Antiplatelet drugs do not protect from platelet-leukocyte aggregation in coronary artery disease.

BACKGROUND: Despite advances in cardiovascular medicine, coronary artery disease (CAD) remains a leading cause of mortality. Among the pathophysiological features of this condition, platelet-leukocyte aggregates (PLAs) require further attention, either as diagnostic/prognostic disease markers or as potential interventional targets. OBJECTIVES: In this study, we characterized PLAs in patients with CAD. Primarily, we investigated the association of PLA levels with CAD diagnosis. In addition, the basal levels of platelet activation and degranulation were assessed in patients with CAD and controls, and their correlation with PLA levels was analyzed. Finally, the effect of antiplatelet treatments on circulating PLA numbers, basal platelet activation, and degranulation was studied in patients with CAD. METHODS: Participants were recruited at the Department of Cardiology of the University Heart and Vascular Centre Hamburg Eppendorf. Among patients admitted with severe chest pain, the diagnosis of CAD was made angiographically, and patients without CAD were used as controls. PLAs, platelet activation, and platelet degranulation were assessed by flow cytometry. RESULTS: Circulating PLAs and basal platelet degranulation levels were significantly higher in patients with CAD than in controls. Surprisingly, there was no significant correlation between PLA levels and platelet degranulation (or any other measured parameter). In addition, patients with CAD on antiplatelet therapy did not display lower PLA or platelet degranulation levels compared with those in controls. CONCLUSION: Overall, these data suggest a mechanism of PLA formation that is independent of platelet activation or degranulation and highlights the inefficiency of current antiplatelet treatments for the prevention of basal platelet degranulation and PLA formation.

Whole-slide image analysis of the tumor microenvironment identifies low B-cell content as a predictor of adverse outcome in patients with advanced-stage classical Hodgkin lymphoma treated with BEACOPP.

A subset of patients with advanced-stage classical Hodgkin Lymphoma (cHL) relapse or progress following standard treatment. Given their dismal prognosis, identifying this group of patients upfront represents an important medical need. While prior research has identified characteristics of the tumor microenvironment, which are associated with cHL outcomes, biomarkers that are developed and validated in this high-risk group are still missing. Here, we applied whole-slide image analysis (WSI), a quantitative, large-scale assessment of tumor composition that utilizes conventional histopathology slides. We conducted WSI on a study cohort with pre-treatment biopsies of 340 advanced-stage cHL patients enrolled in the HD12 and HD15 trials of the German Hodgkin Study Group (GHSG), and tested our results in in a validation cohort of 147 advanced-stage cHL patients within the GHSG HD18 trial. All patients were treated with BEACOPP-based regimens. By quantifying T cells, B cells, Hodgkin-Reed-Sternberg-cells and macrophages with WSI, 80% of all cells in the tumor tissue were identified. Crucially, low B cell count was associated with significantly reduced progression-free survival (PFS) and overall survival (OS), while T cell-, macrophage- and Hodgkin-Reed-Sternberg-cell content was not associated with the risk of progression or relapse in the study cohort. We further validated low B cell content as a prognostic factor of PFS and OS in the validation cohort and demonstrate good inter-observer agreement of WSI. WSI may represent a key tool for risk stratification of advanced-stage cHL that can easily be added to the standard diagnostic histopathology work-up.