Cancer Immunotherapy: Cytotoxic Activity of γδ T-Cells Expanded Ex Vivo by the Third Generation Bisphosphonate Zoledronate.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 1347-1347
Author(s):  
Kiyoshi Sato ◽  
Shinya Kimura ◽  
Takeshi Yuasa ◽  
Hiromi Wada ◽  
Taira Maekawa
Keyword(s):  
T Cells ◽  
Antitumor Activity ◽  
Cytotoxic Activity ◽  
Ex Vivo ◽  
Γδ T Cells ◽  
Target Cells ◽  
Third Generation ◽  
Ras Proteins ◽  
Target Cancer

Abstract Bisphosphonates (BPs), widely used to treat bone diseases, have recently been attracted much interest for their antitumor activity and have been reported to exert direct antitumor effects on several cancer cell lines via the inactivation of Ras proteins. BPs inhibit farnesyl pyrophosphate (FPP) synthetase in the mevalonate pathway and deplete cellular pools of PPs such as farnesyl PP and geranylgeranyl PP which are indispensable for the activation of Ras proteins. In addition to their direct antitumor activity, BPs expand γδ T-cells which are potent effector cells and also induce the accumulation of isopentenyl PP as a tumor antigen in target cancer cells. The purpose of this study was to clarify the cytotoxic activity of γδ T-cells expanded ex vivo by the potent third generation BP zoledronate (ZOL). Peripheral blood mononuclear cells of five healthy donors were incubated with different concentrations of ZOL and interleukin-2. After 14 days incubation, 1 μM ZOL increased the absolute number of γδ T-cells 500–800 fold. Expanded γδ T-cells were of the Vγ9Vδ2 subset and cytokine levels of IL-2, -4, -5, -10, TNF-α and IFN-γ were not elevated at resting i.e. before contact to target cancer cells. In vitro cytotoxic activities of γδ T-cells against the luciferase-labeled small cell lung cancer (SCLC) cell line SBC-5 were examined by a newly developed cytotoxic assay using an in vivo imaging system (Xenogen, Alameda, CA) and video microscopy, Leica AS MDW (Leica Microsystems Inc., Bannockburn, IL). γδ T-cells killed SBC-5 cells pre-treated with 5 μM ZOL for 12 h after 1.5–3.0 h contact with the target cells whereas untreated SBC-5 were rarely killed. SBC-5 cells pretreated with 5 μM ZOL showed a marked increase in their sensitivity to lysis by γδ T-cells, percentages of specific lysis were 42% and 55% at effector/target (E/T) ratios of 5:1 and 10:1, respectively, while those of untreated SBC-5 cells were 8% and 13% at E/T ratios of 5:1 and 10:1, respectively. In vivo efficacy of γδ T-cells was investigated in mice xenografted subcutaneously with SBC-5 cells. Pretreatment with 80 μg/kg ZOL enhanced significantly antitumor activity of γδ T-cells also in vivo. These findings showed that ZOL stimulated the proliferation of γδ T-cells significantly and that the cytotoxic activity of γδ T-cells required pre-treatment of target cells with ZOL, indicating the potential use of autologous ex vivo expanded γδ T-cells for cancer immunotherapy.

scholarly journals Adoptively transferred ex vivo expanded γδ-T cells mediate in vivo antitumor activity in preclinical mouse models of breast cancer

2009 ◽  
Vol 122 (1) ◽  
pp. 135-144 ◽  
Author(s):  
Benjamin H. Beck ◽  
Hyung-Gyoon Kim ◽  
Hyunki Kim ◽  
Sharon Samuel ◽  
Zhiyong Liu ◽  
...  
Keyword(s):  
Breast Cancer ◽  
T Cells ◽  
Antitumor Activity ◽  
Mouse Models ◽  
Ex Vivo ◽  
Γδ T Cells ◽  
In Vivo Antitumor Activity

scholarly journals Effect of ex vivo-expanded γδ-T cells combined with galectin-1 antibody on the growth of human cervical cancer xenografts in SCID mice

2010 ◽  
Vol 33 (5) ◽  
pp. 280 ◽  
Author(s):  
Hua Li ◽  
Yubin Wang ◽  
FuXiang Zhou
Keyword(s):  
Cervical Cancer ◽  
T Cells ◽  
Antitumor Activity ◽  
Western Blot ◽  
Ex Vivo ◽  
Γδ T Cells ◽  
Antibody Treatment ◽  
Human Cervical Cancer

