Hospitalized SARS-CoV-2 patients had a persistent decline
in CD4+ T cells, whereas CD8+ T cells gradually recover after one
month
To assess the longitudinal effect of COVID-19 on T cell populations, we
sampled PBMCs from patients with COVID-19 over a period of 6-8 months.
PBMCs were analyzed by flow cytometry to investigate immunophenotype
across the various T cell compartments.
The lymphocyte populations recovered, with a substantial increase in
cell counts at 1 month (P=0.0003) that remained consistent until 6-8
month (P=0.0003) (Figure 1A). Total T cells (CD3+T cells) increased
significantly after one month (P0.0001) and then dropped slightly at 6-8
months (P=0.022) but remained significantly higher than at the time of
enrolment (P=0.021) (Figure 1B) (Table 3).
When comparing CD4+T cells to enrolment, a constant and significant
reduction was observed at one month (P=0.022) and continued until 6-8
months (P=0.0016) (Figure 1C). In relation to CD8+ T cells, the increase
was significantly higher at 6 months compared to that at enrolment
(P=0.017) and at one month (P=0.012) (Figure 1D) (Table 3).
Together, these data are reflective of the alterations in the levels of
various immune cell types during COVID-19, in line with observations
made by others [5-9].