scholarly journals Intracellular Concentrations of Posaconazole in Different Compartments of Peripheral Blood

2010 ◽  
Vol 54 (7) ◽  
pp. 2928-2931 ◽  
Author(s):  
Fedja Farowski ◽  
Oliver A. Cornely ◽  
Jörg J. Vehreschild ◽  
Pia Hartmann ◽  
Tim Bauer ◽  
...  
Keyword(s):  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Fungal Infections ◽  
Gradient Centrifugation ◽  
Plasma Concentrations ◽  
Therapeutic Drug ◽  
Peripheral Blood Mononuclear ◽  
Liquid Chromatography Tandem Mass ◽  
Intracellular Concentrations ◽  
High Concentrations

ABSTRACT Therapeutic drug monitoring (TDM) of antifungal plasma concentrations is increasingly recommended. However, data on antifungal concentrations in the other compartments of the peripheral blood are limited. Hence, we collected 23 blood samples from 14 patients receiving posaconazole for prophylaxis of fungal infections. These samples were separated by double-discontinuous Ficoll-Hypaque density gradient centrifugation. The intracellular posaconazole concentrations of the obtained cells, i.e., the peripheral blood mononuclear cells (PBMCs), polymorphonuclear leukocytes (PMNs), and red blood cells (RBCs), were determined by liquid chromatography-tandem mass spectrometry. The intracellular concentrations of the PBMCs and PMNs were significantly higher than those of surrounding media (P < 0.001). The ratios between the intracellular and extracellular concentrations (C/E) were 22.5 ± 21.2, 7.66 ± 6.50, and 0.09 ± 0.05 for the PBMCs, PMNs, and RBCs, respectively. Posaconazole reaches high concentrations within human PBMCs and PMNs and is, to a lesser extent, present in RBCs. The high intracellular concentrations might contribute to posaconazole efficacy and distribution.

scholarly journals No Evidence for Induction of ABC Transporters in Peripheral Blood Mononuclear Cells in Humans after 14 Days of Efavirenz Treatment

2010 ◽  
Vol 54 (10) ◽  
pp. 4185-4191 ◽  
Author(s):  
Jürgen Burhenne ◽  
Anne-Kathrin Matthée ◽  
Ivana Pasáková ◽  
Claudia Röder ◽  
Tilman Heinrich ◽  
...  
Keyword(s):  
Peripheral Blood Mononuclear Cells ◽  
Abc Transporters ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Plasma Concentrations ◽  
Antiretroviral Drugs ◽  
Peripheral Blood Mononuclear ◽  
Blood Mononuclear Cells ◽  
Intracellular Concentrations

ABSTRACT Intracellular concentrations of antiretroviral drugs in peripheral blood mononuclear cells (PBMCs) are an important determinant of therapeutic success. In vitro data indicate that efavirenz induces several ATP-binding cassette (ABC) transporters, and pharmacogenetic studies found an association between ABCB1(C3435T) and efavirenz exposure and between this polymorphism and improved virological outcomes. We therefore aimed to clarify whether efavirenz also induces ABC transporters in vivo in PBMCs and whether intracellular concentrations might be altered after induction. Twelve healthy individuals received multiple oral doses of efavirenz over 14 days (400 mg once daily). Blood samples were drawn on study days 1 (single dose) and 14 (multiple dose), and efavirenz concentrations were analyzed by liquid chromatography-tandem mass spectrometry. Expression of P glycoprotein (P-gp) and of the multidrug resistance-associated proteins 1 and 2 as well as P-gp activity was analyzed in PBMCs on day 1 and day 14 using real-time reverse transcription-PCR (RT-PCR) and rhodamine 123 efflux. Although a clear autoinduction could be confirmed by a significant decrease of efavirenz exposure from day 1 to day 14, efavirenz did not change expression of the ABC transporters or P-gp activity in PBMCs. Moreover, intracellular concentrations of efavirenz were 1.3- to 1.8-fold higher than the corresponding plasma concentrations, and the intracellular/plasma concentration ratio remained constant during the treatment and did not correlate with ABC transporter expression or function. In conclusion, our study confirmed that intracellular concentrations of efavirenz are independent from these efflux transporters and demonstrated for the first time that the transporters are not induced in PBMCs in vivo after 2 weeks of treatment with efavirenz.

scholarly journals Impact of SARS-CoV-2 infection on the recovery of peripheral blood mononuclear cells by density gradient