Objective: To investigate the antitumor activity of ex vivo-expanded γδ-T cells derived from tumor-infiltrating lymphocytes(γδTILs) from cervical cancer patients when combined with galectin-1 antibody and studied both in vitro and in vivo. Methods: The presence of γδTILs in cervical cancer specimens was detected by immunohistochemistry and γδTILs were expanded using the solid-phase antibody method. The expression of galectin-1 by the human cervical cancer cell line, SiHa, was measured by Western blot and ELISA. In vitro cytotoxic activities of expanded γδTILs, with or without galectin-1 inhibitor, were determined using the LDH-release test. In vivo antitumor activity of γδTILs, combined with galectin-1 antibody, was evaluated using the SCID mouse model. Results: γδTILs existed in the cervical cancer and the percentage of TCRγδ+ cells in γδTILs after ex vivo expansion was 91.2±1.2% detected by flow cytometry. SiHa cell expressed and secreted galectin-1 as measured by Western blot and ELISA. Expanded γδTILs from human cervical cancer demonstrated marked cytotoxicity to SiHa or Hela cells. In comparison with non-treated group, the cytotoxicity of γδ TILs towards SiHa or Hela cell was significantly increased when effector and target cells were incubated with either lactose or galectin-1 antibody at E/T ratio of 1:1 (p < 0.05). γδTILs, in combination with galectin-1 antibody treatment, significantly suppressed the growth of xenografts in SCID mice, in comparison with all other groups (p < 0.05). γδTILs alone also showed the ability to inhibit tumour growth in vivo, but were more efficient when combined with specific antibody (p < 0.05). Conclusion: Taken together, our results suggest that γδ-T cells, combined with galectin-1 antibody treatment, could be a more effective adoptive immunotherapy for patients with cervical cancer than traditional adoptive immunotherapy methods.

Cord blood comprises antigen-experienced T cells specific for maternal minor histocompatibility antigen HA-1

Blood ◽  
2005 ◽  
Vol 105 (4) ◽  
pp. 1823-1827 ◽  
Author(s):  
Bregje Mommaas ◽  
Janine A. Stegehuis-Kamp ◽  
Astrid G. van Halteren ◽  
Michel Kester ◽  
Jürgen Enczmann ◽  
...  
Keyword(s):  
T Cells ◽  
Cord Blood ◽  
Ex Vivo ◽  
Cytotoxic T Cells ◽  
Cord Blood Transplantation ◽  
Human Leukocyte ◽  
Leukemic Cells ◽  
Target Cells ◽  
Graft Versus Leukemia

AbstractUmbilical cord blood transplantation is applied as treatment for mainly pediatric patients with hematologic malignancies. The clinical results show a relatively low incidence of graft-versus-host disease and leukemia relapse. Since maternal cells traffic into the fetus during pregnancy, we questioned whether cord blood has the potential to generate cytotoxic T cells specific for the hematopoietic minor histocompatibility (H) antigen HA-1 that would support the graft-versus-leukemia effect. Here, we demonstrate the feasibility of ex vivo generation of minor H antigen HA-1-specific T cells from cord blood cells. Moreover, we observed pre-existing HA-1-specific T cells in cord blood samples. Both the circulating and the ex vivo-generated HA-1-specific T cells show specific and hematopoietic restricted lysis of human leukocyte antigen-A2pos/HA-1pos (HLA-A2pos/HA-1pos) target cells, including leukemic cells. The cord blood-derived HA-1-specific cytotoxic T cells are from child origin. Thus, the so-called naive cord blood can comprise cytotoxic T cells directed at the maternal minor H antigen HA-1. The apparent immunization status of cord blood may well contribute to the in vivo graft-versus-leukemia activity after transplantation. Moreover, since the fetus cannot be primed against Y chromosome-encoded minor H antigens, cord blood is an attractive stem cell source for male patients. (Blood. 2005;105:1823-1827)

γδ T cells for immune therapy of patients with lymphoid malignancies

Blood ◽  
2003 ◽  
Vol 102 (1) ◽  
pp. 200-206 ◽  
Author(s):  
Martin Wilhelm ◽  
Volker Kunzmann ◽  
Susanne Eckstein ◽  
Peter Reimer ◽  
Florian Weissinger ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Antitumor Activity ◽  
Low Dose ◽  
Γδ T Cells ◽  
Low Grade ◽  
Treatment Schedule ◽  
Γδ T Cell

