This work was supported by grants to S.K. from the Japan Society for the Promotion of Science KAKENHI (JP17K16045) and the Japan Agency for Medical Research and Development (JP18cm0106335 and 19cm0106310).

Sampling was performed during routine clinical procedures. All human samples were obtained after informed consent was provided by the subjects, in accordance with the Declaration of Helsinki and with the approval of the ethical review board of the Graduate School of Medicine, Osaka University, Japan (15383 and 752).
1. Whole Blood Sample Preparation and Staining
<ol>
	<li>Collect whole blood samples into blood collection tubes containing ethylene diamine tetra-acetic acid (EDTA). 
	NOTE: Blood collection can be performed using either a regular needle or a blood lancet.</li>
	<li>Transfer 20 &#181;L of whole blood samples to 5 mL round-bottom polystyrene flow cytometry tubes. 
	NOTE: To reduce non-specific binding of cells to tubes, 1 mL of 2% fetal bovine serum (FBS) in phosphate buffered saline (PBS) is added into tubes and vortexed for 10 s before application to samples.</li>
	<li>Add 20 &#181;L of 2% FBS in PBS.</li>
	<li>Add 10 &#181;L of human-specific FcR blocking reagent. Mix well and incubate for 15 min at room temperature.</li>
	<li>Add 500 &#181;L of red blood cell lysis buffer. Mix well and incubate for 10 min at room temperature.</li>
	<li>Add 4 mL of 2% FBS in PBS and spin down cells at 400 x g (1,500 rpm) for 5 min at 4 &#176;C. Remove supernatant by aspiration.</li>
	<li>Repeat the wash and aspiration process described in step 1.6.</li>
	<li>Re-suspend cells in 100 &#181;L of 2% FBS in PBS and divide into two tubes of 50 &#181;L each.</li>
	<li>Add surface marker antibodies (Table 1). Mix well and incubate for 20 min at room temperature in the dark. 
	NOTE: When profiling the T cell immune status, the number of markers can be increased based on the flow cytometry machine quality.</li>
	<li>Wash samples 2x as described in step 1.6.</li>
	<li>Resuspend cells in 200 &#181;L of 2% FBS in PBS.</li>
</ol>
2. Flow Cytometric Analysis
<ol>
	<li>Insert tubes into the flow cytometer and acquire cells, basically following the recommended protocol9.</li>
	<li>Record 10,000 events as the lymphocyte gate (Figure 1A) and export flow data as .fcs files for analysis.</li>
	<li>Open files in the analysis software. Visualize the cells on a forward scatter (FSC) (A) vs. side scatter (SSC) (A) plot and gate lymphocytes (Figure 1A).</li>
	<li>After selecting single cells using FSC (H) vs. FSC (W) and SSC (H) vs. SSC (W) (Figure 1B) and displaying them on a CD3 vs. CD8 or CD3 vs. CD4 plot, gate the CD8 T cells and CD4 T cells, respectively (Figure 1C).</li>
	<li>After selecting the gated cells and displaying them on a PD-1 vs. human IgG4 plot, identify PD-1&#8211;blocking antibody&#8211;bound CD8 and CD4 T cells based on isotype control (Figure 1D).</li>
</ol>

