A Detailed Phenotypic Analysis Using Six Color Flow Cytometry of Lymphocyte Subsets Mobilized with AMD3100 Compared to G-CSF.

Abstract AMD3100 (AMD) is a bicyclam compound that rapidly mobilizes hematopoietic progenitor cells into circulation by inhibiting stromal cell derived factor-1 binding to its cognate receptor CXCR4 present on CD34+ cells. Preliminary data in healthy donors and cancer patients show large numbers of CD34+ cells are mobilized following a single injection of AMD3100. To determine whether AMD3100 mobilized cells would be suitable for allografting, we performed a detailed phenotypic analysis using 6 color flow cytometry (CYAN Cytometer MLE) of lymphocyte subsets mobilized following the administration of AMD3100, given as a single 240mcg/kg injection either alone (n=4) or in combination with G-CSF (n=2: G-CSF 10 mcg/kg/day x 5: AMD3100 given on day 4). Baseline peripheral blood (PB) was obtained immediately prior to mobilization; in recipients who received both agents, blood was analyzed 4 days following G-CSF administration as well as 12 hours following administration of AMD3100 and a 5th dose of G-CSF. AMD3100 alone significantly increased from baseline the PB WBC count (2.8 fold), Absolute lymphocyte count (ALC: 2.5 fold), absolute monocyte count (AMC: 3.4 fold), and absolute neutrophil count (ANC: 2.8 fold). Subset analysis showed AMD3100 preferentially increased from baseline PB CD34+ progenitor counts (5.8 fold), followed by CD19+ B-cells (3.7 fold), CD14+ monocytes (3.4 fold), CD8+ T-cells (2.5 fold), CD4+ T-cells (1.8 fold), with a smaller increase in CD3−/CD16+ or CD56+ NK cell counts (1.6 fold). There was no change from baseline in the % of CD4+ or CD8+ T-cell expressing CD45RA, CD45RO, or CD56, CD57, CD27, CD71 or HLA-DR. In contrast, there was a decline compared to baseline in the mean percentage of CD3+/CD4+ T-cells expressing CD25 (5.5% vs 14.8%), CD62L (12.1% vs 41.1%), CCR7 (2.1% vs 10.5%) and CXCR4 (0.5% vs 40.9%) after AMD3100 administration; similar declines in expression of the same 4 surface markers were also observed in CD3+/CD8+ T-cells. A synergistic effect on the mobilization of CD34+ progenitors, CD19+ B cells, CD3+ T-cells and CD14+ monocytes occurred when AMD3100 was combined with G-CSF (Figure). In those receiving both AMD3100 and G-CSF, a fall in the % of T-cells expressing CCR7 and CXCR4 occurred 12 hours after the administration of AMD3100 compared to PB collected after 4 days of G-CSF; no other differences in the expression of a variety activation and/or adhesion molecules on T-cell subsets were observed. Whether differences in lymphocyte subsets mobilized with AMD3100 alone or in combination with G-CSF will impact immune reconstitution or other either immune sequela (i.e. GVHD, graft-vs-tumor) associated with allogeneic HCT is currently being assessed in an animal model of allogeneic transplantation.

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Tigit, CD226 and PD-L1/PD-1 Are Highly Expressed By Marrow-Infiltrating T Cells in Patients with Multiple Myeloma

Blood ◽

10.1182/blood.v128.22.2102.2102 ◽

2016 ◽

Vol 128 (22) ◽

pp. 2102-2102 ◽

Cited By ~ 5

Author(s):

Mahesh Yadav ◽

Cherie Green ◽

Connie Ma ◽

Alberto Robert ◽

Andrew Glibicky ◽

...

Keyword(s):

