Differential combination immunotherapy requirements for inflamed (warm) tumors versus T cell excluded (cool) tumors: engage, expand, enable, and evolve

BackgroundDifferent types of tumors have varying susceptibility to immunotherapy and hence require different treatment strategies; these cover a spectrum ranging from ‘hot’ tumors or those with high mutational burden and immune infiltrates that are more amenable to targeting to ‘cold’ tumors that are more difficult to treat due to the fewer targetable mutations and checkpoint markers. We hypothesized that an effective anti-tumor response requires multiple agents that would (1) engage the immune response and generate tumor-specific effector cells; (2) expand the number and breadth of the immune effector cells; (3) enable the anti-tumor activity of these immune cells in the tumor microenvironment; and (4) evolve the tumor response to widen immune effector repertoire.MethodsA hexatherapy combination was designed and administered to MC38-CEA (warm) and 4T1 (cool) murine tumor models. The hexatherapy regimen was composed of adenovirus-based vaccine and IL-15 (interleukin-15) superagonist (N-803) to engage the immune response; anti-OX40 and anti-4-1BB to expand effector cells; anti-PD-L1 (anti-programmed death-ligand 1) to enable anti-tumor activity; and docetaxel to promote antigen spread. Primary and metastatic tumor growth inhibition were measured. The generation of anti-tumor immune effector cells was analyzed using flow cytometry, ELISpot (enzyme-linked immunospot), and RNA analysis.ResultsThe MC38-CEA and 4T1 tumor models have differential sensitivities to the combination treatments. In the ‘warm’ MC38-CEA, combinations with two to five agents resulted in moderate therapeutic benefit while the hexatherapy regimen outperformed all these combinations. On the other hand, the hexatherapy regimen was required in order to decrease the primary and metastatic tumor burden in the ‘cool’ 4T1 model. In both models, the hexatherapy regimen promoted CD4+ and CD8+ T cell proliferation and activity. Furthermore, the hexatherapy regimen induced vaccine-specific T cells and stimulated antigen cascade. The hexatherapy regimen also limited the immunosuppressive T cell and myeloid derived suppressor cell populations, and also decreased the expression of exhaustion markers in T cells in the 4T1 model.ConclusionThe hexatherapy regimen is a strategic combination of immuno-oncology agents that can engage, expand, enable, and evolve the immune response and can provide therapeutic benefits in both MC38-CEA (warm) and 4T1 (cool) tumor models.

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Autologous Gamma-Delta T (GD-T) Cells in Acute Myeloid Leukemia (AML): Potential Immune Effector Cells for Minimal Disease?.

Blood ◽

10.1182/blood.v104.11.2538.2538 ◽

2004 ◽

Vol 104 (11) ◽

pp. 2538-2538

Author(s):

Joerg M. Aswald ◽

Xing-Hua Wang ◽

Sandra Aswald ◽

Loralyn A. Benoit ◽

Mark Minden ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Interferon Gamma ◽

