Simplified platelet sample preparation for SDS-PAGE-based proteomic studies.

Platelet proteomics requires reliable sample preparation methods. Current techniques often involve complex steps that may delay analysis. Storing platelet-rich plasma (PRP) is common but its impact on proteomic outcomes is unclear. Previous studies have not fully addressed the stability of platelet proteins during storage. This uncertainty limits the practicality of proteomic studies in clinical settings. Researchers have explored various storage conditions but results remain inconsistent. The need for a simple and reproducible protocol is evident. This study aims to clarify how storage affects platelet proteomes.

This study aimed to develop a streamlined protocol for platelet sample preparation. The focus was on simplifying the process for proteomic analysis using 2DE and Coomassie blue staining. The researchers wanted to determine if PRP could be stored without compromising proteomic data. They tested storage durations from 0 to 7 days at 4°C. The goal was to identify a timeframe where protein profiles remain stable. This would allow for more flexible sample handling in clinical settings. The study also aimed to quantify how many proteins change during storage. The findings could improve the feasibility of proteomic studies in real-world scenarios.

Blood was collected into EDTA-coated tubes to prevent clotting. Platelet-rich plasma was obtained via centrifugation immediately after collection. Samples were stored in closed Falcon tubes at 4°C for 0 to 7 days. Platelets were isolated by centrifugation at each time point. Two-dimensional electrophoresis (2DE) was used to separate proteins. Gels were stained with colloidal Coomassie blue for visualization. Protein spots were analyzed using Progenesis SameSpots software. Differing spots were excised and identified via nanoLC-MS/MS.

Twenty protein spots showed significant differences over 7 days of storage. Nine of these spots were consistently different across all donors in the first 2 days. Fourteen distinct proteins were identified from these spots. ANOVA analysis confirmed statistical significance (p < 0.05). The majority of changes occurred after day 2 of storage. Protein profiles remained stable for the first 48 hours. No significant differences were found in the first 2 days for nine key spots. These results suggest a 2-day storage window for reliable proteomic analysis.

The study supports the use of EDTA-anticoagulated PRP for up to 2 days. Storing PRP at 4°C does not significantly alter the platelet proteome within this window. This finding allows for more flexible sample handling in proteomic studies. Researchers can delay platelet isolation without compromising data quality. The protocol simplifies sample preparation for clinical proteomics. The results apply to all donors tested in the study. The 2-day timeframe is critical for maintaining protein stability. These conclusions are based on the observed protein spot differences and statistical analysis.