# Protein profile of purified plasma- and aqueous humor-derived extracellular vesicles from patients with ocular toxoplasmosis

## TL;DR

This study identifies unique protein profiles in extracellular vesicles from patients with ocular toxoplasmosis, which could help in diagnosing the condition.

## Contribution

The study reports 67 previously unreported proteins in extracellular vesicles from ocular toxoplasmosis and cataract patients.

## Key findings

- Ocular toxoplasmosis aqueous humor extracellular vesicles showed a distinct protein signature compared to cataract patients.
- Sixty-seven new proteins were identified, with 10 unique to cataract and 7 unique to ocular toxoplasmosis patients.
- The identified proteins are linked to immune activation and retinal homeostasis, suggesting relevance to disease mechanisms.

## Abstract

To characterize the extracellular vesicle protein cargo in the aqueous humor and plasma
of patients with ocular toxoplasmosis.

Aqueous humor and plasma were collected from six patients with active ocular
toxoplasmosis and six patients with cataract. Extracellular vesicles were isolated, and
western blotting and mass spectrometry were performed for protein analysis.

All plasma samples from patients with ocular toxoplasmosis and cataract were positive
for the tetraspanins CD63 and TSG101. However, the aqueous humor from patients with
ocular toxoplasmosis was positive only for CD63. Sixty-seven new unreported proteins
were identified in the aqueous humor and plasma of patients with the ocular
toxoplasmosis and cataract. Of the 67 proteins, 10 and 7 were found only in the cataract
and ocular toxoplasmosis groups, respectively. In general, these proteins were involved
in immune system activation and retina homeostasis and were related to infections and
retina-associated diseases.

The distinct protein signatures between ocular toxoplasmosis and cataract may be
helpful in the differential diagnosis of ocular toxoplasmosis. However, more studies are
needed to better understand the role of these proteins in the pathogenesis of ocular
toxoplasmosis.