Multiple Myeloma ◽

Bone Marrow ◽

Flow Cytometry ◽

T Cells ◽

T Cell ◽

Nk Cells ◽

Cd8 T Cells ◽

Cd4 T Cells ◽

Plasma Cells ◽

Color Flow

Abstract Introduction:TIGIT (T-cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif [ITIM] domain) is an inhibitory immunoreceptor expressed by T and natural killer (NK) cells that is an important regulator of anti-tumor and anti-viral immunity. TIGIT shares its high-affinity ligand PVR (CD155) with the activating receptor CD226 (DNAM-1). We have recently shown that TIGIT blockade, together with PD-L1/PD-1 blockade, provides robust efficacy in syngeneic tumor and chronic viral infection models. Importantly, CD226 blockade abrogates the benefit of TIGIT blockade, suggesting additional benefit of TIGIT blockade through elaboration of CD226-mediated anti-tumor immunity, analogous to CTLA-4/CD28 regulation of T-cell immunity. Whether TIGIT and CD226 are expressed in patients with multiple myeloma (MM) and how TIGIT expression relates to PD-L1/PD-1 expression is unknown. Here we evaluate expression of TIGIT, CD226, PD-1 and PD-L1 in patients with MM to inform novel immunotherapy combinations. Methods:We performed multi-color flow cytometry (n = 25 patients), and multiplex qRT-PCR (n = 7) on bone marrow specimens from patients with MM to assess expression of TIGIT, CD226, PD-1, and PD-L1 on tumor and immune cells. Cells were stained with fluorescently conjugated monoclonal antibodies to label T cells (CD3, CD4, CD8), NK cells (CD56, CD3), plasma cells (CD38, CD45, CD319, CD56), inhibitory/activating receptors (PD-1, TIGIT, PD-L1, CD226), and an amine-reactive viability dye (7-AAD). Stained and fixed cells were analyzed by flow cytometry using BD FACSCanto™ and BD LSRFortessa™. Results:TIGIT, CD226 and PD-L1/PD-1 were detectable by flow cytometry in all patients with MM who were tested, with some overlapping and distinct expression patterns. TIGIT was commonly expressed by marrow-infiltrating CD8+ T cells (median, 65% of cells), CD4+ T cells (median, 12%) and NK cells. In contrast, CD226 was more commonly expressed by marrow-infiltrating CD4+ T cells (median, 74%) compared with CD8+ T cells (median, 38%). PD-1 was expressed by marrow-infiltrating CD8+ T cells (median 38%) and CD4+ T cells (median, 16%). TIGIT was co-expressed with PD-1 on CD8+ T cells (67%-97% TIGIT+ among PD-1+), although many PD-1-negative CD8+ T cells also expressed TIGIT (39%-78% of PD-1-negative). PD-L1 was also expressed by CD8+ (median, 23%) and CD4+ (median, 8%) T cells in addition to MM plasma cells (median, 95%), albeit with significantly lower intensity on T cells compared with plasma cells. The expression of TIGIT and PD-L1 mRNA was highly correlated (R2 = 0.80). Analysis of PVR expression will also be presented. Conclusions: TIGIT, CD226, PD-1, and PD-L1 were commonly expressed in MM bone marrow, but with different patterns. Among CD8+ T cells, the frequency of TIGIT+ T cells was almost twice that of PD-1+ T cells, whereas the majority of CD4+ T cells expressed CD226. TIGIT blockade may complement anti-PD-L1/PD-1 immunotherapy by activating distinct T-cell/NK-cell subsets with synergistic clinical benefit. These results provide new insight into the immune microenvironment of MM and rationale for targeting both the PD-L1/PD-1 interaction and TIGIT in MM. Disclosures Yadav: Genentech, Inc.: Employment. Green:Genentech, Inc.: Employment. Ma:Genentech, Inc.: Employment. Robert:Genentech, Inc.: Employment. Glibicky:Makro Technologies Inc.: Employment; Genentech, Inc.: Consultancy. Nakamura:Genentech, Inc.: Employment. Sumiyoshi:Genentech, Inc.: Employment. Meng:Genentech, Inc.: Employment, Equity Ownership. Chu:Genentech Inc.: Employment. Wu:Genentech: Employment. Byon:Genentech, Inc.: Employment. Woodard:Genentech, Inc.: Employment. Adamkewicz:Genentech, Inc.: Employment. Grogan:Genentech, Inc.: Employment. Venstrom:Roche-Genentech: Employment.

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PD-1+ T Cell Subsets in Follicular Lymphoma Tumor Microenvironment and Their Implications for Prognosis and Therapy

Blood ◽

10.1182/blood.v118.21.2648.2648 ◽

2011 ◽

Vol 118 (21) ◽

pp. 2648-2648

Author(s):

Fuliang Chu ◽

Wencai Ma ◽

Tomohide Yamazaki ◽

Myriam Foglietta ◽

Durga Nattama ◽

...

Keyword(s):

