Interrogating resistance mechanisms to PD-1 blockade therapy with CRISPR.

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. 3077-3077
Author(s):  
Davis Yuri Torrejon ◽  
Jesse Meir Zaretsky ◽  
Daniel Sanghoon Shin ◽  
Mykola Onyshchenko ◽  
Gabriel Abril-Rodriguez ◽  
...  

3077 Background: We tested the biological significance of the loss of function (LOF) mutations in JAK1 or JAK2 within the IFN-receptor-pathway and in beta-2-microglobulin (B2M), which had been found in patient biopsies with resistance to anti-PD-1 therapy. Methods: We used CRISPR/Cas9 genome editing to generate JAK1, JAK2 and B2M knockout (KO) sublines of HLA-A*02:01 MART-1 or NY-ESO-1 positive human melanoma cell lines, tested using in-vitro T cell co-culture systems and in a syngeneic mouse model (MC38) to analyze the in-vivo antitumor activity with anti-PD1 therapy. Results: The JAK2-KO cell line was insensitive to IFN-gamma induced signaling and growth arrest (p < 0.001 compared with IFN-alpha or beta), while the JAK1-KO cell line was insensitive to all three IFNs. Baseline MHC class I expression after JAK1-KO was unaffected (baseline-MFI 1230 JAK1-KO vs 1570 parental, p = 0.66), but the magnitude of change was lower upon IFN-gamma exposure compared to the parental (MFI change with IFN-gamma, 26% decrease for JAK1-KO vs 50% increase for parental). There was no difference in in-vitro cytotoxicity by NY-ESO-1-TCR transgenic T-cells against JAK1-KO-NY-ESO-1+ melanoma cells compared to the parental (78% vs 82% cytotoxicity at 10:1 E:T ratio, p NS). However, B2M-KO was resistant to killing by MART-1 specific T-cells (2% vs 96% cytotoxicity at 10:1 E:T ratio, p < 0.0001). On the other hand, in the MC38 model the significant antitumor activity of anti-PD-1 against the wild type cells was lost in both JAK2-KO and B2M-KO. The percentage of CD8+ T cells has a trend of increase with anti-PD1 compared to untreated in the MC38 wild type (p = 0.1 d12), and a trend of decrease in MC38 B2M-KO (p = 0.2 d12), but no change in JAK2-KO tumors (p = 0.7 d12). Conclusions: JAK1/2 LOF mutations result in insensitivity to IFN induced antitumor effects, but does not impair T cell recognition and cytotoxicity, while B2M LOF results in lack of antigen presentation to T cells and loss of antitumor activity. However both lead to in-vivo resistance to anti-PD-1 therapy, suggesting they do so by independent mechanisms.

Blood ◽  
2003 ◽  
Vol 102 (1) ◽  
pp. 200-206 ◽  
Author(s):  
Martin Wilhelm ◽  
Volker Kunzmann ◽  
Susanne Eckstein ◽  
Peter Reimer ◽  
Florian Weissinger ◽  
...  

Abstract There is increasing evidence that γδ T cells have potent innate antitumor activity. We described previously that synthetic aminobisphosphonates are potent γδ T cell stimulatory compounds that induce cytokine secretion (ie, interferon γ [IFN-γ]) and cell-mediated cytotoxicity against lymphoma and myeloma cell lines in vitro. To evaluate the antitumor activity of γδ T cells in vivo, we initiated a pilot study of low-dose interleukin 2 (IL-2) in combination with pamidronate in 19 patients with relapsed/refractory low-grade non-Hodgkin lymphoma (NHL) or multiple myeloma (MM). The objectives of this trial were to determine toxicity, the most effective dose for in vivo activation/proliferation of γδ T cells, and antilymphoma efficacy of the combination of pamidronate and IL-2. The first 10 patients (cohort A) who entered the study received 90 mg pamidronate intravenously on day 1 followed by increasing dose levels of continuous 24-hour intravenous (IV) infusions of IL-2 (0.25 to 3 × 106 IU/m2) from day 3 to day 8. Even at the highest IL-2 dose level in vivo, γδ T-cell activation/proliferation and response to treatment were disappointing with only 1 patient achieving stable disease. Therefore, the next 9 patients were selected by positive in vitro proliferation of γδ T cells in response to pamidronate/IL-2 and received a modified treatment schedule (6-hour bolus IV IL-2 infusions from day 1-6). In this patient group (cohort B), significant in vivo activation/proliferation of γδ T cells was observed in 5 patients (55%), and objective responses (PR) were achieved in 3 patients (33%). Only patients with significant in vivo proliferation of γδ T cells responded to treatment, indicating that γδ T cells might contribute to this antilymphoma effect. Overall, administration of pamidronate and low-dose IL-2 was well tolerated. In conclusion, this clinical trial demonstrates, for the first time, that γδ T-cell–mediated immunotherapy is feasible and can induce objective tumor responses. (Blood. 2003;102:200-206)


