Naïve T cells and regulatory T cells, when purified, do not proliferate to the γ-cytokines IL-2, IL-7, or IL-15, despite their expression of cognate cytokine receptors. Dendritic cells (DCs) enabled the T cell proliferation to these cytokines, through cell-to-cell contact, but independent of T cell receptor stimulation. This effect lasted after separation of T cells from DCs, enabling enhanced proliferation of the T cells in DC-depleted hosts.
View Article and Find Full Text PDFInterleukin-15 (IL-15) monotherapy substantially increases the number and activity of natural killer (NK) cells and CD8+ T cells but has not produced clinical responses. In a xenograft mouse model, IL-15 enhanced the NK cell-mediated antibody-dependent cell cytotoxicity (ADCC) of the anti-CD52 antibody alemtuzumab and led to significantly more durable responses than alemtuzumab alone. To evaluate whether IL-15 potentiates ADCC in humans, we conducted a phase 1 single-center study of recombinant human IL-15 and alemtuzumab in patients with CD52-positive mature T-cell malignances.
View Article and Find Full Text PDFAdult T-cell leukemia/lymphoma (ATL) is an aggressive T-cell lymphoproliferative malignancy caused by human T-cell leukemia virus type 1 (HTLV-1). ATL is an orphan disease with no curative drug treatment regimens urgently needing new combination therapy. HTLV-1-infected cells rely on viral proteins, Tax and HBZ (HTLV-1-b-ZIP factor), to activate the transcription of various host genes that are critical for promoting leukemic transformation.
View Article and Find Full Text PDFAdult T-cell leukemia/lymphoma (ATLL) is an aggressive T-cell malignancy with a poor prognosis with current therapy. Here we report genome-wide CRISPR-Cas9 screening of ATLL models, which identified CDK6, CCND2, BATF3, JUNB, STAT3, and IL10RB as genes that are essential for the proliferation and/or survival of ATLL cells. As a single agent, the CDK6 inhibitor palbociclib induced cell cycle arrest and apoptosis in ATLL models with wild-type TP53.
View Article and Find Full Text PDFJ Immunother Cancer
April 2021
Background: Full application of cytokines as oncoimmunotherapeutics requires identification of optimal regimens. Our initial effort with intravenous bolus recombinant human interleukin-15 (rhIL-15) was limited by postinfusional reactions. Subcutaneous injection and continuous intravenous infusion for 10 days (CIV-10) provided rhIL-15 with less toxicity with CIV-10 giving the best increases in CD8 lymphocytes and natural killer (NK) cells.
View Article and Find Full Text PDFAdult T-cell leukemia (ATL) is an aggressive T-cell lymphoproliferative malignancy of regulatory T lymphocytes (Tregs), caused by human T-cell lymphotropic virus 1 (HTLV-1). Interleukin 2 receptor alpha (IL-2Rα) is expressed in the leukemic cells of smoldering/chronic ATL patients, leading to constitutive activation of the JAK/STAT pathway and spontaneous proliferation. The PI3K/AKT/mTOR pathway also plays a critical role in ATL cell survival and proliferation.
View Article and Find Full Text PDFDespite advances in therapy of Hodgkin's lymphoma (HL), a proportion of patients will not respond or relapse. The authors had previously identified CD25, IL-2Rα, as a target for systemic radioimmunotherapy of HL since most normal cells do not express CD25, but it is expressed by a minority of Hodgkin/Reed-Sternberg (HRS) cells and most Tregs rosetting around HRS cells. This was a single institution, nonrandomized, open-label phase I/II trial of radiolabeled Y-daclizumab, an anti-CD25 monoclonal antibody, BEAM (carmustine, etoposide, cytarabine, and melphalan) conditioning treatment followed by autologous hematopoietic stem cell transplant (ASCT).