Flow Cytometry ◽

T Cells ◽

T Cell ◽

Follicular Lymphoma ◽

Cd8 T Cells ◽

Cd4 T Cells ◽

T Cell Subsets ◽

Prognostic Impact ◽

T Cell Exhaustion ◽

Cell Exhaustion

Abstract Abstract 2648 Background: Programmed death (PD)-1, a coinhibitory receptor expressed by effector T cells (Teffs) is highly expressed on intratumoral T cells (mean 61%, range 34–86% for CD4+ T cells and mean 44%, range 31–69% for CD8+ T cells) in follicular lymphoma (FL), a finding associated with impaired ability to recognize autologous tumor (Nattamai et al, ASH 2007). Hence, PD-1 expression would be expected to confer an unfavorable prognosis in FL. However, correlation of PD-1 with clinical outcome in FL has been inconsistent with two studies showing favorable (Carreras et al, J Clin Oncol 2009; Wahlin et al, Clin Cancer Res 2010) and one study showing unfavorable (Richendollar et al, Hum Pathol 2011) outcome. While differences in method of analysis and type of treatment may explain the disparate results, a more complex model may be necessary to understand the prognostic impact of PD-1 in FL as PD-1 is expressed not only on antitumor Teffs but also on protumor follicular helper T cells (Tfh) and regulatory T cells (Tregs). Methods: To determine the nature of PD-1+ T cells in FL we performed comprehensive genomic and immunologic studies. By flow cytometry, we observed that the intratumoral CD4+ T cells in FL may be categorized into 3 subsets based on PD-1 expression - PD-1 high (PD-1hi), intermediate (PD-1int), and low (PD-1lo). The intratumoral CD8+ T cells consisted of PD-1int and PD-1lo subsets. The 3 CD4+ T cell subsets were FACSorted from FL tumors (n=3) and whole genome gene expression profiling (GEP) was performed. T cell subsets sorted similarly from tonsils served as controls for reactive follicular hyperplasia (FH) (n=3). Differentially expressed genes in GEP studies were confirmed at the mRNA level by real-time PCR (n=5) and at the protein level by flow cytometry when antibodies were available (n=5–10). Results: Our results suggested that CD4+PD-1hi T cells are Tfh cells (CXCR5hiBcl6hi ICOShiCD40LhiSAPhiPRDM1loIL-4hiIL-21hi); the CD4+PD-1int T cells consisted of a mixture of activated Teffs (CD45RO+CD45RA−) including Th1 (Tbet+IFNg+), Th2 (IL-10+), and Th17 cells (RORc+IL-17+), and Tregs (Foxp3+CD25hiCD127lo); and the CD4+PD-1lo T cells consisted of a mixture of activated Teffs (CD45RO+CD45RA− but IFNg−IL-4−IL-10−IL-17−), Tregs, and naïve T cells (CD45RO−CD45RA+CCR7+). Although these subsets were present in both FL and FH, there were important differences. IL-4 expression was significantly higher in Tfh in FL vs. FH and may play a role in the pathogenesis of FL. IL-17 expression was low and expression of coinhibitory molecules BTLA and CD200 was high in CD4+PD-1int T cells in FL vs. FH. BTLA and CD200 were also increased in CD8+PD-1int T cells in FL vs. FH. However, other coinhibitory molecules (LAG-3, Tim-3, CD160, CTLA-4, CD244, KLRG1) were not significantly different between FL and FH. CD4+PD-1int T cells also had higher expression of BATF, a transcription factor associated with T cell exhaustion in FL vs. FH. Together, these results suggest that the CD4+PD-1int T cells in FL may be in a state of T cell exhaustion whereas the CD4+PD-1int T cells in FH may represent recently activated Teffs. Consistent with this, blocking PD-1 with anti-PD-1 blocking antibody significantly enhanced proliferation and the production of Th1 (IFNg, TNFa) but not Th2 (IL-4, IL-5, IL-10, IL-13) cytokines by intratumoral CD4+ and CD8+ T cells in response to stimulation with autologous FL tumor cells (n=3). As expected, Tregs were increased in number in FL vs. FH and were present in the PD-1int and PD-1lo T cell subsets. We found 74% (range 40–97%) of FL Tregs expressed PD-1. Among the CD4+PD-1lo and CD8+PD-1lo T cells, there were more activated Teffs and fewer naïve T cells in FL vs. FH. Conclusions: Our results suggest that the PD-1+ T cells in FL are comprised of a mixture of antitumor Teffs and protumor Tfh and Tregs. The prognostic impact of PD-1+ T cells in FL may dependent on the relative frequency of these subsets as ligation of PD-1 may produce favorable (inhibition of protumor Tfh and Tregs) or unfavorable (inhibition of antitumor Teffs) outcomes by inhibiting or promoting tumor growth, respectively. Conversely, our results imply that agents that block PD-1/PD-ligand pathway may have the opposite effect on these T cell subsets and enumeration of the intratumoral PD-1+ T cell subsets may serve as biomarker to predict response to these agents in FL and possibly other B-cell malignancies. Disclosures: Dong: GSK: Consultancy; Genentech: Honoraria; Tempero: Consultancy; Ono: Consultancy; AnaptysBio: Consultancy. Neelapu:Cure Tech Ltd: Research Funding.

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Targeting The T Cell Component Of The Tumour Microenvironment In Chronic Lymphocytic Leukaemia; A Potential Therapeutic Strategy

Blood ◽

10.1182/blood.v122.21.4147.4147 ◽

2013 ◽

Vol 122 (21) ◽

pp. 4147-4147

Author(s):

Kirsty M Cuthill ◽

Andrea Gail Sherman Buggins ◽

Pj Chana ◽

Stephen Devereux

Keyword(s):

Flow Cytometry ◽

T Cells ◽

T Cell ◽

B Cells ◽

T Cell Activation ◽

Cd4 T Cells ◽

Cell Activation ◽

Lymphocytic Leukaemia ◽

Nuclear Translocation ◽

Tumour Microenvironment

Abstract It has recently become clear that B cell receptor (BCR) activation plays an important role in the pathogenesis of chronic lymphocytic leukaemia (CLL); a fact that is underlined by the marked efficacy of drugs that inhibit components of this pathway. Although the underlying mechanisms remain unclear, CLL BCRs have been shown to recognize a variety of autoantigens and there is evidence of ongoing activation of a number of downstream signaling molecules including Syk, Erk, Akt and the NFkB and NFAT family of transcription factors. In addition to BCR activation, it is thought that signals from other cells in the tumour microenvironment such as T cells, the vascular endothelium and other stromal cells may also play a role in promoting the growth of the disease. In the present study we chose to revisit the effects of ciclosporin (CsA), a calcineurin antagonist with effects on antigen receptor signaling, in CLL. When this agent is used to treat the autoimmune complications of CLL, concurrent responses in the underlying disease have been noted in about 20% of patients, although the underlying mechanism has not been thoroughly investigated. Since CsA primarily inhibits T cell activation we hypothesized that its effects in CLL might be due to a reduction in T cell mediated co-stimulation in the lymph nodes. We therefore investigated the effect of CsA on the activation of CLL B and T cells using conventional and multispectral imaging flow cytometry to measure the expression of activation markers and the nuclear translocation of NFAT and NFKB family transcription factors. Cells were collected from eight unselected patients with a confirmed diagnosis of CLL for each study. T and B cells were purified by negative immunomagnetic selection and activated by incubation with phorbol ester and ionomycin (PMA/I) or CD40L transfected fibroblasts in the presence of absence of CsA. The activation of CD4+ T cells and CD19+ CLL cells was assessed by staining for CD69/interferon gamma (IFNΥ) and CD69/CD25 respectively. Nuclear translocation of NFATc2 and NFKB p65 was measured by image flow cytometry (Amnis Imagestream). Leukaemia and Lymphoma Research provided the funding for this study. NFkB(p65) translocation at 30 minutes was inhibited by a mean of 22.5% (p=0.0003) in activated CLL CD4+ T cells treated with CsA compared to those treated with vehicle control (VC). Similarly, in the presence of CsA, NFAT-c2 translocation was inhibited by a mean of 24.3% (p=0.008) at 10 minutes in CLL CD4+ T cells compared to those treated with VC. NFkB(p65) translocation was not inhibited (mean of differences=0.63%, p=0.645) and NFAT-c2 translocation was minimally inhibited (mean of differences = -4%, p = 0.007) in activated CLL B Cells treated with CsA. The proportion of activated CLL CD4+ T cells expressing both CD69 and IFNΥ was reduced by 13.2% (p=0.003) in the presence of CsA whereas there was no inhibition of CD25(-1.5, p=0.16) and CD69(-1.4, p=0.5) expression in activated CLL B cells treated with CsA. In summary, CsA had a profound effect on CD4+ T cell activation in patients with CLL, as demonstrated by the reduction in NFkB (p65), NFAT-c2 nuclear translocation and CD69/IFNΥ expressing cells. In contrast, there was a minimal effect on NFAT-c2 translocation in activated CLL B cells and no impact on NFkB (p65) translocation or the expression of CD25 and CD69. These findings suggest that the previously documented activity of CsA in CLL is not due to a direct effect on the tumour but is instead indirect and mediated through inhibition of other microenvironment derived signals such as those provided by activated CD4+ T cells. Since it is likely that these co-stimulatory effects act in concert other signals, such as those induced by BCR activation, reexamination of CsA and similar agents in CLL would thus seem warranted. Disclosures: No relevant conflicts of interest to declare.