<ol>
	<li>Gong, J., Chehrazi-Raffle, A., Reddi, S., Salgia, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+PD-1+and+PD-L1+inhibitors+as+a+form+of+cancer+immunotherapy:+a+comprehensive+review+of+registration+trials+and+future+considerations.">Development of PD-1 and PD-L1 inhibitors as a form of cancer immunotherapy: a comprehensive review of registration trials and future considerations.</a> Journal for ImmunoTherapy of Cancer. 6 (1), 8 (2018).</li><li>Borghaei, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nivolumab+versus+Docetaxel+in+Advanced+Nonsquamous+Non-Small-Cell+Lung+Cancer.">Nivolumab versus Docetaxel in Advanced Nonsquamous Non-Small-Cell Lung Cancer.</a> The New England Journal of Medicine. 373 (17), 1627-1639 (2015).</li><li>Brahmer, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nivolumab+versus+Docetaxel+in+Advanced+Squamous-Cell+Non-Small-Cell+Lung+Cancer.">Nivolumab versus Docetaxel in Advanced Squamous-Cell Non-Small-Cell Lung Cancer.</a> The New England Journal of Medicine. 373 (2), 123-135 (2015).</li><li>Herbst, R. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pembrolizumab+versus+docetaxel+for+previously+treated,+PD-L1-positive,+advanced+non-small-cell+lung+cancer+(KEYNOTE-010):+a+randomised+controlled+trial.">Pembrolizumab versus docetaxel for previously treated, PD-L1-positive, advanced non-small-cell lung cancer (KEYNOTE-010): a randomised controlled trial.</a> The Lancet. 387 (10027), 1540-1550 (2016).</li><li>Postow, M. A., Sidlow, R., Hellmann, M. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immune-Related+Adverse+Events+Associated+with+Immune+Checkpoint+Blockade.">Immune-Related Adverse Events Associated with Immune Checkpoint Blockade.</a> The New England Journal of Medicine. 378 (2), 158-168 (2018).</li><li>Weber, J. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Safety+Profile+of+Nivolumab+Monotherapy:+A+Pooled+Analysis+of+Patients+With+Advanced+Melanoma.">Safety Profile of Nivolumab Monotherapy: A Pooled Analysis of Patients With Advanced Melanoma.</a> Journal of Clinical Oncology. 35 (7), 785-792 (2017).</li><li>Champiat, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Management+of+immune+checkpoint+blockade+dysimmune+toxicities:+a+collaborative+position+paper.">Management of immune checkpoint blockade dysimmune toxicities: a collaborative position paper.</a> Annals of Oncology. 27 (4), 559-574 (2016).</li><li>Brahmer, J. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phase+I+study+of+single-agent+anti-programmed+death-1+(MDX-1106)+in+refractory+solid+tumors:+safety,+clinical+activity,+pharmacodynamics,+and+immunologic+correlates.">Phase I study of single-agent anti-programmed death-1 (MDX-1106) in refractory solid tumors: safety, clinical activity, pharmacodynamics, and immunologic correlates.</a> Journal of Clinical Oncology. 28 (19), 3167-3175 (2010).</li><li>Bommareddy, P. K., Lowe, D. B., Kaufman, H. L., Rabkin, S. D., Saha, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multi-parametric+flow+cytometry+staining+procedure+for+analyzing+tumor-infiltrating+immune+cells+following+oncolytic+herpes+simplex+virus+immunotherapy+in+intracranial+glioblastoma.">Multi-parametric flow cytometry staining procedure for analyzing tumor-infiltrating immune cells following oncolytic herpes simplex virus immunotherapy in intracranial glioblastoma.</a> Journal of Biological Methods. 6 (2), 112 (2019).</li><li>Osa, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clinical+implications+of+monitoring+nivolumab+immunokinetics+in+non-small+cell+lung+cancer+patients.">Clinical implications of monitoring nivolumab immunokinetics in non-small cell lung cancer patients.</a> JCI Insight. 3 (19), 59125 (2018).</li><li>Zelba, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Accurate+quantification+of+T-cells+expressing+PD-1+in+patients+on+anti-PD-1+immunotherapy.">Accurate quantification of T-cells expressing PD-1 in patients on anti-PD-1 immunotherapy.</a> Cancer Immunology, Immunotherapy. 67 (12), 1845-1851 (2018).</li><li>Simoni, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bystander+CD8(+)+T+cells+are+abundant+and+phenotypically+distinct+in+human+tumour+infiltrates.">Bystander CD8(+) T cells are abundant and phenotypically distinct in human tumour infiltrates.</a> Nature. 557 (7706), 575-579 (2018).</li><li>Chiu, H. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+a+general+method+for+quantifying+IgG-based+therapeutic+monoclonal+antibodies+in+human+plasma+using+protein+G+purification+coupled+with+a+two+internal+standard+calibration+strategy+using+LC-MS/MS.">Development of a general method for quantifying IgG-based therapeutic monoclonal antibodies in human plasma using protein G purification coupled with a two internal standard calibration strategy using LC-MS/MS.</a> Analytica Chimica Acta. 1019, 93-102 (2018).</li></ol>

The authors have nothing to disclose.

