# The ‘autoimmunome’ of centenarians

## TL;DR

This study identifies proteins in centenarians' blood that may protect against autoimmunity, including elevated albumin and complement system proteins.

## Contribution

The paper introduces the concept of the 'autoimmunome' in centenarians and highlights novel protein signatures linked to autoimmunity resistance.

## Key findings

- Sixteen autoimmune disease-related proteins were identified in centenarians' proteomic signatures.
- Albumin was the most connected hub protein and was elevated in centenarians compared to younger controls.
- Eight autoimmunity-related proteins were linked to the complement system, suggesting its role in autoimmunity resistance.

## Abstract

To identify signature proteins potentially linked to resistance to autoimmunity in the blood of centenarians.

We conducted in silico data mining of previously published proteomic results using the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) and PHENOPEDIA databases.

Sixteen autoimmune disease-related proteins were identified within the proteomic signatures of centenarians. Albumin was the most connected hub protein, notably elevated in centenarians compared to younger controls, suggesting a protective role. Eight of the identified autoimmunity-related proteins—ADIPOQ, C1S, C5, C7, C9, CFD, MASP1, and SERPING1—were associated with the complement system.

Elevated albumin levels and a prominent complement system presence in centenarians' blood proteome may contribute to resistance to autoimmunity, highlighting potential protective mechanisms against autoimmune diseases in extreme longevity.

Graphical abstract summarizing the identification of autoimmune disease (AD)-related proteins in the blood proteome of centenarians. Proteomic data from two independent studies were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and SomaScan platforms. In silico data mining using Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) and PHENOPEDIA identified 16 AD-related proteins. ALB (albumin) emerged as the central hub in the protein–protein interaction (PPI) network and was notably elevated in centenarians compared to younger controls. Eight proteins (see text for symbol explanations)—ADIPOQ, C1S, C5, C7, C9, CFD, MASP1, and SERPING1—were associated with the complement system, supporting its potential role in resistance to autoimmunity in extreme longevity. Created with BioRender.com. Note: Protein identifiers are based on HGNC (HUGO Gene Nomenclature Committee) gene symbols, as used in proteomics and bioinformatics resources such as STRING or PHENOPEDIA. While these symbols technically denote genes, they are used here to represent proteins and are formatted in non-italicized uppercase, in line with standard practice in the field.Image 1