Durability of COVID-19 humoral immunity post infection and different SARS-COV-2 vaccines.

BACKGROUND: The global challenge posed by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has been a major concern for the healthcare sector in recent years. Healthcare workers have a relatively high risk of encountering COVID-19 patients, making protective immunity against SARS-CoV-2 is a priority for them. This study aims to evaluate the longitudinal measurement of SARS-CoV-2 IgG spike protein antibodies in healthcare workers (HCWs) after COVID-19 infection and after receiving the first and second doses of SARS-CoV-2 vaccines, including Pfizer-BioNTech (BNT162b2) and Oxford-AstraZeneca (AZD1222). METHODS: This longitudinal cohort study involved 311 healthcare workers working in two tertiary hospitals in Saudi Arabia. All participants were followed between July 2020 and July 2022 after completing the study questionnaire. A total of 3 ml of the blood samples were collected at four intervals: before/after vaccination. RESULTS: HCWs post-infection had lower mean SARS-CoV-2 IgG levels three months post-infection than post-vaccination. 92.2% had positive IgG levels two weeks after the first dose and reached 100% after the second dose. Over 98% had positive antibodies nine months after the second dose, regardless of vaccine type. The number of neutralizing antibodies decreased and was around 50% at nine months after the second dose. CONCLUSION: The results show different antibody patterns between infected and vaccinated HCWs. A high proportion of participants had positive antibodies after vaccination, with high levels persisting nine months after the second dose. Neutralizing antibodies decreased over time, with only about 50% of participants having positive antibodies nine months after the second dose. These results contribute to our understanding of immunity in healthcare workers and highlight the need for the continuous monitoring and possible booster strategies.

Repurposing the oncolytic virus VSV∆51M as a COVID-19 vaccine.

The coronavirus disease 2019 (COVID-19) pandemic imposes an urgent and continued need for the development of safe and cost-effective vaccines to induce preventive responses for limiting major outbreaks around the world. To combat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), we repurposed the VSV∆51M oncolytic virus platform to express the spike receptor-binding domain (RBD) antigen. In this study, we report the development and characterization of the VSV∆51M-RBD vaccine. Our findings demonstrate successful expression of the RBD gene by the VSV∆51M-RBD virus, inducing anti-RBD responses without attenuating the virus. Moreover, the VSV∆51M-RBD vaccine exhibited safety, immunogenicity, and the potential to serve as a safe and effective alternative or complementary platform to current COVID-19 vaccines.

IL-35 and IL-37 are negatively correlated with high IgE production among children with asthma in Saudi Arabia.

BACKGROUND: Asthma is one of the most prevalent inflammatory disorders among children in Saudi Arabia. OBJECTIVE: This study aimed to determine the correlation between the serum levels of vitamin D, immunoglobulin E (IgE), and cytokine (interferon-gamma (IFN-γ), interleukin (IL)-1ß, IL-4, IL-6, IL-10, IL-13, IL-35, and IL-37) in relation to the severity of disease in patients with asthma. METHODS: This case-control study was carried out at King Abdullah Specialist Children's Hospital, Saudi Arabia, and included 48 patients with asthma and 47 matched controls, aged 6-14 years. A validated questionnaire was administered to the participants, after which each patient with asthma underwent pulmonary function tests. The serum levels of vitamin D, IgE, IFN-γ, IL-1ß, IL-4, IL-6, IL-10, IL-13, IL-35, and IL-37 of each participant were also measured. RESULTS: Patients with asthma demonstrated significantly higher IgE and cytokine (IL-1ß, IL-4, IL-6, IL-10, IL-13, IL-35, and IL-37) levels compared to the control group (p value < .001). The levels of IL-1ß, IL-4, IL-10, and IL-13 were consistently positively correlated with the serum levels of IgE among patients with asthma. However, the IgE levels in patients with asthma were consistently negatively correlated with IL-35 and IL-37. CONCLUSIONS: We found significantly higher levels of eosinophils, IgE, IL-1ß, IL-4, IL-6, IL-10, IL-13, IL-35, and IL-37 in patients with asthma compared to the controls, but no relationship between vitamin D and asthma.