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Maria D. I. Manunta ◽  
Giuseppe Lamorte ◽  
Francesca Ferrari ◽  
Elena Trombetta ◽  
Mario Tirone ◽  
...  
Keyword(s):  
Density Gradient ◽  
Peripheral Blood Mononuclear Cells ◽  
Peripheral Blood ◽  
Early Phase ◽  
Mononuclear Cells ◽  
Early Stage ◽  
Gradient Centrifugation ◽  
Peripheral Blood Mononuclear ◽  
Blood Mononuclear Cells ◽  
Circulating Lymphocytes

AbstractSARS-CoV-2 virus infection is responsible for coronavirus disease (COVID-19), which is characterised by a hyperinflammatory response that plays a major role in determining the respiratory and immune-mediated complications of this condition. While isolating peripheral blood mononuclear cells (PBMCs) from whole blood of COVID-19 patients by density gradient centrifugation, we noticed some changes in the floating properties and in the sedimentation of the cells on density medium. Investigating this further, we found that in early phase COVID-19 patients, characterised by reduced circulating lymphocytes and monocytes, the PBMC fraction contained surprisingly high levels of neutrophils. Furthermore, the neutrophil population exhibited alterations in the cell size and in the internal complexity, consistent with the presence of low density neutrophils (LDNs) and immature forms, which may explain the shift seen in the floating abilities and that may be predictive of the severity of the disease. The percentage of this subset of neutrophils found in the PBMC band was rather spread (35.4 ± 27.2%, with a median 28.8% and IQR 11.6–56.1, Welch’s t-test early phase COVID-19 versus blood donor healthy controls P < 0.0001). Results confirm the presence of an increased number of LDNs in patients with early stage COVID-19, which correlates with disease severity and may be recovered by centrifugation on a density gradient together with PBMCs.

scholarly journals Monitoring Tacrolimus Concentrations in Whole Blood and Peripheral Blood Mononuclear Cells: Inter- and Intra-Patient Variability in a Cohort of Pediatric Patients

2021 ◽  
Vol 12 ◽  
Author(s):  
Amedeo De Nicolò ◽  
Michele Pinon ◽  
Alice Palermiti ◽  
Antonello Nonnato ◽  
Alessandra Manca ◽  
...  
Keyword(s):  
Peripheral Blood Mononuclear Cells ◽  
Whole Blood ◽  
Peripheral Blood ◽  
Pediatric Patients ◽  
Mononuclear Cells ◽  
Individual Variability ◽  
Peripheral Blood Mononuclear ◽  
Blood Mononuclear Cells ◽  
Intracellular Concentrations ◽  
The One

Tacrolimus (TAC) is a first-choice immunosuppressant for solid organ transplantation, characterized by high potential for drug-drug interactions, significant inter- and intra-patient variability, and narrow therapeutic index. Therapeutic drug monitoring (TDM) of TAC concentrations in whole blood (WB) is capable of reducing the incidence of adverse events. Since TAC acts within lymphocytes, its monitoring in peripheral blood mononuclear cells (PBMC) may represent a valid future alternative for TDM. Nevertheless, TAC intracellular concentrations and their variability are poorly described, particularly in the pediatric context. Therefore, our aim was describing TAC concentrations in WB and PBMC and their variability in a cohort of pediatric patients undergoing constant immunosuppressive maintenance therapy, after liver transplantation. TAC intra-PBMCs quantification was performed through a validated UHPLC–MS/MS assay over a period of 2–3 months. There were 27 patients included in this study. No significant TAC changes in intracellular concentrations were observed (p = 0.710), with a median percent change of −0.1% (IQR −22.4%–+46.9%) between timings: this intra-individual variability was similar to the one in WB, −2.9% (IQR −29.4–+42.1; p = 0.902). Among different patients, TAC weight-adjusted dose and age appeared to be significant predictors of TAC concentrations in WB and PBMC. Intra-individual seasonal variation of TAC concentrations in WB, but not in PBMC, have been observed. These data show that the intra-individual variability in TAC intracellular exposure is comparable to the one observed in WB. This opens the way for further studies aiming at the identification of therapeutic ranges for TAC intra-PBMC concentrations.

scholarly journals Low-Density Granulocyte Contamination From Peripheral Blood Mononuclear Cells of Patients With Sepsis and How to Remove It – A Technical Report

