Provision of rapid and specific ex vivo diagnosis of central nervous system lymphoma from rodent xenograft biopsies by a fluorescent aptamer.
Publication/Presentation Date
6-1-2021
Abstract
OBJECTIVE: Differentiating central nervous system (CNS) lymphoma from other intracranial malignancies remains a clinical challenge in surgical neuro-oncology. Advances in clinical fluorescence imaging contrast agents and devices may mitigate this challenge. Aptamers are a class of nanomolecules engineered to bind cellular targets with antibody-like specificity in a fraction of the staining time. Here, the authors determine if immediate ex vivo fluorescence imaging with a lymphoma-specific aptamer can rapidly and specifically diagnose xenografted orthotopic human CNS lymphoma at the time of biopsy.
METHODS: The authors synthesized a fluorescent CNS lymphoma-specific aptamer by conjugating a lymphoma-specific aptamer with Alexa Fluor 488 (TD05-488). They modified human U251 glioma cells and Ramos lymphoma cells with a lentivirus for constitutive expression of red fluorescent protein and implanted them intracranially into athymic nude mice. Three to 4 weeks postimplantation, acute slices (biopsies, n = 28) from the xenografts were collected, placed in aptamer solution, and imaged with a Zeiss fluorescence microscope. Three aptamer staining concentrations (0.3, 1.0, and 3.0 μM) and three staining times (5, 10, and 20 minutes) followed by a 1-minute wash were tested. A file of randomly selected images was distributed to neurosurgeons and neuropathologists, and their ability to distinguish CNS lymphoma from negative controls was assessed.
RESULTS: The three staining times and concentrations of TD05-488 were tested to determine the diagnostic accuracy of CNS lymphoma within a frozen section time frame. An 11-minute staining protocol with 1.0-μM TD05-488 was most efficient, labeling 77% of positive control lymphoma cells and less than 1% of negative control glioma cells (p < 0.001). This protocol permitted clinicians to positively identify all positive control lymphoma images without misdiagnosing negative control images from astrocytoma and normal brain.
CONCLUSIONS: Ex vivo fluorescence imaging is an emerging technique for generating rapid histopathological diagnoses. Ex vivo imaging with a novel aptamer-based fluorescent nanomolecule could provide an intraoperative tumor-specific diagnosis of CNS lymphoma within 11 minutes of biopsy. Neurosurgeons and neuropathologists interpreted images generated with this molecular probe with high sensitivity and specificity. Clinical application of TD05-488 may permit specific intraoperative diagnosis of CNS lymphoma in a fraction of the time required for antibody staining.
Volume
134
Issue
6
First Page
1783
Last Page
1790
ISSN
1933-0693
Published In/Presented At
Georges, J., Qi, X., Liu, X., Zhou, Y., Woolf, E. C., Valeri, A., Al-Atrache, Z., Belykh, E., Feuerstein, B. G., Preul, M., Scheck, A. C., Reiser, M., Anderson, T., Gopez, J., Appelt, D., Yocom, S., Eschbacher, J., Yan, H., & Nakaji, P. (2020). Provision of rapid and specific ex vivo diagnosis of central nervous system lymphoma from rodent xenograft biopsies by a fluorescent aptamer. Journal of neurosurgery, 134(6), 1783–1790. https://doi.org/10.3171/2020.4.JNS192476
Disciplines
Medicine and Health Sciences
PubMedID
32707545
Department(s)
Department of Surgery
Document Type
Article