Residual Disease ◽

Blast Cell ◽

Healthy Controls ◽

Immune Effector ◽

Effector Cells ◽

Immune Effector Cells

Abstract Prolonging event-free survival of AML with autologous activated immune cells is a promising concept. GD-T cells are a rare circulating lymphocyte population (1%) and a component of the innate immune system capable of exerting anti-neoplastic activity. Their role as potential anti-cancer immune effector cells deserves further exploration. It is noteworthy that GD-T cells are over-represented in reactive regions surrounding melanoma lesions. While patients with an accumulation of GD-T cells showed a survival benefit over those who did not, such increases were not present in patients with metastatic disease and high tumor cell burden (Bachelez, J. Invest. Dermatol.98:369,1992). Little is known about the role of GD-T cells as immuno-effectors, their absolute numbers in peripheral blood or the feasibility of purifying functional GD-T cells from patients with AML. We are interested in testing the clinical feasibility of using GD-T cells freshly purified from PB against minimal residual disease in AML. As a first step towards achieving this goal, we compared circulating GD-T cell levels sequentially in 33 AML patients with 20 healthy adult volunteers. We used ultra-low volume multi-color flow-cytometry and microbeads to measure absolute numbers of GD-T cells in PB. Functional studies were done by the chromium release assay and single-cell intra-cellular interferon-gamma detection. We observed that AML patients with a high leukemic blast cell burden (e.g. prior to chemotherapy) had marginally decreased GD-T cell levels compared with healthy controls: median 38/μl, Q1-Q3, 27–86/μl, versus median 83/μl, Q1-Q3, 45–122/μl, respectively, p= 0.051. We re-examined the AML patients at several time points after induction therapy and observed significantly increased numbers of GD-T cells in patients with lower but detectable residual disease (either molecular maker positive or borderline bone marrow blast infiltration by morphology) compared to patients with persistently high blast cell burden: median 105/μl, Q1-Q3, 105–133/μl versus median, 7/μl, Q1-Q3, 6–15/μl; p=0.008. Patients with residual disease also showed significantly higher numbers of absolute GD-T cells per microliter blood compared to those retested after they had achieved complete remission (CR); p=0.0025. In CR, GD-T cell counts remained lower than those of healthy individuals: median 33/μl, Q1-Q3, 22–35/μl versus median 83/μl, Q1-Q3, 45–122/μl; p=0.030. Interestingly, we found a sharp increase (on average, 4.9-fold higher than values obtained in CR) in GD-T levels at the time of very early morphologic (n=3) or molecular relapse (n=2). Hence, we were interested in studying the functional properties of the GD-T cells from AML patients. We were able to isolate functional GD-T cells from the PB of patients with AML in CR-1 in sufficient numbers and purity to assay for interferon-gamma and found that similar numbers of GD-T cells expressed the Th1 cytokine compared with healthy controls: 84% versus 93% of all GD-T cells, respectively. We also showed that GD-T cells were able to kill leukemic target cells (AML-OCI2) in vitro more efficiently than CD3+ T cells. Our data suggest that further studies to investigate the potential therapeutic role of autologous GD-T cells in patients with AML in CR are warranted.

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Latent Membrane Protein 1 Contributes to Deficient Cellular Immunity in NKTCL Patients

Blood ◽

10.1182/blood-2019-128622 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. 3969-3969

Author(s):

Xiaoyan Feng ◽

Yue Song ◽

Zhaoming Li ◽

Xudong Zhang ◽

Lugui Qiu ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Cellular Immunity ◽

