Higher HHV-6 Reactivation After Cord Blood Allo-SCT Is Not Related to HHV-6 Cell Receptor CD46 Expression

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 1931-1931
Author(s):  
Patrice Chevallier ◽  
Nelly Robillard ◽  
Marina Illiaquer ◽  
Julie Esbelin ◽  
Mohamad Mohty ◽  
...  
Keyword(s):  
Stem Cells ◽  
T Cells ◽  
B Cells ◽  
Cord Blood ◽  
Nk Cells ◽  
B Lymphocytes ◽  
Cd8 T Cells ◽  
Peripheral Blood ◽  
Cd4 T Cells ◽  
Cell Receptor

Abstract Abstract 1931 Introduction: Cord Blood (CB) are increasingly used as an alternative stem cells source in adults for allogeneic Stem Cell Transplantation (allo-SCT). The risk of human herpes virus (HHV-6) reactivation is significantly higher after CB transplant vs unrelated peripheral blood stem cells (PBSC) allo-SCT (Chevallier et al, BMT 2010). Higher HHV-6 cell receptor CD46 expression on progenitor cells in CB may explain this difference (Thulke et al, Virol J 2006). Patients and Methods: We have prospectively compared the HHV-6 cell receptor CD46 expression on various cell subsets of three freshly harvested blood sources on one hand and of three graft sources on the other hand. 52 samples were used for the purpose of this study. They were issued from peripheral blood (PB, n=10), G-CSF mobilised PB (GCSF-PB, n=10), cord blood (CB, n=10), unmanipulated bone marrow (uBM, n=5), leukapheresis product (LP, n=10) and thawed CB graft (n=7). CD46 expression was assessed by FACS analysis using a FACS CANTO II (BD Biosciences, San Jose, CA, USA) on total lymphocytes, monocytes, NK cells, T and B cells subsets, plasmacytoid (pDCs) dendritic cells and stem cells. Results: As all cell subsets were found CD46 positive, CD46 mean fluorescence intensity (MFI) was then considered for comparison. When considering the three blood sources, CD46 MFI were found similar on T cells, CD4-/CD8+ and CD4-/CD8- T cells, NKT cells, Tregs, memory B lymphocytes, pDCs and CD34+ stem cells. CD46 MFI was significantly lower on CD4+/CD8- and CD4+/CD8+ T cells, transitional B cells, total and naïve B lymphocytes, and NK cells in CB while higher on monocytes. The highest CD46 MFI was observed on monocytes in CB and on CD4+/CD8+ T cells in GCSF-PB and PB. Also, highest CD46 MFI was detected on T cells compared to B lymphocytes and NK cells in all blood sources while CD46 MFI was higher on CD4+/CD8- T cells compared to CD8+/CD4- T cells. When considering the three graft sources, CD46 MFI was similar on CD4-/CD8- T cells and NKT cells. CD46 MFI was found significantly lower on all other sub-populations in thawed CB graft, except monocytes. The highest CD46 MFI was observed on monocytes in CB graft, on CD4+/CD8+ T cells in LP and on monocytes and on CD4+/CD8- T cells in uBM. Also, highest CD46 MFI was detected on T cells compared to B lymphocytes and NK cells in all graft sources while CD46 MFI was higher on CD4+/CD8- T cells compared to CD8+/CD4- T cells. Conclusion: This original study shows strong differences in term of quantitative CD46 expression between several blood and grafts samples. Our results suggest that other factors (such as another HHV-6 cell surface receptor) than the qualitative CD46 expression play a role in the higher HHV-6 reactivation observed after CB transplant in adults. Disclosures: No relevant conflicts of interest to declare.

Circulating immune markers predict the therapeutic effect in primary lung cancer.