2021 ◽  
Vol 12 ◽  
Author(s):  
Judith Schenz ◽  
Manuel Obermaier ◽  
Sandra Uhle ◽  
Markus Alexander Weigand ◽  
Florian Uhle
Keyword(s):  
Healthy Volunteers ◽  
Density Gradient ◽  
Peripheral Blood Mononuclear Cells ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Density Gradient Centrifugation ◽  
Gradient Centrifugation ◽  
Low Density ◽  
Peripheral Blood Mononuclear ◽  
Blood Mononuclear Cells

Elucidating the mechanisms contributing to the dysregulated host response to infection as part of the syndrome is a current challenge in sepsis research. Peripheral blood mononuclear cells are widely used in immunological studies. Density gradient centrifugation, a common method, is of limited use for blood drawn from patients with sepsis. A significant number of low-density granulocytes co-purify contributing to low purity of isolated peripheral blood mononuclear cells. Whole blood anticoagulated with lithium heparin was drawn from patients with sepsis (n=14) and healthy volunteers (n=11). Immediately after drawing, the plasma fraction was removed and PBMC were isolated from the cellular fraction by density gradient centrifugation. Samples derived from patients with sepsis were subsequently incubated with cluster of differentiation 15 MicroBeads and granulocytes were depleted using magnetic-activated cell sorting. Core cellular functions as antigen presentation and cytokine secretion were analyzed in cells isolated from healthy volunteers (n=3) before and after depletion to confirm consistent functionality. We report here that depleting CD15+ cells after density gradient centrifugation is a feasible way to get rid of the low-density granulocyte contamination. Afterwards, the purity of isolated, functionally intact peripheral blood mononuclear cells is comparable to healthy volunteers. Information on the isolation purity and identification of the containing cell types are necessary for good comparability between different studies. Depletion of CD15+ cells after density gradient centrifugation is an easy but highly efficient way to gain a higher quality and more reliability in studies using peripheral blood mononuclear cells from septic patients without affecting the functionality of the cells.

scholarly journals Relationship between plasma and intracellular concentrations of bedaquiline and its M2 metabolite in South African patients with rifampin-resistant TB

2021 ◽  
Author(s):  
Precious Ngwalero ◽  
James C.M. Brust ◽  
Stijn W. van Beek ◽  
Sean Wasserman ◽  
Gary Maartens ◽  
...  
Keyword(s):  
High Performance ◽  
Mononuclear Cells ◽  
Plasma Concentrations ◽  
Maximum Effect ◽  
Population Pharmacokinetic ◽  
Primary Metabolite ◽  
Peripheral Blood Mononuclear ◽  
Plasma Ratio ◽  
Intracellular Concentrations

Bedaquiline is recommended for the treatment of all patients with rifampin-resistant tuberculosis (RR-TB). Bedaquiline accumulates within cells, but its intracellular pharmacokinetics have not been characterized, which may have implications for dose optimization. We developed a novel assay using high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) to measure the intracellular concentrations of bedaquiline and its primary metabolite M2 in patients with RR-TB in South Africa. Twenty-one participants were enrolled and underwent sparse sampling of plasma and peripheral blood mononuclear cells (PBMCs) at months 1, 2 and 6 of treatment and at 3 and 6 months after bedaquiline treatment completion. Intensive sampling was performed at month 2. We used non-compartmental analysis to describe plasma and intracellular exposures and a population pharmacokinetic model to explore the relationship between plasma and intracellular pharmacokinetics and the effects of key covariates. Bedaquiline concentrations from month 1 to month 6 of treatment ranged from 94.7 – 2540 ng/mL in plasma and 16.2 – 5478 ng/mL in PBMCs and concentrations of M2 over the six-month treatment period ranged from 34.3 – 496 ng/mL in plasma and 109.2 – 16764 ng/mL in PBMCs. Plasma concentrations of bedaquiline were higher than M2, but intracellular concentrations of M2 were considerably higher than bedaquiline. In the pharmacokinetic modeling, we estimated a linear increase in the intracellular-plasma accumulation ratio for bedaquiline and M2, reaching maximum effect after 2 months of treatment. The typical intracellular-plasma ratio 1 and 2 months after start of treatment was 0.61 (95%CI: 0.42-0.92) and 1.10 (95%CI: 0.74-1.63) for bedaquiline and 12.4 (95%CI: 8.8-17.8) and 22.2 (95%CI: 15.6-32.3) for M2. The intracellular-plasma ratio for both bedaquiline and M2 was decreased by 54% (95%CI: 24-72%) in HIV-positive patients compared to HIV-negative patients. Bedaquiline and M2 were detectable in PBMCs 6 months after treatment discontinuation. M2 accumulated at higher concentrations intracellularly than bedaquiline, supporting in vitro evidence that M2 is the main inducer of phospholipidosis.

