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 ◽  
...  

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.

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 1931-1931
Author(s):  
Patrice Chevallier ◽  
Nelly Robillard ◽  
Marina Illiaquer ◽  
Julie Esbelin ◽  
Mohamad Mohty ◽  
...  

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.


2018 ◽  
Vol 47 (6) ◽  
pp. 2407-2419 ◽  
Author(s):  
Hong-Min Wang ◽  
Xiao-Hong Zhang ◽  
Ming-Ming Feng ◽  
Yan-Jun Qiao ◽  
Li-Qun Ye ◽  
...  

Background/Aims: Interleukin (IL)-35 has immunosuppressive functions in autoimmune diseases, infectious diseases, and certain cancers. However, few studies have focused on its immunoregulatory activity in non-small cell lung cancer (NSCLC). Thus, we investigated the role of IL-35 in the pathogenesis of this disease. Methods: A total of 66 NSCLC patients and 21 healthy individuals were enrolled. IL-35 expression in peripheral blood and bronchoalveolar lavage fluid (BALF) was measured. The modulatory functions of IL-35 on purified CD4+ and CD8+ T cells from NSCLC patients were investigated in direct and indirect coculture systems with NSCLC cell lines. Results: IL-35 expression was significantly increased in BALF from the tumor site, but not in the peripheral blood of NSCLC patients. IL-35 did not affect the bioactivity including proliferation, cytokine production, cell cycle, and cellular invasion of NSCLC cells. It suppressed responses from type 1 T helper (Th1) and Th17 cells but elevated the regulatory T cell response in cultured CD4+ T cells from NSCLC patients, and reduced cytokine-mediated CD4+ T cells cytotoxicity to NSCLC cells. Moreover, IL-35 also inhibited cytotoxic gene expression in CD8+ T cells from NSCLC, reducing their cytolytic and noncytolytic functions. Conclusion: The results of this study suggest that IL-35 contributes to the dysfunction/exhaustion of T cells and limited antitumor immune responses in NSCLC.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2346-2346
Author(s):  
Mette Hoegh-Petersen ◽  
Minaa Amin ◽  
Yiping Liu ◽  
Alejandra Ugarte-Torres ◽  
Tyler S Williamson ◽  
...  

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.


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 ◽  
...  

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.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1219-1219
Author(s):  
Yoshitaka Zaimoku ◽  
Bhavisha A Patel ◽  
Sachiko Kajigaya ◽  
Xingmin Feng ◽  
Lemlem Alemu ◽  
...  

Background: Immune aplastic anemia (AA) is caused by cytotoxic T cells (CTLs) that destroy hematopoietic stem and progenitor cells. Regulatory T cells (Tregs) are reduced in AA and increase in response to immunosuppressive therapy (IST; Solomou E et al, Blood 2007). Recent studies suggested an immune regulatory role of regulatory B cells (Bregs). Human CD19+CD24hiCD38hi Bregs suppress Th1 response of CD4+ T cells as well as IFN-γ production by CD8+ CTLs (Mauri C, Menon M, J Clin Invest 2017). The quantity and/or function of Bregs are impaired in autoimmune diseases, malignancies, chronic graft-versus-host disease, and during rejection of transplanted organs. Methods: We investigated B cell phenotypes including CD24hiCD38hi Bregs in previously untreated severe AA (SAA) and very severe AA (VSAA) patients, and healthy individuals aged 18 years and older, and tested their correlation with severity and response to IST. Absolute numbers of lymphocyte subsets, including CD19+ B cells, CD8+ T cells, CD4+ T cells, and NK cell (TBNK), were quantified in fresh blood. Percentages of B cell subsets among total CD19+ B cells, including CD24hiCD38hi Bregs, CD24loCD38lo mature naïve B cells, CD24hiCD38lo memory B cells and CD24loCD38hi plasma cells/plasmablasts, were analyzed using cryopreserved peripheral blood mononuclear cells (PBMCs). Blood samples were obtained from patients close to time of diagnosis and before institution of definitive therapy. All patients were treated with horse anti-thymocyte globulin, cyclosporine, and eltrombopag between 2012 and 2018 at the Hematology Branch, NHLBI (clinicaltrials.gov NCT01623167). Results: TBNK analysis revealed no significant difference in total B cell counts in 104 AA patients compared to 40 healthy individuals (median, 137/μl [IQR, 73-212] vs 163/μl [106-242], P=.11); NK cells were significantly decreased in patients with AA, as previously reported (Gascon P et al, Blood 1986). Total B cell count did not correlate with severity of AA (P=.89) nor with overall response at six months (P=.93). CD8+ T cells and NK cells were lower in VSAA patients compared to SAA patients. None of the TBNK subsets was predictive of overall response in six months after IST. When we assessed the phenotype of B cells among 60 AA patients whose cryopreserved PBMCs were available, CD24hiCD38hi Bregs were markedly decreased as compared to 29 healthy individuals (0.31% [0.14-0.85%] vs 1.9% [1.3-3.6%], P=3×10-7; Figure, Table), while there was no significant difference in other B cell phenotypes. Among these 60 patients, the percentage of CD24hiCD38hi Bregs was especially decreased in VSAA patients compared to SAA (0.18% [0.11-0.34%] vs 0.50% [0.17-1.4%], P=.017). In contrast, CD24loCD38lo mature naïve B cells were higher in VSAA than in SAA (69% [58-86%] vs 60% [42-70%], P=.024). CD24hiCD38hi Breg frequency was positively associated with neutrophil and reticulocyte counts (correlation coefficients [r], 0.34 and 0.26, respectively), while the frequency of CD24loCD38lo mature naïve B cells was negatively correlated (r, -0.34 and -0.40). CD24loCD38lo mature naïve B cells before IST were significantly lower in 47 patients who achieved overall responses at six months compared to 13 non-responders (64% [42-71%), vs 73% [58-88%], P=.014), but CD24hiCD38hi Breg frequency was not correlated with IST responses. At six months after IST, CD24hiCD38hi Bregs in AA patients had recovered to levels present in healthy individuals (2.3% [0.98-4.8%]), in both 34 responders and five non-responders; non-responders showed non-significant increased CD24loCD38lo mature naïve B cells at six months (P=.068). Discussion: A deficit of circulating CD24hiCD38hi Bregs in immune AA with recovery after IST, as occurs with Tregs, suggests Bregs may contribute to the immune pathophysiology in AA. We unexpectedly observed a higher percentage of CD24loCD38lo mature naïve B cells to be associated with more severe disease and a lower probability of responses to IST. B cell phenotype analysis may be beneficial for monitoring of AA and predicting outcomes of therapy. Disclosures No relevant conflicts of interest to declare.


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

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.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 1087-1087
Author(s):  
Hidekazu Nishikii ◽  
Byung Su Kim ◽  
Antonio Pierini ◽  
Jeanette Baker ◽  
Dominik Schneidawind ◽  
...  

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.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1118-1118 ◽  
Author(s):  
Elisabeth A Lasater ◽  
An D Do ◽  
Luciana Burton ◽  
Yijin Li ◽  
Erin Williams ◽  
...  

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.


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

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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