Cd8 T Cells ◽

T Cell Exhaustion ◽

Immune Effector ◽

Effector Cells ◽

Cell Exhaustion ◽

Specific Ctls ◽

Immune Effector Cells

Introduction Extranodal NK/T cell lymphoma (NKTCL) is an aggressive malignance that is correlated closely with persistent Epstein-Barr virus (EBV) infection and belongs to a latency II EBV disease. Chronic persistent viral infection is known to result in T cell exhaustion, which will dramatically impede anti-tumor immunity. Delineating mechanisms of immunosuppression contributes to the development of novel immuno-therapeutically strategies. Herein, we described the immune status and possible role of latent membrane protein 1(LMP1) in NKTCL. Methods Peripheral blood mononuclear cells (PBMCs) from newly diagnosed NKTCL patients and age-matched healthy donors (HDs) were isolated and stained with surface marker or intracellular marker after permeabilization. The frequency of EBV-specific cytotoxic T cells (CTLs) was analyzed by staining with HLA-A2 tetramers assembled with synthetic peptides from LMP1. T cell proliferation was detected by dilution of stained CFSE, and apoptosis of T cells was performed via annexinV and 7-AAD dual-staining. Cytotoxicity assay of natural killer cells (NK) was measured by detecting apoptosis of CFSE-labeled K562 cells after co-culturing with PBMCs. All flow cytometry was performed by BD FACS CantoII, and analyzed with FlowJo software. Results PBMCs from 19 NKTCL patients and 18 HDs were analyzed, which showed that the patients had higher ratio of CD4+/CD8+ cells and lower frequency of CD3-CD56+NK cells, higher percentage of immunosuppressive CD4+CD25hiCD127low T regulatory cells (Tregs) and HLA-DR-CD11b+CD33+ myeloid derived suppressor cells (MDSCs). Notably, the ratio of CD8+/Tregs, a parameter representing immune effector cells status, was obviously decreased in NKTCL patients (Figure-a). Given the potential association of T cell exhaustion and NKTCL, we detected expression of T cell exhaustion markers on T cells from NKTCL patients, and found that both CD4+ and CD8+ T cells expressed much higher level of inhibitory molecules PD1, CTLA4, TIGIT and TIM3 in NKTCL patients than that of HDs (Figure-b). To further explore cellular immunity in NKTCL, T cells were divided into four subsets: CD45RA-CCR7+ central memory T cells (Tcm), CD45RA+CCR7+ terminally differentiated effector T cells (Temra), CD45RA+CCR7- naïve T cells (Tn), CD45RA-CCR7- effector memory T cells (Tem) (Figure-c). It showed that CD4+ T cells had lower Tcm, Temra and Tn but much higher proportion of Tem compared with HDs (Figure-d). Moreover, we found that expression of PD1 and CTLA4 were upregulated on all lymphocyte subsets in NKTCL patients than HDs (Figure-e). We collected additional 13 NKTCL patients and 10 HDs with positive HLA-A2 phenotype to measure percentages of EBV-specific CTLs, which showed that frequency of EBV-specific CTLs was remarkably decreased in NKTCL patients (Figure-f). In addition, EBV-specific CTLs from NKTCL patients were more likely to express higher levels of exhaustion markers but produced much less IFN-γ (Figure g-h). To explore the potent mechanism of immunosuppression in NKTCL, LMP1 attracted our attention, which had been proven capable of activating multiple signaling pathways to exert its oncogenesis function. To elucidate effect of LMP1 on immune cells, we constructed two LMP1-derived peptides and found that LMP1-derived peptides suppressed the proliferation of CD4+ and CD8+ T cells and inhibited IFN-γ production of CD8+ T cells and NK cells (Figure i-j). Meanwhile, LMP1 promoted apoptosis of both CD4+ and CD8+ T cells (Figure-k). Subsequently regulation of LMP1 on exhaustion markers of T cells were detected, which showed that PD1, CTLA4, TIGIT and TIM3 were significantly upregulated on both CD4+ and CD8+ T cells after treatment with LMP1 derived peptides (Figure-m). Furthermore, LMP1 impaired NK cytotoxicity ability, evidenced by decrease apoptosis of target cells (Figure-n). Besides its effect on immune effector cells, we also found that LMP1-expressing NKTCL cell lines obviously induced both Tregs and MDSCs after co-culture. Interestingly, the extent of induction by LMP1 of Tregs and MDSCs were in line with the expression level of LMP1 on NKTCL cells (Figure o-p). Conclusion Our study showed that LMP1 contributes to deficient cellular immunity in NKTCL patients, providing us with more insight into immunosuppressive in this entity of disease, which would lead to identification of novel treatment strategies. Figure Disclosures No relevant conflicts of interest to declare.

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Stem Cell Approach to Generate Chimeric Antigen Receptor Modified Immune Effector Cells to Treat Cancer

Blood ◽

10.1182/blood.v124.21.2437.2437 ◽

2014 ◽

Vol 124 (21) ◽

pp. 2437-2437 ◽

Cited By ~ 4

Author(s):

Alla Dolnikov ◽

Shen Sylvie ◽

Ning Xu ◽

Tracey O'Brien

Keyword(s):

