T-cell immunobiology and cytokine storm of COVID-19

The 2019 coronavirus illness (COVID 2019) first manifests as a newly identified pneumonia and may quickly escalate to acute respiratory distress syndrome, which has caused a global pandemic. Except for individualized supportive care, no curative therapy has been steadfastly advised for COVID-19 up until this point. T cells and virus-specific T lymphocytes are required to guard against viral infection, particularly COVID-19. Delayed immunological reconstitution (IR) and cytokine storm (CS) continue to be significant barriers to COVID-19 cure. While severe COVID-19 patients who survived the disease had considerable lymphopenia and increased neutrophils, especially in the elderly, their T cell numbers gradually recovered. Exhausted T lymphocytes and elevated levels of pro-inflammatory cytokines, including IL6, IL10, IL2, and IL17, are observed in peripheral blood and the lungs. It implies that while convalescent plasma, IL-6 blocking, mesenchymal stem cells, and corticosteroids might decrease CS, Thymosin α1 and adaptive COVID-19-specific T cells could enhance IR. There is an urgent need for more clinical research in this area throughout the world to open the door to COVID-19 treatment in the future.