Investigation of exosomal tetraspanin profile in sepsis patients as a promising diagnostic biomarker

Abstract

Introduction

Sepsis, a leading cause of mortality globally, has a complex and multifaceted pathophysiology which still requires elucidation. Therefore, this study aimed to analyze and quantify the number of exosomes in sepsis patients from a South African cohort using the ExoView (NanoView Biosciences, Boston, MA) platform.

Methods

Blood samples were collected from black South African patients attending the local Intensive Care Unit (ICU) hospital. Exosomes were isolated and characterize via TEM and CD63 ELISA kits. ExoView was used to determine particle count, particle size distribution and colocalization of different tetraspanin markers.

Results

Exosomal levels in sepsis patients were significantly higher compared to the control group (p < 0.05). Sepsis exosomes showed a homogenous size distribution ranging from 55 to 70 nm. Tetraspanin colocalization analysis revealed that sepsis exosomes have significantly higher CD63/CD9, CD63/CD81 and CD63/CD9/CD81 colocalization percentages than the control group.

Conclusion

This unique tetraspanin colocalization pattern of sepsis exosomes could serve as a potential sepsis biomarker. Further investigations are required to identify sepsis exosomal cargo signatures for further understanding of sepsis pathophysiology in order to develop effective diagnostics and treatments.

GRAPHICAL ABSTRACT

Keywords:

• Sepsis
• exosomes
• ExoView
• pathophysiology
• tetraspanin
• colocalization

Acknowledgment

The authors acknowledge the College of Health Sciences, the University of KwaZulu-Natal UKZN), National Research Foundation of South Africa.

Ethical approval

Ethical approval was obtained from the Biomedical Research Ethics Committee of the University of KwaZulu-Natal (BREC/00004587/2022) and the South African Department of Health (NHRD: KZ_202107_008).

Authors’ contribution

Roushka Bhagwan Valjee: Sample collection, Investigation, Methodology, Conceptualization, Formal Analysis, writing of the original draft. Irene Mackraj: Conceptualization, Writing revision and editing, Provision of resources and Supervision. Roshila Moodley: Writing revision and editing, Provision of resources. Usri H. Ibrahim: Investigation, Formal Analysis, writing of the original draft preparation, reviewing, and editing.

Disclosure statement

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

Data availability statement

The data that support the findings of this study are available from the corresponding author, [Usri Ibrahim], upon reasonable request.

Additional information

Funding

This work was supported by the College of Health Sciences, the University of KwaZulu-Natal UKZN), National Research Foundation of South Africa (Grant No. 129331).