RESUMO
There is still a need for safe, efficient and low-cost coronavirus disease 2019 (COVID-19) vaccines that can stop transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here we evaluated a vaccine candidate based on a live recombinant Newcastle disease virus (NDV) that expresses a stable version of the spike protein in infected cells as well as on the surface of the viral particle (AVX/COVID-12-HEXAPRO, also known as NDV-HXP-S). This vaccine candidate can be grown in embryonated eggs at low cost similar to influenza virus vaccines and it can also be administered intranasally, potentially to induce mucosal immunity. We evaluated this vaccine candidate in prime-boost regimens via intramuscular, intranasal, or intranasal followed by intramuscular routes in an open label non-randomized non-placebo-controlled phase I clinical trial in Mexico in 91 volunteers. The primary objective of the trial was to assess vaccine safety and the secondary objective was to determine the immunogenicity of the different vaccine regimens. In the interim analysis reported here, the vaccine was found to be safe and the higher doses tested were found to be immunogenic when given intramuscularly or intranasally followed by intramuscular administration, providing the basis for further clinical development of the vaccine candidate. The study is registered under ClinicalTrials.gov identifier NCT04871737. Funding was provided by Avimex and CONACYT.
RESUMO
Current medical guidelines consider COVID-19 pregnant women a high-risk group. Physiological gestation down regulates the immunological response to maintain "maternal-fetal tolerance"; hence, a SARS-CoV-2 infection constitutes a potentially threatening condition to both the mother and the fetus. To establish the immune profile in pregnant COVID-19+ patients a cross-sectional study was conducted. Leukocyte immunophenotype, mononuclear leukocyte response to polyclonal stimulus and cytokine/chemokine serum concentration were analyzed in pregnant fifteen COVID-19+ and control groups (fifteen non-pregnant COVID-19+, and thirteen pregnant COVID-19-women). Pregnant COVID-19+ patients exhibit lower percentages of monocytes HLA-DR+ compared with control groups. Nevertheless, pregnant COVID-19+ women show a higher percentage of monocytes CD39+ than controls. Furthermore, a higher concentration of TNF-, IL-6, MIP1b and IL-4 was observed within the pregnant COVID-19+ group. Our result shows that pregnant women express immunological characteristics that potentially mediate the immune response in COVID-19.
RESUMO
Within the last 30 years 3 coronaviruses, SARS-CoV, MERS-CoV and SARS-CoV-2, have evolved and adapted to cause disease and spread amongst the human population. From the three, SARS-CoV-2 has spread world-wide and to July 2020 it has been responsible for more than 11 million confirmed cases and over half a million deaths. In the absence of an effective treatment or vaccine, social distancing has been the most effective measure to control the pandemic. However it has become evident that as the virus spreads the only tool that will allow us to fully control it is an effective vaccine. There are currently more than 150 vaccine candidates in different stages of development using a variety of viral antigens, with the S protein being the most targeted antigen. Although some new experimental evidence suggests cross-reacting responses between coronaviruses are present in the population, it remains unknown whether potential shared antigens between different coronaviruses could provide cross-protection. Given that coronaviruses are emerging pathogens and continue to represent a threat to global health, the development of a SARS-Cov-2 vaccine that could provide universal protection against other coronaviruses should be pushed forward. Here we present a thorough review of reported B and T cell epitopes shared between SARS-CoV-2 and other relevant coronaviruses, in addition we used web-based tools to predict novel B and T cell epitopes that have not been reported before. Analysis of experimental evidence that is constantly emerging complemented with the findings of this study allow us support the hypothesis that cross-reactive responses, particularly those coming from T cells, might play a key role in controlling infection by SARS-CoV-2. We hope that with the evidence presented in this manuscript we provide arguments to encourage the study of cross-reactive responses in order to elucidate their role in immunity to SARS-CoV-2. Finally we expect our findings will aid targeted analysis of antigen-specific immune responses and guide future vaccine design aiming to develop a cross reactive effective vaccine against respiratory diseases caused by coronaviruses.
RESUMO
On January 30th, 2020, the WHO declared the outbreak of COVID19, a disease due to the new coronavirus called SARS-CoV-2. Certain comorbidities, symptoms and signs are characteristic of COVID19 in the general population and in pregnant women. However, pregnant women are considered as a high-risk group for COVID19. To know about the frequency of comorbidities, signs and symptoms, the presence of lymphopenia, antibodies response to SARS-CoV2 and cytokine and chemokine serum concentration, six pregnant women with COVID19 were studied at the moment of admission. The lower concentration of CCL17 was detected in the Pregnant COVID19 group, similar concentration of IL-6 was also detected in non-pregnant and pregnant COVID19 patients. Our result show that pregnant and non-pregnant women with COVID19 has similar cytokine profile.