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Circulating cytokines and lymphocyte subsets in patients who have recovered from COVID-19

10.1101/2020.07.22.20160259 ◽

2020 ◽

Author(s):

Hasi Chaolu ◽

Xinri Zhang ◽

Xin Li ◽

Dongyan Li

Keyword(s):

T Cells ◽

B Cells ◽

Nk Cells ◽

Cd8 T Cells ◽

Cd4 T Cells ◽

Lymphocyte Subsets ◽

Healthy Controls ◽

Tnf Α ◽

Ifn Γ ◽

Circulating Cytokines

To investigate the immune status of people who previously had COVID-19 infections, we recruited patients 2 weeks post-recovery and analyzed circulating cytokines and lymphocyte subsets. We measured levels of total lymphocytes, CD4+ T cells, CD8+ T cells, CD19+ B cells, CD56+ NK cells, and the serum concentrations of interleukin (IL)-1, IL-4, IL-6, IL-8, IL-10, transforming growth factor beta (TGF-β), tumor necrosis factor alpha (TNF-α), and interferon gamma (IFN-γ) by flow cytometry. We found that in most post-recovery patients, levels of total lymphocytes (66.67%), CD3+ T cells (54.55%), CD4+ T cells (54.55%), CD8 + T cells (81.82%), CD19+ B cells (69.70%), and CD56+ NK cells(51.52%) remained lower than normal, whereas most patients showed normal levels of IL-2 (100%), IL-4 (80.88%), IL-6 (79.41%), IL-10 (98.53%), TNF-α (89.71%), IFN-γ (100%) and IL-17 (97.06%). Compared to healthy controls, 2-week post-recovery patients had significantly lower absolute numbers of total lymphocytes, CD3+ T cells, CD4+ T cells, CD8+ T cells, CD19+ B cells, and CD56+ NK cells, along with significantly higher levels of IL-2, IL-4, IL-6, IL-10, TNF-α, IFN-γ and IL-17. Among post-recovery patients, T cells, particularly CD4+ T cells, were positively correlated with CD19+ B cell counts. Additionally, CD8+ T cells positively correlated with CD4+ T cells and IL-2 levels, and IL-6 positively correlated with TNF-α and IFN-γ. These correlations were not observed in healthy controls. By ROC curve analysis, post-recovery decreases in lymphocyte subsets and increases in cytokines were identified as independent predictors of rehabilitation efficacy. These findings indicate that the immune system has gradually recovered following COVID-19 infection; however, the sustained hyper-inflammatory response for more than 14 days suggests a need to continue medical observation following discharge from the hospital. Longitudinal studies of a larger cohort of recovered patients are needed to fully understand the consequences of the infection.

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Flow Cytometric Detection of the Expression of CXCR4 on CD34+ Cells and the Distribution of Lymphocyte Subsets in Allogeneic Hematological Grafts.

Blood ◽

10.1182/blood.v106.11.5195.5195 ◽

2005 ◽

Vol 106 (11) ◽

pp. 5195-5195

Author(s):

Lulu Lu ◽

Yongping Song ◽

Baogen Ma ◽

Xiongpeng Zhu ◽

Xudong Wei ◽

...