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. e21203-e21203
Author(s):  
Liangliang Xu ◽  
Jitian Zhang ◽  
Li Yang ◽  
Guangqiang Shao ◽  
Taiyang Liuru ◽  
...  
Keyword(s):  
Lung Cancer ◽  
T Cells ◽  
B Cells ◽  
Nk Cells ◽  
Cd8 T Cells ◽  
Peripheral Blood ◽  
Cd4 T Cells ◽  
Blood Lymphocyte ◽  
Lymphocyte Subpopulations ◽  
Significant Difference

e21203 Background: Radiotherapy (RT), surgical resection (SR), and immunotherapy (IT) as main therapies in lung cancer have either suppressive or stimulatory effects on the immune system. It’s still unclear the mechanism involved in the systemic changes of immune cells in the blood. Peripheral blood lymphocyte subpopulations were useful markers for evaluating immune response in tumor patients. Hence, we aimed to systematically investigate the alteration of lymphocyte subpopulations during the local therapies to evaluate antitumor treatment effects. Methods: Blood samples were obtained EDTA coated tubes and then centrifuged gently for white blood cell separation. The white blood cells in 10% DMSO and 90% FBS were frozen slowly in -80°C refrigerator. The following fluorochrome-conjugated surface and nuclear antibodies were used in the lymphocyte subtyping: CD11b, CD45, CD19, CD3, CD56, CD4, CD8a, CD25,CD127 and FOXP3. The staining cells were detected in the BD FACS machine and data were analyzed by the paired T-test. The percentage of Lymphocytes, Myeloid cells, B cells, T cells, Treg, CD8+ T cells, CD4+ T cells, NK cells, and NKT were examined. Results: Between July 2019 and January 2020, a total of 176 patients eligible, including 135 RT patients and 29 SR patients,12 IT patients, with both blood collection with both Pre, During and End therapies. Before local therapies, the percentage of total T cells in the RT group was significantly higher than SR (RT v.s SR mean:64.1 v.s 55.3, P = 0.02) while CD8+ T cells (RT v.s SR mean:28.2 v.s 34.5, P = 0.04)and Tregs (RT v.s SR mean:0.0 v.s 0.1, P = 0.055) were lower. The baseline level of T cells and their subtypes showed a significant difference in these two group patients. After local therapies, myeloid cells, lymphocytes, CD4+ T cells, CD8+ T cells, NK cells were significant different. There is no significant difference due to the smaller number of IT patients. In the RT group, lymphocytes (Pre-RT v.s End-RT mean:75.2 v.s 54.3, P = 0.004) and B cells (Pre-RT v.s End-RT mean:12.6 v.s 8.0, P = 0.03) were significantly decreased while other subpopulations didn’t show any significant difference after RT. Interestingly, in the SR group, there was a significant increase in CD4+ T cells (mean:59.0 v.s 62.1, p = 0.02) a trend of reduction in CD8+ T cells (mean:34.5 v.s 32.0, p = 0.055) after SR. In addition, there was an increased trend of Tregs after IT. Conclusions: There are some different patterns of distribution in subtypes of leukocytes in operable and inoperable patients and between different therapies. All RT, SR and IT changed the distribution of peripheral blood lymphocyte subpopulations. Further validation study is warranted to validate our findings particularly in circulating lymphocytes and B cells as a marker to evaluate immune status after RT, CD4+ T cells and CD8+ T cells after SR, Tregs after IT, as well as their relationship with tumor microenvironment and implication for personalized care.

Activation of DR3 Signaling Expands Recipient Derived Regulatory T Cells and Enhances Donor Immune Reconstitution Derived from Allogeneic Hematopoietic Stem Cells

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 1087-1087
Author(s):  
Hidekazu Nishikii ◽  
Byung Su Kim ◽  
Antonio Pierini ◽  
Jeanette Baker ◽  
Dominik Schneidawind ◽  
...  
Keyword(s):  
Stem Cells ◽  
T Cells ◽  
B Cells ◽  
Regulatory T Cells ◽  
Cd8 T Cells ◽  
Peripheral Blood ◽  
Cd4 T Cells ◽  
Immune Reconstitution ◽  
Hematopoietic Stem ◽  
Hsc Transplantation

