The investigators hypothesize that the systemic delivery of WJ-MSCs exerts an anti-inflammatory action and anti-apoptotic effect in the lung of COVID-19, Influenza A, Metapneumovirus or RSV patients. The nature of these cells to immunomodulate both tissue resident and bloodborne immune cells towards a more anti-inflammatory and tolerogenic profile, results in a reduction of tissue-based inflammation within the lung and triggering of repair responses. This clinically culminates in a beneficial action on patients with severe respiratory complications associated with pneumonia.
To investigate the safety and tolerance of a single infusion of ProTrans® in subjects with severe respiratory complications associated with pneumonia caused by COVID-19, Influenza A, Metapneumovirus or RSV infection.