Attenuated Listeria monocytogenes vaccine vector (Lm)

Attenuated Listeria monocytogenes vaccine vectors are genetically modified strains of the bacterium Listeria monocytogenes, engineered for safety by deleting key virulence genes. As a live microbial vector, Lm can infect antigen-presenting cells, deliver tumor- or pathogen-associated antigens directly into the cytosol, and stimulate potent, cell-mediated immune responses. Prominent in cancer immunotherapy, Lm vectors increase infiltration and activity of effector T cells, reduce immunosuppressive populations in the tumor microenvironment, and can be further combined with other treatments (such as checkpoint blockade) to enhance antitumor immunity. Safety is managed by attenuation strategies, with ongoing research aimed at balancing immunogenicity and safety, as well as optimizing antigen delivery.

Other names

Attenuated LmListeria vaccine vectorLm-based immunotherapyListeria monocytogenes vaccinerecombinant Listeria monocytogenes

Delivery of antigens via intracellular infection of APCs, leading to antigen presentation through MHC class I and II pathways; Stimulation of robust cytotoxic T lymphocyte (CTL) and helper T cell responses; Reduction in immunosuppressive regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs); Polarization of tumor-associated macrophages towards an anti-tumor phenotype