Auto-reactivity against gut bacterial peptides in patients with late-onset diabetes

Abstract

The depletion of gut mucosal barrier enables exposure of gut microbes/gut microbial products to the host mucosal immunity which may increase the risk of metabolic/inflammatory disorders. These immune responses can lead to the development of mild autoimmunity to metabolic peptides coming from gut bacteria and may result in metabolic diseases like late-onset diabetes (LOD). In the present study, we identified host sera cross-reactivity with gut bacterial peptides similar to host proteins. The interaction between diabetic sera and gut peptides was detected by enzyme-linked immunosorbent assay (ELISA) and results were confirmed using surface plasmon resonance (SPR). The ELISA assay showed a higher level of serum cross-reactivity in LOD patients as compared to non-diabetic controls against three peptides (P-5, P-9, and P-13). SPR analysis confirmed binding-affinity against P-5 and P-13. Also, a significant correlation was observed between inflammatory markers and P-5. This study demonstrates that gut health is important not only for intestinal diseases but also for several late-onset diseases, like, diabetes.

Keywords:

• Gut microbes
• gut leakage
• serum cross-reactivity
• autoimmunity
• late-onset diabetes

Acknowledgment

This work is supported by the Department of Biotechnology, New Delhi, India (BT/PR22667/MED/30/1817/2016). The authors thank Director, National Institute of Pathology, ICMR, for the facilities provided for this work.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was financially supported by the Department of Biotechnology, New Delhi, India [BT/PR22667/MED/30/1817/2016].