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)

scholarly journals Vγ9Vδ2 T cells as a promising innovative tool for immunotherapy of hematologic malignancies

2011 ◽  
Vol 4 (4) ◽  
pp. 211
Author(s):  
Serena Meraviglia ◽  
Carmela La Mendola ◽  
Valentina Orlando ◽  
Francesco Scarpa ◽  
Giuseppe Cicero ◽  
...  
Keyword(s):  
T Cells ◽  
T Lymphocytes ◽  
Ex Vivo ◽  
Γδ T Cells ◽  
Hematologic Malignancies ◽  
Cytolytic Activity ◽  
Cell Therapies ◽  
Stressed Cells

The potent anti-tumor activities of γδ T cells, their ability to produce pro-inflammatory cytokines, and their strong cytolytic activity have prompted the development of protocols in which γδ agonists or ex vivo-expanded γδ cells are administered to tumor patients. γδ T cells can be selectively activated by either synthetic phosphoantigens or by drugs that enhance their accumulation into stressed cells as aminobisphosphonates, thus offering new avenues for the development of γδ T cell-based immunotherapies. The recent development of small drugs selectively activating Vγ9Vδ2 T lymphocytes, which upregulate the endogenous phosphoantigens, has enabled the investigators to design the experimental approaches of cancer immunotherapies; several ongoing phase I and II clinical trials are focused on the role of the direct bioactivity of drugs and of adoptive cell therapies involving phosphoantigen- or aminobisphosphonate-activated Vγ9Vδ2 T lymphocytes in humans. In this review, we focus on the recent advances in the activation/expansion of γδ T cells in vitro and in vivo that may represent a promising target for the design of novel and highly innovative immunotherapy in patients with hematologic malignancies.<br />

Anti-Tumor Cytotoxicity of Blood γδ T Cells Expanded from Leukemia Patients Against Autologous Leukemia Cells—Enhancement of the Anti-Tumor Cytotoxicity by Type I IFN.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 2385-2385
Author(s):  
Anri Saito ◽  
Miwako Narita ◽  
Norihiro Watanabe ◽  
Ayumi Yokoyama ◽  
Asuka Sekiguchi ◽  
...  
Keyword(s):  
T Cells ◽  
Cytotoxic Activity ◽  
Γδ T Cells ◽  
Leukemia Cells ◽  
Cellular Immunotherapy ◽  
Target Cells ◽  
Type I ◽  
Type I Ifn ◽  
Tnf Α ◽  
Tumor Cytotoxicity

Abstract In order to establish an efficient anti-tumor cellular immunotherapy using blood γδ T cells, we investigated the cytotoxic activity of γδ T cells expanded from patients with leukemia against autologous leukemia cells and explored the potent methods for enhancing the anti-tumor cytotoxic activity of γδ T cells. We clarified that γδ T cells generated from leukemia patients possess the cytotoxic activity against autologous leukemia cells. Besides, anti-tumor cytotoxic activity of expanded γδ T cells was enhanced by the short-term culture of γδ T cells with type I IFN (IFN-α and IFN-β). The sensitivity of target leukemia cells to γδ T cells was enhanced by the exposure of the target cells to bisphosphonate such as zoledronate, which is one of the antigens recognized by γδ T cells and elevates the content of potent antigen for γδ T cells, isoprenyl pyrophosphate (IPP), in tumor cells. Blood γδ T cells were expanded from anti-CD3 microbead-separated T cells or anti-γδ TCR microbead-separated γδ T cells in the patients with acute myelogenous leukemia by the culture with zoledronate and a low concentration of IL-2 for 1–2 weeks. For the activation of expanded γδ T cells, cultured γδ T cells were exposed with type I IFN for 1–3 days. The supernatant prepared from the culture of type I IFN-activated γδ T cells was assayed for cytokine (IFN-γ, TNF-α, IL-4, IL-5, IL-10) concentration by cytometric bead array. Anti-tumor cytotoxicity of γδ T cells was evaluated by 51Cr-release assay by using purified γδ T cells as effector cells and autologous leukemia cells as target cells. In most patients with acute leukemia, γδ T cells could be markedly expanded by the culture with zoledronate and IL-2 and almost all the expanded γδ T cells possessed Vδ2 TCR. Expanded and purified γδ T cells derived from the patients with leukemia were demonstrated to be cytotoxic against autologous leukemia cells. By the culture of expanded γδ T cells with type I IFN, the expression of the activation marker CD69 and the apoptosis molecule Trail was enhanced at the concentration dependent of type I IFN especially IFN-β. The expanded γδ T cells were shown to produce a remarkable amount of IFN-γ and a considerable amount of TNF-α and the cytokine production was increased by the addition of type I IFN. In addition, the cytotoxic activity of γδ T cells was enhanced by incubating target leukemia cells with zoledronate for 1–2 days. The present study demonstrated that γδ T cells expanded from patient’s blood are cytotoxic to patient’s leukemia cells. It is also demonstrated that there are two methods practically available for enhancing the cytotoxic activity of expanded γδ T cells against leukemia cells, one of which is activating γδ T cells by using type I IFN, and the other is elevating the sensitivity of target cells by using bisphosphonate. These findings implied the possibility that type I IFN-activated γδ T cells could be efficiently applied for cellular immunotherapy in the patients with hematological malignancies who is being administered with bisphosphonate. Moreover, in vivo administration of bisphosphpnate, a low dose of IL-2 and type I IFN could be effective for tumors as γδ T cell-based cellular immunotherapy.

