Figure 1Evaluation of recombinant early secretory antigenic target 6 (rESAT-6) gene as polymerase chain reaction product. Lanes 4 and 5 = rESAT-6 gene.
Figure 2Electrophoresis of recombinant plasmid after digestion by restriction endonucleases.
Figure 3Purification of recombinant early secretory antigenic target 6 (rESAT-6) protein as determined by sodium dodecyl sulfate–polyacrylamide gel electrophoresis.
Figure 4Skin test reaction results: (A) Sensitized to Mycobacterium avium; (B) sensitized to bacillus Calmette–Guérin; (C) sensitized to Mycobacterium tuberculosis; and (D) sensitized to phosphate-buffered saline. PPD = tuberculin purified protein derivative; rESAT-6 = recombinant early secretory antigenic target 6.
Table 1Potency test.
Guinea pigs |
(Standard) PPD
|
(Test) ESAT-6
|
1 |
2 |
3 |
4 |
5 |
6 |
No |
1/100 |
1/500 |
1/2500 |
1/100 |
1/500 |
1/2500 |
830 |
22 |
20.5 |
17 |
24 |
20.8 |
16 |
831 |
18.5 |
18 |
15 |
19 |
18.2 |
14.5 |
832 |
27 |
24.5 |
16.5 |
27.5 |
23.2 |
14 |
838 |
26.5 |
23 |
17 |
27.2 |
23 |
14.5 |
839 |
25.5 |
24.5 |
17.5 |
26.2 |
24.2 |
15.5 |
840 |
25.5 |
24 |
20 |
26.8 |
24.8 |
19.5 |
841 |
25 |
23.5 |
20 |
26.7 |
24 |
9.5 |
842 |
23.5 |
21 |
19 |
24.8 |
22.1 |
18 |
843 |
24 |
21 |
19.5 |
24.8 |
23 |
18 |
Total |
217.5 |
200 |
161.5 |
227 |
203.3 |
139.5 |
Mean |
24.17 |
22.23 |
17.94 |
25.22 |
22.58 |
15.5 |
|
Total for standard = 579 |
Total for test = 569.8 |
Table 2Skin test reaction to rESAT-6 and PPD in sensitized guinea pigs (measured in millimeter).
Groups |
Buffer
|
BCG
|
Mycobacterium tuberculosis strains
|
D4
|
PN
|
DT
|
C
|
C, DT, PN
|
N = 4 |
N = 4 |
N = 4 |
N = 4 |
N = 4 |
N = 4 |
N = 4 |
5 TU PPD |
— |
12.67 |
13.83 |
16.32 |
15.96 |
16.20 |
16.37 |
25 TU PPD |
— |
14.67 |
16.33 |
21 |
20.90 |
21.07 |
21.5 |
125 TU PPD |
— |
16.33 |
18.16 |
22.90 |
23 |
23.2 |
23.5 |
0·1 rESAT-6 |
— |
— |
— |
14 |
14.02 |
13 |
14.75 |
1 mg rESAT-6 |
— |
— |
— |
18.11 |
18.5 |
18.80 |
18.63 |
10 mg rESAT-6 |
— |
— |
— |
20.90 |
20.53 |
20.68 |
21 |