Immunomodulation in COVID-19

Immunology forms the basis for effective treatment strategies and production of vaccines. In COVID 19 immune insufficiency may increase viral replication while uncontrolled immunity may result in tissue damage. The angiotensin converting enzyme receptors on alveolar type 2 cells of lungs act as target cells are the sites of Corona virus attack. These cells through cytokines or interferons initiate an early local response which may control the infection. However, in COVID-19 this interferon response can be subdued or lagging which may allow the COVID virus to escape detection by the innate immunity or depress the downstream reaction leading to unchecked SARS-COV-2 replication. The suppression of host responses leads to increase in pro-inflammatory cytokines and the resulting inflammatory damage leads to a release of suppressive cytokines as a counter regulatory response. This is the cytokine storm. Thus, immuneregulatory treatments that may succeed are the ones that are in real time tuned to the subject's immunophenotype, where immunosuppression may be helpful at some points while immune-stimulation in others.