrow compartment. Toxicity after organ sparing TMI prior to HSCT has not previously been reported compared to TBI or with regard to engraftment data. Methods: We conducted a prospective observational study on 37 patients that received organ sparing TMI prior to HSCT and compared this cohort to retrospective data on 33 patients that received TBI prior to HSCT. Results: The 1-year graft-versus-host disease-free, relapse-free survival (GRFS) was 67.5% for all patients treated with TMI and 80.5% for patients with matched unrelated donor and treated with TMI, which was a significant difference from historical data on TBI patients with a hazard ratio of 0.45 (P =.03) and 0.24 (P <.01). Engraftment with a platelet count over 20 [K/µL] and 50 [K/µL] was significantly shorter for the TMI group, and neutrophil recovery was satisfactory in both treatment cohorts. There was generally a low occurrence of other treatment-related toxicities. Conclusions: Despite small cohorts, some significant differences were found; TMI as part of the myeloablative conditioning yields a high 1-year GRFS, fast and robust engraftment, and low occurrence of acute toxicity

A single-arm, open-label, phase 2 clinical trial evaluating disease response following treatment with BI-505, a human anti-intercellular adhesion molecule-1 monoclonal antibody, in patients with smoldering multiple myeloma.

BACKGROUND:Smoldering multiple myeloma (SMM) is an indolent disease stage, considered to represent the transition phase from the premalignant MGUS (Monoclonal Gammopathy of Undetermined Significance) state towards symptomatic multiple myeloma (MM). Even though this diagnosis provides an opportunity for early intervention, few treatment studies have been done and the current standard of care is observation until progression. BI-505, a monoclonal antibody directed against intercellular adhesion molecule 1 (ICAM-1) with promising anti-myeloma activity in preclinical trials, is a possible treatment approach for this patient category with potential to eliminate tumor cells with minimal long-term side effects. BI-505 was well tolerated in an earlier phase 1 trial. METHODS AND FINDINGS:In this phase 2 trial the effects of BI-505 in patients with SMM were studied. Four patients were enrolled and three of them completed the first cycle of treatment defined as 5 doses of BI-505, a total of 43 mg/kg BW, over a 7-week period. In the three evaluable patients, BI-505 showed a benign safety profile. None of the patients achieved a response as defined per protocol. EudraCT number: 2012-004884-29. CONCLUSIONS:The study was conducted to assess the efficacy, safety and pharmacodynamics of BI-505 in patients with SMM. BI-505 showed no clinically relevant efficacy on disease activity in these patients with SMM, even if well tolerated. TRIAL REGISTRATION:ClinicalTrials.gov Identifier: NCT01838369

Organ sparing total marrow irradiation compared to total body irradiation prior to allogeneic stem cell transplantation

Objectives: Total body irradiation (TBI) is commonly used prior to hematopoietic stem cell transplantation (HSCT) in myeloablative conditioning regimens. However, TBI may be replaced by total marrow irradiation (TMI) at centres with access to Helical TomoTherapy, a modality that has the advantage of delivering intensity-modulated radiotherapy to long targets such as the entire bone marrow compartment. Toxicity after organ sparing TMI prior to HSCT has not previously been reported compared to TBI or with regard to engraftment data. Methods: We conducted a prospective observational study on 37 patients that received organ sparing TMI prior to HSCT and compared this cohort to retrospective data on 33 patients that received TBI prior to HSCT. Results: The 1-year graft-versus-host disease-free, relapse-free survival (GRFS) was 67.5% for all patients treated with TMI and 80.5% for patients with matched unrelated donor and treated with TMI, which was a significant difference from historical data on TBI patients with a hazard ratio of 0.45 (P =.03) and 0.24 (P <.01). Engraftment with a platelet count over 20 [K/µL] and 50 [K/µL] was significantly shorter for the TMI group, and neutrophil recovery was satisfactory in both treatment cohorts. There was generally a low occurrence of other treatment-related toxicities. Conclusions: Despite small cohorts, some significant differences were found; TMI as part of the myeloablative conditioning yields a high 1-year GRFS, fast and robust engraftment, and low occurrence of acute toxicity

Impact of daratumumab-based induction on stem cell collection parameters in Swedish myeloma patients

Funding Agencies|ALF; Swedish Cancer foundation</p