Table 2.

Performance of potentially M. leprae-specific peptides (≥5 of 15 amino acid mismatches with the equivalent M. tuberculosis sequences) in IFN-γ assay as described in Materials and Methodsa

PeptideSpecificitybSensitivityc
PatientsContacts
P89751003953
Q9021954764
S9048952655
I9070904546
R9022903329
D8957903246
E8990902429
E8980901921
I9063854238
K8941851932
S9062752945
D8963753246
Q9008704259
S9047453752
K8948452129
  • a The numbers of tuberculoid leprosy patients and leprosy contacts tested varied according to the peptide used and are indicated by the peptide prefix as follows: D, 31 and 26; E, 21 and 24; I, 31 and 26; K, 42 and 41; P, 18 and 17; Q, 45 and 39; R, 21 and 17; and S, 38 and 29, respectively. Twenty United Kingdom controls were tested with each peptide.

  • b Percentage of United Kingdom donors who were nonresponders to the peptides.

  • c Percentage of TT/BT leprosy patients or staff contacts of leprosy patients who made a positive response (≥50 pg of IFN-γ/ml) to the peptides. The responses of the TT/BT leprosy patients and contacts were measured in Nepal, Ethiopia, Brazil, and Pakistan. Differences between the sensitivities obtained for the tuberculoid leprosy patients and the healthy leprosy contacts were not significant with the exception of peptide S9048 (P = 0.0163).