Abstract CD4+ Foxp3+ regulatory T cells (Treg) are a subpopulation of T cells which regulate the immune system, maintain the tolerance of self-antigens and enhance immune tolerance after transplantation. It was also reported that recipient derived Treg could provide immune privilege to allogeneic stem cells (HSC) after transplantation. However, the precise interaction with Treg and HSC has not been fully elucidated. In this study, we investigated the role of recipient derived Treg in the engraftment and immune reconstitution following transplantation of purified allogeneic HSC and the effectiveness of Treg expansion following activation of DR3 (Death receptor 3, also called as TNFRSF25) signaling in this model. 　We first tested the effect of Treg depletion using Foxp3-DTR mice in allogeneic HSC transplantation. In this system, FACS-sorted purified HSC (Lin-cKit+Sca1+ population) derived from WT-FVB mice (CD45.1+/H2kq+) were injected into lethally irradiated B6-Foxp3-DTR mice (CD45.2+/H2kb+) with or without pre-treatment of diphtheria toxin (DT). On day 0 and day 28 after transplantation decreased frequencies of Foxp3+ cells in residual recipient derived CD4+ T cells were observed in peripheral blood from the DT treated mice (P<0.001 on day 0, P<0.002 on day 28). Although total myeloid chimerism was comparable between control and DT-treated mice, the frequency of donor derived immune cells including CD4+ T cells (P<0.01 on day 56), CD8+ T cells (P<0.01 on day 56), and B220+ B cells (P<0.001 on day 56) was significantly decreased in DT-treated mice. These data suggested that recipient derived Treg play an important role in allogeneic immune reconstitution after transplantation. DR3 is a member of the TNF receptor superfamily and we previously reported the expansion of Treg by the activation of this signaling pathway (Kim et al, ASH abstract 2013). We next tested whether activation of DR3 signaling by its agonistic antibody would affect the donor immune reconstitution after allogeneic HSC transplantation. The frequencies of Foxp3+ cells in CD4+ T cells were significantly increased in thymus, spleen, peripheral blood, and bone marrow 4 days after antibody injection (P<0.01). Isolated Treg derived from antibody treated mice showed stronger suppressive function in the mixed lymphoid reaction compared with those from isotype antibody treated mice. The mice treated with antibody on day -4 were transplanted with purified allogeneic HSC on day 0. Antibody treated mice showed a higher frequency of donor derived CD4+ T cells (P<0.001 on day 28), CD8+ T cells (P<0.05 on day 28), and B220+ B cells (P<0.05 on day 28) in this allogeneic HSC transplantation model. In summary, our data suggest that recipient derived CD4+Foxp3+ Treg play an important role in donor immune reconstitution and the activation of DR3 signaling in recipient mice enhances donor immune reconstitution by expansion of recipient derived Treg. H.N and BS-K contributed equally to this work. Disclosures No relevant conflicts of interest to declare.

The Feature of Distribution and Clonality of TCR Vα and Vβ Repertoire in Cord Blood.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 5132-5132
Author(s):  
Shaohua Chen ◽  
Yangqiu Li ◽  
Lijian Yang ◽  
Dongzhi Cen ◽  
Si Chen ◽  
...  
Keyword(s):  
Stem Cells ◽  
T Cells ◽  
Cord Blood ◽  
Peripheral Blood ◽  
Healthy Adult ◽  
Cell Receptor ◽  
Hematopoietic Stem ◽  
Normal Peripheral Blood ◽  
Pcr Products ◽  
Adult Volunteers

