Table 2.

The influence of AP and CP activation on the nature of the deposited C3 fragments and on MAC formation (mean ± SD)

	Total C3 deposition* (n = 10)	C3b/iC3b deposition† (n = 5)	MAC formation‡ (n = 8)
Response in NHS
Alone	100	100	100
+ anti-FD	105 ± 32.3	47.6 ± 12.1	13.6 ± 6.5
+ Mg/EGTA	117 ± 52.1	165 ± 24.1	200 ± 66.0
+ anti-FD +	6.0 ± 3.9	0	6.5 ± 5.6
Mg/EGTA
+ EDTA	1.8 ± 3.7	0.5 ± 0.3	2.4 ± 6.9

^*Probing with FITC-rabbit anti-human C3d.

^†Probing with FITC-rabbit anti-human C3c.

^‡Probing with FITC-E11.

Human PBMC from healthy donors were isolated and incubated in 30% v/v autologous serum, with or without 20 mm EGTA/4.4 mm MgCl₂ (Mg/EGTA), 20 mm EDTA (EDTA) and 5 μg/ml rabbit anti-human factor D (anti-FD) as described in Table 1. Complement activation was measured as the difference in mean Fl1 signal (net MFI) between cells incubated in NHS under the various conditions, and cells incubated in VBS alone, and expressed as a percentage of the signal obtained in NHS alone. The results are given as means ± 1 SD.