GlycoRNA-L and glycoRNA-S mediate human monocyte adhesion via binding to Siglec-5

It was recently reported that RNAs can be glycosylated, and a majority of such glycosylated RNAs (referred to as glycoRNAs) are located on the outer cell surface. We here reported that there are two forms of glycoRNAs, named as glycoRNA-L and glycoRNA-S, robustly expressed in human monocytes. Both of glycoRNA-L and glycoRNA-S contributed to the interaction of human monocytes and endothelial cells via directly binding to Siglec-5. GlycoRNA-L predominantly expressed in most of tissues and cell lines. GlycoRNA-S only expressed in some cell lines and tissues. Siglec-5 preferentially binds to glycoRNA-L than glycoRNA-S. The composition of glycan chains in glycoRNA-L and glycoRNA-S is different. GlycoRNA-L contains more sialic acid, whereas glycoRNA-S contains more GlcNAc. Together, these results demonstrate that two forms of glycoRNAs exist, which may play significant role in controlling the interaction of human monocytes and endothelial cells and contribute to the pathogenesis of inflammatory diseases.