scholarly journals Effects of storage time and temperature on highly multiparametric flow analysis of peripheral blood samples; implications for clinical trial samples

2021 ◽  
Vol 41 (2) ◽  
Author(s):  
Amelia Jerram ◽  
Thomas V. Guy ◽  
Lucinda Beutler ◽  
Bavani Gunasegaran ◽  
Ronald Sluyter ◽  
...  

Abstract We sought to determine the effect of time and temperature of blood sample storage before preparation of human peripheral blood mononuclear cells (PBMCs) by Ficoll-hypaque density gradient centrifugation. Blood samples from healthy donors were stored at room temperature (RT) or refrigerated at 4°C before preparation of PBMCs. Cell yield and viability, and proportions of major cell populations within PBMCs, as determined by fluorescence flow cytometry, were assessed for both fresh and cryopreserved samples. Highly multiparametric mass cytometry was performed on cryopreserved PBMCs. We found that refrigeration had marked negative effects on subsequent PBMC yield. Storage at RT led to co-purification of low density neutrophils with PBMCs, but had no detectable effects on the proportions of multiple cell subsets including, but not limited to, monocytes, NK cells, B cells, Treg cells, and naïve, central memory and effector memory CD4+ and CD8+ T cells and CD45RA-positive terminal effector CD8+ T cells. Expression of a number of cell surface receptors, including CXCR5, CCR6, CXCR3 and TIGIT, but not CD247 was reduced after RT storage before PBMC preparation, and this effect correlated with the degree of low density neutrophil contamination. As such, when PBMC preparation cannot be undertaken immediately after blood draw, storage at RT is far superior to refrigeration. RT storage leads to neutrophil activation, but does not compromise measurement of PBMC subset distribution. However caution must be applied to interpretation of cytometric measurements of surface molecules such as chemokine receptors.

2004 ◽  
Vol 78 (19) ◽  
pp. 10370-10377 ◽  
Author(s):  
Anthony Sanchez ◽  
Matthew Lukwiya ◽  
Daniel Bausch ◽  
Siddhartha Mahanty ◽  
Angela J. Sanchez ◽  
...  

ABSTRACT Peripheral blood samples obtained from patients during an outbreak of Ebola virus (Sudan species) disease in Uganda in 2000 were used to phenotype peripheral blood mononuclear cells (PBMC), quantitate gene expression, measure antigenemia, and determine nitric oxide levels. It was determined that as the severity of disease increased in infected patients, there was a corresponding increase in antigenemia and leukopenia. Blood smears revealed thrombocytopenia, a left shift in neutrophils (in some cases degenerating), and atypical lymphocytes. Infected patients who died had reduced numbers of T cells, CD8+ T cells, and activated (HLA-DR+) CD8+ T cells, while the opposite was noted for patients who survived the disease. Expression levels of cytokines, Fas antigen, and Fas ligand (TaqMan quantitation) in PBMC from infected patients were not significantly different from those in uninfected patients (treated in the same isolation wards), nor was there a significant increase in expression compared to healthy volunteers (United States). This unresponsive state of PBMC from infected patients despite high levels of circulating antigen and virus replication suggests that some form of immunosuppression had developed. Ebola virus RNA levels (virus load) in PBMC specimens were found to be much higher in infected patients who died than patients who survived the disease. Similarly, blood levels of nitric oxide were much higher in fatal cases (increasing with disease severity), and extremely elevated levels (≥150 μM) would have negatively affected vascular tone and contributed to virus-induced shock.


2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e20648-e20648
Author(s):  
Rathi Narayana Pillai ◽  
Alice O. Kamphorst ◽  
Shu Yang ◽  
Taofeek Kunle Owonikoko ◽  
Gabriel Sica ◽  
...  

