The most highly abundant proteins in CD71+ EVs from patients included proteins involved in oxygen transport [Hemoglobin subunit alpha, beta and delta (HBA1, HBB, HBD)] and acute phase response to infection [Serum amyloid A-1 protein (SAA1), major acute phase protein] with 4 to 6-fold increase compared to HD EVs. Here, SAA1 is linked to infection.