Sperm DNA fragmentation in men vaccinated with Gam-COVID-Vac (Sputnik V)

Abstract

Aim. To perform comparative analysis of sperm characteristics and DNA fragmentation in men vaccinated with GamCOVID-Vac (Sputnik V) and unvaccinated men.Materials and methods. Characteristics ofsemen analysis and DNA fragmentation index in ejaculate samples of 122 men, 28 of whom were vaccinated with Gam-COVID-Vac (Sputnik V), were analyzed. Study participants did not have history of coronavirus infection COVID-19. Vaccinated patients were divided into 2 groups: group 1 (n = 10) included patients for whom the time between full vaccination (2 doses of the vaccine) and ejaculate sampling was shorter than 75 days; and the group 2 (n = 18) included patients for whom the time between vaccination and ejaculate sampling was longer than 75 days. Unvaccinated men comprised the control group (group 3, n = 94). Standard semen analysis was performed in accordance with the accepted laboratory guidelines of the World Health Organization (2010). DNA fragmentation was evaluated using fluorescent labelling of single- and double-strand DNA breaks (TUNEL).Results. Totalsperm countin the group 1 was 265 ± 75 million, in the group 2 – 355 ± 67 million, in the group 3 – 304 ± 26 million. Progressive motile (PR)sperm in the group 1was 18.5 ± 1.9 %, in the group 2 – 23.2 ± 3.0 %, in the group 3 – 18.2 ± 1.1 %. Normal sperm morphology in the group 1 was 4.0 ± 0.5 %, in the group 2 – 5.8 ± 0.9 %, in the group 3 – 4.1 ± 0.3 %. The best ejaculate quality was observed in patients of the group 2, however, no statistically significant differences in semen analysis characteristics between the groups were found. Percentage of sperm with fragmented DNA (DNA fragmentation index, DFI) in the group 1 varied between 4.6 and 31.4 %, in the group 2 between 0.8 and 36.5 %, in the group 3 (control) between 1.3 and 39.8 %. Mean number of germ cells with DNA breaksin the group 1 (12.5 ± 2.4 %) was higher than in the group 2 (10.9 ± 2.0 %) and control group (10.5 ± 0.7 %), but with no statistical significance. Percentage of patients with DNA fragmentation index above the reference value (≤15 %) in the groups 1, 2 and 3 was 20, 22 and 18 % respectively. In 3 of 6 patients with increased DFI in the groups 1 and 2, this value was above the reference level even before vaccination.Conclusion. No significant effect of vaccination with Sputnik V on sperm DNA fragmentation level in men was observed.