In Vitro Expansion of Blood γδ T Cells in Patients with Myeloma/Lymphoma and Anti-Tumor Cytotoxicity of the Expanded γδ T Cells.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 3895-3895
Author(s):  
Anri Saito ◽  
Miwako Narita ◽  
Norihiro Watanabe ◽  
Nozomi Tochiki ◽  
Yumi Hiroi ◽  
...  
Keyword(s):  
T Cells ◽  
Cytotoxic Activity ◽  
Tumor Cells ◽  
Γδ T Cells ◽  
Cellular Immunotherapy ◽  
Target Cells ◽  
Type I ◽  
Type I Ifn ◽  
Lymphoma Cells

Abstract In order to establish an efficient anti-tumor cellular immunotherapy using blood In order to establish an efficient anti-tumor cellular immunotherapy using blood γδ T cells, we investigated the in vitro expansion of γδ T cells in the patients with myeloma and lymphoma by the culture of PB-MNC with bisphosphonate and a low dose of IL-2 and we demonstrated the cytotoxic activity of the expanded γδ T cells against myeloma/lymphoma cells. Simultaneously we explored the potent methods for enhancing the anti-tumor cytotoxic activity of γδ T cells by both directions of activating the expanded γδ T cells and making target tumor cells sensitive to γδ T cells. For the activation of γδ T cells, expanded γδ T cells were exposed with type I IFN, monocyte-derived dendritic cells (mo-DC), or plasmacytoid dendritic cell like cell line PMDC05 (leukemia cell line established from CD4+ CD56+ acute leukemia in our laboratory) for 2 days. For the enhancement of sensitivity of target tumor cell to γδ T cells, we aimed to increase the content of IPP (the potent pyrophosphate antigen for γδ T cells) in tumor cells by decreasing the metabolic downstream of IPP. For decreasing the downstream of IPP, we tried to suppress FPP synthetase, which is involved in downstream metabolism of IPP, by using nitrogen-containing bisphosphonate. In addition, the expression of stress-induced molecules such as MICA/B on target tumor cells was evaluated in association with the level of cytotoxicity of γδ T cells against the tumor cells. Compared with normal control, the patients with myeloma (n=8) demonstrated decreased percentage and counts of PB γδ T cells. Patients with lymphoma (n=7) showed a wide range of values in PB γδ T cells, covering a normal range. Amplification rate of PB γδ T cells by culture with zoledronate and IL-2 varied markedly from patient to patient up to 120 times in myeloma and 90 times in lymphoma. Expanded γδ T cells generated in patients with myeloma/lymphoma were demonstrated to possess the cytotoxic activity against myeloma/lymphoma cells by 51Cr-release assay and CFSE-labeled target cell. The cytotoxic activity of expanded γδ T cells was enhanced by the exposure of γδ T cells with type I IFN (IFN-α and IFN-β). The activation of γδ T cells, which was evaluated by the elevation of CD69 expression, was observed by the exposure of γδ T cells with type I IFN, mo-DC, or PMDC05 for 2 days. The sensitivity of target myeloma/lymphoma cells to γδ T cells was enhanced by the exposure of the target cells to bisphosphonate such as zoledronate. The expression level of MICA/B on target tumor cells was demonstrated to be associated with the potency of cytotoxicity of γδ T cells against the tumor cells. The present study demonstrated that γδ T cells expanded from myeloma/lymphoma patient’s blood are cytotoxic to myeloma/lymphoma cells. There are two methods practically available for enhancing the cytotoxic activity of expanded γδ T cells against myeloma/lymphoma cells, one of which is activating γδ T cells and the other is elevating the sensitivity of target cells by using bisphosphonate.

