Hyper-N-glycosylated SEL1L3 as auto-antigenic B-cell receptor target of primary vitreoretinal lymphomas

Primary vitreoretinal lymphoma (PVRL) is a rare subtype of DLBCL and can progress into primary central nervous system lymphoma (PCNSL). To investigate the role of chronic antigenic stimulation in PVRL, we cloned and expressed B-cell receptors (BCR) from PVRL patients and tested for binding against human auto-antigens. SEL1L3, a protein with multiple glycosylation sites, was identified as the BCR target in 3/20 PVRL cases. SEL1L3 induces proliferation and BCR pathway activation in aggressive lymphoma cell lines. Moreover, SEL1L3 conjugated to a toxin killed exclusively lymphoma cells with respective BCR-reactivity. Western Blot analysis indicates the occurrence of hyper-N-glycosylation of SEL1L3 at aa 527 in PVRL patients with SEL1L3-reactive BCRs. The BCR of a PVRL patient with serum antibodies against SEL1L3 was cloned from a vitreous body biopsy at diagnosis and of a systemic manifestation at relapse. VH4-04*07 was used in both lymphoma manifestations with highly conserved CDR3 regions. Both BCRs showed binding to SEL1L3, suggesting continued dependence of lymphoma cells on antigen stimulation. These results indicate an important role of antigenic stimulation by post-translationally modified auto-antigens in the genesis of PVRL. They also provide the basis for a new treatment approach targeting unique lymphoma BCRs with ultimate specificity.

The addition of rituximab to chemotherapy improves overall survival in mantle cell lymphoma-a pooled trials analysis

Mantle cell lymphoma (MCL) is a distinct subtype of B-cell lymphoma and commonly used induction immunochemotherapies include the anti-CD20 antibody rituximab. However, efficacy data for rituximab regarding overall survival (OS) in first line MCL therapy remain conflicting.We report long-term outcomes of a pooled trials analysis comparing Cyclophosphamide, Doxorubicine, Vincristine, Prednisone (CHOP) to R-CHOP in MCL to confirm efficacy on failure free survival (FFS) and OS in relevant subgroups. Untreated, adult MCL patients of two prospective trials assigned to CHOP or R-CHOP were included. Primary endpoints were FFS and OS, secondary endpoints included duration of response (DOR), secondary malignancies and OS after relapse. Between 1996 and 2003, 385 MCL patients were assigned to CHOP (201) or R-CHOP (184). After a median follow-up of 13.4 years, the addition of Rituximab significantly improved FFS (1.36 vs. 2.07 years, HR 0.62 (0.50-0.77)), OS (4.84 vs. 5.81 years, HR 0.78 (0.61-0.99)) and DOR (1.48 vs. 2.08 years, HR 0.67 (0.53-0.86)). Furthermore, Rituximab improved survival across different MCL risk groups. In a post-hoc analysis of OS after relapse comparing patients receiving chemotherapy with / without rituximab, rituximab maintained efficacy with a median OS of 3.10 vs. 2.11 years (HR 0.70, 0.54-0.91). The rate of secondary malignancies was 0.5 and 3.9% for hematological and 7 and 8% for non-hematological malignancies for CHOP and R-CHOP patients, respectively. We present mature results of a pooled MCL cohort, demonstrating prolonged FFS, OS and DOR for the combined immuno-chemotherapy, confirming the standard of care in first line treatment.

Vitamin D Enhances Immune Effector Pathways of NK Cells Thus Providing a Mechanistic Explanation for the Increased Effectiveness of Therapeutic Monoclonal Antibodies

Patients with diffuse large cell lymphoma who have an adequate vitamin D supply derive significantly more benefit from immuno-chemotherapy with rituximab than patients with vitamin D deficiency; this is especially true for female patients. We have already been able to show that vitamin D increases the antibody-dependent cytotoxicity (ADCC) of NK cells in a sex-dependent manner, but it is unclear how vitamin D makes NK cells more efficient.