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 21-21
Author(s):  
Gisele Olinto Libanio Rodrigues ◽  
Julie Hixon ◽  
Hila Winer ◽  
Erica Matich ◽  
Caroline Andrews ◽  
...  

Mutations of the IL-7Rα chain occur in approximately 10% of pediatric T-cell acute lymphoblastic leukemia cases. While we have shown that mutant IL7Ra is sufficient to transform an immortalized thymocyte cell line, mutation of IL7Ra alone was insufficient to cause transformation of primary T cells, suggesting that additional genetic lesions may be present contributing to initiate leukemia. Studies addressing the combinations of mutant IL7Ra plus TLX3 overexpression indicates in vitro growth advantage, suggesting this gene as potential collaborative candidate. Furthermore, patients with mutated IL7R were more likely to have TLX3 or HOXA subgroup leukemia. We sought to determine whether combination of mutant hIL7Ra plus TLX3 overexpression is sufficient to generate T-cell leukemia in vivo. Double negative thymocytes were isolated from C57BL/6J mice and transduced with retroviral vectors containing mutant hIL7R plus hTLX3, or the genes alone. The combination mutant hIL7R wild type and hTLX3 was also tested. Transduced thymocytes were cultured on the OP9-DL4 bone marrow stromal cell line for 5-13 days and accessed for expression of transduced constructs and then injected into sublethally irradiated Rag-/- mice. Mice were euthanized at onset of clinical signs, and cells were immunophenotyped by flow cytometry. Thymocytes transduced with muthIL-7R-hTLX3 transformed to cytokine-independent growth and expanded over 30 days in the absence of all cytokines. Mice injected with muthIL7R-hTLX3 cells, but not the controls (wthIL7R-hTLX3or mutIL7R alone) developed leukemia approximately 3 weeks post injection, characterized by GFP expressing T-cells in blood, spleen, liver, lymph nodes and bone marrow. Furthermore, leukemic mice had increased white blood cell counts and presented with splenomegaly. Phenotypic analysis revealed a higher CD4-CD8- T cell population in the blood, bone marrow, liver and spleen compared in the mutant hIL7R + hTLX3 mice compared with mice injected with mutant IL7R alone indicating that the resulting leukemia from the combination mutant hIL7R plus hTLX3 shows early arrest in T-cell development. Taken together, these data show that oncogenic IL7R activation is sufficient for cooperation with hTLX3 in ex vivo thymocyte cell transformation, and that cells expressing the combination muthIL7R-hTLX3 is sufficient to trigger T-cell leukemia in vivo. Figure Disclosures No relevant conflicts of interest to declare.


2000 ◽  
Vol 74 (5) ◽  
pp. 2406-2413 ◽  
Author(s):  
Davorka Messmer ◽  
Ralf Ignatius ◽  
Christine Santisteban ◽  
Ralph M. Steinman ◽  
Melissa Pope

ABSTRACT Transmission of simian immunodeficiency virus SIVmac239Δnef (Δnef) to macaques results in attenuated replication of the virus in most animals and ultimately induces protection against challenge with some pathogenic, wild-type SIV strains. It has been difficult, however, to identify a culture system in which the replication of Δnef is severely reduced relative to that of the wild type. We have utilized a primary culture system consisting of blood-derived dendritic cells (DCs) and autologous T cells. When the DCs were fully differentiated or mature, the DC–CD4+ T-cell mixtures supported replication of both the parental SIV strain, 239 (the wild type), and its mutant withnef deleted (Δnef), irrespective of virus dose and the cell type introducing the virus to the coculture. In contrast, when immature DCs were exposed to Δnef and cocultured with T cells, virus replication was significantly lower than that of the wild type. Activation of the cultures with a superantigen allowed both Δnef and the wild type to replicate comparably in immature DC–T-cell cultures. Immature DCs, which, it has been hypothesized, capture and transmit SIV in vivo, are deficient in supporting replication of Δnef in vitro and may contribute to the reduced pathogenicity of Δnef in vivo.


