ABSTRACT
Gene-mediated cytotoxic immunotherapy (GMCI) is an immune strategy implemented through local delivery of an adenovirus-based vector expressing the thymidine kinase gene (aglatimagene besadenovec, AdV-tk) followed by anti-herpetic prodrug valacyclovir. A phase I dose escalation trial of GMCI followed by chemotherapy was conducted in patients with malignant pleural effusion (MPE). AdV-tk was administered intrapleurally (IP) in three cohorts at a dose of 1 × 1012 to 1013 vector particles. Primary endpoint was safety; secondary endpoints included response rate, progression-free survival, and overall survival. Nineteen patients were enrolled: median age 67 years; 14 with malignant mesothelioma, 4 non-small-cell lung cancer (NSCLC), and 1 breast cancer. There were no dose limiting toxicities. All 3 patients in cohort 2 experienced transient cytokine release syndrome (CRS). Addition of celecoxib in cohort 3 reduced the incidence and severity of CRS (none > grade 2). Three patients are alive (23-33 months after GMCI), and 3 of 4 NSCLC patients had prolonged disease stabilization; one is alive 29 months after GMCI, 3.6 years after initial diagnosis. GMCI was safe and well tolerated in combination with chemotherapy in patients with MPE and showed encouraging response. Further studies are warranted to determine efficacy.
Subject(s)
Genetic Therapy , Immunotherapy , Pleural Effusion, Malignant/immunology , Pleural Effusion, Malignant/therapy , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Cytotoxic/metabolism , Adenoviridae/genetics , Aged , Aged, 80 and over , Biomarkers , Combined Modality Therapy , Female , Genetic Therapy/adverse effects , Genetic Therapy/methods , Genetic Vectors/genetics , Humans , Immunotherapy/adverse effects , Immunotherapy/methods , Male , Middle Aged , Pleural Effusion, Malignant/diagnosis , Pleural Effusion, Malignant/metabolism , Positron Emission Tomography Computed Tomography , Respiratory Function Tests , Treatment OutcomeABSTRACT
Several studies have shown that conformational changes of ß(2)-glycoprotein I (ß(2)GPI) when bound to negatively charged components expose cryptic epitopes and subsequent binding of anti-ß(2)GPI from patients with antiphospholipid syndrome (APS). However, the role of the carbohydrate chains of ß(2)GPI in this anti-ß(2)GPI reactivity is poorly understood. We therefore studied the reactivity and inhibition of anti-ß(2)GPI antibodies from APS patients with native, partially glycosylated ß(2)GPI (pdß(2)GPI; without sialic acid) and completely deglycosylated ß(2)GPI (cdß(2)GPI). To determine the potential biologic importance of these glycoforms and their interaction with anti-ß(2)GPI in vitro, stimulation assays were performed with the U937 cell line. Circular dichroism (CD) and fluorescence analysis of the three ß(2)GPI forms were also studied. We found an increased reactivity of anti-ß(2)GPI against pdß(2)GPI and cdß(2)GPI compared to native ß(2)GPI. Both deglycosylated ß(2)GPI isoforms showed higher inhibition of the anti-ß(2)GPI reactivity than the native protein in soluble-phase. Likewise, the antibody/ß(2)GPI/glycoform complexes increased the synthesis of IL-6, IFNγ and TNFα and the expression of HLA-DR, CD14 and CD11c in U937 cells. CD and fluorescence studies of the glycoforms yielded considerable changes in the fluorescence signals. Our work suggests that the partial or complete removal of the carbohydrate chains uncover cryptic epitopes present in ß(2)GPI. The differentiation and increased synthesis of pro-inflammatory cytokines by U937 cells in vitro may have pathogenetic implications.
