Dados do Trabalho

Título

Investigation of the Nucleocapsid protein of the SARS-CoV-2 encoding gene as a target for diagnosis and genetic variability during COVID-19 2021 and 2022 waves

Introdução

The control of the pandemic caused by the novel betacoronavirus responsible for Severe Acute Respiratory Syndrome (SARS-CoV-2) is based on vaccination and reduction of virus circulation through social distancing and transmission-blocking post-diagnosis. Unlike other infectious diseases where vaccines prevent transmission of the infectious agent, in the case of SARS-CoV-2, available vaccines and natural infection result in decreased morbidity, reducing hospitalizations and deaths, but do not prevent its transmission. Therefore, monitoring of virus circulation is primordial, and genetic evolutive conserved encoding genes are the target of choice to detect SARS-CoV-2 new infections.  The nucleocapsid (N) protein of SARS-CoV-2 is present and conserved among CoVs, being essential for viral cycle functions and highly antigenic, consisting in a promising molecule for diagnostics and the development of new vaccines. Research approved by the Ethics Committee: Human Research Committee of UFABC (CAAE 39420920.1.0000.0082)

Objetivo (s)

To investigate the genetic variability of the N protein of SARS-CoV-2 encoding gene and its efficacy as a target for the virus diagnosis. 

Material e Métodos

1700 positive samples for SARS-CoV-2 were obtained through RT-qPCR diagnosis, using the Allplex™ 2019-nCoV Assay kit. The source of biological material was saliva, self-collected by the patients themselves using a kit developed by our team. Subsequently, the samples were subjected to complementary DNA (cDNA) synthesis, using the reverse transcriptase (RT) Script® enzyme (Cellco Biotec). The quality of the cDNA was confirmed by amplification of a 404 bp fragment corresponding to the human mitochondrial variation region encoding sequence 1 (HV1). The same cDNA samples were used for amplification of the gene encoding the N protein (1250 bp), with results elucidated through 1.5% agarose gel electrophoresis. All DNA fragments obtained were sent for sequencing by Sanger’s method.

Resultados e Conclusão

All samples underwent cDNA quality testing by amplification of HV1 404 bp fragment. The gene encoding the N protein from SARS-CoV-2 was amplified from samples with a CT lower than 32 and samples of all COVID-19 waves occurred in 2021 and 2022. Genetic variability evaluation of the SARS-Cov-2 N-protein encoding gene is underway.

Palavras Chave

SARS-CoV-2; Sequencing; Betacoronavirus; vaccination; Pandemic.