Hemodialysis-related changes in phenotypical features of monocytes

Abstract

Hemodialysis (HD) patients exhibit chronic inflammation and leukocyte activation. We investigated the surface-marker profile of monocytes by flow cytometry to assess the chronic effect of uremia and the acute effect of dialysis on their phenotypical and functional features in 16 healthy controls (CON) and 15 HD patients before and after a polysulfone-based dialysis session. Median fluorescence intensities were analyzed indicating expression of CD14, CD16, integrins (CD11b, CD18), chemokine receptors (CCR2, CX3CR1), scavenger receptors (CD36, CD163) and Toll-like receptor-2 (TLR2). Before and after dialysis, HD patients harbour 0.9-fold less CD14++CD16− (Mo1), 1.8-fold more CD14++CD16+ (Mo2) and CD14+CD16++ (Mo3) monocytes than CON. HD patients’ Mo1 showed elevated expression of CD11b (1.7-fold), CD18 (1.2-fold) and CD36 (2.1-fold), whereas CD163 expression was reduced in Mo1 and Mo2 (0.6-fold) compared to CON. These markers remained unaffected by dialysis. CX3CR1 expression on Mo2 and Mo3 was lower in HD patients before (0.8-fold) and further diminished after dialysis (0.6-fold). Stimulation of monocytes resulted in diminished responses in HD patients compared to CON. In conclusion, a systematic analysis of the expression of particular surface markers on distinct monocyte subsets may help to distinguish between uremia and/or dialysis induced effects and to evaluate the functionality of monocytes and biocompatibility of HD.

Altered monocytic phenotypes are linked with systemic inflammation and may be linked to mortality in dialysis patients

“…Previously we have shown that dialysis patients possess an altered distribution of peripheral blood monocytes presenting fewer classical and more intermediate and non-classical monocytes 8 . The high incidence of bacterial infection in dialysis patients is largely attributed to monocyte dysfunction 25 . This prompted us to compare the reactivity of monocytes between healthy controls (n = 34) and dialysis patients (n = 45).…”

Tuberculosis among Patients Undergoing Solid Organ Transplantation or Dialysis in a Low-Endemic Country, 2004-2017

“…However, end-stage renal disease (ESRD) is associated with functional abnormalities in a variety of immune cells including dendritic cells, B and T cells, neutrophils, monocytes, and natural killer cells, which is not reversed by dialysis [16]. Dialysis itself may also affect immune function by causing dysfunction of neutrophils, monocytes, and T cells [17][18][19].…”

New Insights into the Roles of Monocytes/Macrophages in Cardiovascular Calcification Associated with Chronic Kidney Disease

“…Hence, in an effort to reduce the patient’s inflammatory state, ultrapure dialysates and other highly biocompatible dialysis materials have been introduced. Indeed, the currently used polysulphone-based dialysis membranes are not associated with abnormal circulating counts of classical CD14++/CD16− monocytes, pro-inflammatory intermediate CD14++/CD16+ monocytes, and non-classical CD14+/CD16++ monocytes in HD patients [191]. However, the elevated TLR2 expression and the concomitantly low CD163 expression observed in intermediate monocytes after HD [191] suggests that exposure to dialysis membranes still increases the inflammatory potential of monocytes in this population.…”

“…Indeed, the currently used polysulphone-based dialysis membranes are not associated with abnormal circulating counts of classical CD14++/CD16− monocytes, pro-inflammatory intermediate CD14++/CD16+ monocytes, and non-classical CD14+/CD16++ monocytes in HD patients [191]. However, the elevated TLR2 expression and the concomitantly low CD163 expression observed in intermediate monocytes after HD [191] suggests that exposure to dialysis membranes still increases the inflammatory potential of monocytes in this population. Interestingly, the number of CD14+/CD16+ pro-inflammatory monocyte count, the plasma cytokine level, and cytokine mRNA expression levels were significantly lower in patients on haemodiafiltration than in those on HD [192].…”