scholarly journals Functional comaparison of PBMCs isolated by Cell Preparation Tubes (CPT) vs Lymphoprep Tubes

2020 ◽  
Author(s):  
Han Chen ◽  
Christian M Schürch ◽  
Kevin Noble ◽  
Kenneth Kim ◽  
Peter Krutzik ◽  
...  

Abstract Background : Cryopreserved human peripheral blood mononuclear cells (PBMCs) are a commonly used sample type for a variety of immunological assays. Many factors can affect the quality of PBMCs, and careful consideration and validation of an appropriate PBMC isolation and cryopreservation method is important for well-designed clinical studies. A major point of divergence in PBMC isolation protocols is the collection of blood, either directly into vacutainers pre-filled with density gradient medium or the use of conical tubes containing a porous barrier to separate the density gradient medium from blood. Results : To address potential differences in sample outcome, we isolated, cryopreserved, and compared frequency and functionality of PBMCs using parallel protocols differing only in the use of one of two common tube types for isolation. Whole blood was processed in parallel using both Cell Preparation Tubesä (CPT, BD Biosciences) and Lymphoprepä Tubes (Axis-Shield) and assessed for yield and viability prior to cryopreservation. After thawing, samples were further examined by flow cytometry for cell yield, cell viability, frequency of ten cell subsets, and capacity for stimulation-dependent CD4+ and CD8+ T cell intracellular cytokine production. Cell recovery, viability, frequency of immune cell subsets, and T cell functionality between PBMC samples isolated using CPT or Lymphoprep tubes were comparable. Conclusion : CPT and Lymphoprep tubes are both effective for PBMC isolation and may be used interchangeably for immunological studies involving T cell activation.

2020 ◽  
Author(s):  
Han Chen ◽  
Christian M Schürch ◽  
Kevin Noble ◽  
Kenneth Kim ◽  
Peter Krutzik ◽  
...  

Abstract Background: Cryopreserved human peripheral blood mononuclear cells (PBMCs) are a commonly used sample type for a variety of immunological assays. Many factors can affect the quality of PBMCs, and careful consideration and validation of an appropriate PBMC isolation and cryopreservation method is important for well-designed clinical studies. A major point of divergence in PBMC isolation protocols is the collection of blood, either directly into vacutainers pre-filled with density gradient medium or the use of conical tubes containing a porous barrier to separate the density gradient medium from blood. To address potential differences in sample outcome, we isolated, cryopreserved, and compared PBMCs using parallel protocols differing only in the use of one of two common tube types for isolation. Methods: Whole blood was processed in parallel using both Cell Preparation Tubesä (CPT, BD Biosciences) and Lymphoprepä Tubes (Axis-Shield) and assessed for yield and viability prior to cryopreservation. After thawing, samples were further examined by flow cytometry for cell yield, cell viability, frequency of ten cell subsets, and capacity for stimulation-dependent CD4+ and CD8+ T cell intracellular cytokine production. Results: No significant differences in cell recovery, viability, frequency of immune cell subsets, or T cell functionality between PBMC samples isolated using CPT or Lymphoprep tubes were identified.Conclusion: CPT and Lymphoprep tubes are effective and comparable methods for PBMC isolation for immunological studies.


2021 ◽  
Author(s):  
Alessia Furgiuele ◽  
Massimilano Legnaro ◽  
Alessandra Luini ◽  
Marco Ferrari ◽  
Emanuela Rasini ◽  
...  