METHODS

Healthy individuals with vitamin D deficiency were supplemented with vitamin D to sufficient levels. NK cells were isolated from blood samples before and after vitamin D saturation. For transcriptome analysis, we used the Affymetrix Gene-Chip 2.0™. Gene expression analysis as well as supervised and unsupervised pathway analysis were performed.

RESULTS

Among others the "NK cell-associated cytotoxicity pathway" increased after vitamin D substitution. Five IFN-α subtypes (2, 4, 6, 7 and 10) and IFN-κ were more highly expressed and are mainly responsible in these pathways. In contrast, the pathway "interferon-gamma response", as well as other sets in cytokine production and chemotaxis showed a reduction. Toll-like receptor genes (TLR-8, TLR-7, TLR-2) were downregulated and, therefore, are responsible for the decline of these pathways. The same could be shown for the "ubiquitin-ligase" pathway.

CONCLUSIONS

Increased expression of several IFN-α subtypes may explain the increased ADCC of NK cells in vitamin D-replenished and otherwise healthy subjects. Other regulators of interferon production and ADCC are compensatory upregulated in compensation, such as Toll-like receptors and those of the ubiquitin ligase, and normalize after vitamin D substitution.

Daratumumab for a Patient With Refractory Antineutrophil Cytoplasmatic Antibody-Associated Vasculitis

This case reports on a patient with antineutrophil cytoplasmatic antibody–associated vasculitis and severe pulmonary and cutaneous involvement who received conventional therapy that failed and who was rescued by daratumumab therapy.

Ars2-containing bispecific, Fab- and IgG1-format BAR-bodies to target DLBCL cells

Despite recent advances in the therapy of diffuse large B-cell lymphoma, not otherwise specified (DLBCL), around 30% of patients develop refractory disease or relapse after first-line treatment. Recently, Ars2 was reported as the auto-antigenic target of the B-cell receptor (BCR) in approximately 25% of activated B-cell DLBCL cases. Ars2 could be used to specifically target B cells expressing Ars2-reactive BCRs. However, the optimal therapeutic format to integrate Ars2 into has yet to be determined. To mimic therapeutic antibody formats, Ars2-containing bispecific and IgG1-like constructs (BCR antigens for reverse [BAR]-bodies) were developed. Two bispecific BAR-bodies connecting single-chain antibodies against CD16 or CD3 to the BCR-binding epitope of Ars2 were constructed. Both constructs showed strong binding to U2932 cells and induced effector cell-dependent and selective cytotoxicity against U2932 cells of up to 44% at concentrations of 20 μg/ml. Additionally, IgG1-format Ars2 BAR-bodies were constructed by replacing the variable heavy- and light-chain regions of a full-length antibody with the Ars2 epitope. IgG1-format Ars2 BAR-bodies also bound selectively to U2932 and OCI-Ly3 cells and induced selective cytotoxicity of up to 60% at 10 μg/ml. In conclusion, Ars2-containing bispecific and IgG1-format BAR-bodies both are new therapeutic formats to target DLBCL cells.

Adaptive humoral immune response and cellular immune status in cancer patients and patients under immunosuppression vaccinated against SARS-CoV-2

BACKGROUND

Patients with cancer and autoimmune diseases are at higher risk of severe COVID-19. They may not develop protective immune responses following vaccination. We investigated patients' cellular and humoral immune response after two COVID-19 vaccine doses.

RESEARCH DESIGN AND METHODS

Subjects were stratified into subgroups according to therapy and grade of immunosuppression at time of vaccination.

RESULTS

Antibody titers were compared to healthy controls. 32/122 (26%) did not develop detectable antibody titers. Of these, 22 (66.6%) had active therapy. Patients showed significant lower antibody titers compared to controls (median 790 vs. 3923 AU/mL, p = 0.026). Patients with active therapy had significant lower antibody titers compared to those without (median 302 vs. 3952 U/L P < 0.001). B-cell count was lower in the group without antibody titers (median 29.97 vs. 152.8; p = 0.002). 100% of patients under anti-CD20 therapy had no detectable antibody titer, followed by anti-TNF (66%), BTK inhibitors (50%), ruxolitinib (35.5%), TKI (14.2%), and lenalidomide (12.5%). Anti-CD20 therapy, ruxolitinib, BTK inhibitors, and anti-CD38 therapy presented significant lower antibody titers compared to controls.