Robust Induction Of Th1-Like γδ T Cells With Anti-Myeloma Activity By Lenalidomide In Combination With HMB-PP As Well As Zoledronic Acid

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 129-129
Author(s):  
Takeshi Harada ◽  
Qu Cui ◽  
Shingen Nakamura ◽  
Hirokazu Miki ◽  
Asuka Oda ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
Zoledronic Acid ◽  
Cytotoxic Activity ◽  
Immune Cells ◽  
Mononuclear Cells ◽  
Conflicts Of Interest ◽  
Ex Vivo ◽  
Γδ T Cells ◽  
Bone Marrow Microenvironment

Abstract Multiple myeloma (MM) still remains incurable even with the implementation of novel therapeutic modalities, leading to the idea to develop various forms of immunotherapies. In this regard, γδ T cells bearing Vγ9Vδ2 TCR expanded from peripheral blood mononuclear cells (PBMCs) have attracted attention as potent effectors available in a novel immunotherapy against MM. Human Vγ9Vδ2 γδ T cells can be expanded ex vivo by aminobisphosphonates in combination with IL-2, and effectively target and impair MM cells. However, MM cells appear to protect themselves from external insults by immune cells in a unique bone marrow microenvironment created by the accumulation of mesenchymal stem cells/bone marrow stromal cells (BMSCs) with defective osteoblastic differentiation and acid-producing osteoclasts. To improve the therapeutic efficacy of γδ T cells, therefore, we need to develop a maneuver to effectively enhance the expansion and activity of γδ T cells while disrupting the MM cell-bone marrow interaction. Lenalidomide (Len), a novel immunomodulatory anti-MM agent, shows pivotal anti-MM activity by targeting immune cells as well as the interaction of MM cells and their surrounding cells in the bone marrow. The present study was undertaken to explore the efficacy of Len in combination with zoledronic acid (Zol) or a precursor of isopentenyl pyrophosphate (IPP) (E)-4 hydroxy-3-methyl-but-2-enyl pyrophosphate (HMB-PP), a microbial antigen for Vγ9Vδ2 TCR, on the induction and expansion of Th1-like γδ T cells with enhanced cytotoxic activity against MM cells in the skewed bone marrow microenvironment in MM. When combined with Zol (1μM), clinically relevant doses of Len (around 1 μM) substantially expanded γδ T cells from PBMCs to the levels similar to IL-2 (100 U/ml). Len was able to expand γδ T cells more robustly in combination with HMB-PP (1 μM) than Zol from PBMCs from the majority of normal donors. However, Len alone did not show any significant effects on γδ T cell expansion and activation, suggesting a costimulatory role of Len on Zol or HMB-PP-primed γδ T cells. The surface expression of LFA-1, and the cytotoxicity-associated molecules NKG2D, DNAX accessory molecule-1 (DNAM-1; CD226) and TRAIL were up-regulated in the expanded γδ T cells. Although functional diversity has been demonstrated in γδ T cells expanded by various stimuli, Len in combination with either Zol or HMB-PP enhanced intracellular IFN-γ along with the surface NKG2D but not Foxp3 in γδ T cells at higher levels than IL-2, suggesting robust induction of Th1-like γδ T cells by Len. Importantly, γδ T cells expanded with the combinatory treatments with Len and Zol or HMB-PP exerted potent cytotoxic activity against MM cells but not normal cells surrounding MM cells in bone marrow samples from patients with MM. Such treatments with Len was able to maintain the cytotoxic activity of the γδ T cells against MM cells in acidic conditions with lactic acid, and restored their anti-MM activity blunted in the presence of BMSCs. Interestingly, the expanded γδ T cells markedly suppressed the colony formation in semi-solid methylcellulose assays of RPMI8226 and KMS-11 cells [81±1 (mean ± SD) vs. 0±0 and 40±1 vs. 16±4 colonies/dish, respectively, p<0.01], and decreased in size their side populations, suggesting targeting a drug-resistant clonogenic MM cells. These results collectively demonstrate that Len and HMB-PP as well as Zol are an effective combination for ex vivo expansion of Th1-like γδ T cells with potent anti-MM activity, and suggest that Len in combination with Zol may maintain their in vivo anti-MM activity in the bone marrow where MM cells reside. The present results warrant further study on Len-based immunotherapy with γδ T cells. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Constitutive expression of pore-forming protein in peripheral blood gamma/delta T cells: implication for their cytotoxic role in vivo.

