Fig. 6. Glycosylation pattern of CD11b expressed on T cells.

a Western blot of CD11b on T cell lysates treated with PNGase F, O-glycosidases or Neuraminidase A for 4 h as indicated. b Lectin blot analysis of purified CD11b-flag from transduced human CD3⁺ T cells. Complete membrane blots are included in Supplementary Fig. 18. a, b One representative western blot from n = 2 biologically independent experiments. c Model of the interaction between Siglec-15 present on the surface of interacting cells and CD11b/CD18 integrin from the cell surface of T cells. The full extracellular domain of Siglec-15 (cyan) was manually built using the crystal structure of the V-set domain and the C2-type Ig-like domain of CD22 (PDB ID:5VKJ). The full extracellular domain of CD11b (blue)/CD18 (wheat) (PDB ID 7USM)⁷³ heterodimer (from the cell surface of T cells) is represented. The I domain (taken from PDB ID 3K72) and the thigh region of CD11b are colored in gray and pink, respectively. The N-linked glycans present in CD11b are represented as blue spheres. In this model, Siglec-15 binding pocket at V domain is interacting with the sialylated N692-linked glycan of CD11b.