Figure 2.

OPSS-liposomes are internalized by white blood cells with CR3.

Notes: Uptake of liposomes was detected by the presence of rhodamine in the cells. Binding of complement C3 to OPSS-liposomes directs internalization into cells via CR3 (CD11b). Non-OPSS-liposomes (control) display limited internalization by cells. OPSS-liposomes and control-liposomes are not readily internalized into cells when incubated in serum depleted of complement C3 (C3−), demonstrating the necessity of the C3–OPSS complex for internalization.

Abbreviations: CR3, complement receptor 3; OPSS, orthopyridyl disulfide.