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Träfflista för sökning "WFRF:(Hellstrand Kristoffer 1956) ;pers:(Törnell Andreas 1994)"

Search: WFRF:(Hellstrand Kristoffer 1956) > Törnell Andreas 1994

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1.
  • Einarsdottir, Sigrun, et al. (author)
  • Deficiency of SARS-CoV-2 T-cell responses after vaccination in long-term allo-HSCT survivors translates into abated humoral immunity.
  • 2022
  • In: Blood advances. - : American Society of Hematology. - 2473-9537 .- 2473-9529. ; 6:9, s. 2723-2730
  • Journal article (peer-reviewed)abstract
    • Recipients of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for hematological diseases are at risk of severe disease and death from COVID-19. To determine the safety and immunogenicity of BNT162b2 and mRNA-1273 COVID-19 vaccines, samples from 50 infection-naive allo-HSCT recipients (median, 92 months from transplantation, range, 7-340 months) and 39 healthy controls were analyzed for serum immunoglobulin G (IgG) against the receptor binding domain (RBD) within spike 1 (S1) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; anti-RBD-S1 IgG) and for SARS-CoV-2-specific T-cell immunity, reflected by induction of T-cell-derived interferon-γ in whole blood stimulated ex vivo with 15-mer SI-spanning peptides with 11 amino acid overlap S1-spanning peptides. The rate of seroconversion was not significantly lower in allo-transplanted patients than in controls with 24% (12/50) and 6% (3/50) of patients remaining seronegative after the first and second vaccination, respectively. However, 58% of transplanted patients lacked T-cell responses against S1 peptides after 1 vaccination compared with 19% of controls (odds ratio [OR] 0.17; P = .009, Fisher's exact test) with a similar trend after the second vaccination where 28% of patients were devoid of detectable specific T-cell immunity, compared with 6% of controls (OR 0.18; P = .02, Fisher's exact test). Importantly, lack of T-cell reactivity to S1 peptides after vaccination heralded substandard levels (<100 BAU/mL) of anti-RBD-S1 IgG 5 to 6 months after the second vaccine dose (OR 8.2; P = .007, Fisher's exact test). We conclude that although allo-HSCT recipients achieve serum anti-RBD-S1 IgG against SARS-CoV-2 after 2 vaccinations, a deficiency of SARS-CoV-2-specific T-cell immunity may subsequently translate into insufficient humoral responses.
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2.
  • Martner, Anna, 1979, et al. (author)
  • Transient and durable T cell reactivity after COVID-19
  • 2022
  • In: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424. ; 119:30
  • Journal article (peer-reviewed)abstract
    • This study analyzed whole blood samples (n = 56) retrieved from 30 patients at 1 to 21 (median 9) mo after verified COVID-19 to determine the polarity and duration of antigen-specific T cell reactivity against severe acute respiratory syndrome coronavirus 2-derived antigens. Multimeric peptides spanning the entire nucleocapsid protein triggered strikingly synchronous formation of interleukin (IL)-4, IL-12, IL-13, and IL-17 ex vivo until similar to 70 d after confirmed infection, whereafter this reactivity was no longer inducible. In contrast, levels of nucleocapsid-induced IL-2 and interferon-gamma remained stable and highly correlated at 3 to 21 mo after infection. Similar cytokine dynamics were observed in unvaccinated, convalescent patients using whole-blood samples stimulated with peptides spanning the N-terminal portion of the spike 1 protein. These results unravel two phases of T cell reactivity following natural COVID-19: an early, synchronous response indicating transient presence of multipolar, antigen-specific T helper (T-H) cells followed by an equally synchronous and durable T(H)1-like reactivity reflecting long-lasting T cell memory.
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3.
  • Törnell, Andreas, 1994, et al. (author)
  • CYBA allelic variants are associated with severity and recovery in Guillain-Barré syndrome
  • 2023
  • In: Journal of the peripheral nervous system. - 1085-9489. ; 28:3, s. 407-414
  • Journal article (peer-reviewed)abstract
    • Background and Aims: Guillain–Barré syndrome (GBS) is a rare, acute neuropathy characterized by ascending muscle weakness. Age, axonal GBS variants, and antecedent Campylobacter jejuni infection are associated with severe GBS, but the detailed mechanisms of nerve damage are only partly explored. Pro-inflammatory myeloid cells express NADPH oxidases (NOX) that generate tissue-toxic reactive oxygen species (ROS) that are implicated in neurodegenerative diseases. This study analyzed the impact of variants of the gene encoding the functional NOX subunit CYBA (p22phox) on acute severity, axonal damage, and recovery in adult GBS patients. Methods: Extracted DNA from 121 patients was genotyped for allelic variation at rs1049254 and rs4673 within CYBA using real-time quantitative polymerase chain reaction. Serum neurofilament light chain was quantified by single molecule array. Patients were followed for severity and motor function recovery for up to 13 years. Results: CYBA genotypes linked to reduced formation of ROS, i.e. rs1049254/G and rs4673/A, were significantly associated with unassisted ventilation, shorter time to normalization of serum neurofilament light chain and shorter time to regained motor function. Residual disability at follow-up was confined to patients carrying CYBA alleles associated with high formation of ROS. Interpretation: These findings implicate NOX-derived ROS in GBS pathophysiology and CYBA alleles as biomarkers of severity.
