Efficient removal of antibodies to adeno-associated viruses by immunoadsorption.

BACKGROUND: Gene therapies based on adeno-associated viruses (AAV) are a therapeutic option to successfully treat monogenetic diseases. However, the influence of pre-existing immunity to AAV can compromise the application of AAV gene therapy, most notably by the presence of neutralizing antibodies (NAb) to AAV. METHODS: In the following study, we investigated to what extent the treatment by immunoadsorption (IA) would reduce the levels of human anti-AAV antibodies to AAV2 and AAV5. To that end, we screened blood sera from 40 patients receiving IA treatment because of underlying autoimmune disease or transplant rejection, with detectable AAV-antibodies in 23 patients (22 by NAb detection, and 1 additionally by anti-AAV5 ELISA analysis). RESULTS: Our results show that IA efficiently depleted anti-AAV2 NAb with a mean reduction of 3.92 ± 1.09 log2 titer steps (93.4%) after three to five single IA treatments, 45% of seropositive subjects had an anti-AAV2 titer below the threshold titer of 1:5 after the IA treatment series. Anti-AAV5 NAb were reduced to below the threshold titer of 1:5 in all but one of five seropositive subjects. Analysis of total anti-AAV5 antibodies by ELISA demonstrated an anti-AAV5 antibody reduction over the IA treatment series of 2.67 ± 1.16 log2 titer steps (84.3%). CONCLUSION: In summary, IA may represent a safe strategy to precondition patients with pre-existing anti-AAV antibodies to make this population eligible for an effective AAV-based gene therapy.

Case Report of Anti-Thrombogenicity.

BACKGROUND: The Toray Filtryzer™-NF is a new polymethyl methacrylate filter with improved hemocompatibility and reduced impact on platelet counts. OBJECTIVES: This suggests that, if necessary, a reduction in anticoagulation may be possible when dialysis is performed with the Toray Filtryzer™-NF. METHODS: In the following, we dialyzed 5 hemodialysis patients who had a contraindication to full anticoagulation postoperatively or after renal biopsy with the Filtryzer™-NF. RESULTS: A significant reduction in heparin administration was achieved, and in 1 patient, heparin substitution was completely omitted. Despite the significantly reduced heparin doses, no thrombosis of the system occurred during the hemodialysis. CONCLUSION: In conclusion, hemodialysis using the Toray Filtryzer™-NF is an effective alternative for patients at significantly increased risk of bleeding.

Influence of Advanced Organ Support (ADVOS) on Cytokine Levels in Patients with Acute-on-Chronic Liver Failure (ACLF).

Background: ADVanced Organ Support (ADVOS) is a novel type of extracorporeal albumin dialysis that supports multiorgan function in patients with acute-on-chronic liver failure (ACLF). No data exist on whether ADVOS affects inflammatory cytokine levels, which play a relevant role in ACLF. Aim: Our aim was to quantify cytokine levels both before and after a single ADVOS treatment in patients with ACLF at a regular dialysis ward. Methods and results: In this prospective study, 15 patients (60% men) with ACLF and an indication for renal replacement therapy were included. Patient liver function was severely compromised, reflected by a median CLIF-consortium ACLF score of 38 (IQR 35; 40). Blood samples were directly taken before and after ADVOS dialysis. The concentration of cytokines for IL-1ß, IFN-α2, IFN-γ, TNF-α, MCP-1, IL-6, IL-8, IL-10, IL-12p70, IL-17A, IL-18, IL-23, IL-33 were quantified via a cytometric bead array. We found no significant (p > 0.05) change in cytokine levels, even when patients were stratified for dialysis time (<480 min versus ≥480 min). The relevance of the assessed cytokines in contributing to systemic inflammation in ACLF was demonstrated by Ingenuity pathway analysis®. Conclusion: Concentrations of pathomechanistically relevant cytokines remained unchanged both before and after ADVOS treatment in patients with ACLF.

Six-Month Follow-Up after Vaccination with BNT162b2: SARS-CoV-2 Antigen-Specific Cellular and Humoral Immune Responses in Hemodialysis Patients and Kidney Transplant Recipients.

