• Vaccine Name: rBCG-LTAK63
• Target Pathogen: Mycobacterium tuberculosis
• Target Disease: Tuberculosis
• Type: Live, attenuated vaccine
• Status: Research
• Host Species for Licensed Use: Mouse
• Immunization Route: Intramuscular injection (i.m.)
• Description: The purpose of rBCG-LTAK63 is to create an improved tuberculosis vaccine by enhancing the immune response that standard BCG produces. The recombinant BCG strain expresses the detoxified LTAK63 A-subunit, which acts as a built-in adjuvant to strengthen early and long term protective immunity against mtb. Its goal is to generate faster IFN-? responses, better control of bacteria growth, and reduced lung damage compared to traditional BCG.

Mouse Response

• Host Strain: BALB/c mice
• Host age: 6 week old
• Host gender: female
• Vaccination Protocol: They used female 6 weeks old BALB/c mice, which were immunized once with wither rBCG-LTAK63 or would type BCG at a dose of 1*10^8 CFU delivered subcutaneously into the back. Saline treated mice served as controls. After vaccination, immune responses and gene expression were evaluated at 7 and 90 days post immunization. (Marques-Neto et al., 2025)
• Immune Response: At 7 days post immunization, rBCG-LTAK63 triggers a strong early innate activation: stress genes, autophagy, cAMP, and early IFN-? pathways, much higher than normal BCG. By 90 dpi, this develops into durable immunity, with sustained IFN-? gene activity and stronger Th1/Th17 memory response, showing enhanced long term protection before infection.
• Challenge Protocol: All the mice were challenged intranasally with 500 CFU of M. tuberculosis H37Rv at 90 days.(Marques-Neto et al., 2025)
• Efficacy: rBCG-LTAK63 reducing lung bacterial load by about 1 log at 7 dpc and nearly 2 logs by 30 dpc, while also lowering inflammation and preserving healthy lung tissue.(Marques-Neto et al., 2025)
• Information about this animal model: Mouse Model for TB research