30 research outputs found
Progressive multifocal leukoencephalopathy in patients treated with chimeric antigen receptor T cells
No full text: Using 2 global postmarketing surveillance databases, Goldman and colleagues report that progressive multifocal leukoencephalopathy (PML), a viral disease associated with profound immunosuppression, occurs in approximately 0.9 cases per 1000 recipients of CD19-directed CAR T-cell therapy. The risk of PML appears higher with CAR T-cell therapy than other cancer therapies, but its precise role cannot be distinguished from antecedent therapies that these patients receive
From Naturally Occurring Tumor Immunity to Supernatural T Cells: Isolation and Characterization of a Murine T Cell Receptor Specific for Human Breast and Ovarian Tumor Antigen Cdr2
No full textPatients with paraneoplastic cerebellar degeneration (PCD), a form of neuronal autoimmunity, have a co-occurring natural immune response against a protein called cdr2 in their breast and ovarian carcinomas, and thus provide an innovative starting point for understanding how to harness the immune system to fight cancer. We previously demonstrated cdr2-specific cytotoxic T lymphocytes (CTL) in the peripheral blood of HLA-A2.1+ PCD patients, suggesting that CTLs mediate tumor immunity in these patients. Cdr2 is expressed by a large proportion of breast and ovarian tumors from individuals who do not develop neurological disease, suggesting that immune responses to this antigen may develop independently of autoimmune responses. Here we explore establishing cdr2 as a target for breast and ovarian cancer immunotherapy by identifying naturally processed A2.1-restricted epitopes of cdr2. Immunization of A2.1 transgenic mice with recombinant adenovirus encoding human full length cdr2 led to the identification of two naturally processed A2.1-restricted human cdr2 peptides: cdr2(289-297) and cdr2(290-298). Mouse-derived A2.1-restricted cdr2(289-297)-specific CTLs were able to target cells expressing endogenous human cdr2, but also cross-reacted with endogenous mouse cdr2, resulting in partial tolerance to this epitope. In contrast, mouse-derived A2.1-restricted cdr2(290-298)-specific CTL were capable of recognizing tumor cells expressing endogenous human cdr2, but were unable to recognize mouse cdr2 due to nonhomology of the human and mouse cdr2(290- 298) epitopes. cdr2(290-298)-specific CTL clones were isolated, and their TCR gene cloned. Transfer of the mouse-derived TCR into human CD8+ T cells turned them into efficient cdr2-specific CTLs. We have detected CD8+ T cells specific for both cdr2(289-297) and cdr2(290-298) in peripheral blood from A2.1+ PCD patients by tetramer staining. This correlates the presence of T cells specific to these epitopes with PCD and effective anti-gynecologic tumor immunity, and suggests that these are bona fide tumor-associated CTL epitopes. We conclude swthat gene transfer of TCR specific for cdr2(290-298) could provide the basis for potent breast and ovarian cancer immunotherapies, while cdr2(289-297)-specific T cells, able to target both mouse and human cdr2, offer a platform for generating a humanized animal model to investigate the whether cdr2-TCR gene transfer is possible without inducing neuronal autoimmunity
How I treat unique and difficult-to-manage cases of CAR T-cell therapy–associated neurotoxicity
No full textWith growing indications for chimeric antigen receptor (CAR) T-cell therapy, toxicity profiles are evolving. There is an urgent and unmet need of approaches to optimally manage emerging adverse events that extend beyond the standard paradigm of cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome (ICANS). Although management guidelines exist for ICANS, there is little guidance on how to approach patients with neurologic comorbidities, and how to manage rare neurotoxicity presentations, such as CAR T-cell therapy-related cerebral edema, severe motor complications or late-onset neurotoxicity. In this study, we present 3 scenarios of patients treated with CAR T cells who develop unique types of neurotoxicity, and we describe an approach for the evaluation and management based on experience because objective data are limited. The goal of this study is to develop an awareness of emerging and unusual complications, discuss treatment approaches, and help institutions and health care providers establish frameworks to navigate how to best address unusual neurotoxicities to ultimately improve patient outcomes
Multifocal and pathologically-confirmed brain metastasis complete response to trastuzumab deruxtecan
No full textAntibody–drug conjugates have transformed the treatment of HER2+ breast and other cancers. Unfortunately, the CNS remains a sanctuary site for many such patients in part due to poor macromolecule penetration across the blood–brain tumor barrier. Trastuzumab deruxtecan (T-DXd), a high-payload antibody–drug conjugate, was recently found to improve progression-free survival in HER2+ breast cancer patients versus prior-generation trastuzumab emtansine, prompting us to evaluate CNS activity in a woman with brain-only metastatic disease. T-DXd achieved complete response despite heavy pretreatment. Three persistent, previously-irradiated lesions were biopsy-proven to represent treatment effect. Subsequent recurrence occurred upon treatment holiday; partial response was observed with rechallenge. This case suggests T-DXd is active in HER2+ breast cancer brain metastases and supports further prospective evaluation
Comparison of HuA p321-specific CD8+ T cells and HuD p321-specific CD8+ T cells.
No full text<p>(a) Sequences of HuD p321 and HuA p321 (b) RMA/S cells were incubated with serial dilutions of peptide and stained for D<sup>b</sup> MHC I. HuD p321 and HuA p321 were assayed. The A2.1 epitope of influenza (M1) was used as a negative control. The D<sup>b</sup> epitope of influenza (NP) was used as a positive control. (c) C57BL/6 mice were immunized with individual peptides (NP, HuA p321, or HuD p321) in TiterMax adjuvant (2 mice per group). 7 days later, draining lymph node CD8+ T cells were plated in an IFNγ ELISPOT assay (2×10<sup>5</sup>/well) with peptide pulsed EL4 cells (5×10<sup>4</sup>/well). The assay was performed in triplicate. Means are plotted and error bars represent standard deviations of the mean. Data is representative of four experiments.</p
Characterization of HuD p321-specific CD8+ T.
