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Mäkinen, L.

Publications and source records attributed to Mäkinen, L..

2 recordsLinked to original sources

Multivalent mRNA tuberculosis vaccines protect against mycobacterial infection in zebrafish, mice and guinea pigs

Despite a century of BCG use, tuberculosis remains a leading cause of death from infectious diseases and more effective vaccines are urgently needed. Here we combined antigen discovery in zebrafish with mRNA vaccine technology to generate multivalent vaccine candidates, TUmRNA4, TUmRNA6 and TUmRNA9, encoding four, six, or nine Mycobacterium tuberculosis antigens, respectively. The vaccines were well tolerated, and induced robust antigen-specific cellular immune responses, including IFN{gamma} production and expansion of memory T-cell populations. In mice, TUmRNA4 and TUmRNA6 reduced pulmonary M. tuberculosis burden and lung pathology to levels comparable to BCG vaccination and TUmRNA6 enhanced BCG-mediated protection when used as a booster vaccine. In guinea pigs, TUmRNA9 reduced bacterial burden in the lungs, spleen, and lymph nodes and decreased pulmonary lesions. These findings demonstrate that protective antigens identified in zebrafish can be translated into effective multivalent mRNA vaccines and establish a framework for tuberculosis vaccine development across multiple preclinical models.

immunology↗

Parallel evolution of phage resistance - virulence trade - offs during in vitro and nasal Pseudomonas aeruginosa phage treatment

With rising antibiotic resistance, there has been increasing interest in treating pathogenic bacteria with bacteriophages (phage therapy). One limitation of phage therapy is the ease at which bacteria can evolve resistance. Negative effects of resistance may be mitigated when resistance results in reduced bacterial growth and virulence, or when phage coevolve to overcome resistance. Resistance evolution and its consequences are contingent on the bacteria-phage combination and their environmental context, making therapeutic outcomes hard to predict. One solution might be to conduct "in vitro evolutionary simulations" using bacteria-phage combinations from the therapeutic context. Overall, our aim was to investigate parallels between in vitro experiments and in vivo dynamics in a human participant. Evolutionary dynamics were similar, with high levels of resistance evolving quickly with limited evidence of phage evolution. Resistant bacteria - evolved in vitro and in vivo - had lower virulence. In vivo, this was linked to lower growth rates of resistant isolates, whereas in vitro phage resistant isolates evolved greater biofilm production. Population sequencing suggests resistance resulted from selection on de novo mutations rather than sorting of existing variants. These results highlight the speed at which phage resistance can evolve in vivo, and in vitro experiments may give useful insights for clinical evolutionary outcomes.

evolutionary biology↗