View Article and Find Full Text PDFObjective: Human T cell lymphotropic virus 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic, progressive, neurological disease. Chronic activation of CD8 T cells, as evidenced by increased spontaneous lymphoproliferation and HTLV-1-specific cytotoxic T cells, has been demonstrated in HAM/TSP patients. Since IL-2 and IL-15 stimulate memory CD8 T cell activity, these cytokines have been implicated in the immunopathogenesis of HAM/TSP.
View Article and Find Full Text PDFPurpose: The first-in-human clinical trial with human bolus intravenous infusion IL15 (rhIL15) was limited by treatment-associated toxicity. Here, we report toxicity, immunomodulation, and clinical activity of rhIL15 administered as a 10-day continuous intravenous infusion (CIV) to patients with cancers in a phase I trial.
Patients And Methods: Patients received treatment for 10 days with CIV rhIL15 in doses of 0.
Adult T cell leukemia/lymphoma (ATLL) is a frequently incurable disease associated with the human lymphotropic virus type I (HTLV-I). RNAi screening of ATLL lines revealed that their proliferation depends on BATF3 and IRF4, which cooperatively drive ATLL-specific gene expression. HBZ, the only HTLV-I encoded transcription factor that is expressed in all ATLL cases, binds to an ATLL-specific BATF3 super-enhancer and thereby regulates the expression of BATF3 and its downstream targets, including MYC.
View Article and Find Full Text PDFThe cytokine IL15 is required for survival and activation of natural killer (NK) cells as well as expansion of NK-cell populations. Here, we compare the effects of continuous IL15 infusions on NK-cell subpopulations in cancer patients. Infusions affected the CD56 NK-cell subpopulation in that the expansion rates exceeded those of CD56 NK-cell populations with a 350-fold increase in their total cell numbers compared with 20-fold expansion for the CD56 subset.
View Article and Find Full Text PDFDespite significant advances in the treatment of Hodgkin's lymphoma (HL), a significant proportion of patients will not respond or will subsequently relapse. We identified CD25, the IL-2 receptor alpha subunit, as a favorable target for systemic radioimmunotherapy of HL. The scientific basis for the clinical trial was that, although most normal cells with exception of Treg cells do not express CD25, it is expressed by a minority of Reed-Sternberg cells and by most polyclonal T cells rosetting around Reed-Sternberg cells.
View Article and Find Full Text PDFPurpose: Interleukin-15 (IL-15) has significant potential in cancer immunotherapy as an activator of antitumor CD8 T and natural killer (NK) cells. The primary objectives of this trial were to determine safety, adverse event profile, dose-limiting toxicity, and maximum-tolerated dose of recombinant human IL-15 (rhIL-15) administered as a daily intravenous bolus infusion for 12 consecutive days in patients with metastatic malignancy.
Patients And Methods: We performed a first in-human trial of Escherichia coli-produced rhIL-15.
In the present study, Hu-Mikβ1, a humanized mAb directed at the shared IL-2/IL-15Rβ subunit (CD122) was evaluated in patients with T-cell large granular lymphocytic (T-LGL) leukemia. Hu-Mikβ1 blocked the trans presentation of IL-15 to T cells expressing IL-2/IL-15Rβ and the common γ-chain (CD132), but did not block IL-15 action in cells that expressed the heterotrimeric IL-15 receptor in cis. There was no significant toxicity associated with Hu-Mikβ1 administration in patients with T-LGL leukemia, but no major clinical responses were observed.
View Article and Find Full Text PDFThe superior sensitivity and specificity associated with the use of molecular assays has greatly improved the field of infectious disease diagnostics by providing clinicians with results that are both accurate and rapidly obtained. Herein, we review molecularly based infectious disease diagnostic tests that are Food and Drug Administration approved or cleared and commercially available in the United States as of December 31, 2010. We describe specific assays and their performance, as stated in the Food and Drug Administration's Summary of Safety and Effectiveness Data or the Office of In Vitro Diagnostic Device Evaluation and Safety's decision summaries, product inserts, or peer-reviewed literature.
