mRNA mediated expression of novel fusion phage tail protein with antimicrobial peptides inside macrophages for targeted clearance of intracellular Mycobacterium tuberculosis

Current anti-tuberculosis treatments primarily target extracellular Mycobacterium tuberculosis (Mtb), but exhibit limited efficacy against intracellular Mtb, leading to incomplete clearance of pathogens and an increased risk of recurrence. Antimicrobial peptides (AMPs) possess broad-spectrum antimicrobial activity and low potential for resistance development. Here we developed an in vitro mRNA expression platform which not only facilitates intracellular AMPs expression within macrophages, but also significantly enhances their bactericidal activity against Mtb post-infection. Notably, the combination of AMPs trimers demonstrated superior anti-Mtb activity compared to individual AMPs or other combinations. Furthermore, fusion of this AMP complex with either the minor tail protein Gp6 or lysin Gp10 from Mycobacterium phage L5 substantially improved macrophage-specific targeting and intracellular Mtb elimination. Thus, our current study provides novel insights and innovative strategies for the treatment of tuberculosis or other intracellular bacterial pathogens.