Abstract Analysis of T cell receptor (TCR) Vα and Vβ repertoire is one of the sensitive methods to understand the distribution and clonality of T cells from different samples, which is used to identify clonal expansion T cells that response to tumor associated antigens. Cord blood has been used successfully as a source of hematopoietic stem cells for transplantation. Recently, stem cells transplantation was demonstrated more important as immunotherapy against malignance cells. And cord blood T cells are resourceful for production the specific CTL to use in leukemia immunotherapy. But the feature of distribution and clonality of TCR Vα and Vβ subfamily T cells in cord blood is not yet clearly defined. In the present study, the CDR3 of 29 TCR Vα and 24 Vβ subfamily genes were analyzed in T cells from 10 cases of cord blood, which obtained at delivery from full-term healthy pregnancies, using RT-PCR and genescan technique. Peripheral blood of nine cases healthy adult volunteers served as controls. The results showed that 15–19 of 29 Vα and 9–15 of Vβ subfamily T cells could be identified in the most cases, whereas only 2–4 of Vα subfamilies expressed was found in 3 cases. The most frequently expressed Vα subfamilies were Vα 3 and Vα 10 (100%), Vα 4, 5, 6, 8, 12, 15, 17 and Vα 21 (70%), Vα1, 13, 25, and Vα26 (60%), with a lower expression rate found in Vα16, 24 and Vα 28 (10%). Vα 9 and Vα 29 were not detected in both CB and healthy adults. In analysis of TCR Vβ repertoire, Vβ3, 5, 8 and Vβ9 genes could be identified in all samples, Vβ7 and Vβ13 could be found in 90% of samples, whereas Vβ4, 6, 11, 12, 18, 23 and Vβ24 were absent in all samples, which could be detected in normal peripheral blood samples. Genescan analysis showed that all PCR products of TCR Vα and Vβ subfamilies from cord blood displayed a Gaussian distribution of CDR3 lengths (multi-peaks), which are corresponding to polyclonal rearrangement pattern, except for tow cases, which displayed oligoclonal peak in Vα 24 or Vα28 respectively. In contrast, some Vα subfamily products from 8 of 9 cases of healthy adult volunteers contained at least an oligoclonal peak in different Vα subfamilies respectively, however, multi-peaks were found in all PCR products of TCR Vβ from normal peripheral blood. In conclusion, more than 20% of TCR Vα or Vβ subfamily T cells were absent in cord blood. The majority of TCR Vα and Vβ subfamily T cells in cord blood displayed polyclonality. Occasional oligoclonal peaks are identified in some cases.

Anti-GvHD Effect of Antithymocyte Globulin Is Mediated by Antibodies Binding to T Cells and Regulatory NK Cells, and Less So or Not at All by Antibodies Binding to Other Mononuclear Cell Subsets

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2346-2346
Author(s):  
Mette Hoegh-Petersen ◽  
Minaa Amin ◽  
Yiping Liu ◽  
Alejandra Ugarte-Torres ◽  
Tyler S Williamson ◽  
...  
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
B Cells ◽  
Nk Cells ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Antithymocyte Globulin ◽  
Chronic Gvhd ◽  
Wilcoxon Test ◽  
Effector Memory

