Extracellular vesicles in cancer and lung diseases

Extracellular vesicles (EVs) are small mediators of cellular interactions, secreted by all cell types, and abundantly found in body fluids. They specifically package a wide variety of bioactive molecules, such as proteins, nucleic acids, or metabolites, which are often altered in the context of diseases.

In lung diseases and particularly sarcoidosis, a granulomatous disease with unknown etiology, EVs have been shown to have an altered protein signature. In Study I, EVs originating from sarcoidosis patients were used to stimulate monocytic cells, which secreted more pro-inflammatory cytokines than healthy controls, suggesting a role of EVs in sustaining a pro-inflammatory environment. Study II focused on the characterization of the metabolomic content of EVs, comparing sarcoidosis to two other lung diseases (chronic obstructive pulmonary disease, COPD, and a variant of Myositis, anti-synthetase syndrome, ASyS). In line with clinical manifestations, patients with sarcoidosis and ASyS showed similarity in their EV metabolic profile, further separated from COPD and healthy controls. Interestingly, some pathways were specifically enriched in sarcoidosis EVs, unraveling manifestations of a disrupted metabolism detected in EVs.

Besides their role in disease progression, EVs can also be used as markers to help guide diagnosis. Study III investigated urinary EVs from patients with urinary bladder cancer and healthy controls, characterized by proximity extension assay. A protein signature specific for bladder cancer patients was identified and additional proteins were correlated with muscle-invasiveness. Furthermore, a classifier was able to distinguish muscle-invasive samples from the rest with an accuracy of 92% based on the EV protein profile, paving the way for future EV biomarker studies in urinary bladder cancer.

Finally, Study IV focused on improving the use of EVs as cancer immunotherapy. Combining antigen-loaded EVs from bone marrow derived dendritic cells, with checkpoint blockade inhibitors (anti-PD1 and anti-PD-L1) did not improve the treatment of established tumors, but using the EVs as a prophylactic cancer vaccine had a synergistic effect with anti-PD-L1 therapy, inducing an anti-tumor response in a checkpoint refractory melanoma mouse model.

In conclusion, the work in this thesis focuses on the various roles of EVs in lung diseases and cancer by studying their function in disease progression, their cargo, or tuning their immune-stimulatory effect in a therapeutic setting.

List of scientific papers

I. Casper J. E. Wahlund, Gözde Güçlüler Akpinar, Loïc Steiner, Ahmed Ibrahim, Elga Bandeira, Rico Lepzien, Ana Lukic, Anna Smed- Sörensen, Susanna Kullberg, Anders Eklund, Johan Grunewald, Susanne Gabrielsson. Sarcoidosis exosomes stimulate monocytes to produce pro- inflammatory cytokines and CCL2. Scientific Reports. 10, 15328 (2020). https://doi.org/10.1038/s41598-020-72067-7

II. Loïc Steiner, Hasnat Noor, Ralph Evaristo Claret Monte, Elga Bernardo Bandeira De Melo, Chantal Reinhardt, Carl Wengse, Maria Eldh, Begum Horuluoglu, Anders Linden, Lena Palmberg, Ingrid Lundberg, Susanna Kullberg, Carl Wengse, Gözde Güçlüler Akpinar, and Susanne Gabrielsson. BALF extracellular vesicles from patients with Sarcoidosis and Anti- synthetase Syndrome exhibit metabolic similarities, differing from those in patients with Chronic Obstructive Pulmonary Disease and healthy individuals. [Manuscript]

III. Loïc Steiner, Maria Eldh, Annemarijn Offens, Rosanne E. Veerman, Markus Johansson, Tammer Hemdan, Hans Netterling, Ylva Huge, Abdul-Sattar Aljabery Firas, Farhood Alamdari, Oskar Liden, Amir Sherif and Susanne Gabrielsson. Protein profile in urinary extracellular vesicles is a marker of malignancy and correlates with muscle invasiveness in urinary bladder cancer. Cancer Letters. 609, 217352 (2025). https://doi.org/10.1016/j.canlet.2024.217352

IV. Rosanne E. Veerman, Gözde Güclüler Akpinar, Annemarijn Offens, Loïc Steiner, Pia Larssen, Andreas Lundqvist, Mikael C. I. Karlsson, Susanne Gabrielsson. Antigen-Loaded Extracellular Vesicles Induce Responsiveness to Anti-PD-1 and Anti-PD-L1 Treatment in a Checkpoint Refractory Melanoma Model. Cancer Immunology Research. 11 217-227 (2023). https://doi.org/10.1158/2326-6066.cir-22-0540