Stem Cells ◽

T Cells ◽

Stem Cell ◽

T Cell ◽

B Cell ◽

Immune Effector ◽

Effector Cells ◽

Anti Tumour Activity ◽

Immune Effector Cells ◽

Tumour Activity

Abstract Allogeneic stem cell transplantation is a curative therapy for refractory, relapsed and high risk leukaemia and lymphoma. Despite improvements in leukaemia treatment the disease relapse occurs in 30-50% of patients and remains unacceptably high. There is thus a clear need for novel agents in the treatment of leukaemia relapse. Leukaemia specific T cells genetically modified with Chimeric Antigen Receptor (CAR) generated in the laboratory to target malignant cells is a novel approach with proven success in early phase human trials. Patient's own T cells can be genetically modified in the laboratory to target tumour associated antigens through the introduction of CAR. CAR-modified T cells are amplified ex vivo to numbers suitable for adoptive cell therapy and administered to the patient upon preconditioning. Unfortunately, CAR-modified mature T cells often rapidly differentiate into short-lived effector cells that exhibit limited anti-tumour activity in vivo. Here we propose to use CAR-modified haematopoietic stem cells (HSC) to generate CART- cells. We hypothesise that CAR-modified HSC will provide long-lasting supply of CAR-T cells mediating sustained anti-tumour activity. Umbilical cord blood-derived CD34+ cells enriched with HSC were genetically modified to express CAR targeting CD19 antigen(CAR19) widely expressed on B-cell malignancies. An optimised gamma-retroviral gene transfer method was used to transduce CD34+ stem cells with CAR19. CAR19-transduced stem cells generate CD33+ myeloid, CD56+ natural killer and CD34-CD7+ T cell precursors expressing CAR19 and undergo normal proliferation and differentiation in vitro in colony forming unit (CFU) assay. B cell development analysed in co-cultures with bone marrow stroma MS5 cells, however, was completely suppressed. CAR19-transduced CD34+ stem cells were transplanted to immunocompromised NOD-SCID IL2Rg-/- (NSG) mice to generate multilineage immune effector cells exhibited delayed early engraftment. It is relevant that CD19+ B cells regenerate first in this mouse model. Thus mice transplanted with CAR19-transduced stem cells exhibited severe CD19+ B cell depletion confirming the functionality of CAR19 expressed in human B cells. To promote T cell regeneration, CD34+ HSCs were co-cultured with Notch ligand DL4 for 1 week before infusion. CD3+T cells were detectable in the blood of mice infused with DL4-pre-cultured CD34+ HSCs as soon as 6 weeks post-transplant while control CD34+ stem cells that were not co-cultured without DL4 exhibited significantly delayed T cell regeneration. Importantly, reduced leukaemia burden was observed in mice reconstituted with CAR19-modified stem cells and infused with human CD19+ leukaemia NALM6 cells. These data proves the feasibility of the stem cell approach to generate potent immune effector cells capable of fighting cancer. Further analysis aimed to identify the role of different multilineage immune effector cells in mediating anti-tumour activity in stem cell reconstituted mice is currently being conducted. Disclosures No relevant conflicts of interest to declare.

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The intraductal injection of 5-fluorouracil for breast cancer: Preventive effect and immune response.

Journal of Clinical Oncology ◽

10.1200/jco.2012.30.15_suppl.e13559 ◽

2012 ◽

Vol 30 (15_suppl) ◽

pp. e13559-e13559

Author(s):

Tsuyoshi Mori ◽

Satoshi Wada ◽

Kelly Olino ◽

Barish H Edil ◽

Drew M. Pardoll ◽

...

