• CD8 + T-cells in atherosclerotic lesions show impaired IFN-γ and TNF-α production, associated with expression of CD39. • TCR signaling is required for the upregulation of CD39 + on lesional CD8 + T-cells. • Pharmacological inhibition of CD39 partly restores cytokine production of CD8 + T-cells in the atherosclerotic lesions. • CD8 + T-cells from human lesions display increased expression of CD39 compared to their circulating counterparts.

BackgroundNeutrophils have been reported to have protumor, antitumor or neutral effects in cancer progression. The underlying causes for this functional variability are not clear.MethodsWe studied the role of neutrophils in six different mouse tumor models by intratumoral injection of antimicrobial peptides or vaccination. Changes in systemic and intratumoral immune cells were analyzed by flow-cytometry and mass-cytometry. The role of neutrophils was studied by antibody-mediated neutrophil depletion. Neutrophils from different mouse strains were compared by RNA sequencing.ResultsThe antimicrobial peptide Omiganan reduced the growth of TC-1 tumors in BL/6 mice and CT26 tumors in BALB/c mice. No significant effects were observed in B16F10, MC38 and 4T1 tumors. Growth delay was associated with increased abundance of neutrophils in TC-1 but not CT26 tumors. Systemic neutrophil depletion abrogated Omiganan efficacy in TC-1 but further reduced growth of CT26, indicating that neutrophils were required for the antitumor effect in TC-1 but suppressed tumor control in CT26. Neutrophils were also required for a therapeutic vaccine-induced T-cell mediated control of RMA tumors in BL/6 mice. Clearly, the circulating and intratumoral neutrophils differed in the expression of Ly6G and CD62L, between TC-1 and CT26 and between blood neutrophils of tumor-naïve BL/6 and BALB/c mice. RNA-sequencing revealed that neutrophils from BL/6 mice but not BALB/c mice displayed a robust profile of immune activation, matching their opposing roles in TC-1 and RMA versus CT26.ConclusionsNeutrophil functionality differs strongly between mouse strains and tumor types, with consequences for tumor progression and therapy.

Background and Aims: Abdominal aortic aneurysms (AAA) have a multifactorial pathology with both genetic and environmental risk factors. Genome-wide association studies have discovered nine genetic risk loci for AAA. Our aim was to investigate to what extent these genetic variants contribute to the aneurysm pathology.