Keyword(s):

Bone Marrow ◽

Flow Cytometry ◽

T Cells ◽

Cord Blood ◽

Peripheral Blood ◽

Lymphocyte Subsets ◽

Color Flow ◽

Hematopoietic Stem ◽

Cd34 Cells ◽

Mobilized Peripheral Blood

Abstract Background and objectives: Normal human bone marrow (BM), cord blood (CB) and mobilized peripheral blood (MPB) are the most commonly used sources for allogeneic hematopoietic stem cell transplantation (HSCT). The aim of this study was to detect the expression of CXCR4 on CD34+ cells and to assess the distribution of lymphocyte subsets in each type allograft. Methods: CD34+ cells were separated from BM (n=30), CB (n=30) and MPB (n=30) by the CD34 MultiSort Kit immunomagnetic bead system. The expression of CXCR4 on CD34+cells was assayed by double color flow cytometry. The lymphocyte subsets in each type of allograft were detected by three-color flow cytometry. The groups of monoclonal antibodies were used as the following: CXCR4-PE/CD34−Pecy5, CD8−FITC/CD4−R-PE/CD3−TC, CD45RA-FITC/CD45RO-PE/CD4−Pecy5, CD45RA-FITC/CD45RO-PE/CD8−Pecy5, and CD3−FITC/CD16+56-PE. Isotype-specific antibodies were used as controls. Results: The expression of CXCR4 of cord blood and mobilized peripheral blood CD34+ cells was lower than that of bone marrow cells (BM 40.21%±6.72%, CB 20.93%±3.96%, MPB 20.93%±3.96%, P <0.05). The difference between cord blood and mobilized peripheral blood was not significant (P>0.05). The CD3+CD8low and CD3+CD4−CD8low subsets were higher in BM than that of CB and MPB (BM 8.61%±1.40%, CB 3.31%±0.88%, MPB 5.11%±0.76%,P<0.01). The relative frequencies of the naïve CD45RA+ CD45RO− phenotype among CD4+ and CD8high T cells were highest in CB, and it was higher in MPB than in BM grafts (BM 28.09%±4.52%, 41.86 %±3.31%; CB83.83%±12.24%, 86.69%±6.12%; MPB 43.58%±4.54%, 57.64%±4.77%, P<0.01). Naïve T cells (CD45RA+ CD45RO−) were mobilized preferentially compared to memory T cells (CD45RA− CD45RO+)(P <0.01); The relative frequencies of NKT (CD3+CD16+56+) among lymphocytes were lower in CB than that in BM and MPB (CB 0.77±0.19, BM4.15±1.10, MPB 4.13±0.84, P<0.01). Conclusion: BM, CB and MPB allografts differ widely in cellular makeup of CD34+ cells and lymphocyte subsets, which are associated with the distinct characteristics after allogeneic HSCT from different allogeneic hematological sources.

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Immunomagnetic Depletion of CD25-Expressing T Cells from Donor Blood Removes a Mixed Population of Regulatory and Effector T Cells - Implications for Graft Engineering.

Blood ◽

10.1182/blood.v108.11.724.724 ◽

2006 ◽

Vol 108 (11) ◽

pp. 724-724

Author(s):

J. Joseph Melenhorst ◽

Jun Lu ◽

Edgardo Sosa ◽

Nancy F. Hensel ◽

A. John Barrett

Keyword(s):

Flow Cytometry ◽

T Cells ◽

T Cell ◽

Cd8 T Cells ◽

Cd4 T Cells ◽

T Cell Responses ◽

Substantial Proportion ◽

Absolute Increase ◽

Cell Responses ◽

Treg Population

Abstract CD4+CD25+FOXP3+ regulatory T cells (TR) control proliferative CD4 and CD8 T cell responses to self and foreign antigens such as cytomegalovirus (CMV) and tumor-specific antigens. Thus, depletion of CD25-expressing cells from a resting population of T cells prior to antigen stimulation could boost the generation of antigen-specific T cells for adoptive transfer to treat viral infection or tumors. We depleted peripheral blood mononuclear cells (PBMC) from nine CMV seropositive donors using Miltenyi CD25 microbeads (20 μl/107 cells). CD25-depleted or unmanipulated PBMC were stimulated with CMV pp65-expressing antigen presenting cells for 10–14 days with low dose IL-2, and intracellular interferon-gamma (IFNγ) production by flow cytometry was compared between CD25-depleted and -undepleted cultures. An absolute increase in antigen-specific CD4+ and CD8+ T cells was seen after CD25 depletion in 4/8 and 5/8 cultures respectively. However, in other cultures there was a decrease or no change in IFNγ+ CD4+ T cells in CD25-depleted cultures, suggesting that the pp65-specific precursor cells had also been removed. We then used 4 μl beads per 107 PBMC to selectively remove only the CD25bright (predominantly Treg) population in nine donors and confirmed by flow cytometry that only CD25bright cells had been removed from the starting population. However, real-time quantitative PCR (Q-PCR) showed that even though the CD25+ fraction was enriched in FOXP3-expressing cells, a substantial proportion of the CD25-depleted PBMC still expressed FOXP3. Flow cytometric analysis of FOXP3 expression by CD25+ and CD25-negative CD4+ T cells showed that a substantial proportion of CD25- cells expressed FOXP3, confirming that CD25 is not a suitable single marker for depletion of Tregs. Again no reproducible augmentation of antigen-specific T cell responses was observed: one and five donors showing an increase in CD4 and CD8+ antigen-specific T cells, respectively, while the remainder showed a decrease or no change in CD4+ and CD8+ IFNγ-producing cells. These results suggest that removal of CD25+ cells from PBMC using CD25 microbeads removes both Treg and pp65-specific effector CD4+ and CD8+ T cells. Further, since FOXP3 is induced in responder cells as confirmed by FOXP3 Q-PCR, depletion of Treg at the start of the cultures may only transiently alleviate the negative regulation of the antigen response. Thus, CD25 depletion using microbeads is not a reliable method to boost antigen specific T cell expansions because of the inadvertent removal of a portion of the memory response to the antigen. Since it recently has been demonstrated that Treg act as an IL-2 sink, the addition of this cytokine should functionally silence the Tregs while preserving the inflammatory response.

