Determination of proteomic profiles for differential diagnosis of tuberculosis and sarcoidosis

Tuberculosis and sarcoidosis are two granulomatous diseases that sometimes do not have sufficient criteria for definitive diagnosis despite simultaneous clinical, radiological and pathological evaluations. For the differential diagnosis of tuberculosis and sarcoidosis, a total of 20 paraffinized lymph tissue samples obtained from 10 patients with definitive diagnoses from each disease group were subjected to a series of processes to isolate total protein and then separate peptides, and peptide analysis was performed with the LC-QTOFF-MS device. The results were analyzed using the Peaks Studio 12 program. UniProtKB was used as a database for both human proteome and Mycobacterium tuberculin proteome, and proteins with significant differences between these two diseases were determined bioinformatically and statistically. In the analysis based on human proteome, proteins with significant differences in log2 values (2-fold) were taken into account, 5 different proteins that were upregulated in tuberculosis and downregulated in sarcoidosis, 7 different proteins that were upregulated in sarcoidosis and downregulated in tuberculosis were detected, and other related proteins were detected by performing pathway analyses with the STRING program. In addition, 6 Mycobacterium tuberculin proteins that were different from sarcoidosis were found in common in lymphoid tissues of tuberculosis patients. This study sheds light on future studies to discover the differential diagnosis criteria of these two diseases by detecting proteins that differ in tuberculosis and sarcoidosis.