In this article, we report a method using a flow cytometer to detect PD-1&#8211;blocking antibodies bound to T cells derived from a drop of peripheral blood, which we originally developed for nivolumab detection10. Although this technique is very simple and easy to perform, two important points should be noted in order to obtain accurate results. One is that to detect PD-1 molecules, an appropriate antibody that competes with nivolumab and pembrolizumab should be used. This issue was evaluated in ...

PD-1&#8211;blocking antibodies have become the standard choice for treatment of various types of cancer, including non-small cell lung cancer (NSCLC)1,2,3,4. They show a remarkable therapeutic effect in a subset of cancer patients who have not responded to conventional cytotoxic chemotherapies. However, immune checkpoint inhibitors (ICIs), which include PD-1&#8211;blocking antibodies, can cause a unique and distinct spectrum of adverse events, termed immune-related adverse events (irAEs)5. Although irAEs can affect almost all tissues, they are most commonly observed in the gastrointestinal tract, endocrine glands, skin, and liver, and they can cause pruritus, rash, nausea, diarrhea, and thyroid disorders6,7. In general, most irAEs appear within 1 to 2 months after the initiation of ICIs. However, in some cases, they can occur later than 1 year after the beginning of treatment or even after treatment cessation6,7. They also cause various symptoms that may be difficult to discriminate from other pathologies. Thus, it can be challenging to promptly diagnose irAEs and treat them appropriately. irAEs can affect all tissues, and their onset is strongly influenced by circulating immune cells, especially T cells bound to PD-1&#8211;blocking antibodies. Therefore, a straightforward and minimally invasive method to monitor antibody-targeted T cells is important in clinical settings.
Here, we developed a simple method to assess the binding of PD-1&#8211;blocking antibodies to T cells using a drop of peripheral whole blood from cancer patients who received nivolumab or pembrolizumab. Using this approach, we were able to monitor each of the following: 1) the duration of antibody binding to T cells, 2) the occupancy of T cell PD-1 molecules by therapeutic antibodies, and 3) the activation status and immunological features of T cells. This method is a modification of a previously reported technique8. The amount of blood required is almost the same as that needed for a glucose test, and the approach does not require mononuclear cell enrichment or co-culturing with PD-1&#8211;blocking antibodies. We confirmed that this method can also be performed using frozen samples, including peripheral blood mononuclear cells (PBMCs) and cells from pleural effusion, pericardial effusion, bronchoalveolar lavage fluid, and cerebrospinal fluid, suggesting that this strategy may be useful in the context of a multicenter study. This method may facilitate the early diagnosis of irAEs, and also help to determine the appropriate immunosuppressive treatments to control their symptoms and to identify the optimal times to initiate subsequent therapies after PD-1 inhibitors.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>10X RBC Lysis Buffer (Multi-species)</td>
			<td>Thermo Fisher Scientific</td>
			<td>00-4300-54</td>
			<td>50 mL</td>
		</tr>
		<tr>
			<td>APC/Cyanine7 anti-human CD4 Antibody</td>
			<td>BioLegend</td>
			<td>300518</td>
			<td>Clone RPA-T4</td>
		</tr>
		<tr>
			<td>BD FACS Canto II Flow Cytometer</td>
			<td>BD</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Brilliant Violet 510 anti-human CD8a Antibody</td>
			<td>BioLegend</td>
			<td>301048</td>
			<td>Clone RPA-T8</td>
		</tr>
		<tr>
			<td>Dulbecco&#39;s Phosphate Buffered Saline</td>
			<td>nacalai tesque</td>
			<td>14249-95</td>
			<td>500 mL</td>
		</tr>
		<tr>
			<td>Falcon Round-Bottom Polystyrene Tubes</td>
			<td>STEMCELL Technologies</td>
			<td>352058</td>
			<td>5 mL</td>
		</tr>
		<tr>
			<td>FcR Blocking Reagent, human</td>
			<td>Miltenyi Biotec</td>
			<td>130-059-901</td>
			<td>2 mL</td>
		</tr>
		<tr>
			<td>FLOWJO</td>
			<td>BD</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Gibco Fetal Bovine Serum</td>
			<td>Thermo Fisher Scientific</td>
			<td>12676029</td>
			<td>500 mL</td>
		</tr>
		<tr>
			<td>Mouse IgG1 monoclonal - Isotype control</td>
			<td>abcam</td>
			<td>ab81200</td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse monoclonal Anti-Human IgG4 Fc</td>
			<td>abcam</td>
			<td>ab99825</td>
			<td>Clone HP6025</td>
		</tr>
		<tr>
			<td>Pacific Blue Mouse Anti-Human CD3</td>
			<td>BD</td>
			<td>558117</td>
			<td>Clone UCHT1</td>
		</tr>
		<tr>
			<td>PE-Cy7 Mouse anti-Human CD279 (PD-1)</td>
			<td>BD</td>
			<td>561272</td>
			<td>Clone EH12.1</td>
		</tr>
		<tr>
			<td>PE-Cy7 Mouse IgG1 &#954; Isotype Control</td>
			<td>BD</td>
			<td>557646</td>
			<td></td>
		</tr>
	</tbody>
</table>

