Inducible Bronchus-Associated Lymphoid Tissue in SARS-CoV-2 Infected Rhesus Macaques

Pulmonary immunity against SARS-CoV-2 infection has not been well studied. This study investigated the distribution of immune cells int the lungs of 8 rhesus macaques experimentally infected with SARS-CoV-2, and euthanized 11-14 days later. Using immunohistochemistry, inducible bronchus-associated lymphoid tissue was found in all animals. The inducible bronchus-associated lymphoid tissues were composed of B cells, T cells, and follicular dendritic cells with evidence of lymphocyte priming and differentiation. This suggests local immunity plays an important role in the SARS-CoV-2 infection. Further study of local immunity in the lung would benefit our understanding of SARS-CoV-2 pathogenesis and could lead to new interventions to control the SARS-CoV-2 infection and disease.