. 2001 May;69(5):2943–2949. doi: 10.1128/IAI.69.5.2943-2949.2001

TABLE 3.

Spa and M type-specific antibodies in human serum, as determined by ELISA

Serum^a	Antibody level^b
Serum^a	Spa	M1	M2	M3	M5	M6	M12	M18	M19
1			+++				+
2	+						+
3					+++		+
4		+
5
6	+	+		+++	++++		+	+++
7	+++				+++		+
8	+			++		+++	+
9	++++		+	++			+	+
10							++
11					++++
12	++++
13	+	++++		++			+++
14					+++
15	+	++
16									+
17	++
18
19	++++
20		+++						++

The sera of 20 patients with a history of acute rheumatic fever were tested by ELISA for the presence of antibodies against rSpa and recombinant N-terminal fragments of M proteins.

Scored on the basis of absorbance at 450 nm as + (>0.2≤0.4), ++ (>0.4≤0.7), +++ (>0.7≤1.0), and ++++ (>1.0). None of the sera reacted with M24.