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. 2022 May 13;19(1):79.
doi: 10.1186/s12985-022-01812-3.

Plasma Torquetenovirus (TTV) microRNAs and severity of COVID-19

Maria Alfreda Stincarelli  1 , Andreina Baj  2 , Bernardo Guidotti  1 , Pietro Giorgio Spezia  3 , Federica Novazzi  2 , Ersilia Lucenteforte  4 , Silvia Tillati  4 , Daniele Focosi  5 , Fabrizio Maggi  2 , Simone Giannecchini  6
Affiliations

Plasma Torquetenovirus (TTV) microRNAs and severity of COVID-19

Maria Alfreda Stincarelli et al. Virol J. .

Abstract

Background: Torquetenovirus (TTV), a widespread anellovirus recognized as the main component of the healthy human virome, displays viremia that is highly susceptible to variations in immune competence. TTV possesses microRNA (miRNA)-coding sequences that might be involved in viral immune evasion. Among TTV-encoded miRNAs, miRNA t1a, t3b, and tth8 have been found in biological fluids. Here, the presence of TTV DNA and TTV miRNAs in the plasma of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected subjects was investigated to monitor the possible association with coronavirus disease 2019 (COVID-19) severity.

Methods: Detection of TTV DNA and miRNA t1a, t3b, and tth8 was investigated in plasma samples of 56 SARS-CoV-2-infected subjects with a spectrum of different COVID-19 outcomes. TTV DNA and TTV miRNAs were assessed with a universal single step real-time TaqMan PCR assay and miRNA quantitative RT-PCR miRNA assay, respectively.

Results: The TTV DNA prevalence was 59%, whereas at least one TTV miRNA was found in 94% of the patients tested. miRNA tth8 was detected in 91% of subjects, followed by miRNAs t3b (64%) and miRNAt1a (30%). Remarkably, although TTV DNA was unrelated to COVID-19 severity, miRNA tth8 was significantly associated with the degree of disease (adjusted incidence rate ratio (IRR) 2.04, 95% CI 1.14-3.63, for the subjects in the high severity group compared to those in the low severity group).

Conclusions: Our findings encourage further investigation to understand the potential role of TTV miRNAs in the different outcomes of COVID-19 at early and late stages.

Keywords: Anelloviridae; COVID-19; Inflammatory response; MicroRNA expression; SARS-CoV-2; Torquetenovirus.

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Conflict of interest statement

We declare we have no conflict of interest related to this manuscript.

Figures

Fig. 1
Fig. 1
TTV DNA and miRNA quantification according to the WHO score of study subjects. Among the 27 samples with WHO ≥ 5, 15 (55%), 7 (26%), 20 (74%), and 27 (100%) were positive for TTV DNA, TTV miRNA t1a, TTV miRNA t3b, and TTV miRNA tth8, respectively. Among the 29 samples with WHO < 5, 18 (62%), 10 (34%), 16 (55%), and 24 (82%) were positive for TTV DNA, TTV miRNA t1a, TTV miRNA t3b, and TTV miRNA tth8, respectively. The mean ± standard deviation (SD) for the positive samples for TTV DNA, TTV miRNA t1a, TTV miRNA t3b, and TTV miRNA tth8 is also reported
See this image and copyright information in PMC

References

    1. Arze CA, Springer S, Dudas G, Patel S, Bhattacharyya A, Swaminathan H, Brugnara C, Delagrave S, Ong T, Kahvejian A, Echelard Y, Weinstein EG, Hajjar RJ, Andersen KG, Yozwiak NL. Global genome analysis reveals a vast and dynamic anellovirus landscape within the human virome. Cell Host Microbe. 2021;29:1305–1315. doi: 10.1016/j.chom.2021.07.001. - DOI - PubMed
    1. Kaczorowska J, van der Hoek L. Human anelloviruses: diverse, omnipresent and commensal members of the virome. FEMS Microbiol Rev. 2020;44:305–313. doi: 10.1093/femsre/fuaa007. - DOI - PMC - PubMed
    1. Focosi D, Antonelli G, Pistello M, Maggi F. Torquetenovirus: the human virome from bench to bedside. Clin Microbiol Infect. 2016;22:589–593. doi: 10.1016/j.cmi.2016.04.007. - DOI - PubMed
    1. Nishizawa T, Okamoto H, Konishi K, Yoshizawa H, Miyakawa Y, Mayumi M. A novel DNA virus (TTV) associated with elevated transaminase levels in post-transfusion hepatitis of unknown etiology. Biochem Biophys Res Commun. 1997;241:92–97. doi: 10.1006/bbrc.1997.7765. - DOI - PubMed
    1. Okamoto H. History of discoveries and pathogenicity of TT viruses. Curr Top Microbiol Immunol. 2009;331:1–20. - PubMed

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