View Article and Find Full Text PDFIL-15 uses the heterotrimeric receptor IL-2/IL-15Rβ and the γ chain shared with IL-2 and the cytokine-specific IL-15Rα. Although IL-15 shares actions with IL-2 that include activation of natural killer (NK) and CD8 T cells, IL-15 is not associated with capillary leak syndrome, activation-induced cell death, or with a major effect on the number of functional regulatory T cells. To prepare for human trials to determine whether IL-15 is superior to IL-2 in cancer therapy, recombinant human IL-15 (rhIL-15) was produced under current good manufacturing practices.
View Article and Find Full Text PDFThe retrovirus, human T-cell-lymphotrophic virus-1 (HTLV-I) is the etiologic agent of adult T-cell leukemia (ATL) and the neurological disorder HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The HTLV-I-encoded protein tax constitutively activates interleukin-2 (IL-2), IL-9, and IL-15 autocrine/paracrine systems that in turn activate the Jak3 (Janus kinase 3)/STAT5 (signal transducers and activators of transcription 5) pathway, suggesting a therapeutic strategy that involves targeting Jak3. We evaluated the action of the Jak3 inhibitor CP-690,550 on cytokine dependent ex vivo proliferation that is characteristic of peripheral blood mononuclear cells (PBMCs) from select patients with smoldering or chronic subtypes of ATL, or from those with HAM/TSP whose PBMCs are associated with autocrine/paracrine pathways that involve the production of IL-2, IL-9, IL-15, and their receptors.
View Article and Find Full Text PDFAdult T-cell leukemia (ATL), a heterogeneous disease, can be divided into smoldering, chronic, lymphoma, and acute types clinically. In addition to different clinical manifestations, different stages of ATL have different molecular signatures. Here, we demonstrated that smoldering/chronic ATL peripheral blood mononuclear cells spontaneously proliferated ex vivo in a cytokine (interleukin-12 [IL-12]/IL-9/IL-15)-dependent manner, while acute-type ATL peripheral blood mononuclear cells did not proliferate or proliferated independent of cytokines.
View Article and Find Full Text PDFThe etiologic agent of adult T-cell leukemia (ATL) is human T cell lymphotropic virus type I (HTLV-I). The HTLV-I protein Tax alters gene expression, including those of cytokines and their receptors, which plays an important role in early stages of ATL. Here we demonstrate that expression of interleukin-9 (IL-9) is activated by Tax via an NF-kappaB motif in its proximal promoter, whereas IL-9 receptor-alpha (IL-9Ralpha) expression is not induced by Tax.
View Article and Find Full Text PDFTwelve patients with T cell large granular lymphocyte leukemia and associated hematocytopenia were treated in a phase I dose-escalation trial with the murine monoclonal antibody Mikbeta1. Mikbeta1 identifies CD122, the beta-subunit shared by the IL-2 and IL-15 receptors. At the doses administered in this study the antibody inhibited the actions of IL-15 on both natural killer and T cells and that of IL-2 when the intermediate-affinity IL-2 receptor was expressed.
View Article and Find Full Text PDFPleomorphic lobular carcinoma of the breast is a variant of infiltrating lobular carcinoma that has poor prognosis. The pleomorphic appearance of this variant hinders its correct identification and differentiation from ductal carcinoma. The analysis of E-cadherin glycoprotein expression is a powerful tool for distinguishing lobular from ductal carcinomas, because complete loss of E-cadherin expression occurs in most infiltrating lobular tumors and lobular carcinomas in situ, but not in ductal tumors.
View Article and Find Full Text PDFLittle is known about the genetic alterations that occur during the progression of thyroid neoplasms. To understand better the biology of thyroid tumors, we investigated several genetic loci in benign and malignant thyroid neoplasms. Forty-one thyroid tumors (6 adenomas, 16 papillary, 14 follicular, and 5 anaplastic carcinomas) were studied.
View Article and Find Full Text PDFBenign conditions of the parathyroid gland have been classified as adenomas and hyperplasias. These entities however are difficult to distinguish when only a single gland is enlarged. Adenomas are defined as neoplastic clonal growths whereas hyperplasias are considered to be reactive processes of polyclonal origin.
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