Extracardiac 18F-florbetapir imaging in patients with systemic amyloidosis: more than hearts and minds

PURPOSE: 18F-Florbetapir has been reported to show cardiac uptake in patients with systemic light-chain amyloidosis (AL). This study systematically assessed uptake of 18F-florbetapir in patients with proven systemic amyloidosis at sites outside the heart. METHODS: Seventeen patients with proven cardiac amyloidosis underwent 18F-florbetapir PET/CT imaging, 15 with AL and 2 with transthyretin amyloidosis (ATTR). Three patients had repeat scans. All patients had protocolized assessment at the UK National Amyloidosis Centre including imaging with 123I-serum amyloid P component (SAP). 18F-Florbetapir images were assessed for areas of increased tracer accumulation and time-uptake curves in terms of standardized uptake values (SUVmean) were produced. RESULTS: All 17 patients showed 18F-florbetapir uptake at one or more extracardiac sites. Uptake was seen in the spleen in 6 patients (35%; 6 of 9, 67%, with splenic involvement on 123I-SAP scintigraphy), in the fat in 11 (65%), in the tongue in 8 (47%), in the parotids in 8 (47%), in the masticatory muscles in 7 (41%), in the lungs in 3 (18%), and in the kidney in 2 (12%) on the late half-body images. The 18F-florbetapir spleen retention index (SRI) was calculated. SRI >0.045 had 100% sensitivity/sensitivity (in relation to 123I-SAP splenic uptake, the current standard) in detecting splenic amyloid on dynamic imaging and a sensitivity of 66.7% and a specificity of 100% on the late half-body images. Intense lung uptake was seen in three patients, one of whom had lung interstitial infiltration suggestive of amyloid deposition on previous high-resolution CT. Repeat imaging showed a stable appearance in all three patients suggesting no early impact of treatment response. CONCLUSION: 18F-Florbetapir PET/CT is a promising tool for the detection of extracardiac sites of amyloid deposition. The combination of uptake in the heart and uptake in the spleen on 18F-florbetapir PET/CT, a hallmark of AL, suggests that this tracer holds promise as a screening tool for AL

Autologous stem cell transplantation vs bortezomib based chemotheraphy for the first‐line treatment of systemic light chain amyloidosis in the UK

OBJECTIVES: The benefit of autologous stem cell transplantation (ASCT) in the treatment of light chain (AL) amyloidosis requires re-evaluation in the modern era. This retrospective case-matched study compares ASCT to bortezomib for the treatment of patients with AL amyloidosis. METHODS: Newly diagnosed patients with AL amyloidosis treated with ASCT or bortezomib between 2001-2018 were identified. Patients were excluded if the time from diagnosis to treatment exceeded 12 months. Patients were matched on a 1:1 basis, using a propensity matched scoring approach. RESULTS: A total of 136 propensity-score matched patients were included (ASCT n= 68, bortezomib n=68). There was no significant difference in overall survival at two years (p=0.908, HR: 0.95, CI:0.41-2.20). For ASCT vs. bortezomib: overall haematological response rate at six months was 90.6% vs. 92.5%; organ response at 12 months: cardiac (70.0% vs. 54%, p>0.999), renal (74% vs.24%, p=0.463)) liver (21% vs. 22%, p=0.048); median progression free survival (50 vs. 42 months p=0.058, HR:0.61, CI:0.37-1.02) and time to next treatment (68 vs. 45 months, p=0.145, HR:0.61, CI:0.31-1.19). More patients required treatment in the bortezomib group compared to ASCT group at 24 months (41 vs. 23, Chi squared p=0.004) and 48 months (57 vs 41, Chi squared p= 0.004). CONCLUSIONS: This small retrospective study suggests that there is no clear survival advantage of ASCT over bortezomib therapy. A prospective randomised controlled trial evaluating ASCT in AL amyloidosis is critically needed

Administration of BPX-501 Cells Following Αβ T and B-Cell-Depleted HLA Haploidentical HSCT (haplo-HSCT) in Children with Acute Leukemias (AL)

