Abstract: TH-PO036

Tonsillar Microbiome in IgA Nephropathy

Session Information

Category: Glomerular

  • 1001 Glomerular: Basic/Experimental Immunology and Inflammation

Authors

  • Park, Ji In, Kangwon National University Hospital, Chuncheon-si,, Korea (the Republic of)
  • Cho, Hyunjeong, Seoul National University Hospital, Jongno- gu, SEOUL, Korea (the Republic of)
  • Lee, Hajeong, Seoul National University College of Medicine, Seoul, Korea (the Republic of)
  • Kim, Dong Ki, Seoul National University Hospital, Jongno- gu, SEOUL, Korea (the Republic of)
  • Yang, Seung Hee, Kidney Research Institute, Seoul National University, Seoul, Korea (the Republic of)
  • Lee, Jung Pyo, Seoul National University Boramae Medical Center, Seoul, Korea (the Republic of)
  • Kim, Yon Su, Seoul National University College of Medicine, Seoul, Korea (the Republic of)
Background

Mucosal immune system plays a role in pathogenesis of Immunoglobulin A nephropathy (IgAN); however, little has been known about the relationship between IgAN and the microbiome reside in tonsil.

Methods

We prospectively enrolled 29 biopsy-proven IgAN patients at 3 centers and collected tonsil swabs at the time of renal biopsy. Tonsil swabs from 29 healthy volunteers who visited hospital for a medical check-up were used as control. The composition of microbiota was analyzed using extracted metagenomic DNA from the tonsil swabs by Illumina MiSeq system. Downstream analyses were performed using SPSS, Phylogenetic reconstruction of unobserved states (PICRUSt), and Linear discriminant analysis Effect Size (LEfSe).

Results

The mean age was 32.4 and 42.9 in control group and IgAN patients group, respectively. Though the age was significantly different between the groups, there was no trend or clustering according to the age groups. Compared to control group, tonsil microbiota of IgAN patients showed significantly higher Shannon diversity index. The relative abundances of Firmicutes and Bacteroidetes were higher, whereas those of Proteobacteria were lower in IgAN patients than healthy subjects. At Genus level, relative abundances of Granulicatella were higher, whereas those of Acinetobacter and Veillonella were significantly lower in the tonsil specimens from IgAN patients compared to healthy subjects. PICRUSt analysis showed that genes involved in galactose metabolism were enriched in IgAN.
By dividing patients on the basis of 3 g/day proteinuria, we tried to figure the microbial difference according to disease severity. However, the bacterial diversity or composition were not differed between severity groups.

Conclusion

The tonsillar microbiota of IgAN patients differed from those of control group although it was not associated with disease severity. In addition, these differences showed possible relation with galactose metabolism which was involved in pathogenesis of IgAN.