Optimized flow cytometry protocol for dihydrorhodamine 123-based detection of reactive oxygen species in leukocyte subpopulations in whole blood

Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved..

Reactive oxygen species (ROS) and the ability of immune cells to mount an oxidative burst represent an important defense during microbial invasion, but is also recognized for playing a significant role in the progression of inflammatory disorders and disease. Although neutrophils produce the strongest ROS-response, other leukocytes and their cell subsets could play a significant role. Isolation of specific cells for determining their ROS-response can affect their functionality and is laborious or hard to replicate in different settings. We have therefore established a whole blood assay, that only requires 100 μL heparinized blood and utilizes the dihydrorhodamine (DHR) 123 ROS-probe combined with cell surface antibody staining for the specific detection of ROS in several subsets of cells simultaneously using flow cytometry. Although the flow markers chosen are interchangeable with other direct conjugated and cell specific antibodies depending on the research question, we focused on neutrophils (SSChighCD16brightHLA-DRneg/low), eosinophils (SSChighCD16lowHLA-DRlow/negCD193positiveCD125positive) and monocyte subsets (SSCintermediateHLA-DRhighCD14low-positiveCD16negative-positive). As a RBC-lysis reagent we compared BD FACS Lysis Solution to the in-house prepared ammonium-chloride‑potassium based ACK Lysis Buffer, that does not fix or permeabilize the immune cells. We find that ACK-lysis of stimulated and stained samples results in superior surface staining, decreased loss of cell subsets, and enhanced resolution of the DHR-signal. Compared to the other cells analyzed in healthy blood donors, neutrophils responded with the highest ROS-response to all tested stimuli (fMLP (low stimuli), E. coli, and PMA (high stimuli)), where eosinophils and the three monocyte subsets also showed an extensive ROS-response when stimulated with E. coli or PMA. Our assay provides the possibility for researchers to examine the ROS-response of specific cell subsets in specific patient groups ex vivo and could also allow the analysis of pharmacological intervention studies targeting ROS, which ultimately can advance the field of immunological research.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:507

Enthalten in:

Journal of immunological methods - 507(2022) vom: 15. Aug., Seite 113308

Sprache:

Englisch

Beteiligte Personen:

Pioch, Jonathan [VerfasserIn]
Blomgran, Robert [VerfasserIn]

Links:

Volltext

Themen:

109244-58-8
Classical monocytes
Dihydrorhodamine 123
Eosinophils
HLA-DR Antigens
Intermediate monocytes
Journal Article
Neutrophils
Non-classical monocytes
Reactive Oxygen Species
Receptors, IgG
Research Support, Non-U.S. Gov't
Rhodamines

Anmerkungen:

Date Completed 14.07.2022

Date Revised 22.08.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.jim.2022.113308

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM342810790