Background Allogeneic HSCT is a well-established treatment for children with AL. For pts lacking a compatible matched related or unrelated donor, HLA-haplo-HSCT represents an alternative. Promising results were reported with selective depletion of αβ T and B cells (Locatelli, Blood 2017). PX-501 is an allogeneic product consisting of T cells modified to express the inducible caspase-9 (iC9) safety switch and truncated CD19 to allow monitoring and expansion of BPX-501 following transplant. BPX-501 provides broad virus and tumor-specific immunity; the safety switch provides the unique ability to promptly and durably resolve graft-versus-host disease (GvHD) symptoms following the administration of rimiducid. Aims Evaluate the safety and efficacy of BPX-501 in pediatric pts with AL by determining whether BPX-501 infusion can increase efficacy outcomes through an enhanced graft-versus-leukemic (GvL) effect, while maintaining a low risk of GvHD. Methods A subset of pts had high-risk ALs. BPX-501 was planned to be infused on day14±4 after the allograft with no post-transplant GvHD prophylaxis allowed. Pts who developed steroid-resistant GvHD could receive ≥1 dose of rimiducid. Results As of June 30, 2018, 100 pts with AL (described in Table 1) were efficacy evaluable. Median time for neutrophil and platelet engraftment was 16 and 12 days, respectively. Four pts (4.1%) experienced primary graft failure. Of 96 evaluable pts, 5 (3.1%) developed Grade III-IV aGvHD. Of 82 evaluable pts, 12 developed cGvHD (18.1%), with 3 moderate-severe. Rimiducid was administered to 10 pts. Best overall clinical response (CR/PR) post-rimiducid was 80% (8 pts). Among responding patients, 7 (87.5%) had a CR. Six (6.6%) pts died after transplantation. Efficacy outcomes in AL subsets are in Table 2. CD3+ and CD3+CD4+ T cells above 500 cells/ml were achieved by 180 and 270 days, respectively. IgA and IgM levels achieved normal values by 180 days. Conclusion BPX-501 following αβ-T and B-cell depleted haplo-HSCT represents a highly effective transplantation strategy for pediatric pts with AL. Rimiducid was an effective treatment for pts with steroid-resistant GvHD

99mTc-DPD scintigraphy in immunoglobulin light chain (AL) cardiac amyloidosis

AIMS: Technetium-99m-labelled 3,3-diphosphono-1,2-propanodicarboxylic acid (99mTc-DPD scintigraphy) is recognized as highly accurate for the non-invasive diagnosis of transthyretin (ATTR) cardiac amyloidosis (CA). A proportion of patients with immunoglobulin light chain (AL) CA have also been reported to show cardiac 99mTc-DPD uptake. Herein, we assessed the frequency and degree of cardiac 99mTc-DPD uptake and its clinical significance among patients with AL CA. METHODS AND RESULTS: Between 2010 and 2017, 292 consecutive patients with AL CA underwent 99mTc-DPD scintigraphy and were included in this study: 114 (39%) had cardiac 99mTc-DPD uptake: grade 1 in 75%, grade 2 in 17%, and grade 3 in 8% of cases. Patients with cardiac 99mTc-DPD uptake had poorer cardiac systolic function and higher N-terminal pro-brain natriuretic peptide. No differences were noted in cardiac magnetic resonance parameters between patients with and without cardiac 99mTc-DPD uptake (N = 19 and 42, respectively). Patients with cardiac 99mTc-DPD uptake showed a trend to worse survival than those with no uptake (log-rank P = 0.056). Among 22 patients who underwent serial 99mTc-DPD scintigraphy, 5 (23%) showed reduction in the grade of cardiac uptake. CONCLUSIONS: In this large cohort of patients with AL CA, 99mTc-DPD scintigraphy ∼40% of cases showed cardiac uptake, including grade 2-3 in 10% of all patients (25% of those with cardiac 99mTc-DPD uptake). Cardiac 99mTc-DPD uptake was associated with poorer cardiac function and outcomes. These data highlight the critical importance of ruling out AL amyloidosis in all patients with cardiac 99mTc-DPD uptake to ensure such patients are not assumed to have ATTR CA

Consequences of converting graded to action potentials upon neural information coding and energy efficiency

Information is encoded in neural circuits using both graded and action potentials, converting between them within single neurons and successive processing layers. This conversion is accompanied by information loss and a drop in energy efficiency. We investigate the biophysical causes of this loss of information and efficiency by comparing spiking neuron models, containing stochastic voltage-gated Na+ and K+ channels, with generator potential and graded potential models lacking voltage-gated Na+ channels. We identify three causes of information loss in the generator potential that are the by-product of action potential generation: (1) the voltage-gated Na+ channels necessary for action potential generation increase intrinsic noise and (2) introduce non-linearities, and (3) the finite duration of the action potential creates a ‘footprint’ in the generator potential that obscures incoming signals. These three processes reduce information rates by ~50% in generator potentials, to ~3 times that of spike trains. Both generator potentials and graded potentials consume almost an order of magnitude less energy per second than spike trains. Because of the lower information rates of generator potentials they are substantially less energy efficient than graded potentials. However, both are an order of magnitude more efficient than spike trains due to the higher energy costs and low information content of spikes, emphasizing that there is a two-fold cost of converting analogue to digital; information loss and cost inflation

