Recent developments in SARS-CoV-2 vaccines: A systematic review of the current studies.

Designing and manufacturing efficient vaccines against coronavirus disease 2019 (COVID-19) is a major objective. In this systematic review, we aimed to evaluate the most important vaccines under construction worldwide, their efficiencies and clinical results in healthy individuals and in those with specific underlying diseases. We conducted a comprehensive search in PubMed, Scopus, EMBASE, and Web of Sciences by 1 December 2021 to identify published research studies. The inclusion criteria were publications that evaluated the immune responses and safety of COVID-19 vaccines in healthy individuals and in those with pre-existing diseases. We also searched the VAERS database to estimate the incidence of adverse events of special interest (AESI) post COVID-19 vaccination. Almost all investigated vaccines were well tolerated and developed good levels of both humoural and cellular responses. A protective and efficient humoural immune response develops after the second or third dose of vaccine and a longer interval (about 28 days) between the first and second injections of vaccine could induce higher antibody responses. The vaccines were less immunogenic in immunocompromised patients, particularly those with haematological malignancies. In addition, we found that venous and arterial thrombotic events, Bell's palsy, and myocarditis/pericarditis were the most common AESI. The results showed the potency of the SARS-CoV-2 vaccines to protect subjects against disease. The provision of further effective and safe vaccines is necessary in order to reach a high coverage of immunisation programs across the globe and to provide protection against infection itself.

Cerebral microvascular complications associated with SARS-CoV-2 infection: How did it occur and how should it be treated?

Cerebral microvascular disease has been reported as a central feature of the neurological disorders in patients with SARS-CoV-2 infection that may be associated with an increased risk of ischemic stroke. The main pathomechanism in the development of cerebrovascular injury due to SARS-CoV-2 infection can be a consequence of endothelial cell dysfunction as a structural part of the blood-brain barrier (BBB), which may be accompanied by increased inflammatory response and thrombocytopenia along with blood coagulation disorders. In this review, we described the properties of the BBB, the neurotropism behavior of SARS-CoV-2, and the possible mechanisms of damage to the CNS microvascular upon SARS-CoV-2 infection.

Serological and Molecular Tests for COVID-19: a recent update.

The COVID-19 pandemic is probably the most devastating worldwide challenge in recent century. COVID-19 leads to a mild to severe respiratory disease and affects different organs and has become a global concern since December 2019. Meanwhile, molecular biology and diagnostic laboratories played an essential role in diagnosis of the disease by introducing serological and molecular tests. Molecular-based techniques are reliable detection tools for SARS-CoV-2 and used for diagnosis of patients especially in the early stage of the disease. While, serological assays are considered as additional tools to verify the asymptomatic infections, tracing previous contacts of individuals, vaccine efficacy, and study the seroprevalance. The average time of the appearance of anti-SARS-CoV-2 antibodies in the patient's serum is 3-6 days after the onset of symptoms for both IgM and IgA and 10-18 days for IgG. Following the outbreak of COVID-19, FDA has approved and authorized a series of serological laboratory tests for early diagnosis. Serological assays have low-cost and provide fast results but have poor sensitivity in the early stage of the viral infection. Although the serological tests may not play an important role in the active case of COVID-19, it could be effective to determine the immunity of health care workers, and confirm late COVID-19 cases during the outbreak. In this review, we compared various laboratory diagnostic assays for COVID-19.

The immune system as a target for therapy of SARS-CoV-2: A systematic review of the current immunotherapies for COVID-19.

AIMS: The immune response is essential for the control and resolution of viral infections. Following the outbreak of novel coronavirus disease (COVID-19), several immunotherapies were applied to modulate the immune responses of the affected patients. In this review, we aimed to describe the role of the immune system in response to COVID-19. We also provide a systematic review to collate and describe all published reports of the using immunotherapies, including convalescent plasma therapy, monoclonal antibodies, cytokine therapy, mesenchymal stem cell therapy, and intravenous immunoglobulin and their important outcomes in COVID-19 patients. MATERIAL AND METHODS: A thorough search strategy was applied to identify published research trials in PubMed, Scopus, Medline, and EMBASE from Dec 1, 2019, to May 4, 2020, for studies reporting clinical outcomes of COVID-19 patients treated with immunotherapies along with other standard cares. KEY FINDINGS: From an initial screen of 80 identified studies, 24 studies provided clinical outcome data on the use of immunotherapies for the treatment of COVID-19 patients, including convalescent plasma therapy (33 patients), monoclonal antibodies (55 patients), interferon (31 patients), mesenchymal stem cell therapy (8 patient), and immunoglobulin (63 patients). Except for nine severe patients who died after treatment, most patients were recovered from COVID-19 with improved clinical symptoms and laboratory assessment. SIGNIFICANCE: Based on the available evidence, it seems that treatment with immunotherapy along with other standard cares could be an effective and safe approach to modulate the immune system and improvement of clinical outcomes.