Endocrinology ◽  
2010 ◽  
Vol 151 (1) ◽  
pp. 56-62 ◽  
Author(s):  
Arvind Batra ◽  
Besir Okur ◽  
Rainer Glauben ◽  
Ulrike Erben ◽  
Jakob Ihbe ◽  
...  

Abstract Besides being mandatory in the metabolic system, adipokines like leptin directly affect immunity. Leptin was found to be necessary in T helper 1 (Th1)-dependent inflammatory processes, whereas effects on Th2 cells are rarely understood. Here, we focused on leptin in T-helper cell polarization and in Th2-mediated intestinal inflammation in vivo. The induction of cytokine-producing Th1 or Th2 cells from naive CD4+ T cells under polarizing conditions in vitro was generally decreased in cells from leptin-deficient ob/ob mice compared with wild-type mice. To explore the in vivo relevance of leptin in Th2-mediated inflammation, the model of oxazolone-induced colitis was employed in wild-type, ob/ob, and leptin-reconstituted ob/ob mice. Ob/ob mice were protected, whereas wild-type and leptin-reconstituted ob/ob mice developed colitis. The disease severity went in parallel with local production of the Th2 cytokine IL-13. A possible explanation for the protection of ob/ob mice in Th1- as well as in Th2-dependent inflammation is provided by a decreased expression of the key transcription factors for Th1 and Th2 polarization, T-bet and GATA-3, in naive ob/ob T cells. In conclusion, these results support the regulatory function of the adipokine leptin within T-cell polarization and thus in the acquired immune system and support the concept that there is a close interaction with the endocrine system.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 3720-3720
Author(s):  
Yasuhiro Nagate ◽  
Sachiko Ezoe ◽  
Jiro Fujita ◽  
Takafumi Yokota ◽  
Michiko Ichii ◽  
...  