e20648 Background: Anti PD-1 and PDL-1 antibodies are now established immune targeted therapies for a subset of patients with advanced non-small cell lung cancer (NSCLC). There is a need for predictive biomarkers to better guide patient selection. We profiled peripheral blood samples from patients receiving PD-1 pathway targeted antibodies for lymphocyte subsets and correlated temporal changes with clinical response. Methods: NSCLC patients treated at our institution with PD-1 or PDL-1 inhibitors (nivolumab, pembrolizumab, and atezolizumab) consented to an IRB-approved biomarker profiling protocol. We collected baseline peripheral blood samples before first treatment and subsequently prior to each new treatment cycle until progression of disease or for a maximum of six cycles. Peripheral blood mononuclear cells (PBMCs) were isolated and analyzed by flow cytometry for kinetics of proliferation of PD1+CD8+ T cells. Clinical response to anti PD-1 therapy was classified according to Response Evaluation Criteria in Solid Tumors (RECIST1.1) criteria and correlated with T cell proliferation kinetics. Results: We enrolled 27 patients with baseline characteristics: median age 66, male 70%, smokers 85%, adenocarcinoma 70%; 10 (37%) patients achieved partial response (PR), 7 (26%) had stable disease (SD) and 10 (10%) had disease progression (PD) as best response. There was a > 1.5-fold increase in Ki67+CD8+ T cells expressing PD-1 within 4 weeks of treatment initiation in 80% of patients with PR compared with 30% in patients with SD and 30% in those with PD. Conclusions: Early proliferation of PD1+CD8+ T cells in peripheral blood is a potential pharmacodynamic biomarker of anti PD-1 immunotherapy that could serve as a tool to identify the NSCLC patient subset most likely to respond to PD-1 and PDL-1 inhibitors.


2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1323.1-1323
Author(s):  
R. Reitsema ◽  
R. Hid Cadena ◽  
W. Abdulahad ◽  
A. Boots ◽  
P. Heeringa ◽  
...  

Background:Giant cell arteritis (GCA) is the most frequent form of systemic vasculitis affecting the large- and medium-sized vessels. The involvement of innate immune cells and CD4+ T cells in the pathogenesis of GCA has been extensively studied. Interestingly, recent findings suggest a role for CD8+ T cells in disease development (1). However, CD8+ subsets and their functional capacities have not yet been studied in detail.Objectives:This study aims to characterize the phenotype and proliferative capacity of CD8+ T cells in newly diagnosed GCA patients and GCA patients in remission compared to healthy age- and sex- matched controls.Methods:To determine the phenotype of CD8+ T cells in GCA, newly diagnosed, untreated GCA patients (baseline, n=14), GCA patients in stable glucocorticoid-free remission (GC-FR, n=10) and age- and sex-matched healthy controls (HCs, n=18) were enrolled. Peripheral blood mononuclear cells (PBMCs) were stained with fluorochrome-conjugated antibodies directed against CD3, CD4, CD8, CCR7, CD45RO, Ki-67, CD69 and CD25 and analyzed by flow cytometry. The following differentiation subsets were defined: CD8+ T naive (CD45RO-CCR7+), central memory (TCM, CD45RO+CCR7+), effector memory (TEM, CD45RO+CCR7-) and effector memory re-expressing CD45RA (TEMRA, CD45RO-CCR7-) cells. Secondly, the proliferative capacity of CD8+ T cells was determined in isolated CD3+ T cells of 10 GCA baseline, 10 GCA GC-FR patients and 19 HCs after 5 days of stimulation with plate-bound anti-CD3 or anti-CD3 plus soluble anti-CD28 using a dye-based proliferation assay.Results:A reduced frequency of CD8+ TEMcells was found in GCA baseline patients compared to HCs (p=0.025). Furthermore, a higher frequency of Ki-67+ cells was detected among CD8+ TEMcells in GCA baseline patients than in HCs (p=0.0007), suggesting a higher proliferative activityin vivo.In addition,in vitrostimulation with anti-CD3 and anti-CD3+anti-CD28 led to higher percentages of divided CD8+ T cells in GCA baseline and GC-FR patients than in HCs (p<0.05). Moreover, the frequencies of CD8+ TEMRAcells and the percentage of divided CD8+ T cells upon CD3 stimulation strongly correlated in GCA baseline patients (R=0.79, p=0.009) and GCA GC-FR patients (R=0.67, p=0.039) but not in HCs (R=0.31, p=0.25).Conclusion:GCA baseline patients demonstrate a higher frequency of proliferating circulating CD8+ TEMcells, defined by Ki-67 expression, than HCs. In addition, functional data on induced proliferative capacity suggest that CD8+ T cells from GCA baseline patients are more rapidly activated by crosslinking CD3 and CD3+CD28, suggesting either reduced regulation in these patients or more intrinsic threshold changes. Furthermore, the induced proliferative capacity is also elevated in patients in stable glucocorticoid-free remission. Whether the increased proliferative capacity of total CD8+ T cells in GCA patients is causally linked to the increased frequencies of CD8+ TEMRAcells in these patients requires further investigation.References:[1]Samson M, Ly KH, Tournier B, Janikashvili N, Trad M, Ciudad M, et al. Involvement and prognosis value of CD8+ T cells in giant cell arteritis. J Autoimmun. 2016;72:73–83.Disclosure of Interests:Rosanne Reitsema: None declared, Rebeca Hid Cadena: None declared, Wayel Abdulahad: None declared, Annemieke Boots Consultant of: Grünenthal Gmbh until 2017, Peter Heeringa: None declared, Elisabeth Brouwer Consultant of: Roche (consultancy fee 2017 and 2018 paid to the UMCG), Speakers bureau: Roche (2017 and 2018 paid to the UMCG)


