Files in this Data Supplement:

• Supplementary Material Table (Microsoft Word, 401 KB) - Consists of:
  Table 1.Calculated pK_a values for free C3d at ionic strengths corresponding to 15, 150, and 1500 mM using structure 1c3d.
  
  Table 2. Calculated pK_a values for free CR2 at ionic strengths corresponding to 15, 150, and 1500 mM using structure 1ly2.
  
  Table 3. Calculated pK_a values for C3d-CR2 complex at ionic strengths corresponding to 15, 150, and 1500 mM using structure 1ghq.