Molecular Characterization of BK Polyomavirus Replication in Allogeneic Hematopoietic Cell Transplantation Patients. (21st November 2022)

• Record Type: Journal Article
• Authors: Leuzinger, Karoline; Kaur, Amandeep; Wilhelm, Maud; Frank, Konstantin; Hillenbrand, Caroline A; Weissbach, Fabian H; Hirsch, Hans H
• Is Part Of: Journal of infectious diseases. Volume 227:Number 7(2023)
• Page Start: 888
• Page End: 900
• Publication Date: 2022-11-21
• Subjects: BK polyomavirus -- BKPyV -- hemorrhagic cystitis -- hematopoietic cell transplantation -- HCT -- T cell -- CD8 -- epitope -- LTag -- Vp1 -- neutralizing antibody -- immune escape; Communicable diseases -- Periodicals; Diseases -- Causes and theories of causation -- Periodicals; Medicine -- Periodicals; Communicable Diseases -- Periodicals; Electronic journals; 616.9
• DOI: 10.1093/infdis/jiac450
• Languages: English
• ISSNs: 0022-1899

Abstract

Abstract: Background: High-level BK polyomavirus (BKPyV) replication in allogeneic hematopoietic cell transplantation (HCT) predicts failing immune control and BKPyV-associated hemorrhagic cystitis. Methods: To identify molecular markers of BKPyV replication and disease, we scrutinized BKPyV DNA-loads in longitudinal urine and plasma pairs from 20 HCT patients using quantitative nucleic acid testing (QNAT), DNase-I treatment prior to QNAT, next-generation sequencing (NGS), and tested cell-mediated immunity. Results: We found that larger QNAT amplicons led to under-quantification and false-negatives results ( P < .001). DNase-I reduced urine and plasma BKPyV-loads by >90% ( P < .001), indicating non-encapsidated BKPyV genomes. DNase-resistant urine BKPyV-loads remained infectious in cell culture. BKPyV genome fragmentation of ≤250 bp impaired NGS coverage of genetic variation using 1000-bp and 5000-bp amplicons. Conversely, 250-bp amplicons captured viral minority variants. We identified genotype-specific and genotype-independent changes in capsid Vp1 or T-antigen predicted to escape from antibody neutralization or cytotoxic CD8 T-cells, respectively. Genotype-specific changes in immunodominant 9mers were associated with reduced or absent CD8 T-cell responses. Thus, failure to control BKPyV replication in HCT Patients may involve insufficient genotype-specific cytotoxic CD8 T-cell responses, potentially predictable by low neutralizing antibodies as well as genotype-independent immune escape. Conclusions: Our results provide new insights for patient evaluation and for designing immune protection through neutralizing antibodies, adoptive T-cell therapy, or vaccines. Abstract : BKPyV genome loads in allogeneic hematopoietic cell transplantation are DNase-I sensitive, nonencapsidated DNA fragments of ≤250 bp. This can impair detection of BKPyV diversity by next-generation sequencing and specifically genotype-associated changes mediating BKPyV immune escape from cytotoxic CD8 T-cell killing.