Fig 3. Frequencies of CD4⁺ T cells responsive (CD69⁺) to HLA Class II-restricted M. leprae- specific epitopes in household contacts of multibacillary leprosy patients (HCMB).

(A) Frequencies of central and effector memory CD4⁺ T cells expressing CD69 in response to 6-hr in vitro stimulation with a pool of HLA class II-restricted synthetic peptides derived from M. leprae specific epitopes (15-mers) at T0 and T1. Each black circle represents one HCMB. The red lines represent the median values for the different time points. Changes in the Individual frequencies of central (B) and effector memory T cells (C) responsive to M. leprae specific epitopes are shown. Each bar represents a single contact identified by the number under the bar. Orange bars represent the contacts who received the first BCG dose at T0; the red bar represents the HCMB who received a second BCG dose at T0; and the blue bars represent the HCMB who was not vaccinated at T0. n = 12. * p<0.05.