1990 ◽  
Vol 172 (6) ◽  
pp. 1877-1880 ◽  
Author(s):  
M Nakata ◽  
M J Smyth ◽  
Y Norihisa ◽  
A Kawasaki ◽  
Y Shinkai ◽  
...  
Keyword(s):  
T Cells ◽  
Cytotoxic Activity ◽  
Peripheral Blood ◽  
Human Peripheral Blood ◽  
Constitutive Expression ◽  
Immunocytochemical Staining ◽  
Target Cells ◽  
Gamma Delta T Cells ◽  
Gamma Delta

The cytotoxic activity and pore-forming protein (PFP) expression of human peripheral blood (PB) gamma/delta T cells were examined. Fresh gamma/delta T cells isolated from PB lymphocytes by fluorescence-activated cell sorting exhibited a substantial natural killer-like cytotoxic activity against K562 target cells and had a high cytotoxic potential triggered by anti-CD3 monoclonal antibody (mAb) against P815 target cells bearing Fc gamma R. Immunocytochemical staining with an anti-PFP mAb revealed that virtually all PB gamma/delta T cells are granular lymphocytes with abundant PFP in their cytoplasmic granules. Constitutive expression of PFP in PB gamma/delta T cells was also demonstrated by Northern blot analysis. These observations support the proposed role of gamma/delta T cells in cytolytic immune surveillance in vivo.

scholarly journals Potent ex vivo armed T cells using recombinant bispecific antibodies for adoptive immunotherapy with reduced cytokine release

2021 ◽  
Vol 9 (5) ◽  
pp. e002222
Author(s):  
Jeong A Park ◽  
Brian H Santich ◽  
Hong Xu ◽  
Lawrence G Lum ◽  
Nai-Kong V Cheung
Keyword(s):  
T Cells ◽  
T Cell ◽  
Ex Vivo ◽  
Γδ T Cells ◽  
Cell Number ◽  
Bispecific Antibodies ◽  
Treatment Schedule ◽  
Cytokine Release ◽  
Antitumor Activities

BackgroundT cell-based immunotherapies using chimeric antigen receptors (CAR) or bispecific antibodies (BsAb) have produced impressive responses in hematological malignancies. However, major hurdles remained, including cytokine release syndrome, neurotoxicity, on-target off-tumor effects, reliance on autologous T cells, and failure in most solid tumors. BsAb armed T cells offer a safe alternative.MethodsWe generated ex vivo armed T cells (EATs) using IgG-[L]-scFv-platformed BsAb, where the anti-CD3 (huOKT3) scFv was attached to the light chain of a tumor-binding IgG. BsAb density on EAT, in vitro cytotoxicity, cytokine release, in vivo trafficking into tumors, and their antitumor activities were evaluated in multiple cancer cell lines and patient-derived xenograft mouse models. The efficacy of EATs after cryopreservation was studied, and gamma delta (γδ) T cells were investigated as unrelated alternative effector T cells.ResultsThe antitumor potency of BsAb armed T cells was substantially improved using the IgG-[L]-scFv BsAb platform. When compared with separate BsAb and T cell injection, EATs released less TNF-α, and infiltrated tumors faster, while achieving robust antitumor responses. The in vivo potency of EAT therapy depended on BsAb dose for arming, EAT cell number per injection, total number of EAT doses, and treatment schedule intensity. The antitumor efficacy of EATs was preserved following cryopreservation, and EATs using γδ T cells were safe and as effective as αβ T cell-EATs.ConclusionsEATs exerted potent antitumor activities against a broad spectrum of human cancer targets with remarkable safety. The antitumor potency of EATs depended on BsAb dose, cell number and total dose, and schedule. EATs were equally effective after cryopreservation, and the feasibility of third-party γδ-EATs offered an alternative for autologous T cell sources.

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