monitoring pd-1-blocking antibodies bound to t cells derived from a drop of peripheral blood

Immune checkpoint inhibitors, including PD-1&#8211;blocking antibodies, have significantly improved treatment outcomes in various types of cancer. The pharmacological efficacy of these immunotherapies is long lasting, extending even beyond the discontinuation of their injections, due to persistent blood concentrations. Here we developed a simple flow cytometry assay to evaluate the T cell binding status of the PD-1&#8211;blocking antibodies nivolumab and pembrolizumab. Like a glucose test, this assay requires just a single drop of peripheral blood. Visualizing antibody binding on T cells is more reliable than measuring antibody blood concentrations. In addition, if necessary, we can potentially analyze many distinctive immune-related markers on T cells bound to PD-1&#8211;blocking antibodies. Thus, this is a simple and minimally invasive strategy to analyze the pharmacological effect of PD-1&#8211;blocking antibodies in cancer patients.

The gating strategy and flow cytometry analysis (Figure 1) can detect PD-1&#8211;blocking antibody binding to T cells obtained from a drop of NSCLC patient peripheral blood. Before PD-1&#8211;blocking antibody is administered, no human IgG4-positive CD8 or CD4 T cells are present, and PD-1 expression can be confirmed by a PD-1&#8211;detecting antibody (EH12.1) (Figure 2A). After nivolumab or pembrolizumab administration, IgG4 (nivolumab, pembrol...

Watch this Scientific Journal Video about Monitoring PD-1-Blocking Antibodies Bound to T Cells Derived from a Drop of Peripheral Blood at JoVE.com

Monitoring PD-1-Blocking Antibodies Bound to T Cells Derived from a Drop of Peripheral Blood

We developed a simple flow cytometry assay for evaluating the binding of PD-1&#8211;blocking antibodies to T cells, requiring only a drop of peripheral blood from cancer patients.

Immune checkpoint inhibitors, including PD-1&#8211;blocking antibodies, have significantly improved treatment outcomes in various types of cancer. The ...

monitoring-pd-1-blocking-antibodies-bound-to-t-cells-derived-from

Universidad de Cartagena UDEC

Research

JoVE Journal

Medicine

5.6K Views.  Osaka University Graduate School of Medicine. We developed a simple flow cytometry assay for evaluating the binding of PD-1–blocking antibodies to T cells, requiring only a drop of peripheral blood from cancer patients.

Video: Monitoring PD-1-Blocking Antibodies Bound to T Cells Derived from a Drop of Peripheral Blood

Sequencing of Bacterial Microflora in Peripheral Blood: our Experience with HIV-infected Patients

The healthy gastrointestinal tract is physiologically colonized by a large variety of commensal microbes that influence the development 
	of the humoral and cellular mucosal immune system1,2. 
 Microbiota is shielded from the immune system via a strong mucosal barrier. Infections and antibiotics are known to alter both the normal 
	gastrointestinal tract barrier and the composition of resident bacteria, which may result in possible immune abnormalities3.
HIV causes a breach in the gastrointestinal barrier with progressive failure of mucosal immunity and leakage into the systemic circulation of bacterial bioproducts, such as lipopolysaccharide and 
	bacterial DNA fragments, which contribute to systemic immune activation4-7. Microbial translocation is implicated in HIV/AIDS immunopathogenesis and response to therapy 4,8.
We aimed to characterise the composition of bacteria translocating in peripheral blood of HIV-infected patients. To pursue our aim we set up a PCR reaction for the panbacteric 16S ribosomial gene 
	followed by a sequencing analysis.
Briefly, whole blood from both HIV-infected and healthy subjects is used. Given that healthy individuals present normal intestinal homeostasis no translocation of microflora is expected in 
	these patients. Following whole blood collection by venipuncture and plasma separation, DNA is extracted from plasma and used to perform a broad range PCR reaction for the panbacteric 
	16S ribosomial gene9. Following PCR product purification, cloning and sequencing analyses are performed.

