1. Secrets and lies of host-microbial interactions: MHC restriction and trans-regulation of T cell trafficking conceal the role of microbial agents on the edge between health and multifactorial/complex diseases
- Author
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Ria, Francesco, Delogu, Giovanni, Ingrosso, L, Sali, Michela, Di Sante, Gabriele, Ria, F (ORCID:0000-0002-8444-0307), Delogu, G (ORCID:0000-0003-0182-8267), Sali, M (ORCID:0000-0003-3609-2990), Di Sante, G (ORCID:0000-0001-6608-3388), Ria, Francesco, Delogu, Giovanni, Ingrosso, L, Sali, Michela, Di Sante, Gabriele, Ria, F (ORCID:0000-0002-8444-0307), Delogu, G (ORCID:0000-0003-0182-8267), Sali, M (ORCID:0000-0003-3609-2990), and Di Sante, G (ORCID:0000-0001-6608-3388)
- Abstract
Here we critically discuss data supporting the view that microbial agents (pathogens, pathobionts or commensals alike) play a relevant role in the pathogenesis of multifactorial diseases, but their role is concealed by the rules presiding over T cell antigen recognition and trafficking. These rules make it difficult to associate univocally infectious agents to diseases' pathogenesis using the paradigm developed for canonical infectious diseases. (Cross-)recognition of a variable repertoire of epitopes leads to the possibility that distinct infectious agents can determine the same disease(s). There can be the need for sequential infection/colonization by two or more microorganisms to develop a given disease. Altered spreading of infectious agents can determine an unwanted activation of T cells towards a pro-inflammatory and trafficking phenotype, due to differences in the local microenvironment. Finally, trans-regulation of T cell trafficking allows infectious agents unrelated to the specificity of T cell to modify their homing to target organs, thereby driving flares of disease. The relevant role of microbial agents in largely prevalent diseases provides a conceptual basis for the evaluation of more specific therapeutic approaches, targeted to prevent (vaccine) or cure (antibiotics and/or Biologic Response Modifiers) multifactorial diseases.
- Published
- 2024