Genome-wide screening of mRNA expression in leprosy patients

In this study, a comprehensive assessment of human mRNA was performed on leprosy skin lesions using DNA chip microarrays, which included the entire spectrum of the disease along with its reactional states. Sixty-six samples from leprotic lesions (10TT, 10BT, 10BB, 10BL, 4LL, 14R1, and 10R2) and nine skin biopsies from healthy individuals were used as controls (CC) (ages ranged from 06 to 83 years, 48 were male and 29 female). The evaluation identified differentially expressed mRNAs [Fold Change (FC)≥2.0, p<0.05] in disease lesions versus healthy controls or between them. Some of these genes were validated by RT-PCR and/or immunohistochemistry. The sequence of events for this study followed the order below. Patients who were treated for leprosy were examined by leprologists and submitted to two biopsy procedures. One biopsy was processed for histopathological analysis, bacilloscopy and immunohistochemistry (IHC), the other was immediately stored in RNAlater® solution (Ambion) for further RNA extraction. Sixty-eight samples from leprotic lesions (10TT, 10BT, 10BB, 10BL, 4LL, 14R1, and 10R2) were selected for analysis. In addition, nine skin biopsies from healthy individuals were usedas controls (CC). Differentially expressed genes identified in the cDNA microarray assay were validated by quantitative RT-PCR and IHC.