Abstract Background: Adult T-cell leukemia/lymphoma (ATLL) is a mature T-cell neoplasm, linked to the human T-cell lymphotropic virus, HTLV-1. Patients with ATLL are often at the risk of opportunistic infections. Some studies suggested that ATLL cells originate from HTLV-1-infected regulatory T cells (Tregs). It could be possible that this immunocompromised state is caused by the function of ATLL cells having similar phenotypes with Tregs. In this study, we examined the expression of immunosuppressive molecules associated with Tregs in ATLL cells, and analyzed their roles in the function of ATLL cells. Methods: The protocol of this study was approved by the Investigational Review Board of Osaka University Hospital. Peripheral blood mononuclear cells (PBMCs) were collected from 10 asymptomatic HTLV-1 carriers and 22 ATLL patients (1 with smoldering type, 5 with chronic type, 2 with lymphoma type, and 14 with acute type) after getting informed consent. PBMCs from 3 ATLL patients were separated into CD4+ CD7- CADM1+ATLL cells and adjacent CD4+CD7+ CADM1-normal T cells using Fluorescence-activated Cell Sorter (FACS), and cells in each fraction were subjected to total RNA sequencing experiments. Based on the results, we examined the expression patterns of CD39 and CD73 in HTLV-1 carriers or each type of ATLL patients, and also analyzed the immune functions of these molecules in ATLL tumor cells. Results: We compared whole transcriptome of ATLL cells and normal CD4+cells. Bioinformatic analyses showed that many genes associated with immunosuppressive functions were elevated or downregulated in ATLL cells. Among these genes we focused on CD39, CD73 and CD26, because they have recently been reported to be strongly associated with the functions of Tregs. CD39, expressed on normal Tregs, and extrinsic CD73 have immunosuppressive potential by catalyzing adenosine from extracellular ATP, and CD26 has opposite potential by resolving adenosine, which have a strong anti-inflammatory function and plays major role in Treg-mediated immunosuppression. We found that all of 4 ATLL cell lines (MJ, MT1, MT2, MT4) expressed CD39, but not CD73 just as human effector Tregs. Tumor cells from 12 acute ATLL patients (86%) and 2 chronic ATLL patients (40%) expressed CD39, but the expressions of CD73 were various. Also in asymptomatic carriers, we could detect CD39 and/or CD73 positive in CD7- CADM1+ abnormal fraction of CD4+cells. On the other hand, CD26, normally expressed on human CD4+Th cells other than effector Tregs, was negative in ATLL cell lines and primary ATLL cells except for cells in abnormal fraction of one asymptomatic carrier. CD39 negative cases in chronic/smoldering type tended to show slower disease progression after the blood collection. Next, the role of CD39 and/or CD73 in ATLL cells was assessed in vitro and in vivo. As expected, CD39+ ATLL cells converted significantly more extracellular ATP than CD39- ATLL cells, and mass spectrometry analysis of AMP/adenosine concentration identified the AMPase activity of CD73+ ATLL cells. Furthermore, we established CD39 knockout (KO) cells from ATL cell-line MJ using CRISPR/Cas9 system, and performed in vitro suppression assays for assessment of immunosuppressive function. Although wild type MJ suppressed the growth of normal CD4+ and CD8+ T cells, KO MJ did little. Next, we analyzed the role of CD39 in the progression of tumor cells in vivo. We transplanted mouse T-cell lymphoma cell-line EG7-OVA artificially expressing CD39 or mock into mice subcutaneously. The coinjection of immunoadjuvant poly(I:C) significantly suppressed the tumor growth of mock cells, but the tumor sizes of CD39 expressing cells were almost the same as those of mock cells without poly(I:C) injection (Figure). Conclusion: In this study, we reported that most of ATLL cells in acute type patients express CD39+ CD26- just as Tregs, and that CD39- KO of ATLL cell line cancelled its immunosuppressive effects, and forcibly expressed CD39 on tumor cells rejected the anti-tumor immunity in vivo. From these data, we clarified the pathological mechanism of immunosuppressive function in ATLL cells, and also showed that CD39 expression could be used as a prognostic clue and be a new therapeutic target of ATLL. Disclosures Ezoe: TAIHO Phamaceutical Co., Ltd.: Research Funding. Yokota:Celgene: Research Funding; Bristol-Myers Squibb: Research Funding; Pfizer Inc.: Research Funding; CHUGAI PHARMACEUTICAL CO., LTD.: Research Funding; MSD K.K.: Research Funding. Ichii:Novartis Pharma K.K.: Speakers Bureau; Kowa Pharmaceutical Co.,LTD.: Speakers Bureau; Celgene K.K.: Speakers Bureau. Shibayama:Novartis Pharma K.K.: Honoraria, Research Funding; Celgene K.K.: Honoraria, Research Funding; Takeda Pharmaceutical Co.,LTD.: Honoraria, Research Funding; Fujimoto Pharmaceutical: Honoraria, Research Funding; Jansen Pharmaceutical K.K: Honoraria; Ono Pharmaceutical Co.,LTD: Honoraria, Research Funding; Mundipharma K.K.: Honoraria, Research Funding; Bristol-Meyer Squibb K.K: Honoraria, Research Funding. Oritani:Novartis Pharma: Speakers Bureau. Kanakura:Alexion Pharmaceuticals, Inc.: Consultancy, Honoraria, Research Funding.


2021 ◽  
Author(s):  
Taylor L Hickman ◽  
Eugene Choi ◽  
Kathleen R Whiteman ◽  
Sujatha Muralidharan ◽  
Tapasya Pai ◽  
...  

