Clinical Application of Antibody Immunity Against SARS-CoV-2: Comprehensive Review on Immunoassay and Immunotherapy

Abstract

The current COVID-19 global pandemic poses immense challenges to global health, largely due to the difficulty to detect infection in the early stages of the disease, as well as the current lack of effective antiviral therapy. Research and understanding of the human immune system can provide important theoretical and technical support for the clinical diagnosis and treatment of COVID-19, the clinical implementations of which include immunoassays and immunotherapy, which play a crucial role in the fight against the pandemic. This review consolidates the current scientific evidence for immunoassay, which includes multiple methods of detecting antigen and antibody against SARS-CoV-2. We compared the characteristics, advantages and disadvantages, and clinical applications of these three detection techniques. In addition to detecting viral infections, knowledge on the body’s immunity against the virus is desirable; thus, the immunotherapy-based neutralizing antibody (nAb) detection methods were discussed. We also gave a brief introduction to the new immunoassay technology such as biosensing. This was followed by an in-depth and extensive review on a variety of immunotherapy methods. It includes convalescent plasma therapy, neutralizing antibody–based treatments targeting different regions of SARS-CoV-2, immunotherapy targeted on the host cell including inhibiting the host cell receptor and cytokine storm, as well as cocktail antibodies, cross-neutralizing antibodies, and immunotherapy based on cross-reactivity between viral epitopes and autoepitopes and autoantibody. Despite the development of various immunological testing methods and antibody therapies, the current global situation of COVID-19 is still tense. We need more efficient detection methods and more reliable antibody therapies. The up-to-date knowledge on therapeutic strategies will likely help clinicians worldwide to protect patients from life-threatening viral infections.

In silico evaluation of anti SARS-CoV-2 antibodies neutralization power: A blueprint with monoclonal antibody Sotrovimab

“…Antibody-based therapies has proven its e ciency against SARS-CoV-2 virus and appears to be the most promising approach to control COVID-19 pandemic. A number of neutralizing monoclonal antibodies used in clinical setting showed very good results particularly in stopping the disease progression [26,27]. However, constant emergence of new virus' variants hinder the potency of available anti-SARS-CoV-2 antibodies and urged the continuous development of improved more effective neutralizing antibody.…”

Anti-SARS-CoV-2 Antibody Status at the Time of Hospital Admission and the Prognosis of Patients with COVID-19: A Prospective Observational Study

“…Several studies have found a positive association between antibody titres and disease severity and the probability of the risk of death in patients hospitalised with COVID-19. The authors of these studies have proposed that more severe disease stimulates more intensive antibody production [ 8 , 9 , 10 , 11 ]. This association was also apparent while measuring neutralising activity [ 9 , 11 ].…”

“…The main difference between the studies that have connected higher titres of anti-SARS-CoV-2 antibodies with severe and fatal disease [ 8 , 9 , 10 , 11 ] and later studies that identified the protective role of the early development of strong antibody response [ 5 , 6 , 7 ] is the temporal factor. The studies that identified the early antibody response as a protective factor assessed it at the early stages of the disease.…”

“…The presence of neutralising antibodies within the first weeks of the disease is also associated with earlier virus clearance and the probability of survival [ 7 ]. However, this topic remains controversial because previous studies have reported an association between high antibody titres in hospitalised patients and more severe disease [ 8 , 9 , 10 , 11 ]. Anti-S antibodies play a crucial role in recovering from COVID-19.…”

Selection of plasma donors for the production of anti-SARS-CoV-2 immunoglobulin-based therapies: Strategies for quantitative antibody measurements

“…Although initially promising, the use of COVID-19 convalescent plasma (CCP) has not been effective in preventing disease progression for the majority of patients, as observed in the studies published to date [3] , [4] . Some factors that may explain the finding of discrepant and often frustrating results between studies may be the fact that, in most protocols, patients receive CCP from only 1 or 2 donors, in addition to the differences in antibody titers and their quantification methods, and different infusion times between the study protocols [5] .…”