Passive Immunity for Coronavirus Disease 2019: A Commentary on Therapeutic Aspects Including Convalescent Plasma

Area of Science:

• Immunology and Virology
• Infectious Diseases

Background:

• The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19 in a population with naive immunity, leading to severe illness and mortality.
• Current treatments, including antivirals and anti-inflammatories, have limited efficacy, highlighting the need for immunological interventions.
• Understanding innate immune responses to SARS-CoV-2 is crucial for developing effective therapies.

Purpose of the Study:

• To review the immune responses observed in COVID-19 patients.
• To explore the application of passive immunity, drawing parallels with severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS).
• To discuss factors influencing treatment responses and the ongoing challenge of vaccine development.

Main Methods:

• Review of immune responses in COVID-19 patients, including immunoglobulin M (IgM), immunoglobulin G (IgG), and neutralizing antibodies.
• Analysis of passive immunity strategies, specifically convalescent plasma therapy.
• Comparative review of immune responses and treatment outcomes with those from SARS and MERS.

Main Results:

• Convalescent plasma from recovered COVID-19 patients, containing high titers of neutralizing antibodies, has demonstrated success in treating patients.
• The immune response involves a sequential appearance of IgM, followed by IgG and neutralizing antibodies.
• Factors influencing treatment responses are examined in comparison to SARS and MERS.

Conclusions:

• Passive immunity, particularly convalescent plasma, represents a significant therapeutic strategy for managing severe COVID-19.
• Further research into immune mechanisms and comparative analysis with SARS and MERS provides valuable insights.
• The development of effective vaccines against SARS-CoV-2, SARS-CoV, and MERS-CoV remains a critical ongoing challenge.