Purpose: The solid tumor microenvironment (TME) drives T cell dysfunction and inhibits the effectiveness of immunotherapies such as chimeric antigen receptor-based T cell (CAR T) cells. Early data has shown that modulation of T cell metabolism can improve intratumoral T cell function in preclinical models. Experimental Design: We evaluated GPC3 expression in human normal and tumor tissue specimens. We developed and evaluated BOXR1030, a novel CAR T therapeutic co-expressing glypican-3 (GPC3)-targeted CAR and exogenous glutamic-oxaloacetic transaminase 2 (GOT2) in terms of CAR T cell function both in vitro and in vivo. Results: Expression of tumor antigen GPC3 was observed by immunohistochemical staining in tumor biopsies from hepatocellular carcinoma, liposarcoma, squamous lung cancer, and Merkel cell carcinoma patients. Compared to control GPC3 CAR alone, BOXR1030 (GPC3-targeted CAR T cell that co-expressed GOT2) demonstrated superior in vivo efficacy in aggressive solid tumor xenograft models, and showed favorable attributes in vitro including an enhanced cytokine production profile, a less-differentiated T cell phenotype with lower expression of stress and exhaustion markers, an enhanced metabolic profile and increased proliferation in TME-like conditions. Conclusions: Together, these results demonstrated that co-expression of GOT2 can substantially improve the overall antitumor activity of CAR T cells by inducing broad changes in cellular function and phenotype. These data show that BOXR1030 is an attractive approach to targeting select solid tumors. To this end, BOXR1030 will be explored in the clinic to assess safety, dose-finding, and preliminary efficacy (NCT05120271).


1998 ◽  
Vol 66 (10) ◽  
pp. 5020-5026 ◽  
Author(s):  
Junichi Yamaoka ◽  
Eijiro Nakamura ◽  
Yoshifumi Takeda ◽  
Sadao Imamura ◽  
Nagahiro Minato

ABSTRACT Streptococcal pyrogenic exotoxin C (SPEC), when injected intradermally, induces erythema in unsensitized rabbits. In the present study, we examined whether this erythema induction is due to the T-cell stimulatory activity of SPEC as a superantigen. Analysis by using single-residue mutant SPECs indicated that mutant SPECs Y15I, A16E, and Y17I, in which tyrosine 15, alanine 16, and tyrosine 17 were replaced with isoleucine, glutamic acid, and isoleucine, respectively, exhibited significantly reduced mitogenic activity for Vβ2+ human T cells in vitro, and Y15I showed as much as a 1,000-fold reduction. Y15I mutant SPEC, however, retained the ability to bind to major histocompatibility complex class II antigen and to form a homodimer, implying that residue 15 is critically important for the interaction of SPEC with T-cell antigen receptor β chains. When injected intradermally into normal rabbits, wild-type SPEC induced a characteristic erythema after 3 h in a dose-dependent fashion, which was associated with polymorphonuclear and mononuclear cell infiltration. This erythema formation was found to be severely suppressed by systemic pretreatment with cyclosporin A, suggesting the involvement of host T cells. Y15I mutant SPEC exhibited nearly 1,000-fold less erythema induction in vivo than wild-type SPEC. Altogether, the present results strongly suggest that erythema induction in rabbits by SPEC is attributable mostly to its T-cell stimulatory activity as a superantigen.


Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 456-456 ◽  
Author(s):  
Pavan Reddy ◽  
Yoshinobu Maeda ◽  
Raimon Duran-Struuck ◽  
Oleg Krijanovski ◽  
Charles Dinarello ◽  
...  

