Applications of MALDI-MS/MS-Based Proteomics in Biomedical Research

Area of Science:

• Proteomics
• Analytical Chemistry
• Biomedical Research

Background:

• Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is a key technique in proteomics.
• It enables structural identification and characterization of proteins and peptides, including proteoforms arising from post-translational modifications (PTMs) or protein-protein interactions (PPIs).
• MALDI-MS and MALDI tandem mass spectrometry (MS/MS) offer high sensitivity and direct analysis of diverse biological samples with minimal preparation.

Purpose of the Study:

• To review the applications of MALDI ionization and tandem MS approaches for analyzing biomedical peptides and proteins.
• To highlight the utility of MALDI-MS/MS in generating "molecular pictures" for in situ protein analysis.
• To discuss the role of histology-directed MALDI-mass spectrometry imaging (MSI) in spatial analysis of biomarkers within tissues.

Main Methods:

• Utilizing MALDI-MS and MALDI-MS/MS for structural identification and characterization of peptides and proteins.
• Employing MALDI-MS/MS for direct analysis of biological samples like biofluids, tissues, and cell lysates.
• Applying histology-directed MALDI-MSI with MALDI-ToF/ToF or other tandem mass spectrometers for in situ analysis.

Main Results:

• MALDI-MS/MS facilitates the deciphering of molecular functions, biological processes, cellular components, and pathways, aiding in disease pathogenesis understanding.
• "Molecular pictures" generated by MALDI-MS/MS offer label-free, in situ information on protein molecular weights.
• Histology-directed MALDI-MSI provides essential spatial data for peptide biomarkers and active compounds directly within tissues.

Conclusions:

• MALDI-MS and its tandem MS variants are indispensable tools in modern proteomics and biomedical research.
• The ability of MALDI-MS/MS to provide in situ molecular imaging and spatial data is crucial for biomarker discovery and understanding disease mechanisms.
• Histology-directed MALDI-MSI complements other techniques by offering essential spatial context for molecular analysis in complex biological samples.