Blood dendritic cell levels associated with impaired IL-12 production and T-cell deficiency in patients with kidney disease: implications for post-transplant viral infections

Abstract

Summary Reduced pretransplant blood myeloid dendritic cell (mDC) levels are associated with post-transplant BK viremia and cytomegalovirus (CMV) disease after kidney transplantation. To elucidate potential mechanisms by which mDC levels might influence these outcomes, we studied the association of mDC levels with mDC IL- 12 production and T-cell level/function. Peripheral blood (PB) was studied in three groups: (i) end stage renal disease patients on hemodialysis (HD; n = 81); (ii) chronic kidney disease stage IV-V patients presenting for kidney transplant evaluation or the day of transplantation (Eval/Tx; n = 323); and (iii) healthy controls (HC; n = 22). Along with a statistically significant reduction in mDC levels, reduced CD8+ T-cell levels were also demonstrated in the kidney disease groups compared with HC. Reduced PB mDC and monocyte-derived DC (MoDC) IL-12 production was observed after in vitro LPS stimulation in the HD versus HC groups. Finally, ELISpot assays demonstrated less robust CD3+ INF-γ responses by MoDCs pulsed with CMV pp65 peptide from HD patients compared with HC. PB mDC level deficiency in patients with kidney disease is associated with deficient IL-12 production and T-cell level/function, which may explain the known correlation of CD8+ T-cell lymphopenia with deficient post-transplant antiviral responses.

Multiparameter Flow Cytometry Assay for Quantification of Immune Cell Subsets, PD‐1 Expression Levels and PD‐1 Receptor Occupancy by Nivolumab and Pembrolizumab

“…After correction for 90% cell recovery, the average cell concentrations we found in healthy volunteers for different immune cell subsets were as follows: 1780 (1278-2,849) PBMCs; 1,156 (508-2013) lymphocytes; 310 (172-620) total monocytes; 101 (57-202) B-cells; 154 (51-202) NK-cells; 6.9 (2.2-18.4) mDCs; and 6.2 (2.7-10) pDCs per μl blood. These values are in concordance with values reported by other investigators (37)(38)(39). Although the normal range for concentrations of immune cell subsets has been reported by many investigators, there is debate regarding both the percentage and the absolute numbers of cells constituting this range.…”

“…Brahmer et al used background controls containing human IgG 4 isotype Table 1C. These values are in concordance with values reported by other investigators (37)(38)(39). Others have reported that using isotype antibodies can give erroneous results, and have shown that adequate blocking of non-specific antibody interactions and using directly conjugated antibodies can most often prevent the use of isotypes in flow cytometry (36).…”

Increased CD1c+ mDC1 with mature phenotype regulated by TNFα–p38 MAPK in autoimmune ocular inflammatory disease

“…For our functional studies, we used MoDCs as a substitute for mDCs in an in vitro model [12, 13, 17]. Six to Seven days are usually needed for monocytes to fully differentiate into mDCs in vitro .…”

“…Monocyte-derived dendritic cells (MoDCs) were generated as previously described and used as an in vitro model for mDCs for additional functional studies [12, 13]. Briefly, monocytes were isolated from mononuclear cell fractions of the peripheral blood of healthy controls and seeded in the presence of GM-CSF (40 ng/ml; R&D systems, Minneapolis, MN) and IL-4 (20 ng/ml; R&D Systems) at a concentration of 1 × 10 6 cells/well in a 6-well plate.…”

Diagnostic performance of cytomegalovirus (CMV) immune monitoring with ELISPOT and QuantiFERON-CMV assay in kidney transplantation

“…[6–8] Therefore, monitoring the CMV-specific cellular immunity has been investigated to better predict the risk of CMV infection among recipients. [9] In general, the most commonly used diagnostic tools based on the principle of CMV-specific cellular immunity include CMV enzyme-linked immunospot (ELISPOT) assays and QuantiFERON-CMV test. The T-cell immune activity of former one could be measured by assessing the interferon-gamma (IFN-γ) production after the stimulation with CMV antigens such as phosphoprotein 65 (pp65) and immediate early 1 (IE-1), whereas the latter one is an enzyme-linked immunosorbent assay (ELISA) tool to test the released levels of IFN-γ in the whole blood by ex vivo stimulation with human leukocyte antigen (HLA) class I-restricted CMV peptides.…”