Keyword(s):

Immune Response ◽

Mammary Gland ◽

T Cell ◽

Cancer Cells ◽

Tumor Incidence ◽

Fat Pad ◽

Regional Lymph Nodes ◽

Immune Effector ◽

Effector Cells ◽

Immune Effector Cells

e13559 Background: Chemotherapy has been shown to act as an immune response modifier. Many groups are using chemotherapy to induce immune responses such as by using low doses of cyclophosphamide. Building up on our previous work (Murata et al., 2006, Stearns et al., 2011), we demonstrate that intraductal (i.duc), but not the intravenous (IV) route of injection of chemotherapy to HER2/neu transgenic mouse mammary glands (MMG) alters the tumor environment to effectively induce immune effector cells. Methods: 1.Tumor-free survival: 5-fluorouracil (5FU) was administered intraductally to the MMGs on the left side of mice; the MMG on right side were untreated. 2. FACS analysis: 20w mice were administered 5FU 2 times in a 4 week interval i.duc only to the left side, IV, or no treatment (NT). At week 5, the mice were sacrificed and the regional lymph nodes (RLN) and spleen were removed. Lymphocytes from RLN and spleen were analyzed. 3. Tumor re-challenge: GT8 cancer cells were injected into the one side of 4th mammary gland fat pad of 12 week mice. The mice were then injected i.duc with 5-FU to all teats in the tumor implanted side, or IV or given NT. The surviving mice were re-challenged with GT8 cancer cells into the ipsilateral 3rd mammary gland fat pad, 4 weeks after the first inoculation. Results: 1. The tumor incidence in the 5FU treated side after 16 weeks was significantly lower (13% of 70 glands) compared to mice that received NT (34% of 150, p=0.001), and IV (28% of 70, p=0.03). The tumor incidence in the untreated side of 5FU-treated mice was also significantly lower (18% of 70) compared to the NT (p=0.01). 2. The number of CD8 T cell showed no change among the groups in the RLN but was significantly lower (p=0.01) in the spleen of the i.duc. The number of CD62LLOW+ T cell in treated side of RLN was significantly higher compared to the IV (p=0.02) and NT (p=0.02). The number of CD62LLOW+ was low in the spleen. 3. The survivors in the group previously treated with i.duc 5-FU were able to achieve a lasting rejection of the tumor re-challenge when compared to mice who previously received 5-FU IV. Conclusions: I.duc administration of 5FU into MMG effectively induced immune effector cells and prevented mammary tumor growth in HER2/neu transgenic mice.

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Next-generation cell therapies: the emerging role of CAR-NK cells

Hematology ◽

10.1182/hematology.2020002547 ◽

2020 ◽

Vol 2020 (1) ◽

pp. 570-578

Author(s):

Rafet Basar ◽

May Daher ◽

Katayoun Rezvani

Keyword(s):

T Cells ◽

Cell Therapy ◽

Natural Killer ◽

Γδ T Cells ◽

Antigen Receptors ◽

T Cell Therapy ◽

Cell Therapies ◽

Immune Effector ◽

Effector Cells ◽

Immune Effector Cells

Abstract T cells engineered with chimeric antigen receptors (CARs) have revolutionized the field of cell therapy and changed the paradigm of treatment for many patients with relapsed or refractory B-cell malignancies. Despite this progress, there are limitations to CAR-T cell therapy in both the autologous and allogeneic settings, including practical, logistical, and toxicity issues. Given these concerns, there is a rapidly growing interest in natural killer cells as alternative vehicles for CAR engineering, given their unique biological features and their established safety profile in the allogeneic setting. Other immune effector cells, such as invariant natural killer T cells, γδ T cells, and macrophages, are attracting interest as well and eventually may be added to the repertoire of engineered cell therapies against cancer. The pace of these developments will undoubtedly benefit from multiple innovative technologies, such as the CRISPR-Cas gene editing system, which offers great potential to enhance the natural ability of immune effector cells to eliminate refractory cancers.

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Soluble CD70: a novel immunotherapeutic agent for experimental glioblastoma

Journal of Neurosurgery ◽

10.3171/2009.11.jns09901 ◽

2010 ◽

Vol 113 (2) ◽

pp. 280-285 ◽

Cited By ~ 18

Author(s):

James Miller ◽

Guenter Eisele ◽

Ghazaleh Tabatabai ◽

Steffen Aulwurm ◽

Gabriele von Kürthy ◽

...