This protocol was designed to activate the lymphocytes T of a population of peripheral blood mononuclear cells (PBMCs), simulating their physiological response to antigen/MHC complex acting on T Cell Receptors-TCR , in order to test their functional responses including cell proliferation and cytokine production. The co-stimulation protocol include: i)anti-CD3 antibody a polyclonal activator specific for invariant framework epitopes on TCR complex (in particular, we use UCHT1 clone an anti-human CD3 antibody that recognizes the ε-chain of CD3 which is used for immobilized option of activation) (http://static.bdbiosciences.com/documents/BD_Tcell_Human_CD3_Activation_Protocol.pdf) ii) anti-CD28 antibody used to cooperate with TCR signals promoting activation of T cells The procedure has been reproduced following the indications contained in the protocol of "EBiooscience" (https://tools.thermofisher.com/content/sfs/manuals/t-cell-activation-in-vitro.pdf). Pilot experiments on PBMC were carried out to determine the best concentrations of anti-CD3 and anti-CD28 to induce optimal proliferation of PBMC and production of cytokines TNF-α and IFN-γ. We found a dose dependent correlation between immobilized anti-CD3 and cells functional responses. The selected amount was 2 µg/mL for both anti-CD3 and anti-CD28 that was the concentration below the maximum response which allows also to test possible modulations by therapeutic agents. References http://static.bdbiosciences.com/documents/BD_Tcell_Human_CD3_Activation_Protocol.pdf https://tools.thermofisher.com/content/sfs/manuals/t-cell-activation-in-vitro.pdf https://www.bdbiosciences.com/ds/pm/tds/555330.pdf https://www.bdbiosciences.com/ds/pm/tds/555726.pdf BEFORE STARTING with this procedure Moreover, work under laminar flow hood when you are processing samples from the beginning to the end of the culture. Make sure you are using,sterile culture mediumand sterile plastic disposable as well.


2020 ◽  
Vol 3 (Supplement_1) ◽  
pp. 129-130
Author(s):  
V Batura ◽  
C Guo ◽  
N Warner ◽  
G Leung ◽  
A Ricciuto ◽  
...  

Abstract Background IBD is a form of chronic inflammatory disorder of the gastrointestinal tract that arises due to genetic, environmental, immunological and microbial factors. The precise pathological mechanisms remain elusive. It is thought that the onset of pediatric IBD can largely be attributed to genetics. Muise lab, at SickKids, regularly screens children at the SickKids IBD clinic and through an international consortium to find possible genetic links to the disease. We report a patient at SickKids with biallelic mutations in DOK4 who has severe Crohn’s Disease along with other inflammatory conditions. Downstream of kinase (DOK) proteins are a family of adaptor molecules that serve as scaffolding proteins important in regulating cell signaling, especially in T cells. DOK4 has been shown to have negative regulatory effects on T cell activation but is also expressed across various other tissues where its function is yet to be determined. We predict that these mutations are causing immune cell dysregulation, which may be contributing to the patients IBD. Aims Through this study, we aim to enhance our understanding of the pathobiological mechanism of novel mutations in DOK4. Methods We have established T cell lines, expressing wild type and mutated DOK4, which will be used to perform functional tests, such as localization analysis through immunofluorescence and cytokine profiling, to check for T cell function. We have patient derived organoids, which will be used to assess changes in gut morphology using imaging techniques. We will also generate mutant zebrafish model that will be used to determine the susceptibility to colitis related to this mutation, disease progression and gut peristalsis using live imaging technology. Results Preliminary data shows variation in expression of the protein within patient derived peripheral blood mononuclear cells (PBMCs) compared to a healthy donor. Conclusions With this study, we hope to identify new therapeutic targets for patients with DOK4 mutations. Funding Agencies CIHRThe Leona M. and Harry B. Helmsley Charitable Trust


2021 ◽  
Vol 218 (8) ◽  
Author(s):  
Bryan M. Rogers ◽  
Laura Smith ◽  
Zoltan Dezso ◽  
Xu Shi ◽  
Enrico DiGiammarino ◽  
...  

As indicated by its name, V-domain Ig suppressor of T cell activation (VISTA) is thought to serve primarily as an inhibitory protein that limits immune responses. VISTA antibodies can dampen the effects of several concomitantly elicited activation signals, including TCR and TLR activation, but it is currently unclear if VISTA agonism could singly affect immune cell biology. In this study, we discovered two novel VISTA antibodies and characterized their effects on human peripheral blood mononuclear cells by scRNA/CITE-seq. Both antibodies appeared to agonize VISTA in an Fc-functional manner to elicit transcriptional and functional changes in monocytes consistent with activation. We also used pentameric VISTA to identify Syndecan-2 and several heparan sulfate proteoglycan synthesis genes as novel regulators of VISTA interactions with monocytic cells, adding further evidence of bidirectional signaling. Together, our study highlights several novel aspects of VISTA biology that have yet to be uncovered in myeloid cells and serves as a foundation for future research.