CONCLUSIONS

Patients undergoing therapy for cancer or autoimmune diseases are at higher risk of insufficient humoral immune response following COVID-19 vaccination. Furthermore, alterations in the B-cell compartment correlate with lower antibody titers.

Cost-effectiveness of precision cancer medicine-current challenges in the use of next generation sequencing for comprehensive tumour genomic profiling and the role of clinical utility frameworks (Review)

Precision cancer medicine (PCM) is an emerging paradigm in oncology, which includes tumour comprehensive genomic profiling (CGP) to enable molecularly guided therapy. However, cost-effectiveness analyses of PCM are faced with several challenges and, thus, its cost-effectiveness remains unclear. Early trials using only molecularly guided therapy were faced with the challenge of providing adequate measures of outcome, which probably explains the modest treatment benefits demonstrated. Endpoints like the progression-free survival (PFS)2/PFS1 ratio may assist in overcoming this issue. Moreover, specific tumour subtypes appear to benefit more from PCM. Costs associated with next-generation sequencing (NGS) for CGP are decreasing, but targeted therapy itself represents a major cost driver. CGP not only enables prediction of response to treatment, but also resistance, and could thus prevent administration of unnecessary (and costly) therapies. In clinical practice, the presence of clinical frameworks, such as the Recommendations for the Use of NGS for Patients with Metastatic Cancers from the ESMO Precision Medicine Working Group, and the ESMO Scale for Clinical Actionability of Molecular Targets, are essential in appropriately identifying situations where PCM is clinically meaningful, thereby improving its cost-effectiveness.

Advances in Lymphoma Molecular Diagnostics

Lymphomas encompass a diverse group of malignant lymphoid neoplasms. Over recent years much scientific effort has been undertaken to identify and understand molecular changes in lymphomas, resulting in a wide range of genetic alterations that have been reported across all types of lymphomas. As many of these changes are now incorporated into the World Health Organization’s defined criteria for the diagnostic evaluation of patients with lymphoid neoplasms, their accurate identification is crucial. Even if many alterations are not routinely evaluated in daily clinical practice, they may still have implications in risk stratification, treatment, prognosis or disease monitoring. Moreover, some alterations can be used for targeted treatment. Therefore, these advances in lymphoma molecular diagnostics in some cases have led to changes in treatment algorithms. Here, we give an overview of and discuss advances in molecular techniques in current clinical practice, as well as highlight some of them in a clinical context.

Significant reduced loss of bone mineral density after four vs. six cycles of R-CHOP: an analysis of the FLYER-trial

Patients with diffuse large B-cell lymphoma (DLBCL) treated with the R-CHOP regime receive a high cumulative dose of prednisone. We used computer tomography-ascertained Hounsfield units (HU) as a surrogate parameter for bone mineral density (BMD) in three different locations of the L3 vertebral body at baseline and post-treatment. HU were measured in 50 patients with DLBCL of the previously published FLYER-trial which compared four cycles of R-CHOP + 2 × rituximab infusion to six cycles of R-CHOP in young, favorable DLBCL patients. In total, median loss was 26.8 HU in all patients over time. The median HU loss was significantly lower in the four cycles arm (21.3 HU vs. 41.3 HU, p = 0.023). In conclusion, young patients with DLBCL receiving R-CHOP have significant HU/BMD loss under treatment with R-CHOP. Patients receiving four cycles of R-CHOP had less HU/BMD loss than patients receiving six cycles.

