SIGLEC1 and HIV-1 infection: We observed a monocyte gene expression profile related to HIV-1 infection that indicated a “hybrid” monocyte with increased expression of macrophage-associated markers: monocyte chemotactic protein-1 (MCP-1, CCL2), CC-chemokine receptor 5 (CCR5), and sialoadhesin (Sn, CD169, Siglec 1) [11].