Keyword(s):

T Cells ◽

Immune Responses ◽

Malignant Gliomas ◽

Ectopic Expression ◽

Glioma Cells ◽

Interferon Γ ◽

Soluble Form ◽

Immune Effector ◽

Effector Cells ◽

Immune Effector Cells

Object Given the overall poor outcome with current treatment strategies in malignant gliomas, immunotherapy has been considered a promising experimental approach to glioblastoma for more than 2 decades. A cell surface molecule, CD70, may induce potent antitumor immune responses via activation of the costimulatory receptor CD27 expressed on immune effector cells. There is evidence that a soluble form of CD70 (sCD70) may exhibit biological activity, too. A soluble costimulatory ligand is attractive because it may facilitate immune activation and may achieve a superior tissue distribution. Methods To test the antiglioma effect of sCD70, the authors genetically modified SMA-560 mouse glioma cells to secrete the extracellular domain of CD70. They assessed the immunogenicity of the transfected cells in cocultures with immune effector cells by the determination of immune cell proliferation and the release of interferon-γ. Syngeneic VM/Dk mice were implanted orthotopically with control or sCD70-releasing glioma cells to determine a survival benefit mediated by sCD70. Depletion studies were performed to identify the cellular mediators of prolonged survival of sCD70-releasing glioma-bearing mice. Results The authors found that ectopic expression of sCD70 enhanced the proliferation and interferon-γ release of syngeneic splenocytes in vitro. More importantly, sCD70 prolonged the survival of syngeneic VM/Dk mice bearing intracranial SMA-560 gliomas. The survival rate at 60 days increased from 5 to 45%. Antibody-mediated depletion of CD8-positive T cells abrogates the survival advantage conferred by sCD70. Conclusions These data suggest that sCD70 is a potent stimulator of antiglioma immune responses that depend critically on CD8-positive T cells. Soluble CD70 could be a powerful adjuvant for future immunotherapy trials for glioblastoma.

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Antibody-based therapy of leukaemia

Expert Reviews in Molecular Medicine ◽

10.1017/s1462399409001215 ◽

2009 ◽

Vol 11 ◽

Cited By ~ 25

Author(s):

John C. Morris ◽

Thomas A. Waldmann

Keyword(s):

Monoclonal Antibodies ◽

T Cell ◽

B Cell ◽

Gemtuzumab Ozogamicin ◽

Cell Leukaemia ◽

Target Cells ◽

Immune Effector ◽

Effector Cells ◽

Prolymphocytic Leukaemia ◽

Immune Effector Cells

Over the past decade, monoclonal antibodies have dramatically impacted the treatment of haematological malignancies, as evidenced by the effect of rituximab on the response rate and survival of patients with follicular and diffuse large B cell non-Hodgkin's lymphoma. Currently, only two monoclonal antibodies – the anti-CD33 immunotoxin gemtuzumab ozogamicin and the CD52-directed antibody alemtuzumab – are approved for treatment of relapsed acute myeloid leukaemia in older patients and B cell chronic lymphocytic leukaemia, respectively. Although not approved for such treatment, alemtuzumab is also active against T cell prolymphocytic leukaemia, cutaneous T cell lymphoma and Sézary syndrome, and adult T cell leukaemia and lymphoma. In addition, rituximab has demonstrated activity against B cell chronic lymphocytic and hairy cell leukaemia. Monoclonal antibodies targeting CD4, CD19, CD20, CD22, CD23, CD25, CD45, CD66 and CD122 are now being studied in the clinic for the treatment of leukaemia. Here, we discuss how these new antibodies have been engineered to reduce immunogenicity and improve antibody targeting and binding. Improved interactions with Fc receptors on immune effector cells can enhance destruction of target cells through antibody-dependent cellular cytotoxicity and complement-mediated cell lysis. The antibodies can also be armed with cellular toxins or radionuclides to enhance the destruction of leukaemia cells.

