Analysis of changes in immune cells lipid fingerprint after their in-vitro activation

Abstract

[eng] During last decade cancer therapies have undergone constant progress, as reflected in the development of novel histological methods for diagnosis, personalized chemotherapy and targeted therapy. Despite progress made in colorectal cancer (CRC) field, little can be done to improve overall survival, even on early CRC stages (II-III), besides surgical resection in combination with chemotherapy. Therefore, new biomarkers for early detection of the disease, more innovative methods for patient stratification and the development of new immunotherapeutic treatments become essential. Importantly, several studies have shown that the tumor microenvironment plays a crucial role in CRC progression. In this context, this study aimed to lay the groundwork for the first characterization of the membrane lipid fingerprint of sorted immune cells, which eventually may infiltrate the tumor. For that end, our purpose was to establish the lipidome of each cell type using MALDI-IMS technology, which exhibits a much higher sensitivity compared to other MS technologies. Unexpectedly, this approach could not be directly applied in sorted cells, as the spectra obtained were lacking the most relevant peaks. Consequently, the study aims was reevaluated and it was focused on investigating the reason of such failure and on setting up a successful procedure. The latter is essential for the optimal development of one of the current research lines of the group. Thus, the procedure described here should allow us characterizing the lipidome of any type of immune cells, even for rare populations, of which there is no information available yet. The thorough description of immune cells lipidome will also help for a better comprehension of the complex network of interactions prevailing within the tumor microenvironment.