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4.
  • Törnell, Andreas, 1994, et al. (author)
  • Induction and subsequent decline of S1-specific T cell reactivity after COVID-19 vaccination
  • 2023
  • In: Clinical Immunology. - : Elsevier BV. - 1521-6616. ; 248
  • Journal article (peer-reviewed)abstract
    • We analyzed magnitude and duration of SARS-CoV-2-specific T cell responses in healthy, infection-naive subjects receiving COVID-19 vaccines. Overlapping peptides spanning the N-terminal spike 1 (S1) domain of the spike protein triggered secretion of the T cell-derived cytokine interleukin-2 ex vivo in 94/94 whole blood samples from vaccinated subjects at levels exceeding those recorded in all 45 pre-vaccination samples. S1-specific T cell reactivity was stronger in vaccinated subjects compared with subjects recovering from natural COVID-19 and decayed with an estimated half-life of 134 days in the first six months after the 2nd vaccination. We conclude that COVID-19 vaccination induces robust T cell immunity that subsequently declines.EudraCT 2021-000349-42. https://www.clinicaltrialsregister.eu/ctr-search/search?query=2021-000349-42
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5.
  • Törnell, Andreas, 1994, et al. (author)
  • Rapid cytokine release assays for analysis of SARS-CoV-2-specific T cells in whole blood.
  • 2022
  • In: The Journal of infectious diseases. - : Oxford University Press (OUP). - 1537-6613 .- 0022-1899. ; 226:2, s. 208-216
  • Journal article (peer-reviewed)abstract
    • Waning of IgG antibodies against SARS-CoV-2 complicates diagnosis of past infection. Durability of T cell memory against SARS-CoV-2 remains unclear, and most current T cell protocols are unsuited for large-scale automation.Whole blood samples from 31 patients with verified past COVID-19 and 46 controls, out of which 40 received SARS-CoV-2 vaccine were stimulated with peptides spanning the nucleocapsid (NC) or spike 1 (S1) regions of SARS-CoV-2 and analyzed for interferon-γ (IFN-γ) in supernatant plasma. Diagnostic accuracy of these assays was evaluated against serum anti-NC and anti-receptor-binding domain S1 IgG.Induction of IFN-γ in whole blood by NC or S1 peptides diagnosed past COVID-19 with high accuracy (AUC=0.93, AUC=0.95, respectively). In accordance with previous studies, NC-IgG levels rapidly waned with only 5/17 patients (29%) remaining seropositive >180 days after infection. By contrast, NC-peptide-induced T cell memory responses remained in 13/17 (76%) subjects >180 days after infection (P=0.012 vs. NC-IgG, McNemar test). After two vaccine doses, 18/18 donors exhibited S1-specific T cell memory.Cytokine release assays for the monitoring of T cell memory in whole blood may be useful for evaluation of complications following unverified past COVID-19 and for long-term assessment of vaccine-induced T cell immunity.
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6.
  • Al-Dury, Samer, et al. (author)
  • Impaired SARS-CoV-2-specific T-cell reactivity in patients with cirrhosis following mRNA COVID-19 vaccination
  • 2022
  • In: JHEP Reports. - : Elsevier BV. - 2589-5559. ; 4:7
  • Journal article (peer-reviewed)abstract
    • Background & Aims: Cirrhosis entails elevated risk of COVID-19-associated mortality. This study determined T cell-mediated and antibody reactivity against the spike 1 (S1) protein of SARS-CoV-2 among 48 patients with cirrhosis and 39 healthy controls after mRNA COVID-19 vaccination. Methods: SARS-CoV-2-specific T-cell reactivity was measured by induced level of T cell-derived interferon-gamma (IFN-gamma) in blood cells stimulated ex vivo with multimeric peptides spanning the N-terminal portion of S1. S1-induced IFN-gamma was quantified before and after the 1st and 2nd vaccination (BNT162b2, Pfizer-BioNTech or mRNA-1273, Moderna) alongside serum IgG against the receptor-binding domain (RBD) within S1 (anti-RBD-S1 IgG). Results: T-cell reactivity against S1 was reduced in patients with cirrhosis after the 1st (p < 0.001 vs. controls) and 2nd (p < 0.001) vaccination. Sixty-eight percent of patients lacked detectable S1-specific T-cell reactivity after the 1st vaccination vs. 19% in controls (odds ratio 0.11, 95% CI 0.03-0.48, p = 0.003) and 36% remained devoid of reactivity after the 2nd vaccination vs. 6% in controls (odds ratio 0.12, 95% CI 0.03-0.59, p = 0.009). T-cell reactivity in cirrhosis remained significantly impaired after correction for potential confounders in multivariable analysis. Advanced cirrhosis (Child-Pugh class B) was associated with absent or lower T-cell responses (p < 0.05 vs. Child-Pugh class A). The deficiency of T-cell reactivity was paralleled by lower levels of anti-RBD-S1 IgG after the 1st (p < 0.001 vs. controls) and 2nd (p < 0.05) vaccination. Conclusions: Patients with cirrhosis show deficient T-cell reactivity against SARS-CoV-2 antigens along with diminished levels of anti-RBD-S1 IgG after dual COVID-19 vaccination, highlighting the need for vigilance and additional preventative measures. Clinical trial registration: EudraCT 2021-000349-42 Lay summary: T cells are a pivotal component in the defence against viruses. We show that patients with cirrhosis have impaired SARS-CoV-2-specific T-cell responses and lower antibody levels after mRNA vaccination against COVID-19 compared with healthy controls. Patients with more advanced liver disease exhibited particularly inferior vaccine responses. These results call for additional preventative measures in these patients. (C) 2022 The Author(s). Published by Elsevier B.V. on behalf of European Association for the Study of the Liver (EASL).
