Which cells are particularly decreased in lymphopenia?
In COVID-19 patients, decreases were observed in total lymphocytes, CD4+
and CD8+ T cells, B cells and natural killer cells. T cell and natural
killer cell counts were below normal levels, while B cell counts were at
the low end of the normal range. A reduction in specific subsets of
lymphocytes, such as CD16+CD56+ natural killer cells and regulatory T
cells, was reported in severe COVID-19 patients.49