Environmental Diagnosis through a Flow Cytometric Approach

Abstract

In an era when ecological and environmental needs and responsibilities apply pressure on the world's countries and sustainability takes centre stage, ecologic/environmental (E/E) laboratories stand as beacons of scientific inquiry, innovating, optimising, and applying various tests for a better knowledge of our natural resources and the quality status of ecosystems. The purpose of this review is to provide an overview of the use of flow cytometry (FC) as a tool for assessing environmental quality, mainly using living organisms and their biological changes as bioindicators. Cytometric approaches applied to both marine and terrestrial ecosystems ensure the detection of biochemical and functional status of the cells composing either an organ thereof or the organism itself. In addition to cytometric evaluations of the biotic matrix, a brief overview of the techniques for the environmental assessment of biotic and abiotic matrices using mass spectrometry is given. The technique involving the continuous monitoring of the chemical and physical parameters of water, sediment, and soil is basically incapable of detecting any additive and synergetic effects of toxicants on living organisms. Therefore, techniques employing bioindicators provide valuable information for environmental diagnosis, and several studies have demonstrated the strong relationship between specific environmental data and cell/organ behaviour.

Keywords: bioindicator; biomarker; haemolymph; hepatopancreas; marine; terrestrial.

Figure 1

Schematic diagram showing different biological indicators to assess pollution (plants and animals—earthworms, bivalve molluscs, foraminifera, insects, crustacea, lichens, raptor, etc.); biodiversity (animals, plants, and microbial communities); and climate change (plants and animals—migratory birds, insects, and coral). Created in biorender.com, accessed on 1 June 2024.

Figure 2

The main fields of application of biomarkers and the information they can provide. Created in biorender.com, accessed on 3 June 2024.

Figure 3

Flow cytometer’s fluidic, optical, and electronic systems depicted in a schematic diagram. Photomultiplier tubes (PMTs), Fluorescent channel (FL), Side Scatter (SSC), Forward Scatter (FSC), and analogue-to-digital converters (ADCs). Created in biorender.com, accessed on 5 June 2024.

Figure 4

Schematic diagram of protocol steps for analysing haemolymph (isopods and mussels) and cells from the hepatopancreas tissue after disaggregation (isopods) using flow cytometry and confocal microscopy. Created in biorender.com, accessed on 7 June 2024.

Figure 5

Representative dot plots of FSC vs. SSC and fluorescence histograms for the quantitative evaluation of specific dye MFIs (mean fluorescence intensities) in cells obtained from the following: (A), hepatopancreas of Armadillidium vulgare; (B) haemolymph of A. vulgare, and (C) haemolymph of Mytilus galloprovincialis.

Figure 6

Keyword co-occurrence network map with respect to total link strength.

Figure 7

Keyword co-occurrence network map with respect to total link strength with the score of the average publication year of the documents. Overlay network created with flow cytometry and ecological–environmental topics.