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9.
  • Törnell, Andreas, 1994, et al. (author)
  • Impact of CYBA genotypes on severity and progression of multiple sclerosis
  • 2022
  • In: European Journal of Neurology. - : Wiley. - 1351-5101 .- 1468-1331. ; 29:5, s. 1457-1464
  • Journal article (peer-reviewed)abstract
    • Background and purpose: The NOX2 enzyme of myeloid cells generates reactive oxygen species (ROS) that have been implicated in the pathology of multiple sclerosis (MS). We aimed to determine the impact of genetic variation within CYBA, which encodes the functional CYBA/p22phox subunit of NOX2, on MS severity and progression. Methods: One hundred three MS patients with up to 49 (median = 17) years follow-up time from first MS diagnosis were genotyped at the single nucleotide polymorphisms rs1049254 and rs4673 within CYBA. Results were matched with disease severity and time to diagnosis of secondary progressive MS (SPMS). NOX2-mediated formation of ROS was measured by chemiluminescence in blood myeloid cells from healthy donors (n = 55) with defined genotypes at rs1049254 and rs4673. Results: The rs1049254/G and rs4673/A CYBA alleles were associated with reduced formation of ROS and were thus defined as low-ROS alleles. Patients carrying low-ROS alleles showed reduced multiple sclerosis severity score (p = 0.02, N = 103, linear regression) and delayed onset of SPMS (p = 0.02, hazard ratio [HR] = 0.46, n = 100, log-rank test). In a cohort examined after 2005, patients carrying low-ROS CYBA alleles showed >20 years longer time to secondary progression (p = 0.003, HR = 0.29, n = 59, log-rank test). Conclusions: These results implicate NOX2 in MS, in particular for the development of secondary progressive disease, and point toward NOX2-reductive therapy aiming to delay secondary progression.
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10.
  • Törnell, Andreas, 1994, et al. (author)
  • Presence of MDSC associates with impaired antigen-specific T cell reactivity following COVID-19 vaccination in cirrhotic patients
  • 2023
  • In: Frontiers in Immunology. - 1664-3224. ; 14
  • Journal article (peer-reviewed)abstract
    • Background and aims: Cirrhosis entails high risk of serious infections and abated efficiency of vaccination, but the underlying mechanisms are only partially understood. This study aimed at characterizing innate and adaptive immune functions, including antigen-specific T cell responses to COVID-19 vaccination, in patients with compensated and decompensated cirrhosis. Methods: Immune phenotype and function in peripheral blood from 42 cirrhotic patients and 44 age-matched healthy controls were analysed after two doses of the mRNA-based COVID-19 vaccines [BNT162b2 (Pfizer BioNTech) or mRNA-1273 (Moderna)]. Results: Cirrhotic patients showed significantly reduced blood counts of antigen-presenting dendritic cells (DC) and high counts of monocytic myeloid-derived suppressor cells (M-MDSC) as compared to healthy controls. In addition, monocytic cells recovered from cirrhotic patients showed impaired expression of the antigen-presenting molecule HLA-DR and the co-stimulatory molecule CD86 upon Toll-like receptor (TLR) stimulation. These features were more prominent in patients with decompensated cirrhosis (Child-Pugh classes B & C). Interestingly, while patients with compensated cirrhosis (Child-Pugh class A) showed an inflammatory profile with myeloid cells producing the proinflammatory cytokines IL-6 and TNF, decompensated patients produced reduced levels of these cytokines. Cirrhotic patients, in particular those with more advanced end-stage liver disease, mounted reduced antigen-specific T cell reactivity to COVID-19 vaccination. Vaccine efficiency inversely correlated with levels of M-MDSC. Conclusion: These results implicate MDSC as mediators of immunosuppression, with ensuing deficiency of vaccine-specific T cell responses, in cirrhosis.
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