It is found in especially high amounts on macrophages of the spleen, liver, lymph node, bone marrow, colon, and lungs.

Soluble SIGLEC-1 is a biomarker of monocyte-macrophage activation in systemic lupus erythematosus (SLE) and other autoimmune disorders.

[2] In patients with rheumatoid arthritis, the protein has been found in great amounts on macrophages of the affected tissues.

During this binding process a salt bridge (protein) is formed between a highly conserved arginine residue (from the v-set domain to the 3'-sialyllactose) and the carboxylate group of the sialic acid.

Research using a murine melanoma model has demonstrated that these subcapsular sinus macrophages bind to sialylated proteins present on the surface of pioneer metastatic cells shortly after their landing in the lymph nodes.