Gene Expression Profiling of Nerve Biopsies from Pure Neural Leprosy Patients

Leprosy may affect skin and nerves, leading to disability. Pure neural leprosy (PNL) lacks skin lesions, complicating diagnosis. Transcriptomic profiling reveals unique gene expression changes in PNL nerves, shedding light on immune response and pathogenesis. These findings may guide early diagnosis and improve patient outcomes. In the present study, gene profiling of nerve biopsies from patients with PNL revealed significant transcriptomic alterations compared to non-leprosy controls. Principal Component Analysis (PCA) of the 500 most differentially expressed genes separated the groups, with 1,199 genes showing differential expression (|log2FC| ≥ 1, FDR ≤ 0.1). Downregulated genes included GAS2L2, TRIM67, IL1RAPL1, MAP1LC3B2, and NTNG1, implicated in neuronal development and autophagy, while upregulated genes were linked to immune responses. Functional analyses highlighted inflammasome activation and autophagy impairment in PNL, correlating with nerve inflammation and architecture loss. We hope that our data will aid in identifying new markers, fostering strategies for early diagnosis, preventing disabilities, and improving the management of PNL patients. Nerve biopsies from pure neural leprosy (n = 7) and non-leprosy vasculitis (n = 9) patients were used. Samples come from convenience during routine diagnosis in an outpatient clinic in Rio de Janeiro, RJ, Brazil. Samples from patients with vasculitis were used as a control for non-infectious inflammatory peripheral neuropathy.