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PD-L1 Checkpoint Blockade Augments Anti-Tumor Immune Response of GD2 or HER2-Bsab Ex Vivo Armed T-Cells (EVAT) Therapy in Osteosarcoma

Blood ◽

10.1182/blood-2019-131325 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. 1959-1959

Author(s):

Jeong A Park ◽

Hong fen Guo ◽

Hong Xu ◽

Nai-Kong V. Cheung

Keyword(s):

Immune Response ◽

T Cells ◽

T Cell ◽

Immune Checkpoint ◽

Bispecific Antibody ◽

Ex Vivo ◽

Activated T Cells ◽

The Impact ◽

Anti Tumor Activity

Background Ex Vivo Armed T-cells (EVAT) carrying zeptomoles (10-21M) of T-cell engaging GD2-bispecific antibody (GD2-EVAT) or HER2-bispecific antibodies (HER2-EVAT) have potent anti-tumor activity against GD2(+) and/or HER2(+) solid tumors. Strategies to further optimize this approach are highly relevant. PD-1 is a key immune checkpoint receptor expressed mainly by activated T-cells and mediates immune suppression by binding to its ligands PD-L1 or PD-L2. Upregulation of PD-L1 has been found in many cancers including osteosarcoma and associated with aggressive disease and poor outcome. While the use of immune checkpoint inhibitors (ICIs) seems logical, the ideal timing when combined with T-cell engaging bispecific antibody (T-BsAb) or EVAT has yet to be defined. Here, we described the effects of anti-PD-1 or anti-PD-L1 antibodies on GD2-EVAT or HER2-EVAT therapy and explored the impact of its timing in the treatment of osteosarcoma which is GD2(+), HER2(+) and PD-L1(+). Methods GD2-BsAb and HER-BsAb were built using the IgG(L)-scFv format (Can Immunol Res, 3:266, 2015, Oncoimmunology, PMID:28405494). T-cells from healthy volunteer donors were isolated, and cultured ex vivo in the presence of CD3/CD28 beads plus 30 IU/mL of interleukin 2 (IL-2). Between day 7 and day 14, activated T-cells (ATCs) were harvested and armed for 20 minutes at room temperature with GD2-BsAb or HER2-BsAb. In vivo anti-tumor activity against GD2(+), HER2(+), and PD-L1(+) osteosarcoma cell line xenografts was tested in BALB-Rag2-/-IL-2R-γc-KO mice. Anti-human PD-1 antibody (pembrolizumab, anti-PD-1) or anti-human PD-L1 antibody (atezolizumab, anti-PD-L1) were tested for synergy with GD2-EVAT or HER2-EVAT therapy. Results The PD-1 expression increased among T-cells that circulated in the blood, that infiltrated the spleen or the tumor after EVAT therapy. While anti-PD-L1 combination therapy with GD2-EVAT or HER2-EVAT improved anti-tumor response against osteosarcoma (P=0.0123 and P=0.0004), anti-PD-1 did not (all P>0.05). The addition of anti-PD-L1 significantly increased T-cell survival in blood and T-cell infiltration of tumor when compared to GD2-EVAT or HER2-EVAT alone (all P<0.0001). Treatment of GD2-EVAT or anti-PD-L1 plus GD2-EVAT downregulated GD2 expression on tumors, but anti-PD-1 plus GD2-EVAT did not. For the next step we tested the impact of different combination schedules of ICIs on GD2-EVAT therapy. Concurrent anti-PD-1 (6 doses along with GD2-EVAT therapy) interfered with GD2-EVAT, while sequential anti-PD-1 (6 doses after GD2-EVAT) did not make a significant effect (P>0.05). On the other hand, while the concurrent use of anti-PD-L1 did not show benefit on GD2-EVAT, sequentially administered anti-PD-L1 produced a significant improvement in tumor control when compared to anti-PD-L1 or GD2-EVAT alone (P=0.002 and P=0.018). When anti-PD-L1 treatment was extended (12 doses after GD2-EVAT), the anti-tumor effect was most pronounced compared to GD2-EVAT alone (P <0.0001), which translated into improved survival (P=0.0057). These in vivo anti-tumor responses were associated with increased CD8(+) tumor infiltrating lymphocytes (TILs) of tumor. Conclusion In the arming platform, large numbers of target-specific T-cells can be generated, and this EVAT therapy is a highly effective cellular treatment with high potency in preclinical models. In addition, the advantage of ex vivo cytokine release following T-cell arming and activation could reduce or avoid life threatening cytokine storm if such activation was to proceed in vivo. Adoptive T-cell therapy induced immune response upregulates the inhibitory immune checkpoint PD-1/PD-L1 pathway, and combination treatment with anti-PD-L1 antibody, especially when combined as sequential therapy and continuously treated, significantly improved anti-tumor effect of EVAT, partly through increase in CD8(+) TILs infiltration. Disclosures Xu: MSK: Other: co-inventors in patents on GD2 bispecific antibody and HER2 bispecific antibody. Cheung:Ymabs: Patents & Royalties, Research Funding.

