Impact of cell cycle dynamics on pathology recognition: Raman imaging study

Area of Science:

• Biomedical Optics
• Cell Biology
• Spectroscopy

Background:

• Cell cycle phase influences cellular biochemistry and phenotype.
• Distinguishing pathological cells requires understanding cellular heterogeneity.
• Raman spectroscopy offers label-free biochemical analysis of cells.

Purpose of the Study:

• To investigate the impact of cell cycle phase on the discrimination of pathological cells.
• To assess how cell confluency and pathological conditions affect Raman spectroscopic analysis of cell cycle phases.
• To determine the feasibility of using Raman imaging and cell sorting for cell phase analysis.

Main Methods:

• Confocal Raman imaging and fluorescence-activated cell sorting were employed for in vitro cell culture studies.
• Cell cultures were analyzed at different confluency levels (70% and 100%).
• Cells were studied under control conditions, with tumor necrosis factor alpha (TNF-α), and with cytochalasin B.

Main Results:

• High cell confluency (100%) led to phenotypically similar cells across different cycle phases, hindering Raman spectral recognition.
• Lower confluency (70%) allowed for spectroscopic differentiation between cell cycle phases (G0/G1, S, G2/M) in control and TNF-α treated cells.
• Incubation with cytochalasin B rendered Raman signatures of cell cycle phases inseparable.
• Heterogeneity between control and inflamed cells was often greater than heterogeneity between cell cycle phases.

Conclusions:

• Cell confluency significantly impacts the ability to discriminate cell cycle phases using Raman spectroscopy.
• Pathological conditions and treatments can alter cellular heterogeneity, influencing cell discrimination.
• Raman spectroscopy is a valuable tool for analyzing cellular biochemical differences, but its effectiveness is context-dependent on factors like cell density and biological state.