Hemodialysis patients (HDP) and kidney transplant recipients (KTR) have a high risk of infection with SARS-CoV-2 with poor clinical outcomes. Because of this, vaccination of these groups of patients against SARS-CoV-2 is particularly important. However, immune responses may be impaired in immunosuppressed and chronically ill patients. Here, our aim was to compare the efficacy of an mRNA-based vaccine in HDP, KTR, and healthy subjects. DESIGN: In this prospective observational cohort study, the humoral and cellular response of prevalent 192 HDP, 50 KTR, and 28 healthy controls (HC) was assessed 1, 2, and 6 months after the first immunization with the BNT162b2 mRNA vaccine. RESULTS: After 6 months, 97.5% of HDP, 37.9% of KTR, and 100% of HC had an antibody response. Median antibody levels were 1539.7 (±3355.8), 178.5 (±369.5), and 2657.8 (±2965.8) AU/mL in HDP, KTR, and HC, respectively (p ≤ 0.05). A SARS-CoV-2 antigen-specific cell response to vaccination was found in 68.8% of HDP, 64.5% of KTR, and 90% of HC. CONCLUSION: The humoral response rates to mRNA-based vaccination of HDPs are comparable to HCs, but antibody titers are lower. Furthermore, HDPs have weaker T-cell response to vaccination than HCs. KTRs have very low humoral and antigen-specific cellular response rates and antibody titers, which requires other vaccination strategies in addition to booster vaccination.

Immunoadsorption and plasma exchange-Efficient treatment options for neurological autoimmune diseases.

BACKGROUND: Therapeutic plasma exchange (TPE) and immunoadsorption (IA) are first or second line treatment options in patients with neurological autoimmune diseases, including multiple sclerosis, neuromyelitis optica spectrum disorders (NMSOD), chronic inflammatory demyelinating polyneuropathy, acute inflammatory demyelinating polyradiculoneuropathy (Guillain-Barré syndrome), and autoimmune encephalitis. METHODS: In this prospective randomized controlled monocentric study, we assessed safety and efficacy of therapy with IA or TPE in patients with neurological autoimmune diseases. Treatment response was assessed using various neurological scores as well by measuring immunoglobulin and cytokine concentrations. Clinical outcome was evaluated by application of specific scores for the underlying diseases. RESULTS: A total of 32 patients were analyzed. Among these, 19 patients were treated with TPE and 13 patients with IA. IA and TPE therapy showed a comparable significant treatment response. In patients with MS and NMOSD, mean EDSS before and after treatment showed a significant reduction after treatment with IA. We observed a significant reduction of the pro-inflammatory cytokines IL-12, lL-17, IL-6, INF-γ, and tumor necrosis factor alpha during IA treatment, whereas this reduction was not seen in patients treated with TPE. CONCLUSIONS: In summary, both IA and TPE were effective and safe procedures for treating neurological autoimmune diseases. However, there was a trend towards longer therapy response in patients treated with IA compared to TPE, possibly related to a reduction in plasma levels of pro-inflammatory cytokines seen only in the IA-treated group.

Treatment of Membranous Nephropathy in Patients With THSD7A Antibodies Using Immunoadsorption.

Antibodies against THSD7A (thrombospondin type 1 domain-containing protein 7A) have been proposed to play a causal role in the development of nephrotic syndrome in patients with THSD7A antibody-positive membranous nephropathy. We hypothesized that removal of these antibodies from plasma could lead to a rapid reduction in proteinuria. Using immunoadsorption to reduce THSD7A antibodies led to a rapid reduction in proteinuria in 2 patients with THSD7A antibody-positive membranous nephropathy. Moreover, our findings support and strengthen the pathogenic role of the antibodies in the development of nephrotic syndrome in patients with THSD7A antibody-positive membranous nephropathy. Taken together, these 2 cases suggest that immunoadsorption could be a useful tool in the treatment of patients with THSD7A antibody-positive membranous nephropathy.