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Immune Self-tuning in Renal Cell Carcinoma

European Oncology & Haematology ◽

10.17925/eoh.2010.06.1.70 ◽

2010 ◽

Vol 06 (01) ◽

pp. 70

Author(s):

Antonia Busse ◽

Ulrich Keilholz ◽

◽

Keyword(s):

Renal Cell Carcinoma ◽

Immune Response ◽

Cell Carcinoma ◽

Renal Cell ◽

Disease Stabilisation ◽

Tumour Regression ◽

Immune Effector ◽

Effector Cells ◽

Immune Effector Cells ◽

Inhibitory Molecules

Although renal cell carcinoma (RCC) is an immunogenic tumour, and although there is evidence that in a small proportion of cases antitumour immune responses may mediate tumour regression or at least disease stabilisation, patients with progressive disease have no effective antitumour immune response. Besides preventing recognition of the tumour by immune effector cells, RCC escapes the immune system by induction of tolerance through manipulating the function and proliferation of immune effector cells. This tuning of the immune response can occur by active suppression of immune effector cells through inhibitory molecules expressed on the tumour surface and through various tumour-secreted soluble factors, or it can be mediated indirectly by induction of immunosuppressive cells. This review provides an overview of the most common mechanisms that mediate immune tolerance in RCC and discusses the therapeutic perspectives of immunoregulatory strategies in the era of targeted therapies.

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Cellular side of acquired immunity (T cells)

10.1093/med/9780199642489.003.0049 ◽

2013 ◽

Cited By ~ 1

Author(s):

Assia Eljaafari ◽

Pierre Miossec

Keyword(s):

Immune Response ◽

T Cells ◽

Immune System ◽

Disease Process ◽

T Cell Response ◽

Th2 Cells ◽

Cell Mediated Immunity ◽

Immune Effector ◽

Effector Cells ◽

Th22 Cells

The adaptive T-cell response represents the most sophisticated component of the immune response. Foreign invaders are recognized first by cells of the innate immune system. This leads to a rapid and non-specific inflammatory response, followed by induction of the adaptive and specific immune response. Different adaptive responses can be promoted, depending on the predominant effector cells that are involved, which themselves depend on the microbial/antigen stimuli. As examples, Th1 cells contribute to cell-mediated immunity against intracellular pathogens, Th2 cells protect against parasites, and Th17 cells act against extracellular bacteria and fungi that are not cleared by Th1 and Th2 cells. Among the new subsets, Th22 cells protect against disruption of epithelial layers secondary to invading pathogens. Finally these effector subsets are regulated by regulatory T cells. These T helper subsets counteract each other to maintain the homeostasis of the immune system, but this balance can be easily disrupted, leading to chronic inflammation or autoimmune diseases. The challenge is to detect early changes in this balance, prior to its clinical expression. New molecular tools such as microarrays could be used to determine the predominant profile of the immune effector cells involved in a disease process. Such understanding should provide better therapeutic tools to counteract deregulated effector cells.

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