Increased B-cell activity with consumption of activated monocytes in severe COVID-19 patients

The pathogenesis of autoimmune complications triggered by SARS-CoV2 has not been completely elucidated. Here, we performed an analysis of the cellular immune status, cell ratios, and monocyte populations of patients with COVID-19 treated in the intensive care unit (ICU) (cohort 1, N = 23) and normal care unit (NCU) (cohort 2, n = 10) compared with control groups: patients treated in ICU for noninfectious reasons (cohort 3, n = 30) and patients treated in NCU for infections other than COVID-19 (cohort 4, n = 21). Patients in cohort 1 presented significant differences in comparison with the other cohorts, including reduced frequencies of lymphocytes, reduced CD8+T-cell count, reduced percentage of activated and intermediate monocytes and an increased B/T8 cell ratio. Over time, patients in cohort 1 who died presented with lower counts of B, T, CD4+ T, CD8+ T-lymphocytes, NK cells, and activated monocytes. The B/T8 ratio was significantly lower in the group of survivors. In cohort 1, significantly higher levels of IgG1 and IgG3 were found, whereas cohort 3 presented higher levels of IgG3 compared to controls. Among many immune changes, an elevated B/T8-cell ratio and a reduced rate of activated monocytes were mainly observed in patients with severe COVID-19. Both parameters were associated with death in cohort 1.

Characterization of an HLA-restricted and human cytomegalovirus-specific antibody repertoire with therapeutic potential

With an infection rate of 60-90%, the human cytomegalovirus (HCMV) is very common among adults but normally causes no symptoms. When T cell-mediated immunity is compromised, HCMV reactivation can lead to increased morbidity and mortality. HCMV antigens are processed and presented as peptides on the cell surface via HLA I complexes to the T cell receptor (TCR) of T cells. The generation of antibodies against HCMV peptides presented on HLA complexes (TCR-like antibodies) has been described, but is without therapeutic applications to date due to the polygenic and polymorphic nature of HLA genes. We set out to obtain antibodies specific for HLA/HCMV-peptides, covering the majority of HLA alleles present in European populations. Using phage display technology, we selected 10 Fabs, able to bind to HCMV-peptides presented in the 6 different HLA class I alleles A*0101, A*0201, A*2402, B*0702, B*0801 and B*3501. We demonstrate specific binding of all selected Fabs to HLA-typed lymphoblastoid cell lines (EBV-transformed B cells) and lymphocytes loaded with HCMV-peptides. After infection with HCMV, 4/10 tetramerized Fabs restricted to the alleles HLA-A*0101, HLA-A*0201 and HLA-B*0702 showed binding to infected primary fibroblasts. When linked to the pseudomonas exotoxin A, these Fab antibodies induce highly specific cytotoxicity in HLA matched cell lines loaded with HCMV peptides. TCR-like antibody repertoires therefore represent a promising new treatment modality for viral infections and may also have applications in the treatment of cancers.

Progranulin-autoantibodies in sera of rheumatoid arthritis patients negative for rheumatoid factor and anti-citrullinated peptide antibodies

OBJECTIVES

Previously we discovered antibodies against progranulin (PGRN-abs) in a protein array-based screening of sera from various rheumatic diseases. Here we conducted a study to evaluate the prevalence of PGRN-abs in seropositive and seronegative rheumatoid arthritis (RA).

METHODS

PGRN-abs were determined in the sera from 257 RA patients being seropositive for RF-IgM and/or ACPA-IgG and from 224 seronegative RA patients who were prospectively included in this study (total RA cohort n=481). All serum samples from the included participants were tested for RF-IgM as well as for ACPA-IgG, and PGRN-abs were determined using a previously described ELISA. Statistics was performed using the χ2 test for evaluating differences in clinical data; to evaluate independent statistical effects on the frequency of PGRN-abs status a logistic regression model with Wald-test was performed.

RESULTS

PGRN-abs were detected in 25.3% from seropositive RA and in 21.0% from RF- and ACPA-negative RA resulting in a prevalence of 23.7% for both cohorts together. Comparing mean DAS28 values in the PGRN-abs positive cohort with the PGRN-abs negative cohort, the DAS28 value was significantly higher in PGRN-abs positive RA patients (3.81 vs. 3.50, p=0.038). A trend for higher frequencies of PGRN-abs in sera of RA patients with unfavourable characteristics such as erosive disease or requiring TNFi medication was observed.

