TABLE 2.

Comparison of antibodies against SOF2 and the FBD of SOF2 in rabbit and human immune serum^a

Serum	Dilution	Substrate	A650 ± SD
Rabbit anti-SOF2-	1:100	SOF2-H(38-1047)	>2.5
H(38-1047)	1:1,000	SOF2-H(38-1047)	1.767 ± 0.197
	1:100	FBD	1.634 ± 0.122
	1:1,000	FBD	0.349 ± 0.074
Human donor	1:100	SOF2-H(38-1047)	0.444 ± 0.056
(opsonizing)	1:100	FBD	−0.009 ± 0.005

^aRabbit anti-SOF2 serum and human serum (from the same donor that provided antibodies listed in Table 1) were diluted as indicated and reacted with microtiter wells coated with SOF2-H(38-1047) or FBD. The wells were washed and reacted with the appropriate peroxidase-conjugated second antiserum as indicated in Materials and Methods. Wells were done in triplicate. Wells coated with BSA and treated as described above served as blanks, and the value for these was subtracted from test values. The A₆₅₀s of wells coated with FBD were slightly lower than that for wells coated with BSA, resulting in a negative value for FBD.