Our experiment will show how to perform a sequencing analysis of bacterial species translocating in peripheral blood of HIV positive patients.

The healthy gastrointestinal tract is physiologically colonized by a large variety of commensal microbes that influence the development 
	of the humoral ...

Rapid Point-of-Care Assay of Enoxaparin Anticoagulant Efficacy in Whole Blood

There is the need for a clinical assay to determine the extent to which a patient's blood is effectively anticoagulated by the low-molecular-weight-heparin (LMWH), enoxaparin. There are also urgent clinical situations where it would be important if this could be determined rapidly. The present assay is designed to accomplish this. We only assayed human blood samples that were spiked with known concentrations of enoxaparin. The essential feature of the present assay is the quantification of the efficacy of enoxaparin in a patient's blood sample by degrading it to complete inactivity with heparinase. Two blood samples were drawn into Vacutainer tubes (Becton-Dickenson; Franklin Lakes, NJ) that were spiked with enoxaparin; one sample was digested with heparinase for 5 min at 37 &deg;C, the other sample represented the patient's baseline anticoagulated status. The percent shortening of clotting time in the heparinase-treated sample, as compared to the baseline state, yielded the anticoagulant contribution of enoxaparin. We used the portable, battery operated Hemochron 801 apparatus for measurements of clotting times (International Technidyne Corp., Edison, NJ). The apparatus has 2 thermostatically controlled (37 &deg;C) assay tube wells. We conducted the assays in two types of assay cartridges that are available from the manufacturer of the instrument. One cartridge was modified to increase its sensitivity. We removed the kaolin from the FTK-ACT cartridge by extensive rinsing with distilled water, leaving only the glass surface of the tube, and perhaps the detection magnet, as activators. We called this our minimally activated assay (MAA). The use of a minimally activated assay has been studied by us and others. 2-4 The second cartridge that was studied was an activated partial thromboplastin time (aPTT) assay (A104). This was used as supplied from the manufacturer. The thermostated wells of the instrument were used for both the heparinase digestion and coagulation assays. The assay can be completed within 10 min. The MAA assay showed robust changes in clotting time after heparinase digestion of enoxaparin over a typical clinical concentration range. At 0.2 anti-Xa I.U. of enoxaparin per ml of blood sample, heparinase digestion caused an average decrease of 9.8% (20.4 sec) in clotting time; at 1.0 I.U. per ml of enoxaparin there was a 41.4% decrease (148.8 sec). This report only presents the experimental application of the assay; its value in a clinical setting must still be established.

Demonstration of a rapid quantitative assay of the inhibition of blood coagulation by the low-molecular-weight-heparin, enoxaparin. The contribution of enoxaparin is assessed by removing its influence through digestion with heparinase. A fuller description of the assay is detailed in our published paper.1 The assay still requires clinical confirmation.

There is the need for a clinical assay to determine the extent to which a patient's blood is effectively anticoagulated by the ...

Repair of a Critical-sized Calvarial Defect Model Using Adipose-derived Stromal Cells Harvested from Lipoaspirate

Craniofacial skeletal repair and regeneration offers the promise of de novo tissue formation through a cell-based approach utilizing stem cells. Adipose-derived stromal cells (ASCs) have proven to be an abundant source of multipotent stem cells capable of undergoing osteogenic, chondrogenic, adipogenic, and myogenic differentiation. Many studies have explored the osteogenic potential of these cells in vivo with the use of various scaffolding biomaterials for cellular delivery. It has been demonstrated that by utilizing an osteoconductive, hydroxyapatite-coated poly(lactic-co-glycolic acid) (HA-PLGA) scaffold seeded with ASCs, a critical-sized calvarial defect, a defect that is defined by its inability to undergo spontaneous healing over the lifetime of the animal, can be effectively show robust osseous regeneration. This in vivo model demonstrates the basis of translational approaches aimed to regenerate the bone tissue - the cellular component and biological matrix. This method serves as a model for the ultimate clinical application of a progenitor cell towards the repair of a specific tissue defect.

