ITIH4 and HIV-1 infection: Foremost, the amount, complexity and variability of the glycan shield that decorates the surface of gp120 most likely influences the ability of XCL1 to block HIV-1 infection, since nearly half the molecular mass of gp120 is comprised of N-linked and O-linked glycans, and changes to these carbohydrate moieties result in altered neutralization sensitivity [31]–[36].