No full text<p>(a) 5×10<sup>6</sup> HuD p321-specific <i>in vitro</i> stimulated CD8+ T cells were adoptively transferred into Rag<sup>−/−</sup> mice (n = 2) with 2×10<sup>6</sup> C57BL/6 DC pulsed with p321. Mice also received PTx and IL-2. Eight days post transfer, mice were injected with CFSE-labeled syngeneic splenocytes pulsed with HuD p321 (CFSE<sup>hi</sup>) or βgal p96 (CFSE<sup>lo</sup>). A naïve control mouse without transferred CD8+ T cells was injected with CFSE-labeled splenocytes. 6 hours after target injection, splenocytes were analyzed by FACS for <i>in vivo</i> target cell lysis. A representative mouse is shown. Data is representative of two experiments. (b) C57BL/6 mice (n = 2) were used as recipients of adoptively transferred HuD p321-specific CD8+ T cells as in (a). A representative mouse is shown. Data is representative of two experiments. (c) Primary kidney cells from C57BL/6 mice (D<sup>b</sup>+/K<sup>b</sup>+) or transgenic Bm1 mice (D<sup>b</sup>+/K<sup>b</sup>−) were irradiated and pulsed with HuD p321 or βgal p96 and used as stimulators in an IFNγ ELIPOST assay (5×10<sup>4</sup>/well) with 3× restimulated HuD p321-specific or βgal p96-specific CD8+ T cells (10<sup>4</sup>/well). The assay was performed in triplicate. Means are plotted and error bars represent standard deviations of the mean. Data is representative of two experiments. (d) C57BL/6 mice were immunized with either AdVHuD or influenza virus or left untreated (2 mice per group). 15 days after immunization, CD8+ T cells were isolated from the spleen and stained directly <i>ex vivo</i> with anti-CD8+ antibody and PE-labeled tetramer. A portion of splenocytes from each mouse was stimulated <i>in vitro</i> with cognate peptide for 7 days. Naïve mice were stimulated with HuD p321. CD8+ T cells from <i>in vitro</i> stimulation cultures were stained with anti-CD8+ antibody and PE-labeled tetramer. Plots are gated on CD8+ T cells. Data is representative of two experiments.</p
C57BL/6 mice are tolerized to HuD.
No full text<p>(a) C57BL/6 mice were immunized with AdVHuD or AdVβgal+PTx (2 mice per group). 13 days later, CD8+ T cells were isolated from the spleen and plated in an IFNγ ELISPOT assay (2×10<sup>5</sup>/well) with EL4 pulsed with 10 uM peptide (5×10<sup>4</sup>/well). The assay was performed in triplicate. Means are plotted and error bars represent standard deviations of the mean. Data is representative of four experiments. (b) C57BL/6 mice were immunized with AdVHuD−/+PTx (2 mice per group). 13 days later, splenocytes were stimulated <i>in vitro</i> with 0.5 uM HuD p321. On day 7, CD8+ T cells were plated in an IFNγ ELISPOT assay (10<sup>4</sup>/well) with DC pulsed with 10 uM peptide (7×10<sup>3</sup>/well). The assay was performed in triplicate. Means are plotted and error bars represent standard deviations of the mean Data is representative of two experiments. (c) Individual HuD<sup>+/+</sup> or HuD<sup>−/−</sup> mice were immunized with AdVHuD+PTx and used in an IFNγ ELISPOT assay as described in (a). The assay was performed in triplicate. Means are plotted and error bars represent standard deviations of the mean. Data is representative of four experiments. (d) Half of the spleens from mice immunized in (c) were stimulated <i>in vitro</i> with HuD p321. After 7 days, CD8+ T cells were isolate from stimulation cultures and plated in an IFNγ ELISPOT (10<sup>4</sup>/well) with peptide pulsed EL4 cells (5×10<sup>4</sup>/well).</p
p321 is the immunodominant CD8+ T cell epitope of HuD.
No full text<p>(a) A representative peptide screen of 16 HuD peptides. Individual or duplicate C57BL/6 mice were immunized with a single HuD peptide emulsified in TiterMax adjuvant. 7 days later, CD8+ T cells were harvested from draining lymph nodes and plated in an IFNγ ELISPOT assay (2×10<sup>5</sup>/well) with EL4 cells pulsed with 10 uM cognate or irrelevant peptide (5×10<sup>4</sup>/well). The assay was performed in triplicate. Means are plotted and error bars represent standard deviations of the mean. Positive peptides were re-screened in triplicate mice. (b) 7 peptides (in bold) were identified as potential CD8+ epitopes from the HuD protein sequence. (c) C57BL/6 mice were immunized with AdVHuD plus PTx. 13 days after immunization, splenocytes were divided into 8 <i>in vitro</i> stimulation cultures and stimulated with each of the 7 HuD peptides or βgal p96. CD8+ T cells were purified from stimulation cultures and plated (10<sup>4</sup> T cells/well) with cognate or irrelevant peptide-pulsed irradiated EL4 cells (5×10<sup>4</sup>/well) in an IFNγ ELISPOT assay. The assay was performed in triplicate. Means are plotted and error bars represent standard deviations of the mean. Data is representative of three experiments. (d) As a control for <i>in vitro</i> priming, C57BL/6 mice were immunized with AdVβgal+PTx and stimulated <i>in vitro</i> with each of the 7 potential HuD epitopes or βgal p96 and assayed for IFNγ secretion as in (c).</p
