Patients with severe COVID-19 exhibit marked lymphopenia. This preprint by Feng et al. used immunohistochemistry and immunofluorescence to characterize hilar and subscapular lymph nodes and spleens post-mortem from six patients who died from COVID-19. In addition to splenic and lymph node atrophy and necrosis, the authors reported significant lymphocytic apoptosis. Of note, ACE2-expressing CD68+CD169+ macrophages were detected in the splenic marginal zone and in marginal sinuses of lymph nodes, and these macrophages contained SARS-CoV-2 nucleoprotein antigen and showed upregulation of IL-6. Virally infected tissues also showed higher expression of FAS. This suggests that CD169+ macrophages could contribute to viral spread, excessive inflammation and activation-induced lymphocytic cell death during SARS-CoV-2 infection.
Competing interests
The author declares no competing interests.
References
Original article
- Feng Z, et al. The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) directly decimates human spleens and lymph nodes. medRxiv. 2020 doi: 10.1101/2020.03.27.20045427. [DOI] [Google Scholar]