Figure 3.

CD20+ B cell loss in a COVID-19 deceased patient (age 79 years) as compared to a control patient (age 78 years). (A) Histopathology of cell-rich areas in the bone marrow show immaturity of myelopoiesis (left row), severe loss of CD20+ B cells (middle row), and a stabilized CD3+ T cell count (right row) in the COVID-19 patient as compared to the control patient. (B) Histopathology of the spleen shows atrophy of peri-arteriolar white pulp (left row), caused by loss of CD20+ B cells (middle row); the peri-arteriolar CD3+ T cell distribution is regular (right row).

Abbreviations: HPF, high power field; H&E, haematoxylin and eosin; BM, bone marrow; SPL, spleen.