Functional Reprogramming of Peripheral Eosinophils in Lentivirus-Infected Rhesus Macaques.

As innate immune cells, granulocytic eosinophils form part of the first line of defense against pathogens. While recent studies indicate that granulocytes have additional functions including anti-inflammatory roles, tissue homeostasis maintenance, remodeling, and trained innate immune memory, they remain understudied in viral infections, specifically in human immunodeficiency virus (HIV) infection. Using a rhesus macaque model of simian-human immunodeficiency virus (SHIV) infection, we evaluated the functional responses of peripheral granulocytes using a newly developed whole blood intracellular cytokine staining assay. We observed elevated secretion of interleukin 8 and reduced secretion of tumor necrosis factor α in peripheral eosinophils from SHIV-infected animals stimulated with lipopolysaccharide compared to experimentally naive animals. Our data suggest potential functional skewing of peripheral eosinophils towards an enhanced effector response against secondary stimuli, warranting further investigation into the mechanistic understanding of granulocyte functions to inform developing HIV therapeutics.