Biodiversity and Its Double-Edged Role in the Pathogenesis of Type 1 Diabetes

Over the past decade, research into the mechanistic pathways and causal factors of type 1 diabetes has revealed increasing complexity in its pathogenesis. The immune system is a key mediator between the genomics of an individual who is susceptible to type 1 diabetes and the immediate environment. 1 Sims EK Carr ALJ Oram RA DiMeglio LA Evans-Molina C 100 years of insulin: celebrating the past, present and future of diabetes therapy. Nat Med. 2021; 27: 1154-1164 Crossref PubMed Scopus (44) Google Scholar At present, contrasting postulations exist regarding the basis of islet cell autoimmunity, and the nature of the environmental trigger has yet to be elucidated. There are considerations for the viral hypothesis, whereby an inciting viral infection, such as the human enterovirus, sets off a cascade of immunological and proinflammatory processes, culminating in β cell destruction. 2 Hull CM Peakman M Tree TIM Regulatory T cell dysfunction in type 1 diabetes: what's broken and how can we fix it?. Diabetologia. 2017; 60: 1839-1850 Crossref PubMed Scopus (102) Google Scholar Conversely, the biodiversity hypothesis has also gained traction, proposing that microbiota diversity and stability maintains immune balance, and its disruption causes disarray resulting in the development of autoimmune diseases, including type 1 diabetes. 3 Haahtela T A biodiversity hypothesis. Allergy. 2019; 74: 1445-1456 PubMed Google Scholar SARS-CoV-2 and type 1 diabetes in children in Finland: an observational studyChildren and adolescents diagnosed with type 1 diabetes during the pandemic had a more severe disease at diagnosis. The observed increase in type 1 diabetes incidence during the first 18 months could be a consequence of lockdown and physical distancing rather than a direct effect of SARS-CoV-2 infection. Full-Text PDF