Biomimetic mycobacterial dual spatiotemporal targeting induces trained immunity for tuberculosis photothermal immunotherapy and relapse prevention.
TL;DR
These findings show that TDN + AIE@MM integrates physical sterilisation, immunosuppression reversal, and durable immune memory via dual spatiotemporal targeting, effectively addressing the three core challenges in TB therapy, namely delivery barriers, immune evasion, and relapse risk, and offering a promising strategy for immunotherapy and relapse prevention.
Abstract
Background
Tuberculosis (TB) treatment remains hindered by three intertwined challenges, drug delivery barriers, immune evasion, and high relapse rates. Despite advances in nanocarriers and immunomodulation, an integrated platform that achieves precise targeting, potent sterilisation, immune remodelling, and durable protection is still lacking.
Methods
A biomimetic DNA tetrahedral phototherapy system (TDN + AIE@MM) was constructed using Mycobacterium marinum membrane modification to mimic trained immunity and enable dual spatiotemporal targeting of granulomas and lymph nodes. Through natural membrane ligand recognition, the system delivered payloads to immunosuppressive granulomas and antigen-retarded lymph nodes. Upon NIR-II irradiation, the AIE agent generated local hyperthermia to kill intracellular Mycobacterium tuberculosis and released antigens to activate adaptive and long-term memory immune responses.
Findings
TDN + AIE@MM exhibited uniform size, good stability, and preserved membrane proteins. In vitro, it showed superior targeting to H37Ra and macrophages over unmodified controls. Under 808 nm laser irradiation, it achieved >99% killing of extra- and intracellular H37Ra, induced M1 polarisation with pro-inflammatory cytokines (IFN-γ, IL-1β, IL-6, and TNF-α), and enhanced T-cell proliferation and antigen-specific responses. In vivo, it achieved spatiotemporal dual-targeting to granulomas and lymph nodes, increased CD80+/CD86+ antigen-presenting cells and CD4+ T-cell activation, and reduced lung bacterial load. For immune memory, TRM (CD8+CD69+CD103+) reached 21.8% on day 42, approximately two-fold higher than rifampicin (Rif). In a rechallenge relapse model, the 84-day relapse rate was 16.7% versus 66.7% for Rif, with higher memory B cells and TEM, confirming durable protection.
Interpretation
These findings show that TDN + AIE@MM integrates physical sterilisation, immunosuppression reversal, and durable immune memory via dual spatiotemporal targeting, effectively addressing the three core challenges in TB therapy, namely delivery barriers, immune evasion, and relapse risk, and offering a promising strategy for immunotherapy and relapse prevention.
Funding
Prevention and Control of Emerging and Major Infectious Diseases-National Science and Technology Major Project, the Project Department for Supporting the Research and Innovation Capabilities of Young Teachers in Universities-Pilot Program for Provincial Coordination, the National Natural Science Foundation of China, the Yunnan Provincial Department of Science and Technology-Kunming Medical University Special Projects, the Shenzhen University 2035 Program for Excellent Research, and the Scientific Research Fund of the Yunnan Provincial Department of Education.
