RETRACTED: Toxicity of spike fragments SARS-CoV-2 S protein for zebrafish: A tool to study its hazardous for human health?

Abstract

Despite the significant increase in the generation of SARS-CoV-2 contaminated domestic and hospital wastewater, little is known about the ecotoxicological effects of the virus or its structural components in freshwater vertebrates. In this context, this study evaluated the deleterious effects caused by SARS-CoV-2 Spike protein on the health of Danio rerio , zebrafish. We demonstrated, for the first time, that zebrafish injected with fragment 16 to 165 (rSpike), which corresponds to the N-terminal portion of the protein, presented mortalities and adverse effects on liver, kidney, ovary and brain tissues. The conserved genetic homology between zebrafish and humans might be one of the reasons for the intense toxic effects followed inflammatory reaction from the immune system of zebrafish to rSpike which provoked damage to organs in a similar pattern as happen in severe cases of COVID-19 in humans, and, resulted in 78,6% of survival rate in female adults during the first seven days. The application of spike protein in zebrafish was highly toxic that is suitable for future studies to gather valuable information about ecotoxicological impacts, as well as vaccine responses and therapeutic approaches in human medicine. Therefore, besides representing an important tool to assess the harmful effects of SARS-CoV-2 in the aquatic environment, we present the zebrafish as an animal model for translational COVID-19 research.

Zebrafish models of COVID-19

“…The efficiency of this process increased on the 14th day, conferring a reduction in the mortality rate of the immunized animals and suggesting the similarity to infected human individuals with COVID-19 (Ventura Fernandes et al. 2022 ). Antibody production was found not only in the serum, but also in the zebrafish eggs as a result of passive transfer to protect the offspring.…”

“…Recombinant SARS-CoV-2 S RBD was sufficient to cause olfactory, renal and cardiovascular pathologies in larvae and adult zebrafish (Ventura Fernandes et al. 2022 ). However, there is no evidence that this response is directly dependent on the SARS-CoV-2 Spike—zebrafish Ace2 interaction.…”

“…In addition, it was shown that rSpike injection affected the nervous system and caused significant renal and liver alterations and ovary damage in adult zebrafish (Ventura Fernandes et al. 2022 ).…”

A novel insight on SARS-CoV-2 S-derived fragments in the control of the host immunity

“…Humanized adult zebra sh infected with SARS-CoV-2 protein S in the swim bladder showed accumulation of macrophages and granulocytes 9 . Animals infected with the recombinant spike protein also showed a toxic in ammatory response with macrophage in ltrate 51 . We found a similar response.…”

The pharmaceutical industry is dangerous to health. Further proof with COVID-19

“…However, the spike protein alone (without being part of the coronavirus) is highly toxic and can damage the liver, kidney, ovaries, endothelial cells, and alter and cross the blood-brain barrier. [ 150 , 155 ] In addition, European Medicines Agency (EMA) reports indicate that mRNA can be found in many organs such as spleen, heart, kidney, lung and brain, ovaries, and testis with Pfizer’s vaccine (p. 54),[ 54 ] and in spleen, brain, heart, lung, eyes, and testis with Moderna’s vaccine (p. 47,52).…”