Determination of TTV viral load in biological material of target patient groups using a molecular genetic method
https://doi.org/10.29235/1029-8940-2026-71-2-144-156
Abstract
As a result of the conducted research, a target of the Torque Teno Virus (TTV) genome was selected, a set of primers and a TaqMan probe were developed flanking a conserved region of 111 nucleotide pairs (nucleotide positions 103–213 of the TTV reference genome TA278 GenBank: AB017610.1). This probe formed the basis of a molecular genetic method for diagnosing TTV infection, allowing for the detection and calculation of TTV viral load in human biological material. Using the developed molecular genetic method, a high frequency of TTV DNA detection was detected in plasma (71.4–90.4 %) and in the leukocyte fraction of blood (81.0–97.1 %), in both in the control group and in patients afflicted with secondary immunodeficiency, with HIV infection, and severe COVID-19 infection. The TTV viral load in the target groups was determined. A significantly lower median TTV viral load was found in the leukocyte fraction of blood in the control group – 2.58 [1.66; 3.25] log10 TTV DNA copies/105 cells, than in the group of patients with secondary immunodeficiency – 3.67 [1.88; 4.47] log10 TTV DNA copies/105 cells (p = 0.0014), patients with HIV infection – 3.84 [3.09; 4.20] log10 TTV DNA copies/105 cells (p < 0.001) and in the group of patients with severe COVID-19 infection, point 1 – 3.67 [3.09; 3.91] log10 TTV DNA copies/105 cells (p < 0.001).
About the Author
O. V. Osipkina
Gomel State Medical University
Belarus
Belarus
Olga V. Osipkina – Head of the Research Laboratory
5, Lange Str., 246000, Gomel
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