Abstract Abstract 2346 Introduction: Polyclonal rabbit-anti-human T cell globulin may decrease the likelihood of graft-vs-host disease (GVHD) without increasing the likelihood of relapse. We have recently shown that high levels of antithymocyte globulin (ATG) capable of binding to total lymphocytes are associated with a low likelihood of acute GVHD grade 2–4 (aGVHD) as well as chronic GVHD needing systemic therapy (cGVHD) but not increased likelihood of relapse (Podgorny PJ et al, BBMT 16:915, 2010). ATG is polyclonal, composed of antibodies for antigens expressed on multiple cell subsets, including T cells, B cells, NK cells, monocytes and dendritic cells. These cell subsets may play a role in the pathogenesis of GVHD. The anti-GVHD effect of ATG may be mediated through killing/inhibition of one or several of these cell subsets (eg, T cells) or their subsets (eg, naïve T cells as based on mouse experiments naïve T cells are thought to play a major role in the pathogenesis of GVHD). To better understand the mechanism of action of ATG on GVHD, we set out to determine levels of which ATG fraction (capable of binding to which cell subset) are associated with subsequent development of GVHD. Patients and Methods: A total of 121 patients were studied, whose myeloablative conditioning included 4.5 mg/kg ATG (Thymoglobulin). Serum was collected on day 7. Using flow cytometry, levels of the following ATG fractions were determined: capable of binding to 1. naïve B cells, 2. memory B cells, 3. naïve CD4 T cells, 4. central memory (CM) CD4 T cells, 5. effector memory (EM) CD4 T cells, 6. naïve CD8 T cells, 7. CM CD8 T cells, 8. EM CD8 T cells not expressing CD45RA (EMRA-), 9. EM CD8 T cells expressing CD45RA (EMRA+), 10. cytolytic (CD16+CD56+) NK cells, 11. regulatory (CD16-CD56high) NK cells, 12. CD16+CD56− NK cells, 13. monocytes and 14. dendritic cells/dendritic cell precursors (DCs). For each ATG fraction, levels in patients with versus without aGVHD or cGVHD were compared using Mann-Whitney-Wilcoxon test. For each fraction for which the levels appeared to be significantly different (p<0.05), we determined whether patients with high fraction level had a significantly lower likelihood of aGVHD or cGVHD than patients with low fraction level (high/low cutoff level was determined from ROC curve, using the point with maximum sum of sensitivity and specificity). This was done using log-binomial regression models, ie, multivariate analysis adjusting for recipient age (continuous), stem cell source (marrow or cord blood versus blood stem cells), donor type (HLA-matched sibling versus other), donor/recipient sex (M/M versus other) and days of follow up (continuous). Results: In univariate analyses, patients developing aGVHD had significantly lower levels of the following ATG fractions: binding to naïve CD4 T cells, EM CD4 T cells, naïve CD8 T cells and regulatory NK cells. Patients developing cGVHD had significantly lower levels of the following ATG fractions: capable of binding to naïve CD4 T cells, CM CD4 T cells, EM CD4 T cells, naïve CD8 T cells and regulatory NK cells. Patients who did vs did not develop relapse had similar levels of all ATG fractions. In multivariate analyses, high levels of the following ATG fractions were significantly associated with a low likelihood of aGVHD: capable of binding to naïve CD4 T cells (relative risk=.33, p=.001), EM CD4 T cells (RR=.30, p<.001), naïve CD8 T cells (RR=.33, p=.002) and regulatory NK cells (RR=.36, p=.001). High levels of the following ATG fractions were significantly associated with a low likelihood of cGVHD: capable of binding to naïve CD4 T cells (RR=.59, p=.028), CM CD4 T cells (RR=.49, p=.009), EM CD4 T cells (RR=.51, p=.006), naïve CD8 T cells (RR=.46, p=.005) and regulatory NK cells (RR=.55, p=.036). Conclusion: For both aGVHD and cGVHD, the anti-GVHD effect with relapse-neutral effect of ATG appears to be mediated by antibodies to antigens expressed on naïve T cells (both CD4 and CD8), EM CD4 T cells and regulatory NK cells, and to a lesser degree or not at all by antibodies binding to antigens expressed on B cells, cytolytic NK cells, monocytes or DCs. This is the first step towards identifying the antibody(ies) within ATG important for the anti-GVHD effect without impacting relapse. If such antibody(ies) is (are) found in the future, it should be explored whether such antibody(ies) alone or ATG enriched for such antibody(ies) could further decrease GVHD without impacting relapse. Disclosures: No relevant conflicts of interest to declare.

Cytotoxic CD4+ T cells use granulysin to kill Cryptococcus neoformans, and activation of this pathway is defective in HIV patients

Blood ◽  
2006 ◽  
Vol 109 (5) ◽  
pp. 2049-2057 ◽  
Author(s):  
Chun Fu Zheng ◽  
Ling Ling Ma ◽  
Gareth J. Jones ◽  
M. John Gill ◽  
Alan M. Krensky ◽  
...  
Keyword(s):  
T Cells ◽  
Nk Cells ◽  
Cryptococcus Neoformans ◽  
Cd8 T Cells ◽  
Peripheral Blood ◽  
Cd4 T Cells ◽  
Peripheral Blood Lymphocytes ◽  
Effector Molecule ◽  
Microbicidal Activity ◽  
Anticryptococcal Activity