2021 ◽  
Vol 23 (1) ◽  
Author(s):  
David A. Fox ◽  
Steven K. Lundy ◽  
Michael L. Whitfield ◽  
Veronica Berrocal ◽  
Phillip Campbell ◽  
...  

Abstract Background Abnormalities in lymphocyte surface markers and functions have been described in systemic sclerosis (SSc), but conflicting results abound, and these studies often examined patients with heterogeneous disease duration, severity, clinical phenotype, and concurrent immunosuppressive agents. We studied a clinically homogeneous group of early diffuse cutaneous SSc patients not exposed to immunosuppressive drugs who were enrolled in a clinical trial and compared their immune parameters to healthy control subjects. Methods Lymphocyte subsets were enumerated by multi-parameter flow cytometry of peripheral blood mononuclear cells at baseline visit. Production of the cytokines IL-4 and IL-17 was measured by intracellular flow cytometry following T cell activation. Results SSc patients had increased percentages of CD4+ T cells but lower percentages of CD8+ T cells versus controls. The CD28-negative population was expanded in SSc, in the CD4 subset. Striking expansion of CD319+ T cells was noted among the CD4+ cells, in which they were barely detectable in healthy subjects. Frequencies of IL-4 producing cells did not differ between SSc and controls, but expansion of IL-17 producing cells was observed in SSc. A higher proportion of CD319+ cells produced cytokines, compared to other CD4+ cells. Numbers of activated T cells, regulatory T cells, and B cells were similar in SSc and control groups. Circulating follicular helper but not peripheral helper T cells were slightly expanded in SSc. Conclusion In this carefully selected group of early diffuse cutaneous SSc patients, analysis of immune cell parameters has identified abnormalities that likely reflect disease pathogenesis and that are candidate biomarkers for sub-classification and targeted treatment. The CD4+CD319+ (SLAM-F7+) cells are cytotoxic and oligoclonal, were recently shown to be a dominant T cell population in perivascular lymphocytic infiltrates in SSc skin, actively secrete cytokines, and are emerging as a target for novel treatments of SSc.


2020 ◽  
Vol 22 (1) ◽  
pp. 274
Author(s):  
Claudia Curci ◽  
Angela Picerno ◽  
Nada Chaoul ◽  
Alessandra Stasi ◽  
Giuseppe De Palma ◽  
...  

Adult Renal Stem/Progenitor Cells (ARPCs) have been recently identified in the human kidney and several studies show their active role in kidney repair processes during acute or chronic injury. However, little is known about their immunomodulatory properties and their capacity to regulate specific T cell subpopulations. We co-cultured ARPCs activated by triggering Toll-Like Receptor 2 (TLR2) with human peripheral blood mononuclear cells for 5 days and 15 days and studied their immunomodulatory capacity on T cell subpopulations. We found that activated-ARPCs were able to decrease T cell proliferation but did not affect CD8+ and CD4+ T cells. Instead, Tregs and CD3+ CD4- CD8- double-negative (DN) T cells decreased after 5 days and increased after 15 days of co-culture. In addition, we found that PAI1, MCP1, GM-CSF, and CXCL1 were significantly expressed by TLR2-activated ARPCs alone and were up-regulated in T cells co-cultured with activated ARPCs. The exogenous cocktail of cytokines was able to reproduce the immunomodulatory effects of the co-culture with activated ARPCs. These data showed that ARPCs can regulate immune response by inducing Tregs and DN T cells cell modulation, which are involved in the balance between immune tolerance and autoimmunity.


Author(s):  
Adjimon G Lokossou ◽  
Caroline Toudic ◽  
Phuong Trang Nguyen ◽  
Xavier Elisseeff ◽  
Amandine Vargas ◽  
...  

