Cell Phase Identification in a Three-Dimensional Engineered Tumor Model by Infrared Spectroscopic Imaging

Area of Science:

• Biomedical Engineering
• Spectroscopy
• Cell Biology

Background:

• Cell cycle progression is crucial for cellular functions like proliferation and metabolism.
• Three-dimensional (3D) cell cultures are vital in vitro disease models.
• Integrating cell cycle dynamics into 3D models is essential for accuracy.

Purpose of the Study:

• To utilize Fourier transform infrared (FT-IR) spectroscopic imaging for identifying cell cycle phases (G1/S and G2/M) in 3D cell cultures.
• To establish spectral markers for cell cycle analysis without staining.
• To characterize the impact of cell cycle progression on 3D biological systems.

Main Methods:

• Synchronized 2D cell cultures were analyzed using FT-IR spectroscopic imaging.
• Flow cytometry and DNA quantification confirmed cell cycle states.
• Two specific wavenumbers (1059 and 1219 cm-1) were identified as spectral indicators.

Main Results:

• FT-IR imaging successfully identified G1/S and G2/M phases in 2D and 3D cell cultures.
• Spectral markers distinguished cell cycle stages across normal to metastatic cancer cell lines in 3D models.
• Early 3D acini development showed higher proliferation, with later stages exhibiting stable composition but spatial cell phase differences.

Conclusions:

• FT-IR spectroscopic imaging offers a label-free, quantitative method for cell cycle phase analysis in 3D cultures.
• This approach can characterize cell cycle impacts on tissue-like 3D structures.
• The findings support the use of IR imaging in disease diagnostics and 3D biological system studies.