Abstract We and others have recently demonstrated that suberoylanilide hydroxamic acid (SAHA), a histone deacetylase (HDAC) inhibitor with anti-neoplastic properties, reduces experimental acute graft-versus-host disease (GVHD). We have now investigated the mechanisms of action of two HDAC inhibitors, SAHA and ITF 2357, on allogeneic immune responses. Bone marrow derived dendritic cells (DCs) were preincubated with the HDAC inhibitors at nanomolar concentrations for 16–18 hours and stimulated with lipopolysaccharide (LPS). Pretreatment of DCs caused a significant reduction in the secretion of TNF-α, IL-12p70 and IL-6 compared to the untreated controls (P< 0.005). Similar effects were seen using human peripheral blood mononuclear cell derived DCs. Pre-treatment of both murine and human DCs also significantly reduced their in vitro stimulation of allogeneic T cells as measured by proliferation and IFN-γ production (P<0.01). We determined the in vivo relevance of these observations utilizing a mouse model where the responses of allogeneic donor bm12 T cells depended on the function of injected host B6 DCs would stimulate. Recipient Class-II −/− B6 (H-2b) received 11 Gy on day -1 and were injected with 4–5 x 106 wild type B6 DCs treated with SAHA or with media on days -1 and 0 and then transplanted with 2 x 106 T cells and 5 x 106 TCDBM cells from either syngeneic B6 or allogeneic bm12 donors. SAHA treatment of DCs significantly reduced expansion of allogeneic donor CD4+ T cells on day +7 after BMT compared to controls (P<0.05). SAHA treatment induced a similarly significant reduction in the expansion of CD8+ cells in Class I disparate [bm1→β2M−/−] model. In vitro, SAHA treatment significantly suppressed the expression of CD40 and CD80 but did not alter MHC class II expression. Surprisingly, when mixed with normal DCs at 1:1 ratio, SAHA treated DCs dominantly suppressed allogeneic T cell responses. The regulation of T cell proliferation was not reversible by addition of IL-12, TNF-α, IL-18, anti-IL-10 or anti-TGFβ, either alone or in combination. Suppression of allogeneic responses was contact dependent in trans-well experiments. To address whether the regulation of SAHA treated DCs required contact with T cells, we devised a three cell experiment where SAHA treated DCs lacked the capacity to present antigens to T cells. DCs from B6 MHC Class II deficient (H-2b) were treated with SAHA and co-cultured with wild type B6 (H-2b) DCs along with purified allogeneic BALB/c (H-2d) CD4+ T cells in an MLR. Allogeneic CD4+ T cells proliferated well, demonstrating the regulation to be dependent on contact between SAHA treated DCs and T cells. To address the in vivo relevance of this suppression, we utilized a well characterized [BALB/c →B6] mouse model of acute GVHD. Recipient B6 animals received 11Gy on day -1 and were injected with of 5 million host type SAHA treated or control DCs on days −1, 0, and +2. Mice were transplanted on day 0 with 2 x 106 T cells and 5 x 106 BM from either syngeneic B6 or allogeneic BALB/c donors. Injection of SAHA treated DCs resulted in significantly better survival (60% vs. 10%, P < 0.01) and significantly reduced serum levels of TNF-α, donor T cell expansion and histopathology of GVHD on day +7 after BMT compared to the controls. We conclue that HDAC inhibitors are novel immunomodulators that regulate DC function and might represent a novel strategy to prevent GVHD.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1531-1531
Author(s):  
Paul Neeson ◽  
Amanda Shin ◽  
Tsin Tai ◽  
Karen Chen ◽  
Joanne Davis ◽  
...  

