I. Paul^{* *}Correspondence: I. Paul, Department of Antibiotics and Microbiology, University of Victoria, Victoria BC, Canada, Email:

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Description

The organs of the immune system that defend against infections are found in the body. It is important for maintaining health and development. It also guards against harmful substances, germs, and cell abnormalities (neoplasm). White blood cells, which may circulate throughout the body via blood vessels, are an important part of the immune system. The body transfers cells and fluids between blood and lymphatic vessels and enables the lymphatic system to monitor for invading microorganisms. Lymph is carried through lymphatic vessels. Antigens might be encountered in distinct compartments within each lymph node. Immune cells and foreign parti- cles enter lymph nodes through entering lymphatic veins. They are delivered to tissues through-out the body once they enter the bloodstream. They repeat the cycle by scanning the lymphatic system for specific substances and then gradually back into it.

COVID-19 is an RNA virus. It has a diameter of 50–150 nanometers. It has a hump on one side and coasters on the other. It provides a bigger binding interface and additional ACE2 con- nections. It has a greater affinity and can make better contact with ACE2’s N-terminal helix. It spreads through coughing and sneezing droplets, enters the nasal system through inhalation, and begins multiplying. The COVID-19 virus major receptor is ACE2. The immune system is the best defense against COVID-19 because it supports the body’s natural ability to defend against pathogens (e.g., viruses, bacteria, fungus, protozoa, and worms) and resist infections. COVID-19 infections remain undetectable as long as the immune system is functioning prop-erly. Innate immunity (quick response), adaptive immunity (delayed response), and passive immunity are the three forms of immunity. Natural immunity, which comes from the mother, and artificial immunity, which comes from medicine, are the two types of passive immunity.

Researchers are working to strengthen the immune system’s response to COVID-19, and that was one of the outcomes. The COVID-19 genome encodes ten proteins, one of which is the S protein, as described, because a glycoprotein is present in the virus-infected area. The S protein is a key therapeutic target, and antibodies can be used to target it. Immunization of animals with S protein-oriented vaccines results in the production of neutralizing antibodies, which is particularly successful in avoiding infection by homologous coronavirus. When human cells are infected with virus entities, epitopes from any of the viruses’ proteins can theoretically be bound and presented by MHC-1 receptors on host cell surfaces, causing CD4 and CD8 T cells to be stimulated, resulting in antibody-mediated and cell-mediated immune responses.

Transfusion of convalescent plasma has been utilized to treat infections caused by other human like SARS-CoV and MERS-CoV. It has also been proven to be effective and safe for human use. Due to the presence of neutralizing and non-neutralizing antibodies, convalescent plasma has antiviral properties, but it also has immune modulatory properties through signaling path-ways involving anti-inflammatory cytokines, complement blocking antibodies, autoantibodies, anti- idiotype antibodies, and factors involved in hemostasis, depending on the doses used.

In numerous viral infections, neutralizing antibodies (NAbs) are frequently linked to long-term protection. Understanding the presence of NAbs in SARS-CoV-2 infection could therefore be beneficial. Because the start and synthesis of NAbs appear to be similar in children and adults, the majority of them produce varying levels of neutralizing antibodies. The speculative research was shown NAbs produced during the acute phase may not be sufficient for viral clearance, which could lead to persistent viral dissemination.