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The Number of CD4+ T-Lymphocytes in the Autograft Correlates with Outcome After Autologous Stem-Cell Transplantation in Relapsed Hodgkin Lymphoma and Diffuse Large B-Cell Lymphoma.

Blood ◽

10.1182/blood.v114.22.3422.3422 ◽

2009 ◽

Vol 114 (22) ◽

pp. 3422-3422

Author(s):

Rony Schaffel ◽

Maria L.S. Lima ◽

Adrienne B.M. Madureira ◽

Nelson Spector ◽

Helio S. Dutra

Keyword(s):

T Cells ◽

T Cell ◽

Cd8 T Cells ◽

Cd4 T Cells ◽

Univariate Analysis ◽

B Cell Lymphoma ◽

Median Number ◽

Facs Analysis ◽

Large B Cell Lymphoma ◽

Cd34 Cells

Abstract Abstract 3422 Poster Board III-310 Autologous stem-cell transplantation (ASCT) is the standard treatment for relapsed diffuse large B-cell lymphoma (DLBCL) and Hodgkin's lymphoma (HL). The absolute lymphocyte count (ALC) in the autograft has been shown to correlate with survival after ASCT for lymphomas, but which lymphocyte subset in the autograft is responsible for this effect remains unknown. The aim of the present study was to retrospectively evaluate the impact of the number of CD4+ and CD8+T-cells in the autograft on the outcomes of ASCT. Patients with a diagnosis of relapsed HL or DLBCL submitted to an ASCT between 1999 and 2006 were included. Patients were excluded if a sample of the autograft was unavailable. No patient had HIV infection. The mobilization scheme consisted of subcutaneous G-CSF in 70% of the patients. The remaining patients were given cyclophosphamide 1.5 g/m2 or 4g/m2 with G-CSF. The conditioning regimen was cyclophosphamide 6 g/m2, BCNU 300 mg/m2 and etoposide 1200 mg/m2 in all but two patients. Growth-factor support was started five days after the infusion. The ALC in the autograft was calculated as the lymphogate in the FACS analysis. T-cell count was calculated as the total number of CD3+ lymphocytes, and T-cell subsets were determined by the number of CD4+ or CD8+ cells in the autograft. The antibodies used in the FACS analysis were: anti- CD45-FITC (BD- PharMingen), anti- CD4-FITC/ CD8-PE/ CD3-PercP (BD- PharMingen) and anti- CD3-FITC (BD- PharMingen). Among the 48 patients (34 with HL and 14 with DLBCL) available for study, the median age was 34 years (12-65), 37 were males (73%), and advanced stage disease (Ann Arbor stage III or IV) was present in 38 patients (75%). The number of previous treatments ranged from one to four, and radiotherapy had been given to 51% of the patients. The median time from diagnosis to the ASCT was 1.8 years (0.4 to 15.3). The median numbers of infused cells were mononuclear cells 5.7×108/kg (1-15), CD34+cells 4.1×106/kg (1.7-19.6) and lymphocytes 261/mm3 (23-978). The median numbers of T-cell subpopulations were CD3+ 164/mm3 (7-706), CD4+ 68/mm3 (3-284), CD8+ 75/mm3 (3-401), CD4-CD8- 9/mm3 (0.3-154) and CD4+CD8+ 1.3/mm3 (0.01-15). Those values were used as cutoffs for the lymphocyte count comparisons. In univariate analysis, the mobilization scheme including chemotherapy was associated with a higher median number of collected CD34+ cells/Kg (8.0 vs 4.17, p= 0.003), with a lower median number of total lymphocytes (203 vs 372, p=0.003), CD3+ T-cells (144 vs 249, p=0.005), CD8+ T-cells (50 vs 114, p<0.001) and there was also a trend towards lower CD4+ T-cells (67 vs 102, p=0.09). There was no association between the CD4+ T-cell subgroups and the type of disease, time from diagnosis to transplant, number of days of apheresis, mobilization scheme, stage of disease, number of previous treatments, or CD34+ cell counts. The median follow-up of the living patients was 1.9 years from the ASCT. Survival curves could be determined for 46 patients: 27 were alive, and 19 patients had died at the time of this analysis. In the univariate analysis, the type of disease, ALC, CD3+, CD4+, CD8+ and CD4+CD8+ T-cells had a statistically significant association with the 2-year overall survival (OS). The best discriminator of survival was the number of CD4+ T-cells (95% vs 43%, p<0.001). Both CD4+ and CD4+CD8+ T-cells were also associated with better event-free survival (EFS) (55% vs 19%, p=0.001, and 53% vs 24%, p=0.003, respectively). Multivariate analyses of OS and EFS were performed, including the type of disease and the counts of CD4+ and CD4+CD8+ T-cells. Regarding OS, only CD4+ T-cells (HR 11.87, 95%CI 2.71-51.99, p=0.001) and disease type (HR 2.54, 95%CI 1.00-6.45, p=0.05) remained statistically significant. Regarding EFS, only CD4+ T-cells (HR 2.94, 95%CI 1.28-6.79, p=0.01) and CD4+CD8+ T-cells (HR 2.88, 95%CI 1.18-7.04, p=0.02) retained statistical significance. If the findings in this study are confirmed, efforts should be made to collect sufficient numbers of CD4+ cells in every patient. A carefully designed prospective study is needed to address this issue, and to better define the various lymphocyte subpopulations involved in this phenomenon. Disclosures No relevant conflicts of interest to declare.

