Analysis of gut microbiome dynamics in patients with type 1 autoimmune pancreatitis before and after glucocorticoid...

Type 1 autoimmune pancreatitis (AIP) is a rare inflammatory pancreatic disease. Emerging evidence suggests that gut microbiota dysbiosis may contribute to the pathogenesis of type 1 AIP. However, no study has systematically characterized gut microbiota alterations before and after glucocorticoid treatment in patients with type 1 AIP.

Fecal samples were collected from 45 healthy controls (HC), 61 patients with type 1 AIP before glucocorticoid treatment, and 27 patients after glucocorticoid treatment for metagenomic sequencing. To investigate the potential role of Streptococcus anginosus in the development of type 1 AIP, heat-killed Streptococcus anginosus was administered by oral gavage in an AIP mouse model.

Significant differences in both α-diversity and β-diversity were observed among HC and the pre- and post-treatment groups. Compared with the HC group, the pre-treatment group showed increased abundances of Streptococcus, Streptococcus anginosus, and Streptococcus salivarius, along with decreased abundances of Blautia and Dorea formicigenerans. Moreover, the abundances of Streptococcus and Streptococcus anginosus were reduced in the post-treatment group. In the AIP mouse model, oral gavage with heat-killed Streptococcus anginosus significantly increased the pancreatic pathological injury score.

Compared with the HC group, the pre-treatment group showed increased abundances of Streptococcus and Streptococcus anginosus, which were reduced in the post-treatment group. In addition, heat-killed Streptococcus anginosus exacerbated pancreatic injury in the AIP mouse model.