Infection with human T-lymphotropic virus 1 (HTLV-1) can lead to severe diseases, including adult T-cell leukemia/lymphoma (ATL). Host proteins whose expression is selectively dysregulated in infected cells may provide targets for therapeutic intervention. To identify markers associated with HTLV-1 infection, we performed a proteomic analysis using lymphoid cell models. Specifically, we analysed two HTLV-1–infected cell lines (MT-2 and MT-4) and one ATL-derived cell line (SP cells), and compared them with three uninfected control lines (Jurkat E6.1, MOLT-4, and CEM-ss).