Abstract Modulation of the activation status of immune cell populations during pregnancy depends on placental villous cytotrophoblast (VCT) cells and the syncytiotrophoblast (STB). Failure in the establishment of this immunoregulatory function leads to pregnancy complications. Our laboratory has been studying Syncytin-2 (Syn-2), an endogenous retroviral protein expressed in placenta and on the surface of placental exosomes. This protein plays an important role not only in STB formation through its fusogenic properties, but also through its immunosuppressive domain (ISD). Considering that Syn-2 expression is importantly reduced in preeclamptic placentas, we were interested in addressing its possible immunoregulatory effects on T cells. Activated Jurkat T cells and peripheral blood mononuclear cells (PBMCs) were treated with monomeric or dimerized version of a control or a Syn-2 ISD peptide. Change in phosphorylation levels of ERK1/2 MAP kinases was selectively noted in Jurkat cells treated with the dimerized ISD peptide. Upon incubation with the dimerized Syn-2 ISD peptide, significant reduction in Th1 cytokine production was further demonstrated by ELISA and Human Th1/Th2 Panel Multi-Analyte Flow Assay. To determine if exosome-associated Syn-2 could also be immunosuppressive placental exosomes were incubated with activated Jurkat and PBMCs. Quantification of Th1 cytokines in the supernatants revealed severe reduction in T cell activation. Interestingly, exosomes from Syn-2-silenced VCT incubated with PBMCs were less suppressive when compared with exosome derived from VCT transfected with control small interfering RNA (siRNA). Our results suggest that Syn-2 is an important immune regulator both locally and systemically, via its association with placental exosomes.


2021 ◽  
Vol 9 (1) ◽  
pp. e001762
Author(s):  
Punit Upadhyaya ◽  
Johanna Lahdenranta ◽  
Kristen Hurov ◽  
Sailaja Battula ◽  
Rachel Dods ◽  
...  

BackgroundIn contrast to immune checkpoint inhibitors, the use of antibodies as agonists of immune costimulatory receptors as cancer therapeutics has largely failed. We sought to address this problem using a new class of modular synthetic drugs, termed tumor-targeted immune cell agonists (TICAs), based on constrained bicyclic peptides (Bicycles).MethodsPhage libraries displaying Bicycles were panned for binders against tumor necrosis factor (TNF) superfamily receptors CD137 and OX40, and tumor antigens EphA2, Nectin-4 and programmed death ligand 1. The CD137 and OX40 Bicycles were chemically conjugated to tumor antigen Bicycles with different linkers and stoichiometric ratios of binders to obtain a library of low molecular weight TICAs (MW <8 kDa). The TICAs were evaluated in a suite of in vitro and in vivo assays to characterize their pharmacology and mechanism of action.ResultsLinking Bicycles against costimulatory receptors (e.g., CD137) to Bicycles against tumor antigens (e.g., EphA2) created potent agonists that activated the receptors selectively in the presence of tumor cells expressing these antigens. An EphA2/CD137 TICA (BCY12491) efficiently costimulated human peripheral blood mononuclear cells in vitro in the presence of EphA2 expressing tumor cell lines as measured by the increased secretion of interferon γ and interleukin-2. Treatment of C57/Bl6 mice transgenic for the human CD137 extracellular domain (huCD137) bearing EphA2-expressing MC38 tumors with BCY12491 resulted in the infiltration of CD8+ T cells, elimination of tumors and generation of immunological memory. BCY12491 was cleared quickly from the circulation (plasma t1/2 in mice of 1–2 hr), yet intermittent dosing proved effective.ConclusionTumor target-dependent CD137 agonism using a novel chemical approach (TICAs) afforded elimination of tumors with only intermittent dosing suggesting potential for a wide therapeutic index in humans. This work unlocks a new path to effective cancer immunotherapy via agonism of TNF superfamily receptors.


Author(s):  
Melanie R. Neeland ◽  
Sandra Andorf ◽  
Thanh D. Dang ◽  
Vicki L. McWilliam ◽  
Kirsten P. Perrett ◽  
...  

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