In-hospital mortality during the wild-type, alpha, delta, and omicron SARS-CoV-2 waves: a multinational cohort study in the EuCARE project.

Background: Investigating outcomes of hospitalised COVID-19 patients throughout the pandemic is crucial to understand the impact of different SARS-CoV-2 variants. We compared 28-day in-hospital mortality of Wild-type, Alpha, Delta, and Omicron variant infections. Whether the difference in risk by variant varied by age was also evaluated.

The human platelet antigen-1b (Pro) variant of αβ allosterically shifts the dynamic conformational equilibrium of this integrin toward the active state.

Integrins are heterodimeric cell-adhesion receptors comprising α and β subunits that transmit signals allosterically in both directions across the membrane by binding to intra- and extracellular components. The human platelet antigen-1 (HPA-1) polymorphism in αβ arises from a Leu → Pro exchange at residue 33 in the genu of the β subunit, resulting in Leu (HPA-1a) or Pro (HPA-1b) isoforms. Although clinical investigations have provided conflicting results, some studies have suggested that Pro platelets exhibit increased thrombogenicity.