Pathobionts in the microbiome: Drivers of disease and targets for treatment.

Pathobionts are commensal inhabitants of the human microbiome that can transition to a pathogenic state under specific genetic or environmental conditions. They have recently gained attention for their impact on various clinical conditions. This review discusses the key factors behind pathobiont emergence, including microbial dysbiosis, antibiotic use, dietary influences, immune dysfunction and host genetics. It provides a comprehensive overview of pathobionts associated with the gut, oral cavity, and vaginal microbiomes highlighting their roles in disease pathogenesis. A significant focus is also placed on the involvement of pathobiont in immune-related disorders. Furthermore, current and advanced therapeutic strategies aimed at mitigating the effects of pathobionts, such as faecal microbiota transplantation, phage therapy, probiotics and prebiotics, along with their advantages and limitations, were highlighted. Thus, the integrated perspective combining microbial ecology, host immunity, and therapeutic strategies outlines the need for targeted, microbiome-based interventions to address the complex behaviour of pathobionts.