AbstractAn important mechanism of host defense to Cryptococcus neoformans involves the direct microbicidal activity of lymphocytes. The importance of CD4+ T cells is illustrated by the incidence of this infection in the acquired immunodeficiency syndrome (AIDS) patients; however, the relative activity of microbicidal CD4+ T cells compared with CD8+ T cells and natural killer (NK) cells has not been established. Further, although NK cells and CD8+ T cells use perforin or granulysin, respectively, to kill C neoformans, the effector molecule used by CD4+ T cells is not known. Experiments demonstrated that IL-2–activated peripheral blood lymphocytes from healthy adults acquire anticryptococcal activity, and surprisingly, that CD4+ T cells had the most profound effect on this activity. Using SrCl2induced degranulation and siRNA knockdown, granulysin was shown to be the effector molecule. Although activation by anti–CD3 + IL-2 resulted in the additional expression of perforin, this did not improve the anticryptococcal activity. Cryptococcal killing by CD4+ T cells was defective in human immunodeficiency virus (HIV)–infected patients due to dysregulated granulysin and perforin production in response to IL-2 or anti–CD3 + IL-2. In conclusion, CD4+ T cells are the major subset of cells responsible for killing C neoformans in peripheral blood. These cells use granulysin as the effector molecule, and priming is dysregulated in HIV-infected patients, which results in defective microbicidal activity.

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

2020 ◽  
Author(s):  
Hasi Chaolu ◽  
Xinri Zhang ◽  
Xin Li ◽  
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.

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

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1118-1118 ◽  
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.

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

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Hasichaolu ◽  
Xinri Zhang ◽  
Xin Li ◽  
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.

scholarly journals Decreased Levels of CD54 (ICAM-1)-Positive Lymphocytes in the Peripheral Blood in Untreated Patients with Active Juvenile Dermatomyositis

2000 ◽  
Vol 7 (4) ◽  
pp. 693-697 ◽  
Author(s):  
Maurice R. G. O'Gorman ◽  
Laura Bianchi ◽  
David Zaas ◽  
Virginia Corrochano ◽  
Lauren M. Pachman
Keyword(s):  
T Cells ◽  
B Cells ◽  
Nk Cells ◽  
B Lymphocytes ◽  
Peripheral Blood ◽  
Cell Activation ◽  
Juvenile Dermatomyositis ◽  
Healthy Children ◽  
B Cell Activation ◽  
Activation Markers

ABSTRACT Significant abnormalities are observed in the peripheral blood of juvenile dermatomyositis (JDM) patients with active disease. In this study, we confirm that there is a significant increase in the relative percentage of B lymphocytes in the peripheral blood of a group of untreated children with newly diagnosed active JDM compared to healthy children (P < 0.0001). In order to investigate if properties intrinsic to B cells contributed to their relative increase in JDM, the percentage of B cells expressing activation markers (CD23, CD25, CD54, and CD69) was measured and compared to pediatric controls. Compared to healthy children less than 10 years of age (not significantly different from the JDM group), the JDM patients had an increase in the proportion of lymphocytes expressing CD19 (B cells;P = 0.0017) and decreases in the percentage of lymphocytes that were CD3− CD16+ and/or CD56+ (NK cells; P = 0.01) and CD3+ CD8+ (T suppressor/cytotoxic cells;P = 0.02). There were no significant differences in any of the B-cell activation markers assessed. Of note, the percentage of CD54+ non-B lymphocytes (i.e., T cells and NK cells expressing CD54) was significantly lower in the JDM patients (25% ± 5%) than in the “age-related” healthy control group (43% ± 4%;P = 0.013). These results suggest the following for untreated children with active JDM: (i) the increase in the percentage of peripheral blood B cells is not due to intrinsic B-cell activation, and (ii) CD54/ICAM-1+ non-B cells, CD8+ T cells, and NK cells are being removed from circulation and may be participating in the pathophysiology of the disease.

