Thymosin Alpha-1 Restores Chemotherapy-Induced Antitumor Immunity by Chaperoning a MicroRNA Ligand of TLR7 in Dendritic Cells.

Thymosin alpha-1 restores chemotherapy-induced antitumor immunity by protecting microRNA ligands of TLR7 in dendritic cells, enhancing tumor control in mice.

• Why it matters: Chemotherapy often hampers immune responses by releasing poorly immunogenic apoptotic bodies, creating a barrier to effective immunotherapy. Restoring immune activation after chemotherapy is crucial for improving cancer treatment outcomes.
• What they did: Researchers measured thymosin alpha-1 levels in cancer patients and mice, then demonstrated its binding to tumor apoptotic bodies and microRNAs like miR146a-5p, which it protected from degradation, enabling TLR7 activation and dendritic cell maturation.
• The result: Supplementing thymosin alpha-1 synergized with chemotherapy to significantly inhibit tumor growth via TLR7-dependent immune activation, highlighting its potential to boost post-chemotherapy antitumor immunity.