CONCLUSIONS

These data suggest that the determination of PGRN-abs in seronegative RA patients may reduce their seronegative status. Further studies are required to evaluate PGRN-abs as a potential diagnostic marker in RA.

Allogeneic hematopoietic stem cell transplantation for patients with relapsed/refractory systemic anaplastic large cell lymphoma. A retrospective analysis of the Lymphoma Working Party of the European Society for Blood and Marrow Transplantation

Information regarding the curative role of allogeneic stem cell transplantation (allo-HCT) in systemic anaplastic large cell lymphoma (sALCL) is scarce. We analyzed the results of allo-HCT in patients with relapsed/refractory sALCL with special emphasis on the role of brentuximab vedotin (BV) as a bridge to allo-HCT. Forty-four patients (24 females, median age 38 years) with sALCL were included. Twenty-three patients (52%) received BV before allo-HCT; BV-treated patients were more heavily pretreated (≥3 lines of therapy in 74% vs. 38%, p = 0.04). Twenty-three patients (52%) were in complete remission (CR) at allo-HCT. Three-year nonrelapse mortality and incidence of relapse (IR) after allo-HCT were 7% and 40%, respectively. With a median follow-up of 39 (12-69) months for survivors, 3-year progression-free survival (PFS) and overall survival were 53% and 74%, respectively. Univariate analysis showed that heavily pretreated patients and those not in CR had a higher IR and a lower PFS. The use of BV before transplant did not impact on any of the outcomes. Allo-HCT is a curative therapeutic strategy in a significant proportion of patients with relapsed/refractory sALCL; BV does not seem to modify transplant-related outcomes but might be able to render more patients candidates for this curative treatment.

Determination of optimum vitamin D3 levels for NK cell-mediated rituximab- and obinutuzumab-dependent cellular cytotoxicity

Vitamin D3 (25-OH-D3) deficiency impairs rituximab-dependent cellular cytotoxicity and the outcome of patients with diffuse large B-cell and follicular lymphomas (DLBCL). Since the optimum 25-OH-D3 serum levels for NK cell-mediated antibody-dependent cellular cytotoxicity (ADCC) are unknown, we determined the 25-OH-D3 serum levels associated with maximum NK cell-mediated ADCC. CD20 antibody-loaded CD20+ B-cell lymphoma cell lines were cultured with NK cells and ADCC activity was determined by lactate dehydrogenase release assays. Using a newly developed formula, pre-defined 25-OH-D3 serum levels were achieved with high individual precision over a wide range. NK cells from 20 healthy individuals killed antibody-treated CD20+ lymphoma cells in a concentration- and E:T ratio-dependent manner with obinutuzumab displaying a stronger ADCC activity than rituximab. Maximum NK-cell activity and ADCC were observed at 65 ng/ml 25-OH-D3, the middle of the normal range (30-100 ng/ml). 25-OH-D3 serum levels around this range should be the target in interventional trials aiming at improving NK cell-mediated ADCC by 25-OH-D3 substitution. Lower levels do not provide significant ADCC improvements in individuals with 25-OH-D3 deficiency or insufficiency and might result in the failure of interventions with 25-OH-D3.

Safety and feasibility of electrical muscle stimulation in patients undergoing autologous and allogeneic stem cell transplantation or intensive chemotherapy

Intensive chemotherapy, with or without following autologous or allogeneic stem cell transplantation (HSCT), is often the only curative treatment option for patients with hematological malignancies and leave many survivors physically and psychologically impaired. Electrical muscle stimulation (EMS) is a proven tool to improve physical performance in seniors and patients with chronic diseases. We therefore investigated the safety and feasibility of EMS in 45 patients undergoing autologous HSCT (n = 13), allogeneic HSCT (n = 11) and intensive chemotherapy (n = 21). Furthermore, physical (assessed by 6-min walking distance (6MWD) and short physical performance battery (SPPB)) and psychological performance (assessed by multidimensional fatigue inventory (MFI) and the EORTC QOL-C30 questionnaire) were measured before chemotherapy (T1) and at discharge from hospital (T2). Four patients died due to septic shock, two withdrew consent before the start of EMS training and five stopped EMS training during the study because of chemotherapy-related complications, loss of motivation or loss of ability to use EMS autonomously. Thirty-four out of 45 (76%) patients used EMS throughout the study period and participated in physical and psychological tests at time points 1 and 2. EMS-related adverse events were hematoma (n = 1) and muscle pain (n = 2). No bleeding events > 1 according to the WHO bleeding scale occurred. Decline in 6MWD from T1 to T2 was 24 m. The SPPB score stayed the same with 11 points at T1 and T2. Most MFI subscales showed stable fatigue levels and quality of life (QoL) did not decrease significantly throughout therapy. EMS is feasible and safe in patients undergoing intensive chemotherapy. Trial registration: NCT03467087.