Effects of Cord Blood Cell Subset Populations in the Development of the Dominant Cord Blood Unit in Non-Myeloablative Sequential Double Cord Blood Transplantation (DCBT).

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 3148-3148 ◽  
Author(s):  
David T. Ting ◽  
Karen Ballen ◽  
Thomas R. Spitzer ◽  
Richard L. Haspel ◽  
Michelle Dorn ◽  
...  
Keyword(s):  
T Cells ◽  
B Cells ◽  
Cord Blood ◽  
Nk Cells ◽  
Cd8 T Cells ◽  
Cord Blood Transplantation ◽  
Cell Populations ◽  
Blood Transplantation ◽  
Graft Outcome ◽  
The Difference

Abstract Umbilical cord blood has become an established alternative hematopoietic stem cell source for patients without suitable donors. However, single cord blood transplantation in adults has been associated with high mortality rates due to graft failure, delayed engraftment, and poor immune reconstitution. In order to improve engraftment, sequential cord blood transplantation has been employed. One consistent observation with this strategy has been the eventual dominance of one cord graft over the other. However, the factors that determine the fate of one cord over the other have not been well elucidated. Our previous work demonstrated that the dominant cord tends to have an initial higher CD34+ cell dose. This study attempted to identify other cell populations in the cord units that may determine which unit becomes the ultimate source of hematopoiesis. Forty patients with hematologic malignancies underwent non-myeloablative conditioning with fludarabine, melphalan, and ATG followed by two sequential cord blood infusions. All cord units were at least a 4/6 HLA match with the recipient and each other. GVHD prophylaxis consisted of cyclosporine & mycophenolate mofetil or FK-506 & rapamycin. Chimerism analysis of peripheral blood leukocytes was performed by PCR of short tandem repeat loci. Flow cytometry for T-cells (CD4 and CD8), B-cells (CD19), and NK cells (CD3−CD56+CD16− & CD3−CD56+CD16+) were done using standard immunofluorescence methods. A total of 10 patients were available for this analysis. The Wilcoxon signed rank test was used to evaluate the significance of the difference in cell populations between the transplanted cords on graft outcome. This analysis demonstrated that 80% (8 of 10) of the dominant cords had higher NK cells when compared to the rejected unit with average total NK cells of 4.15 x 106 vs 2.30 x 106 per kg of recipient, respectively. Total NK cells included both CD16− and CD16+ cells, but the difference was much higher for CD16+ NK cells, which represent a more mature NK phenotype. B-cells, CD4+ T-cells, and CD8+ T-cells were similar between the two cords. The mean total cell/kg of recipient for each subpopulation between cord units are summarized in Table 1. A trend towards a difference in NK cells (p=0.1) was observed; the small number of samples, however, limited the interpretation of the analysis. Future studies involving additional DCBT recipients are ongoing to better define the influence of NK cells as well as other cell populations including mesenchymal stem cells and T-reg cells on cord graft outcome. Mean Subpopulation Cell Count/kg of recipient between Cord Units Cord CD3+CD4+ T-Cells CD3+CD8+ T-Cells CD3−CD56+CD16− NK Cells CD3−CD56+CD16+ NK Cells Total NK Cells CD19− B-Cells Dominant Cells/kg 3.92E+06 (1.35–7.30E+06) 1.76E+06 (0.5–3.22E+06) 4.64E+05 (0.06–1.52E+06) 3.68E+06 (0.4–9.65E+06) 4.15E+06 (0.7–9.97E+06) 1.68E+06 (0.3–3.96E+06) Rejected Cells/kg 4.34E+06 (2.04–7.83E+06) 1.71E+06 (0.7–4.86E+06) 3.60E+05 (0.0–0.9E+06) 1.94E+06 (0.3–3.55E+06) 2.30E+06 (0.3–4.10E+06) 1.80E+06 (0.9–3.15E+06)

Sign in / Sign up

Export Citation Format

Share Document