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Introduction: SARS-CoV-2 vaccines production and distribution enabled the return to normalcy worldwide, but it was not fast enough to avoid the emergence of variants capable of evading immune response induced by prior infections and vaccination. This study evaluated, against Omicron sublineages BA.1, BA.5 and BQ.1.1, the antibody response of a cohort vaccinated with a two doses CoronaVac protocol and followed by two heterologous booster doses. Methods: To assess vaccination effectiveness, serum samples were collected from 160 individuals, in 3 different time points (9, 12 and 18 months after CoronaVac protocol). For each time point, individuals were divided into 3 subgroups, based on the number of additional doses received (No booster, 1 booster and 2 boosters), and a viral microneutralization assay was performed to evaluate neutralization titers and seroconvertion rate. Results: The findings presented here show that, despite the first booster, at 9m time point, improved neutralization level against omicron ancestor BA.1 (133.1 to 663.3), this trend was significantly lower for BQ.1.1 and BA.5 (132.4 to 199.1, 63.2 to 100.2, respectively). However, at 18m time point, the administration of a second booster dose considerably improved the antibody neutralization, and this was observed not only against BA.1 (2361.5), but also against subvariants BQ.1.1 (726.1) and BA.5 (659.1). Additionally, our data showed that, after first booster, seroconvertion rate for BA.5 decayed over time (93.3% at 12m to 68.4% at 18m), but after the second booster, seroconvertion was completely recovered (95% at 18m). Discussion: Our study reinforces the concerns about immunity evasion of the SARS-CoV-2 omicron subvariants, where BA.5 and BQ.1.1 were less neutralized by vaccine induced antibodies than BA.1. On the other hand, the administration of a second booster significantly enhanced antibody neutralization capacity against these subvariants. It is likely that, as new SARS-CoV-2 subvariants continue to emerge, additional immunizations will be needed over time.
Assuntos
Vacina BNT162 , Vacinas contra COVID-19 , Vacinas de Produtos Inativados , Humanos , Anticorpos Antivirais , Imunização , SARS-CoV-2 , Anticorpos NeutralizantesRESUMO
Background: The emergence of the new SARS-CoV-2 Omicron variant, which is known to have a large number of mutations when compared to other variants, brought to light the concern about vaccine escape, especially from the neutralization by antibodies induced by vaccination. Methods: Based on viral microneutralization assays, we evaluated in 90 individuals the impact on antibody neutralization induction, against Omicron variant, by a booster dose of BNT162b2 mRNA vaccine after the CoronaVac primary vaccination scheme. Results: Here we show that the percentage of seroconverted individuals 30 and 60 days after CoronaVac scheme was 16.6% and 10%, respectively. After booster dose administration, the seroconvertion rate increased to 76.6%. The neutralization mean titer against Omicron in the CoronaVac protocol decreased over time, but after the booster dose, the mean titer increased 43.1 times. Conclusions: These results indicate a positive impact of this vaccine combination in the serological immune response against SARS-CoV-2 Omicron variant.
RESUMO
The emergence of the new SARS-CoV-2 Omicron variant, which is known to accumulate a huge number of mutations when compared to other variants, brought to light the concern about vaccine escape, especially from the neutralization by antibodies induced by vaccination. In this scenario, we evaluated the impact on antibody neutralization induction, against Omicron variant, by a booster dose of BNT162b2 mRNA vaccine after the CoronaVac primary vaccination scheme. The percentage of seroconverted individuals 30 and 60 days after CoronaVac scheme was 17% and 10%, respectively. After booster dose administration, the seroconvertion rate increased to 76.6%. The neutralization mean titer against Omicron in the CoronaVac protocol decreased over time, but after the booster dose, the mean titer increased 43.1 times, indicating a positive impact of this vaccine combination in the serological immune response.
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Colorectal cancer (CRC) is a public health concern and the second most common type of cancer among men and women causing a significant mortality. Biomarkers closely linked to the disease morbidity could holds potential as diagnostic and/or prognostic biomarker for the disease. This review provides an overview of recent advances in the search for colorectal cancer biomarkers through genomics and proteomics according to clinical function and application. Specifically, a number of biomarkers were identified and discussed. Emphasis was placed on their clinical applications relative to the diagnosis and prognosis of CRC. The discovery of more sensitive and specific markers for CRC is an urgent need, and the study of molecular targets is extremely important in this process, as they will allow for a better understanding of colorectal carcinogenesis, identification and validation of potential genetic signatures.
