Immune Evasion Mechanisms of Mycobacterium tuberculosis and Their Implications for Vaccine Development: A Systematic Review and Meta-Analysis with Nigerian Data Integration

Mycobacterium tuberculosis employs sophisticated immune evasion strategies that allow it to persist intracellularly, undermining host defenses and rendering the current BCG vaccine insufficient for adult pulmonary TB protection. This systematic review and meta-analysis synthesized evidence on M. tuberculosis immune evasion mechanisms from published literature between 2019 and 2024, with integration of Nigerian clinical immunological data from a subset of TB patients at Aminu Kano Teaching Hospital, Kano State, in the North West geopolitical zone of Nigeria. Forty-three eligible peer-reviewed studies were identified through MEDLINE, Embase, and African Journals Online. Data were extracted on key immune evasion pathways including phagosome maturation arrest, lysosome avoidance, type I interferon induction, and T cell exhaustion. Primary Nigerian data from 60 TB patients provided immunophenotyping validation. Meta-analysis demonstrated that ESX-1 secretion system-mediated phagosome rupture was documented in 87.2 percent of study models, while inhibition of antigen presentation via downregulation of MHC class II occurred in 74.4 percent of reviewed systems. Nigerian patient data showed significantly elevated exhausted CD4 T cell percentages compared to controls. Sub-group analysis indicated that M. tuberculosis immune evasion efficacy was enhanced in malnourished and HIV-co-infected hosts. These integrated findings provide a current mechanistic framework to guide novel TB vaccine antigen selection, particularly targeting ESX-1 and phagosome integrity pathways. Keywords: Mycobacterium tuberculosis, immune evasion, vaccine development, systematic review, Nigeria.