Abstract Adoptive transfer (AT) of autologous T cells genetically-redirected against tumor antigens has considerable potential as cancer immunotherapy [Kershaw, Nat Rev Immunol. 2005]. However, the in vivo persistence of AT T cells is critical for tumor control and requires the development (in vitro or in vivo) of a memory T cell subset. We investigated the generation of memory T cell subsets in a novel chimeric T cell receptor-expressing T cell product prior to, and after exposure to cognate antigen. Gene-modified T cells (LeY-T) express a chimeric receptor comprising a single chain variable fragment (scFv) specific for Lewis Y (LeY) antigen coupled to the intracellular signaling domains of CD3 zeta and CD28, capable of inducing T cell effector granule release and target killing [Westwood PNAS 2005]. To produce LeY-T cells, PBMC from healthy donors (n=20) or multiple myeloma patients (n=2) were cultured with anti-OKT3 (30ng/ml) and IL-2 (600IU/ml) for three days, followed by two rounds of transduction with retroviral supernatant. Subsequently, T cells were expanded in high dose IL-2 (600IU/ml) from day 5 onwards. T cells were harvested for this study on culture days 10–12, CD8+ and CD4+ T cells expressed the chimeric protein (50–60)%. LeY CD8+ T cell subsets were assessed as naïve (N), central memory (CM), effector memory (EM) or effector (E) based on three features:- phenotype (CD45RA, CCR7, CD28, CD27 and perforin); homeostatic cytokine (IL-15/IL-7) proliferation; response to Lewis antigen contact including cell proliferation and cytokine secretion. We repeatedly observed that CD8+ LeY-T cells analyzed directly from the initial expansion culture demonstrate an effector memory (EM) phenotype (CD45RA−/CCR7−/CD28+/perforinhi and variable CD27 expression) (Figure 1A). Furthermore in vitro expanded LeY CD8 T cells express IL- 15R beta (CD122) and the common gamma chain (CD132), they proliferate in response to IL-15 (86% cell division, division index 1.82), but less with IL-7 (30% cell division, division index 0.56). Baseline expanded CD8+ LeY-T cells respond to the presence of LeY antigen by proliferating and secreting IFN-gamma (4–8% of CD8 T cells) but not IL-2. Importantly, no IFN-gamma secretion was seen in control T cells transduced with empty vector (Figure 1B, OVCAR cells). Furthermore, no IFN-gamma was secreted by the control or the CD8+ LeY-T cells in response to the Lewis antigen negative cell line (Figure 1C, HCT116 cells). To explore the memory component further, we examined the functional status of the CD8+ LeY-T cells seven and 30 days following a 48-hour exposure to LeY antigen (OVCAR cells), and compared this to CD8+ LeY-T cell functional status at baseline. Thus, direct from transduction, expansion culture LeY CD8+ T cells were largely EM phenotype (95%) a small population of cells (1–5)% had a CM phenotype (CD45RA−/CCR7+/CD28+/perforinlo). In contrast, seven days after Lewis antigen contact the EM cells had decreased to (76–88)% and CM increased to (10–21)%; this distribution was retained up to day 30 post-antigen exposure. In addition, seven days after Lewis antigen exposure, CD8+ LeY-T cells retain the capacity to proliferate in response to Lewis antigen and to secrete IFN-gamma, at no stage do these cells secrete IL-2. In conclusion, the CD8+ LeY-T cells produced by in vitro transduction and expansion culture have an EM functional status direct from in vitro culture indicating that they are an appropriate starting population for in vivo adoptive transfer. After exposure to LeY expressed on tumor cell lines in vitro, CD8+ LeY T cells show further polarization to either EM or CM cells. These results suggest that the LeY-chimeric T cells have the potential to form long-term memory populations in vivo after adoptive transfer. Figure 1. LeY T cells have an effector memory phenotype and respond to Lewis antigen expressing cell lines by secreting IFN-gamma. Following the transduction culture, the CD8+ LeY-T cells (A) expressed high levels of perforin and an EM phenotype. In (B), LeY T or empty vector control T cells were co-cultured with tumour cells overnight and intracellular cytokine secretion assay performed. The LeY CD8+ T cells responded to Lewis antigen expressing OVCAR cells by secreting IFN-gamma, whereas no response was observed with the negative cell line HCT-116. Figure 1. LeY T cells have an effector memory phenotype and respond to Lewis antigen expressing cell lines by secreting IFN-gamma. Following the transduction culture, the CD8+ LeY-T cells (A) expressed high levels of perforin and an EM phenotype. In (B), LeY T or empty vector control T cells were co-cultured with tumour cells overnight and intracellular cytokine secretion assay performed. The LeY CD8+ T cells responded to Lewis antigen expressing OVCAR cells by secreting IFN-gamma, whereas no response was observed with the negative cell line HCT-116.


Blood ◽  
2012 ◽  
Vol 119 (3) ◽  
pp. 696-706 ◽  
Author(s):  
De-Gang Song ◽  
Qunrui Ye ◽  
Mathilde Poussin ◽  
Gretchen M. Harms ◽  
Mariangela Figini ◽  
...  

AbstractThe costimulatory effects of CD27 on T lymphocyte effector function and memory formation has been confined to evaluations in mouse models, in vitro human cell culture systems, and clinical observations. Here, we tested whether CD27 costimulation actively enhances human T-cell function, expansion, and survival in vitro and in vivo. Human T cells transduced to express an antigen-specific chimeric antigen receptor (CAR-T) containing an intracellular CD3 zeta (CD3ζ) chain signaling module with the CD27 costimulatory motif in tandem exerted increased antigen-stimulated effector functions in vitro, including cytokine secretion and cytotoxicity, compared with CAR-T with CD3ζ alone. After antigen stimulation in vitro, CD27-bearing CAR-T cells also proliferated, up-regulated Bcl-XL protein expression, resisted apoptosis, and underwent increased numerical expansion. The greatest impact of CD27 was noted in vivo, where transferred CAR-T cells with CD27 demonstrated heightened persistence after infusion, facilitating improved regression of human cancer in a xenogeneic allograft model. This tumor regression was similar to that achieved with CD28- or 4-1BB–costimulated CARs, and heightened persistence was similar to 4-1BB but greater than CD28. Thus, CD27 costimulation enhances expansion, effector function, and survival of human CAR-T cells in vitro and augments human T-cell persistence and antitumor activity in vivo.


Sign in / Sign up

Export Citation Format

Share Document