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BACKGROUND. Adoptive transfer of EBV-specific T cells can restore specific immunity in immunocompromised patients with EBV-associated complications. METHODS. We provide results of a personalized T cell manufacturing program evaluating donor, patient, T cell product, and outcome data. Patient-tailored clinical-grade EBV-specific cytotoxic T lymphocyte (EBV-CTL) products from stem cell donors (SCDs), related third-party donors (TPDs), or unrelated TPDs from the allogeneic T cell donor registry (alloCELL) at Hannover Medical School were manufactured by immunomagnetic selection using a CliniMACS Plus or Prodigy device and the EBV PepTivators EBNA-1 and Select. Consecutive manufacturing processes were evaluated, and patient outcome and side effects were retrieved by retrospective chart analysis. RESULTS. Forty clinical-grade EBV-CTL products from SCDs, related TPDs, or unrelated TPDs were generated for 37 patients with refractory EBV infections or EBV-associated malignancies with and without a history of transplantation, within 5 days (median) after donor identification. Thirty-four patients received 1-14 EBV-CTL products (fresh and cryopreserved). EBV-CTL transfer led to a complete response in 20 of 29 patients who were evaluated for clinical response. No infusion-related toxicity was reported. EBV-specific T cells in patients' blood were detectable in 16 of 18 monitored patients (89%) after transfer, and their presence correlated with clinical response. CONCLUSION. Personalized clinical-grade manufacture of EBV-CTL products via immunomagnetic selection from SCDs, related TPDs, or unrelated TPDs in a timely manner is feasible. Overall, EBV-CTLs were clinically effective and well tolerated. Our data suggest EBV-CTL transfer as a promising therapeutic approach for immunocompromised patients with refractory EBV-associated diseases beyond HSCT, as well as patients with preexisting organ dysfunction. TRIAL REGISTRATION. Not applicable. FUNDING. This study was funded in part by the German Research Foundation (DFG, 158989968/SFB 900), the Deutsche Kinderkrebsstiftung (DKS 2013.09), Wilhelm-Sander-Stiftung (reference 2015.097.1), Ellen-Schmidt-Program of Hannover Medical School, and German Federal Ministry of Education and Research (reference 01E00802)., Introduction Morbidity and mortality in patients with hematopoietic stem cell transplant (HSCT) and solid organ transplant (SOT) are frequently caused by graft rejection or graft-versus-host disease (GvHD) and increased by [...]

Complications due to HCMV infection or reactivation remain a challenging clinical problem in immunocompromised patients, mainly due to insufficient or absent T‐cell functionality. Knowledge of viral targets is crucial to improve monitoring of high‐risk patients and optimise antiviral T‐cell therapy. To expand the epitope spectrum, genetically‐engineered dendritic cells (DCs) and fibroblasts were designed to secrete soluble (s)HLA‐A*11:01 and infected with an HCMV mutant lacking immune evasion molecules (US2‐6 + 11). More than 700 HLA‐A*11:01‐restricted epitopes, including more than 50 epitopes derived from a broad range of HCMV open‐reading‐frames (ORFs) were identified by mass spectrometry and screened for HLA‐A*11:01‐binding using established prediction tools. The immunogenicity of the 24 highest scoring new candidates was evaluated in vitro in healthy HLA‐A*11:01+/HCMV+ donors. Thus, four subdominant epitopes and one immunodominant epitope, derived from the anti‐apoptotic protein UL36 and ORFL101C (A11SAL), were identified. Their HLA‐A*11:01 complex stability was verified in vitro. In depth analyses revealed highly proliferative and cytotoxic memory T‐cell responses against A11SAL, with T‐cell responses comparable to the immunodominant HLA‐A*02:01‐restricted HCMVpp65NLV epitope. A11SAL‐specific T cells were also detectable in vivo in immunosuppressed transplant patients and shown to be effective in an in vitro HCMV‐infection model, suggesting their crucial role in inhibiting viral replication and improvement of patient's outcome. The developed in vitro pipeline is the first to utilise genetically‐engineered DCs to identify naturally presented immunodominant HCMV‐derived epitopes. It therefore offers advantages over in silico predictions, is transferable to other HLA alleles, and will significantly expand the repertoire of viral targets to improve therapeutic options. [ABSTRACT FROM AUTHOR]

Opportunistic viral infections in individuals with severe immunodeficiency can lead to fatal conditions such as progressive multifocal leukoencephalopathy (PML), for which treatment options are limited. These infections pose significant risks, especially when co-infections with other viruses occur. We describe a combined therapy approach using directly isolated allogeneic Human Polyomavirus 1 (also known as BKV) and Epstein–Barr virus (EBV) specific cytotoxic T-cells for the treatment of PML in conjunction with identified EBV in the cerebrospinal fluid (CSF) of a male patient infected with human immunodeficiency virus (HIV). A 53-year-old HIV-positive male, recently diagnosed with PML, presented with rapidly worsening symptoms, including ataxia, tetraparesis, dysarthria, and dysphagia, leading to respiratory failure. The patient developed PML even after commencing highly active antiretroviral therapy (HAART) 3 months prior. Brain magnetic resonance imaging (MRI) revealed multifocal demyelination lesions involving the posterior fossa and right thalamus suggestive of PML. In addition to the detection of human polyomavirus 2 (also known as JCV), analysis of CSF showed positive results for EBV deoxyribonucleic acid (DNA). His neurological condition markedly deteriorated over the following 2 months. Based on MRI, there was no evidence of Immune Reconstitution Inflammatory Syndrome contributing to this decline. The patient did not have endogenous virus-specific T-cells. We initiated an allogeneic, partially human leukocyte antigen-matched transfer of EBV and utilizing the cross-reactivity between BKV and JCV–BKV specific T-cells. This intervention led to notable neurological improvement and partial resolution of the MRI lesions within 6 weeks. Our case of a patient with acquired immune deficiency syndrome demonstrates that PML and concurrent EBV co-infection can still occur despite undergoing HAART treatment. This innovative experimental therapy, involving a combination of virus-specific T-cells, was demonstrated to be an effective treatment option in this patient. [ABSTRACT FROM AUTHOR]

Salinity is an increasing problem in coastal areas affected by saltwater intrusion, with deleterious effects on tree health and forest growth. Ectomycorrhizal (ECM) fungi may improve the salinity tolerance of host trees, but the impact of external potassium (K+) availability on these effects is still unclear. Here, we performed several experiments with the ECM fungus Paxillus ammoniavirescens and loblolly pine (Pinus taeda L.) in axenic and symbiotic conditions at limited or sufficient K+ and increasing sodium (Na+) concentrations. Growth rate, biomass, nutrient content, and K+ transporter expression levels were recorded for the fungus, and the colonization rate, root development parameters, biomass, and shoot nutrient accumulation were determined for mycorrhizal and non‐mycorrhizal plants. P. ammoniavirescens was tolerant to high salinity, although growth and nutrient concentrations varied with K+ availability and increasing Na+ exposure. While loblolly pine root growth and development decreased with increasing salinity, ECM colonization was unaffected by pine response to salinity. The mycorrhizal influence on loblolly pine salinity response was strongly dependent on external K+ availability. This study reveals that P. ammoniavirescens can reduce Na+ accumulation of salt‐exposed loblolly pine, but this effect depends on external K+ availability. [ABSTRACT FROM AUTHOR]