scholarly journals Separation and Optimisation of a Sucrose Density Gradient Centrifugation Protocol for Isolation of Peripheral Blood Mononuclear Cells (PBMC)

2018 ◽  
pp. 1-4
Author(s):  
Sudeep Nagaraj ◽  
Shubha Nivargi ◽  
Leelavathy Nanjappa ◽  
Jagadish Tavarekere Venkataravanappa
Keyword(s):  
Density Gradient ◽  
Peripheral Blood Mononuclear Cells ◽  
Peripheral Blood ◽  
Blood Cells ◽  
Mononuclear Cells ◽  
Density Gradient Centrifugation ◽  
Gradient Centrifugation ◽  
Peripheral Blood Mononuclear ◽  
Blood Mononuclear Cells ◽  
One Step

One step centrifugation procedure used commonly for separation of blood cells is the ficoll gradient centrifugation. In this method, after centrifugation, the peripheral blood mononuclear cells (PBMCs) are located on the top of the separation fluid, whereas other blood cells erythrocytes and granulocytes sediment to the bottom. In the present study 75% of lymphocyte suspension could be separated by using a one-step density gradient centrifugation of sodium heparin blood with Sucrose. Sucrose was diluted into different concentrations using miliQ water (10%, 20%, 30%, 40%, 50%, 60%,70%, 80%, 90%, 100%,). 4 mL of diluted blood was layered on 4 mL of each sucrose solution and centrifuged for 45 minutes at 1000 rpm. Clear separation of PBMCs could be observed in solution with 40% sucrose. The separated PBMCs were analysed in haeme analyser which showed 75% lymphocytes, 23% monocytes and 2% of other cells.

MO678DISTRIBUTION OF PERIPHERAL BLOOD T CELL SUBTYPES IN HEMODIALYSIS PATIENTS TREATED WITH MEDIUM CUT-OFF MEMBRANES AND HIGH-FLUX MEMBRANES

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Nuri Baris Hasbal ◽  
Mustafa Sevinç ◽  
Vuslat Yilmaz ◽  
Taner Basturk ◽  
Elbis Ahbap Dal ◽  
...  
Keyword(s):  
Risk Factors ◽  
T Cell ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Gradient Centrifugation ◽  
High Flux ◽  
Peripheral Blood Mononuclear ◽  
Immune Balance ◽  
Stage Renal Disease ◽  
End Stage

Abstract Background and Aims Mortality in end stage renal disease is higher than in the general population. In addition, there is also an increase in mortality that cannot be explained by known risk factors. In this context, researchers have been determining on these additional risk factors for years. Although inflammation is a proven risk factor, further studies are still needed. In this study, we aimed to investigate the effect of membranes on the distribution of T cell subgroups in peripheral blood mononuclear cells (PBMC) that play an important role in inflammation. Method Twenty-five patients were enrolled in the study, and patients received hemodialysis treatment first with MCO membrane (MCO) for 3 months and then with high-flux membrane (HF) for another 3 months. Peripheral blood samples were taken from the patients just before the hemodialysis procedure at 0 (starting with MCO), 3rd (switching to HF) and 6th (end of study) months. PBMC’s were separated by ficoll density gradient centrifugation and stored in liquid nitrogen. Frozen cells were stained with fluorescently labeled monoclonal antibodies and were utilized with flow cytometry device. Data were analyzed using FlowJo7.6.5 programs. Results Proportions of helper T (CD3+CD4+), cytotoxic T (CD3+CD8+), and follicular helper T (CD3+CD4+ CXCR3-CXCR5+) cells were similar in both membranes. The use of MCO decreased the ratios of peripheral CD3+T (p=0.07) and Th1 (CD3+CD4+CXCR3+CCR6+) (p&lt;0.0001) cells while increasing the ratio of NK cells (p=0.03). In addition, the shift of the immune balance towards an increase in Th17 (CD3+CD4+CXCR3-CCR6+) (p=0.005) and Th2 (CD3+CD4+CXCR3-CCR6-) (p &lt;0.0001) cell ratios with HF. Conclusion : The results can be interpreted as the prevention of a Th1 dominant inflammation seen with HF. Therefore, it suggests that the use of MCO may reduce T cell based inflammation in peripheral blood.

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