Salt-sensitive hypertension is an independent predictor of death due to cardiovascular disease (CVD), but the mechanisms are poorly understood. Most of the research on salt-sensing mechanisms has focused on the kidney, the vasculature and the brain; however, recent studies from our laboratory have found that immune cells including antigen presenting cells (APCs) can sense sodium (Na+) and contribute to salt-induced hypertension and end organ damage through a mechanism involving increased lipid oxidation and formation of immunogenic gamma ketoaldehydes known as isolevuglandins (IsoLGs) or isoketals. Emerging evidence suggests that Na+ accumulates in the interstitium and activates immune cells but the specific tissue location including the origin, antigenic site, and final target for salt-activated immune cell in cardiovascular tissues is not known. Tools to study T cells have been rapidly expanding over the past 5 years along with increased computing capacity including single T cells sequencing of ? and ? chain T cell receptor spectra typing but very few studies have investigated APCs using these advanced techniques and we do not know where or how they are activated and in turn activate T cells in salt-induced CVD. We propose an innovative approach to use 5? CITE-Seq and post hoc sequencing, to phenotype APCs in people with salt-sensitivity of blood pressure. We will couple the immune phenotype with IsoLG formation using our innovative approach to conjugate the anti- IsoLG D11 ScFv antibody sequence with an oligo and use CITE-Seq to track these important activated IsoLG-positive cells and determine if these are associated with gene expression of sodium channels. Identifying the immune cells associated with salt-sensitivity of blood pressure will have a far-ranging impact on our understanding of the pathogenesis of salt-induced hypertension and other diseases aggravated by high salt consumption.
Excess dietary salt contributes to inflammation and aggravates cardiovascular disease. A major problem with excess salt consumption is that 50% of the hypertensive and 25% of the normotensive population exhibits salt-sensitivity of blood pressure which is an independent predictor of death due to cardiovascular disease. Proposed studies will determine if immune cell activation correlates with salt-sensitivity of blood pressure and may lead to more targeted diagnosis and therapy for salt- induced hypertension.
