Aberrant function and differentiation of monocytes in end stage renal disease

The Pathogenesis of End-Stage Renal Disease from the Standpoint of the Theory of General Pathological Processes of Inflammation

Chronic kidney disease can progress to end-stage chronic renal disease (ESRD), which requires the use of replacement therapy (dialysis or kidney transplant) in life-threatening conditions. In ESRD, irreversible changes in the kidneys are associated with systemic changes of proinflammatory nature and dysfunctions of internal organs, skeletal muscles, and integumentary tissues. The common components of ESRD pathogenesis, regardless of the initial nosology, are (1) local (in the kidneys) and systemic chronic low-grade inflammation (ChLGI) as a risk factor for diabetic kidney disease and its progression to ESRD, (2) inflammation of the classical type characteristic of primary and secondary autoimmune glomerulonephritis and infectious recurrent pyelonephritis, as well as immune reactions in kidney allograft rejection, and (3) chronic systemic inflammation (ChSI), pathogenetically characterized by latent microcirculatory disorders and manifestations of paracoagulation. The development of ChSI is closely associated with programmed hemodialysis in ESRD, as well as with the systemic autoimmune process. Consideration of ESRD pathogenesis from the standpoint of the theory of general pathological processes opens up the scope not only for particular but also for universal approaches to conducting pathogenetic therapies and diagnosing and predicting systemic complications in severe nephropathies.

Increased accumulation of CD16+ monocytes at local sites of inflammation in patients with chronic kidney disease

Patients with chronic kidney disease (CKD) display a high prevalence of cardiovascular events and acute infections. Potential effector cells are the CD16(+) monocytes, known to be increased in the peripheral circulation in CKD. The aim of this study was to assess the expression of CD16 and CX3 CR1 on peripheral and in vivo extravasated monocytes in patients with CKD (GFR < 20 ml/min × 1.73 m²) using flow cytometry. In vivo extravasated monocytes were collected from a local inflammatory site, induced by a skin blistering technique. Soluble markers were assessed by Luminex. The number of CD16(+) monocytes was significantly higher in patients with CKD compared with healthy subjects, both in the peripheral circulation (P < 0.05) and at the site of induced inflammation (P < 0.001). Patients with CKD displayed significantly higher concentration of soluble CX3 CL1 both in the peripheral circulation (P < 0.01) and in the interstitial fluid (P < 0.001). In addition, patients with CKD had a significantly higher concentration of TNF-α in the peripheral circulation (P < 0.001). On the contrary, at the inflammatory site, concentrations of both TNF-α and IL-10 were significantly lower in patients with CKD compared with healthy controls (P < 0.05 for both). In conclusion, patients with CKD have an increased percentage of CD16(+) monocytes in both circulation and at the inflammatory site, and this finding is in concurrence with simultaneous changes in CX3 CR1. Together with distorted TNF-α and IL-10 levels, this may have potential impact on the altered inflammatory response in CKD.