Association of 25-OH vitamin D deficiency with worse outcome for elderly patients with aggressive B-cell lymphomas treated with CHOP plus rituximab (R): An analysis of the RICOVER-60 trial of the German High-Grade Non-Hodgkin Lymphoma Study Group (DSHNHL)

8569

Background: Vitamin D deficiency was shown to be is associated with a worse outcome in patients with non-Hodgkin's lymphoma (Drake et al., 2010) To study whether this observation could be confirmed in patients with aggressive B-cell lymphomas treated uniformly within a prospective trial, we analyzed 25-OH vitamin D serum levels in patients treated within the RICOVER-60 trial of the DSHNHL. Methods: 25-OH Vitamin D serum levels were determined with a commercial chemoluminescence immunoassay in the serum from elderly patients of the RICOVER-60 trial which compared 6 or 8 cycles of CHOP, both with and without rituximab. Results: 193 of 359 pts (53.8%) had vitamin D deficiency (<10 ng/ml) and 165/359 patients (46.0%) had vitamin D insufficiency (10-30 ng/ml) according to current definitions. When treated with R-CHOP, patients with vitamin D levels ≤8 ng/ml had a 3-year EFS of 59% compared to 79% of patients with vitamin D serum levels >8 ng/ml; the respective figures for 3-year overall survival were 70% and 82%, respectively. In R-CHOP pts these differences were significant in a multivariable analysis adjusting for IPI risk factors with a hazard ratio (HR) of 2.1 (p=0.008) for EFS and a HR of 1.9 (p=0.040) for OS. In pts treated without R effects of vitamin D deficiency were significant only for OS (HR 1.8; p=0.025), but not with respect to EFS (HR 1.2; p=0.388). These results were confirmed in an independent validation set of 63 patients treated within the prospective RICOVER-noRx study. Conclusions: Vitamin D deficiency is a significant risk factor for patients with aggressive B-cell lymphomas treated with R-CHOP. The stronger adverse effect of vitamin D deficiency in patients receiving rituximab suggests that vitamin D deficiency interferes with the R mechanisms of this antibody. A prospective study evaluating the effects of vitamin D substitution on outcome of patients receiving R-CHOP is warranted. Supported by Deutsche Krebshilfe.

[Typical laboratory constellation of a non-ST-segment elevation myocardial infarction in polymyositis]

HISTORY AND ADMISSION FINDINGS

a 80-year-old women was admitted with a hypertensive crisis. Laboratory tests showed elevated cardiac enzymes (CK, CK-MB and troponin T). She was treated for suspected non-ST segment elevation myocardial infarction.

INVESTIGATIONS

a cardiovascular examination, which included echocardiography, coronary angiography and magnetic resonance imaging, excluded a cardiac cause of the laboratory reults. After complete assessment the patient was found to have long-standing polymyosits positive for Mi-2 antibodies. This had caused troponin T elevation from the release of regenerating muscles after chronic inflammatory damage. Troponin I, however, is truly cardiomyocyte specific and distinguishes between cardiac and non cardiac origin of CK, CK-MB and troponin T.

TREATMENT AND COURSE

prednisone medication was started with a single dose of 50mg, then gradually reduced. Follow-up examination merely revealed minimally active polymyositis.

CONCLUSION

troponin I should be measured in patients with inflammatory myositis/myopathies in order to diagnose and assess cardiac involvement.