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Resistance of Natural Killer and T Cells to Venetoclax Allows for Combination Treatment with Cancer Immunotherapy Agents

Blood ◽

10.1182/blood-2018-99-116405 ◽

2018 ◽

Vol 132 (Supplement 1) ◽

pp. 1118-1118 ◽

Cited By ~ 2

Author(s):

Elisabeth A Lasater ◽

An D Do ◽

Luciana Burton ◽

Yijin Li ◽

Erin Williams ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

B Cells ◽

Nk Cells ◽

Cd8 T Cells ◽

Cd4 T Cells ◽

Immune Cell ◽

Single Agent ◽

Employment Equity ◽

Equity Ownership

Abstract Introduction: Intrinsic apoptosis is regulated by the BCL-2 family of proteins, which consists of both anti-apoptotic (BCL-2, BCL-XL, MCL-1) and pro-apoptotic (BIM, BAX, BAK, BAD) proteins. Interaction between these proteins, as well as stringent regulation of their expression, mediates cell survival and can rapidly induce cell death. A shift in balance and overexpression of anti-apoptotic proteins is a hallmark of cancer. Venetoclax (ABT-199/GDC-0199) is a potent, selective small molecule BCL-2 inhibitor that has shown preclinical and clinical activity across hematologic malignancies and is approved for the treatment of chronic lymphocytic leukemia with 17p deletion as monotherapy and in combination with rituximab. Objective: To investigate the effects of BCL-2 inhibition by venetoclax on viability and function of immune-cell subsets to inform combinability with cancer immunotherapies, such as anti-PD-L1. Methods and Results: B cells, natural killer (NK) cells, CD4+ T cells, and CD8+ T cells in peripheral blood mononuclear cells (PBMCs) from healthy donors (n=3) were exposed to increasing concentrations of venetoclax that are clinically achievable in patients, and percentage of live cells was assessed by flow-cytometry using Near-IR cell staining. B cells were more sensitive to venetoclax (IC50 of ~1nM) than CD8+ T cells (IC50 ~100nM), NK cells (IC50 ~200nM), and CD4+ T cells (IC50 ~500nM) (Figure A). CD8+ T-cell subset analysis showed that unstimulated naive, but not memory cells, were sensitive to venetoclax treatment (IC50 ~30nM and 240nM, respectively). Resistance to venetoclax frequently involves compensation by other BCL-2 family proteins (BCL-XL and MCL-1). As assessed by western blot in PBMCs isolated from healthy donors (n=6), BCL-XL expression was higher in NK cells (~8-fold) and CD4+ and CD8+ T cells (~2.5-fold) than in B cells (1X). MCL-1 protein expression was higher only in CD4+ T cells (1.8-fold) relative to B cells. To evaluate the effect of venetoclax on T-cell function, CD8+ T cells were stimulated ex vivo with CD3/CD28 beads, and cytokine production and proliferation were assessed. Venetoclax treatment with 400nM drug had minimal impact on cytokine production, including interferon gamma (IFNg), tumor necrosis factor alpha (TNFa), and IL-2, in CD8+ effector, effector memory, central memory, and naïve subsets (Figure B). CD8+ T-cell proliferation was similarly resistant to venetoclax, as subsets demonstrated an IC50 >1000nM for venetoclax. Taken together, these data suggest that survival of resting NK and T cells in not impaired by venetoclax, possibly due to increased levels of BCL-XL and MCL-1, and that T-cell activation is largely independent of BCL-2 inhibition. To evaluate dual BCL-2 inhibition and PD-L1 blockade, the syngeneic A20 murine lymphoma model that is responsive to anti-PD-L1 treatment was used. Immune-competent mice bearing A20 subcutaneous tumors were treated with clinically relevant doses of venetoclax, murine specific anti-PD-L1, or both agents. Single-agent anti-PD-L1 therapy resulted in robust tumor regression, while single-agent venetoclax had no effect. The combination of venetoclax and anti-PD-L1 resulted in efficacy comparable with single-agent anti-PD-L1 (Figure C), suggesting that BCL-2 inhibition does not impact immune-cell responses to checkpoint inhibition in vivo. These data support that venetoclax does not antagonize immune-cell function and can be combined with immunotherapy targets. Conclusions: Our data demonstrate that significant venetoclax-induced cell death at clinically relevant drug concentrations is limited to the B-cell subset and that BCL-2 inhibition is not detrimental to survival or activation of NK- or T-cell subsets. Importantly, preclinical mouse models confirm the combinability of BCL-2 and PD-L1 inhibitors. These data support the combined use of venetoclax and cancer immunotherapy agents in the treatment of patients with hematologic and solid tumor malignancies. Figure Figure. Disclosures Lasater: Genentech Inc: Employment. Do:Genentech Inc: Employment. Burton:Genentech Inc: Employment. Li:Genentech Inc: Employment. Oeh:Genentech Inc: Employment. Molinero:Genentech Inc: Employment, Equity Ownership, Patents & Royalties: Genentech Inc. Penuel:Genentech Inc: Employment. Sampath:Genentech Inc: Employment. Dail:Genentech: Employment, Equity Ownership. Belvin:CytomX Therapeutics: Equity Ownership. Sumiyoshi:Genentech Inc: Employment, Equity Ownership. Punnoose:Roche: Equity Ownership; Genentech Inc: Employment. Venstrom:Genentech Inc: Employment. Raval:Genentech Inc: Consultancy, Employment, Equity Ownership.