2021 ◽  
Vol 67 (2) ◽  
pp. 95-101
Author(s):  
Monica Vuță ◽  
Ionela-Maria Cotoi ◽  
Ion Bogdan Mănescu ◽  
Doina Ramona Manu ◽  
Minodora Dobreanu

Abstract Objective: In vitro cytokine production by peripheral blood mononuclear cells (PBMCs) is an important and reliable measure of immunocompetence. PBMC can be stimulated directly after isolation or frozen for later use. However, cryopreservation may affect cell recovery, viability and functionality. This study aims to investigate cytokine synthesis in ex-vivo stimulated fresh and cryopreserved CD4+ and CD4- T cells. Methods: PBMCs were obtained by Ficoll gradient centrifugation from heparinized peripheral blood of 6 middle-aged clinically healthy subjects. Half of these cells (labeled “Fresh”) was further processed and the other half (labeled “Cryo”) was cryopreserved at -140°C for up to 3 months. Fresh-PBMCs were activated with Phorbol-Myristate-Acetate/Ionomycin/Monensin for 5 hours immediately after isolation while Cryo-PBMCs were identically activated after thawing and cell resting. Activated cells were fixed, permeabilized and intracellular cytokine staining was performed using Phycoerythrin (PE)-conjugated antibodies for Interleukin-2 (IL-2), Tumor Necrosis Factor-alpha (TNF-a), and Interferon-gamma (IFN-g). All samples were analyzed within 24 hours by flow cytometry. Results: Both Fresh and Cryo CD3+CD4+/CD3+CD4- sub-populations partially produced each of the three cytokines. A higher percentage of CD4+ T cells produced IL-2 and TNF-a and a greater percentage of CD4- T cells were found to produce IFN-g. A significantly higher percentage of Cryo-lymphocytes was shown to produce TNF-a in both CD3+CD4+ (31.4% vs 24.9%, p=0.031) and CD3+CD4- (22.7% vs 17.9%, p=0.031) subpopulations. No notable difference was found for IL-2 and IFN-g production between Fresh and Cryo T cells. Conclusion: Cryopreservation for up to 3 months significantly increases TNF-a production of T-cells in clinically healthy middle-aged subjects.


2021 ◽  
Vol 14 (673) ◽  
pp. eabc5763 ◽  
Author(s):  
Hema Kothari ◽  
Corey M. Williams ◽  
Chantel McSkimming ◽  
Fabrizio Drago ◽  
Melissa A. Marshall ◽  
...  

IL-1β is a key mediator of the cytokine storm linked to high morbidity and mortality from COVID-19, and IL-1β blockade with anakinra and canakinumab during COVID-19 infection has entered clinical trials. Using mass cytometry of human peripheral blood mononuclear cells, we identified effector memory CD4+ T cells and CD4−CD8low/−CD161+ T cells, specifically those positive for the chemokine receptor CCR6, as the circulating immune subtypes with the greatest response to IL-1β. This response manifested as increased phosphorylation and, thus, activation of the proinflammatory transcription factor NF-κB and was also seen in other subsets, including CD11c+ myeloid dendritic cells, classical monocytes, two subsets of natural killer cells (CD16−CD56brightCD161− and CD16−CD56dimCD161+), and lineage− (Lin−) cells expressing CD161 and CD25. IL-1β also induced a rapid but less robust increase in the phosphorylation of the kinase p38 as compared to that of NF-κB in most of these immune cell subsets. Prolonged IL-1β stimulation increased the phosphorylation of the transcription factor STAT3 and to a lesser extent that of STAT1 and STAT5 across various immune cell types. IL-1β–induced production of IL-6 likely led to the activation of STAT1 and STAT3 at later time points. Interindividual heterogeneity and inhibition of STAT activation by anakinra raise the possibility that assays measuring NF-κB phosphorylation in response to IL-1β in CCR6+ T cell subtypes could identify those patients at higher risk of cytokine storm and most likely to benefit from IL-1β–neutralizing therapies.


Sign in / Sign up

Export Citation Format

Share Document