This protocol describes the isolation of adipose-derived stromal cells from lipoaspirate and the creation of a 4 mm critical-sized calvarial defect to evaluate skeletal regeneration.

Craniofacial skeletal repair and regeneration offers the promise of de novo tissue formation through a cell-based approach utilizing stem cells. ...

High Throughput Sequential ELISA for Validation of Biomarkers of Acute Graft-Versus-Host Disease

Unbiased discovery proteomics strategies have the potential to identify large numbers of novel biomarkers that can improve diagnostic and prognostic testing in a clinical setting and may help guide therapeutic interventions. When large numbers of candidate proteins are identified, it may be difficult to validate candidate biomarkers in a timely and efficient fashion from patient plasma samples that are event-driven, of finite volume and irreplaceable, such as at the onset of acute graft-versus-host disease (GVHD), a potentially life-threatening complication of allogeneic hematopoietic stem cell transplantation (HSCT).
Here we describe the process of performing commercially available ELISAs for six validated GVHD proteins: IL-2R&alpha;5, TNFR16, HGF7, IL-88, elafin2, and REG3&alpha;3 (also known as PAP1) in a sequential fashion to minimize freeze-thaw cycles, thawed plasma time and plasma usage. For this procedure we perform the ELISAs in sequential order as determined by sample dilution factor as established in our laboratory using manufacturer ELISA kits and protocols with minor adjustments to facilitate optimal sequential ELISA performance. The resulting plasma biomarker concentrations can then be compiled and analyzed for significant findings within a patient cohort. While these biomarkers are currently for research purposes only, their incorporation into clinical care is currently being investigated in clinical trials.
This technique can be applied to perform ELISAs for multiple proteins/cytokines of interest on the same sample(s) provided the samples do not need to be mixed with other reagents. If ELISA kits do not come with pre-coated plates, 96-well half-well plates or 384-well plates can be used to further minimize use of samples/reagents.

High throughput validation of multiple candidate biomarkers can be performed by sequential ELISA in order to minimize freeze/thaw cycles and use of precious plasma samples. Here, we demonstrate how to sequentially perform ELISAs for six different validated plasma biomarkers1-3 of graft-versus-host disease (GVHD)4 on the same plasma sample.

Unbiased discovery proteomics strategies have  the potential to identify large numbers of novel biomarkers that can improve  diagnostic and prognostic ...

Isolation, Characterization and Comparative Differentiation of Human Dental Pulp Stem Cells Derived from Permanent Teeth by Using Two Different Methods

Developing wisdom teeth are easy-accessible source of stem cells during the adulthood which could be obtained by routine orthodontic treatments. Human pulp-derived stem cells (hDPSCs) possess high proliferation potential with multi-lineage differentiation capacity compare to the ordinary source of adult stem cells1-8; therefore, hDPSCs could be the good candidates for autologous transplantation in tissue engineering and regenerative medicine. Along with these benefits, possessing the mesenchymal stem cells (MSC) features, such as immunolodulatory effect, make hDPSCs more valuable, even in the case of allograft transplantation6,9,10. Therefore, the primary step for using this source of stem cells is to select the best protocol for isolating hDPSCs from pulp tissue. In order to achieve this goal, it is crucial to investigate the effect of various isolation conditions on different cellular behaviors, such as their common surface markers &amp; also their differentiation capacity.
Thus, here we separate human pulp tissue from impacted third molar teeth, and then used both existing protocols based on literature, for isolating hDPSCs,11-13 i.e. enzymatic dissociation of pulp tissue (DPSC-ED) or outgrowth from tissue explants (DPSC-OG). In this regards, we tried to facilitate the isolation methods by using dental diamond disk. Then, these cells characterized in terms of stromal-associated Markers (CD73, CD90, CD105 &amp; CD44), hematopoietic/endothelial Markers (CD34, CD45 &amp; CD11b), perivascular marker, like CD146 and also STRO-1. Afterwards, these two protocols were compared based on the differentiation potency into odontoblasts by both quantitative polymerase chain reaction (QPCR) &amp; Alizarin Red Staining. QPCR were used for the assessment of the expression of the mineralization-related genes (alkaline phosphatase; ALP, matrix extracellular phosphoglycoprotein; MEPE &amp; dentin sialophosphoprotein; DSPP).14

The method described isolation and characterization of human Dental Pulp Stem Cells (hDPSCs) by using either enzymatic dissociation of pulp (DPSC-ED) or direct outgrowth of stem cells from pulp tissue explants (DPSC-OG). Then followed by in vitro comparative differentiation of both types of hDPSCs into odontoblasts.

