Identification of fatigue biomarkers in treated and treatment-naive HIV patients: preliminary results.

Objective assessment in human immunodeficiency virus (HIV)-related fatigue has been elusive because the biological mechanisms are not well characterized. We tried to identify low-abundance plasma proteins that correlate with self-reported fatigue intensity in people living with HIV. We used plasma samples from 32 patients with HIV with varying degrees of fatigue who were either treated with nucleoside reverse transcriptase inhibitors or treatment naïve. The plasma samples were enriched for low-abundance proteins and trypsinized. The peptides were analyzed using shotgun proteomics. Five targets correlated with severity of fatigue: apolipoprotein A-1 (ApoA1), apolipoprotein B (ApoB), histine-rich glycoprotein, alpha-1 B glycoprotein, and orosomucoid 2. These targets were selected based on total abundance and spectral count differences, and ApoA1 and ApoB were analyzed via Western blots to verify the mass spectrometry results. ApoA1 levels were higher in untreated patients, while ApoB results suggested a possible positive trend in treated patients. Further analysis is needed to identify additional low-abundance proteins and confirm already-identified proteins as potential fatigue biomarkers.