Fig. 4.

HERV-W ENV protein expression in the leukocytes of COVID-19 patients was associated with disease severity.

The COVID-19 patients have been stratified based on clinical status as asymptomatic and pauci-symptomatic (AS/PS, n = 15), mild, moderate and severe (Mild/Mod/Sev, n = 15).The percentage of HERV-W ENV-positive cells has been analysed in leukocytes, lymphocytes, monocytes, granulocytes and in T cell, B cell and NK lymphocyte subtypes. IL-6 plasma concentration was also evaluated. Data are represented as box plots (white box: healthy donors, HD; gray box: all patients positive for SARS-CoV-2). Non-parametric Kruskall Wallis test and Bonferroni's correction was used to compare groups (Table 4).