Identification of Endothelial Proteins in Plasma Associated With Cardiovascular Risk Factors

Abstract

Objective: Endothelial cell (EC) dysfunction is a well-established response to cardiovascular disease risk factors, such as smoking and obesity. Risk factor exposure can modify EC signaling and behavior, leading to arterial and venous disease development. Here, we aimed to identify biomarker panels for the assessment of EC dysfunction, which could be useful for risk stratification or to monitor treatment response. Approach and Results: We used affinity proteomics to identify EC proteins circulating in plasma that were associated with cardiovascular disease risk factor exposure. Two hundred sixteen proteins, which we previously predicted to be EC-enriched across vascular beds, were measured in plasma samples (N=1005) from the population-based SCAPIS (Swedish Cardiopulmonary Bioimage Study) pilot. Thirty-eight of these proteins were associated with body mass index, total cholesterol, low-density lipoprotein, smoking, hypertension, or diabetes. Sex-specific analysis revealed that associations predominantly observed in female- or male-only samples were most frequently with the risk factors body mass index, or total cholesterol and smoking, respectively. We show a relationship between individual cardiovascular disease risk, calculated with the Framingham risk score, and the corresponding biomarker profiles. Conclusions: EC proteins in plasma could reflect vascular health status.

Lipid Profiles of Human Serum Fractions Enhanced with CD9 Antibody-Immobilized Magnetic Beads

“…Serum and plasma are relatively easy samples to use for routine diagnosis, and since they circulate throughout the body, they are thought to reflect various disease states [ 4 ]; at the same time, the markers from lesion sites are diluted by a large amount of blood. Therefore, methods to concentrate specific fractions of serum or plasma by immunoprecipitation or other methods have been tried [ 11 , 12 , 13 ]. CD9, a member of the tetraspanin superfamily, has a variety of biological activities and is considered to be functionally crucial [ 19 ].…”

“…However, one of the disadvantages of blood samples is that they are often far from the disease site, and the large volume of blood dilutes the molecules originating from the pathological tissue. Therefore, the density gradient centrifugation methods [ 9 , 10 ] and the immunoprecipitation methods [ 11 , 12 , 13 ] are known to concentrate only specific fractions in serum or plasma. Since the ultracentrifugation method is not suitable for the measurement of multiple samples, we decided to explore the possibility of the immunoprecipitation method.…”

“…Since the ultracentrifugation method is not suitable for the measurement of multiple samples, we decided to explore the possibility of the immunoprecipitation method. The fractionation of serum components by immunoprecipitation has recently been used in proteomics [ 11 , 12 , 13 ], but it has rarely been used in lipidomics.…”

Proteomics in thrombosis research

“…Over the years, affinity‐based assays have moved from the detection a single protein at a time, as in Western blot or enzyme‐linked immunosorbent assay (ELISA), to the measurement of large protein panels for the identification of signatures associated with specific disease conditions or health status. 31 , 33 , 35 , 37 Here, we discuss the three in‐solution technology platforms for large‐scale screening of biomarker candidates that, to date, have been most commonly used for plasma proteomic analysis: the antibody‐based suspension bead array (SBA), 38 the proximity extension assay (PEA), 39 and the aptamer‐based SomaScan assay. 40 All three platforms allow for highly multiplexed profiling of proteins in many samples using a plate‐based format.…”

“…These candidates were explored in the VEBIOS study 22 and more recently in the population‐based Swedish CArdioPulmonary bioImage Study , SCAPIS , identifying endothelial cell proteins associated with cardiovascular disease risk factors and the Framingham risk score. 37 With a similar strategy, Ishizaki et al developed a multiplex SRM MS assay for quantitation of a panel of 135 biomarker candidates for vascular inflammatory disease that included 87 endothelium‐related proteins predicted to be present in blood through in silico screening of public databases. 99 The SRM panel was used to analyze paired plasma samples from 23 and 29 patients with vasculitis before and after treatment, identifying nine markers that were validated by conventional ELISA in 169 patients.…”