Developing wisdom teeth are easy-accessible source of stem cells during the adulthood which could be obtained by routine orthodontic treatments. Human ...

Time-lapse Imaging of Primary Preneoplastic Mammary Epithelial Cells Derived from Genetically Engineered Mouse Models of Breast Cancer

Time-lapse imaging can be used to compare behavior of cultured primary preneoplastic mammary epithelial cells derived from different genetically engineered mouse models of breast cancer. For example, time between cell divisions (cell lifetimes), apoptotic cell numbers, evolution of morphological changes, and mechanism of colony formation can be quantified and compared in cells carrying specific genetic lesions. Primary mammary epithelial cell cultures are generated from mammary glands without palpable tumor. Glands are carefully resected with clear separation from adjacent muscle, lymph nodes are removed, and single-cell suspensions of enriched mammary epithelial cells are generated by mincing mammary tissue followed by enzymatic dissociation and filtration. Single-cell suspensions are plated and placed directly under a microscope within an incubator chamber for live-cell imaging. Sixteen 650 &mu;m x 700 &mu;m fields in a 4x4 configuration from each well of a 6-well plate are imaged every 15 min for 5 days. Time-lapse images are examined directly to measure cellular behaviors that can include mechanism and frequency of cell colony formation within the first 24 hr of plating the cells (aggregation versus cell proliferation), incidence of apoptosis, and phasing of morphological changes. Single-cell tracking is used to generate cell fate maps for measurement of individual cell lifetimes and investigation of cell division patterns. Quantitative data are statistically analyzed to assess for significant differences in behavior correlated with specific genetic lesions.

Time-lapse imaging is used to assess behavior of primary preneoplastic mammary epithelial cells derived from genetically engineered mouse models of breast cancer risk to determine if there are correlations between specific behavioral parameters and distinct genetic lesions.

Time-lapse  imaging can be used to compare behavior of cultured primary preneoplastic  mammary epithelial cells derived from different genetically ...

Orthotopic Implantation and Peripheral Immune Cell Monitoring in the II-45 Syngeneic Rat Mesothelioma Model

The enormous upsurge of interest in immune-based treatments for cancer such as vaccines and immune checkpoint inhibitors, and increased understanding of the role of the tumor microenvironment in treatment response, collectively point to the need for immune-competent orthotopic models for pre-clinical testing of these new therapies. This paper demonstrates how to establish an orthotopic immune-competent rat model of pleural malignant mesothelioma. Monitoring disease progression in orthotopic models is confounded by the internal location of the tumors. To longitudinally monitor disease progression and its effect on circulating immune cells in this and other rat models of cancer, a single tube flow cytometry assay requiring only 25 &#181;l whole blood is described. This provides accurate quantification of seven immune parameters: total lymphocytes, monocytes and neutrophils, as well as the T-cell subsets CD4 and CD8, B-cells and Natural Killer cells. Different subsets of these parameters are useful in different circumstances and models, with the neutrophil to lymphocyte ratio having the greatest utility for monitoring disease progression in the mesothelioma model. Analyzing circulating immune cell levels using this single tube method may also assist in monitoring the response to immune-based treatments and understanding the underlying mechanisms leading to success or failure of treatment.

The generation of an orthotopic rat model of pleural malignant mesothelioma by implantation of II-45 mesothelioma cells into the pleural cavity of immune competent rats is presented. A flow cytometric method to analyze seven immune cell subsets in these animals from a 25 &#181;l&#160;blood sample is also described.

The enormous upsurge of interest in immune-based treatments for cancer such as vaccines and immune checkpoint inhibitors, and increased understanding of ...

