Figure 4. Immunofluorescent microscopy of rCR2 or anti-C3d bound to C3d⁺ red blood cells.

Sensitised sheep red blood cells were incubated with either human (panels a, b, c and d) or rat (panels e and f) C6 deficient serum to generate C3d plasma membrane deposition in the absence of cell lysis. Cells were then incubated with either anti-human C3d followed by mouse anti-human-FITC secondary (panel b) or secondary antibody only (panel a). C3d⁺ cells were also incubated with rCR2 followed by secondary anti-HIS-FITC (panel d and f) or secondary alone (panel c and e).