• pd-l1
• R.B.
• S.F

PD-L1 (programmed death-ligand 1) also called CD274 or B7-H1 is a membrane protein involved in the negative regulation of the immune checkpoint, where it determines the non-recognition and removal of cancer cells. Its expression can be of two types: 1) constitutive and low levels, observable on resting lymphocytes, APC cells, corneal cells and Langherans cells, with homeostatic tissue function of inflammatory responses, and 2) an inducible expression at high levels, which is mainly observed in cancer cells of epithelium, endothelium and hematopoietic cells. Three PD-L1 isoforms have been detected: a long form, an isoform with non-coding sequence, and finally a secreted form, also called as truncated form or sec-PD-L1. This variant of splicing has a tail of about 18 amino acids with a final cysteine, and has the ability to dimerize and inhibit the proliferation of T cells by assisting the action of PD-L1 itself. PD-L1 is the main ligand of the PD-1 receptor (programmed death receptor 1) located on the membrane of immune system cells and cancer cells.
For these characteristics, PD-L1 is considered a target of modern therapies and its direct inhibition by immunotherapy, or indirect through different proteins forming part of its molecular pathway, appears a promising approach to the treatment of many types of oncology such as metastatic cancer of lungs and melanoma. Despite of this crucial role, many of the biochemical features of PD-L1 as a membrane protein are still partially unknown. To achieve the overall objective, immunofluorescence protocols, cytometric test, confocal and super-resolution microscopy analysis will be developed. More specifically, the following specific objectives will be pursued:
1. Quantitative morphological analysis of PD-L1 on the cell membrane by confocal microscopy and super-resolution and its relation with the molecular and chemical-physical context of the membrane itself. In particular, the localization of PD-L1 respect to raft membrane zones and its possible modulation in the presence of pharmacological agents will be studied
2. Transcriptional analysis of PD-L1 by rtPCR and its modulation in the presence of pharmacological/chemotherapeutic agents
3. Analysis of PD-L1 cell expression by cytometry and confocal microscopy and its modulation in the presence of pharmacological/chemotherapeutic agents.