Generation of Prostate Cancer Patient Derived Xenograft Models from Circulating Tumor Cells

Patient derived xenograft (PDX) models are gaining popularity in cancer research and are used for preclinical drug evaluation, biomarker identification, biologic studies, and personalized medicine strategies. Circulating tumor cells (CTC) play a critical role in tumor metastasis and have been isolated from patients with several tumor types. Recently, CTCs have been used to generate PDX experimental models of breast and prostate cancer. This manuscript details the method for the generation of prostate cancer PDX models from CTCs developed by our group. Advantages of this method over conventional PDX models include independence from surgical sample collection and generating experimental models at various disease stages. Density gradient centrifugation followed by red blood cell lysis and flow cytometry depletion of CD45 positive mononuclear cells is used to enrich CTCs from peripheral blood samples collected from patients with metastatic disease. The CTCs are then injected into immunocompromised mice; subsequently generated xenografts can be used for functional studies or harvested for molecular characterization. The primary limitation of this method is the negative selection method used for CTC enrichment. Despite this limitation, the generation of PDX models from CTCs provides a novel experimental model to be applied to prostate cancer research.

This manuscript details a method used to generate prostate cancer patient derived xenografts (PDXs) from circulating tumor cells (CTCs). The generation of PDX models from CTCs provides an alternative experimental model to study prostate cancer; the most commonly diagnosed tumor and a frequent cause of death from cancer in men.

Patient derived xenograft (PDX) models are gaining popularity in cancer research and are used for preclinical drug evaluation, biomarker identification, ...

Microelectrode Impalement Method to Record Membrane Potential from a Cannulated Middle Cerebral Artery

Membrane potential (Vm) of vascular smooth muscle cells determines vessel tone and thus blood flow to an organ. Changes in the expression and function of ion channels and electrogenic pumps that regulate Vm in disease conditions could potentially alter Vm, vascular tone, and blood flow. Thus, a basic understanding of electrophysiology and the methods necessary to accurately record Vm in healthy and diseased states are essential. This method will allow modulating Vm using different pharmacological agents to restore Vm. Although there are several methods, each with its advantages and disadvantages, this article provides protocols to record Vm from cannulated resistance vessels such as the middle cerebral artery using the microelectrode impalement method. Middle cerebral arteries are allowed to gain myogenic tone in a myograph chamber, and the vessel wall is impaled using high resistance microelectrodes. The Vm signal is collected through an electrometer, digitized, and analyzed. This method provides an accurate reading of the Vm of a vessel wall without damaging the cells and without changing the membrane resistance.

The primary goal of this article is to provide details of how to record membrane potential (Vm) from the middle cerebral artery using the microelectrode impalement method. The cannulated middle cerebral artery is equilibrated to gain myogenic tone, and the vessel wall is impaled using high resistance microelectrodes.

Membrane potential (Vm) of vascular smooth muscle cells determines vessel tone and thus blood flow to an organ. Changes in the expression and function of ...

Isolation of Adipose Derived Regenerative Cells for the Treatment of Erectile Dysfunction Following Radical Prostatectomy

Stem cells are used in many research areas within regenerative medicine in part because these treatments can be curative rather than symptomatic. Stem cells can be obtained from different tissues and several methods for isolation have been described. The presented method for the isolation of adipose-derived regenerative cells (ADRCs) can be used within many therapeutic areas because the method is a general procedure and, therefore, not limited to erectile dysfunction (ED) therapy. ED is a common and serious side effect to radical prostatectomy (RP) since ED often is not well treated with conventional therapy. Using ADRC&#8217;s as treatment for ED has attracted great interest due to the initial positive results after a single injection of cells into the corpora cavernosum. The method used for the isolation of ADRC&#8217;s is a simple, automated process, that is reproducible and ensures a uniform product. Furthermore, the sterility of the isolated product is ensured because the entire process takes place in a closed system. It is important to minimize the risk of contamination and infection since the stem cells are used for injection in humans. The whole procedure can be done within 2.5-3.5 hours and does not require a classified laboratory which eliminates the need for shipping tissue to an off-site. However, the procedure has some limitations since the minimum amount of drained lipoaspirate for the isolation device to function is 100 g.

Precise disclosure of methods and protocols is crucial for large scale uptake of stem cell therapies. Here, we present a protocol to isolate adipose-derived regenerative cells, used for a single intracavernous injection as treatment of erectile dysfunction (ED) following radical prostatectomy (RP).

Stem cells are used in many research areas within regenerative medicine in part because these treatments can be curative rather than symptomatic. Stem ...