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Circulating Cytokines and Lymphocyte Subsets in Patients Who Have Recovered from COVID-19

BioMed Research International ◽

10.1155/2020/7570981 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12

Author(s):

Hasichaolu ◽

Xinri Zhang ◽

Xin Li ◽

Dongyan Li

Keyword(s):

T Cells ◽

B Cells ◽

Nk Cells ◽

Cd8 T Cells ◽

Cd4 T Cells ◽

Lymphocyte Subsets ◽

Healthy Controls ◽

Cell Counts ◽

Tnf Α ◽

Ifn Γ

To investigate the immune status of people who previously had COVID-19 infections, we recruited two-week postrecovery patients and analyzed circulating cytokine and lymphocyte subsets. We measured levels of total lymphocytes, CD3+ T cells, CD4+ T cells, CD8+ T cells, CD19+ B cells, and CD56+ NK cells and the serum concentrations of interleukin- (IL-) 1, IL-4, IL-6, IL-8, IL-10, transforming growth factor beta (TGF-β), tumor necrosis factor alpha (TNF-α), and interferon gamma (IFN-γ) by flow cytometry. We found that in most postrecovery patients, levels of total lymphocytes (66.67%), CD3+ T cells (54.55%), CD4+ T cells (54.55%), CD8+ T cells (81.82%), CD19+ B cells (69.70%), and CD56+ NK cells (51.52%) remained lower than normal, whereas most patients showed normal levels of IL-2 (100%), IL-4 (80.88%), IL-6 (79.41%), IL-10 (98.53%), TNF-α (89.71%), IFN-γ (100%), and IL-17 (97.06%). Compared to healthy controls, two-week postrecovery patients had significantly lower absolute numbers of total lymphocytes, CD3+ T cells, CD4+ T cells, CD8+ T cells, CD19+ B cells, and CD56+ NK cells, along with significantly higher levels of IL-2, IL-4, IL-6, IL-10, TNF-α, IFN-γ, and IL-17. Among postrecovery patients, T cells, particularly CD4+ T cells, were positively correlated with CD19+ B cell counts. Additionally, CD8+ T cells were positively correlated with CD4+ T cells and IL-2 levels, and IL-6 positively correlated with TNF-α and IFN-γ. These correlations were not observed in healthy controls. By ROC curve analysis, postrecovery decreases in lymphocyte subsets and increases in cytokines were identified as independent predictors of rehabilitation efficacy. These findings indicate that the immune system gradually recovers following COVID-19 infection; however, the sustained hyperinflammatory response for more than 14 days suggests a need to continue medical observation following discharge from the hospital. Longitudinal studies of a larger cohort of recovered patients are needed to fully understand the consequences of the infection.

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2-BFI Attenuates Experimental Autoimmune Encephalomyelitis in Mice via Regulation of Lymphocytes Subsets

10.21203/rs.3.rs-72159/v1 ◽

2020 ◽

Author(s):

Xiaofeng Shang ◽

Tan Wang ◽

Nana Xi ◽

Huiqin Xu ◽

Rongyuan Zheng

Keyword(s):

Flow Cytometry ◽

T Cells ◽

B Cells ◽

Experimental Autoimmune Encephalomyelitis ◽

Cd4 T Cells ◽

Lymphocyte Subsets ◽

Inflammatory Cells ◽

Rt Pcr ◽

Autoimmune Encephalomyelitis ◽

Experimental Autoimmune

Abstract Background: Imidazoline compounds are well accepted to exhibit various pharmacological effects including antidepressant, anti-inflammatory, analgesic, anti-morphine tolerance and inhibit the activity of monoamine oxidase. 2-(-2-benzofuranyl)-2-imidazoline (2-BFI), a selective imidazoline 2 receptor (I2R) ligand, has been proven to exhibit therapeutic effects for various neuroimmunological diseases. However, the mechanism behind its neuroprotective properties remains elusive. Methods: In this study, we used 2-BFI for the treatment of mice with experimental autoimmune encephalomyelitis (EAE) induced by myelin oligodendrocyte glycoprotein (MOG33-55). The clinical signs of neurological deficits were evaluated daily. The demyelination and inflammatory infiltration in the CNS of mice with EAE were examined by Luxol Fast Blue (LFB) staining and hematoxylin-eosin (H&E) staining. Flow cytometry was utilized to examine the ratios of lymphocyte subsets in the periphery and CNS of mice with EAE. We also used Reverse Transcription–Polymerase Chain Reaction (RT-PCR) to observe the changes of expression of inflammatory cytokines by 2-BFI intervention. Results: We found that 2-BFI significantly reduced the incidence of EAE and attenuated the severity of neurological disability. Pathological staining showed that the infiltration of inflammatory cells and demyelination in the central nervous system (CNS) of the mice were markedly alleviated via 2-BFI intervention. To explore the mechanism of action of 2-BFI, we used flow cytometry to determine immunophenotypes in the spleen and CNS of the mice. We discovered that 2-BFI significantly decreased the ratio of CD28+ lymphocytes and B cells in the spleen of EAE mice. In the CNS, the expression of CD4+ T cells was downregulated by 2-BFI, while B cells and CD39+ lymphocytes were dramatically increased. RT-PCR also demonstrated that the level of IFN-γ mRNA secreted by CD4+T cells was lower than that in the CNS of EAE mice, while the levels of TGF- β and IL-10mRNA secreted by Treg and B cells were increased with 2-BFI intervention. Conclusion: 2-BFI could ameliorate EAE-induced neurobehavioral deficits and reduce the infiltration of inflammatory cells via regulating the activation and migration of lymphocyte subsets. This study provides a new explanation for the protective mechanism of 2-BFI in neuroimmune diseases.

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