The phospholipid membrane compositions of bacterial cells, cancer cell lines and biological samples from cancer patients

While cancer now impacts the health and well-being of more of the human population than ever before, the exponential rise in antimicrobial resistant (AMR) bacterial infections means AMR is predicted to become one of the greatest future threats to human health. It is therefore vital that novel therapeutic strategies are developed that can be used in the treatment of both cancer and AMR infections. Whether the target of a therapeutic agent be inside the cell or in the cell membrane, it must either interact with or cross this phospholipid barrier to elicit the desired cellular effect. Here we summarise findings from published research into the phospholipid membrane composition of bacterial and cancer cell lines and biological samples from cancer patients. These data not only highlight key differences in the membrane composition of these biological samples, but also the methods used to elucidate and report the results of this analogous research between the microbial and cancer fields

2'-O-methoxyethyl splice-switching oligos correct splicing from IVS2-745 β-thalassemia patient cells restoring HbA production and chain rebalance

\u3b2-thalassemia is a disorder caused by altered hemoglobin protein synthesis and affects individuals worldwide. Severe forms of the disease, left untreated, can result in death before the age of 3 years (1). The standard of care consists of chronic and costly palliative treatment by blood transfusion combined with iron chelation. This dual approach suppresses anemia and reduces iron-related toxicities in patients. Allogeneic bone marrow transplant is an option, but limited by the availability of a highly compatible HSC donor. While gene therapy is been explored in several trials, its use is highly limited to developed regions with centers of excellence and well-established healthcare systems (2). Hence, there remains a tremendous unmet medical need to develop alternative treatment strategies for \u3b2-thalassemia (3). Occurrence of aberrant splicing is one of the processes that affects \u3b2-globin synthesis in \u3b2-thalassemia. The (C>G) IVS-2-745 is a splicing mutation within intron 2 of the \u3b2-globin gene. It leads to an aberrantly spliced mRNA that incorporates an intron fragment. This results in an in-frame premature termination codon that inhibits \u3b2-globin production. Here, we propose the use of uniform 2'-O-methoxyethyl (2'-MOE) splice switching oligos (SSOs) to reverse this aberrant splicing in the pre-mRNA. With these lead SSOs we show aberrant to wild type splice switching. This switching leads to an increase of adult hemoglobin (HbA) up to 80% in erythroid cells from patients with the IVS-2-745 mutation. Furthermore, we demonstrate a restoration of the balance between \u3b2-like- and \u3b1-globin chains, and up to an 87% reduction in toxic \u3b1-heme aggregates. While examining the potential benefit of 2'-MOE-SSOs in a mixed sickle-thalassemic phenotypic setting, we found reduced HbS synthesis and sickle cell formation due to HbA induction. In summary, 2'-MOE-SSOs are a promising therapy for forms of \u3b2-thalassemia caused by mutations leading to aberrant splicing

Deferred autologous stem cell transplantation in systemic AL amyloidosis

High-dose melphalan with autologous stem cell transplantation (ASCT) can induce durable haematological and organ responses in systemic AL amyloidosis (AL). Stringent selection criteria have improved safety of ASCT in AL but most patients are transplant-ineligible. We report our experience of deferred ASCT in AL patients who were transplant-ineligible at presentation but had improvements in organ function after induction chemotherapy, enabling them to undergo ASCT. Twenty-two AL patients underwent deferred ASCT from 2011 to 2017. All had serial organ function and clonal response assessment. Organ involvement and responses were defined by amyloidosis consensus criteria. All patients were transplant-ineligible at presentation, predominantly due to advanced cardiac involvement. All received bortezomib-based therapy, with 100% haematologic response (86% complete response (CR)/very good partial response (VGPR)), enabling reversal of ASCT exclusion criteria. Patients underwent deferred ASCT for haematologic progression (45%) or consolidation (55%). There was no transplant-related mortality. Haematologic responses post-ASCT: CR 50%, VGPR 27%, PR 18%, non-response 5%. In all, 85.7% achieved cardiac responses. Median overall survival (OS) was not reached. Median progression-free survival (PFS) was 54 months. This selected cohort achieved excellent haematologic responses, organ responses, PFS and OS with deferred ASCT. If larger studies confirm these findings, this may widen the applicability of ASCT in AL