PRODUCTION OF THEORETICAL TTV CAPSID PROTEIN IN E. COLI

Gabija Klimavičiūtė1, Uršulė Simonaitytė1, Martynas Simanavičius1

1 Department of Immunology, Institute of Biotechnology, Life Sciences Center, Vilnius University

[email protected]

Torque teno virus (TTV) is a part of human virome. TTV is under active investigation as a marker of immunocompetence. After a solid organ transplant (SOT), patients are treated with immunosuppressants to reduce the immune response. However, if immunosuppression is not optimal, the risk of infection or organ rejection is higher, and the patient’s health could be at risk. Therefore, a reliable molecular marker of immunosuppression is needed. Previous studies in this area have reported that TTV levels are elevated in the blood of SOT patients, making it a potential marker for monitoring the level of immunosuppression [1].

TTV is a small, non-enveloped, single-stranded DNA virus of the Anelloviridae family. The TTV genome consists of at least 6 open reading frames (ORFs), of which ORF1 is the longest [2]. It encodes the putative TTV capsid protein ORF1, which exposes antigenic peptides in its C-terminus and is recognized by antibodies [3]. The aim of this study is to achieve the bacterial synthesis of recombinant putative TTV capsid protein. A gene sequence was selected and the gene encoding the required protein was acquired based on the epitopes identified in the literature. The gene construct was chosen for its ability to allow gene expression in bacteria, followed by potentially soluble protein synthesis [3][4]. A gene expression vector was selected, and protein synthesis was confirmed by Western blot.

In conclusion, the synthesis of a putative TTV capsid protein has been achieved. Future plans include protein purification, mice immunization, and the development of monoclonal antibodies specific to this protein as universal tools for detection of TTV in patient samples.


[1] van Rijn, A., Roos, R., Dekker, F., Rotmans, J., & Feltkamp, M. (2023). Torque teno virus load as marker of rejection and infection in solid organ transplantation – A systematic review and meta-analysis. Reviews in Medical Virology, 33(1), e2393. https://doi.org/10.1002/rmv.2393

[2] Rezahosseini, O., Drabe, C. H., Sørensen, S. S., Rasmussen, A., Perch, M., Ostrowski, S. R., & Nielsen, S. D. (2019). Torque-Teno virus viral load as a potential endogenous marker of immune function in solid organ transplantation. Transplantation Reviews (Orlando, Fla.), 33(3), 137–144. https://doi.org/10.1016/j.trre.2019.03.004

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