Expression of CD56 in glioblastoma treated with NK cell immunotherapy

Madelynn J Gaines, Yeonhee H Yun, PhD, Michael C Veronesi, MD, PhD, George E Sandusky, DVM, PhD, Departments of Pathology and Radiology & Imaging Sciences, Indiana University School of Medicine, 550 N University Blvd, Indianapolis IN 46202

Glioblastoma (GBM) is a rare and aggressive brain tumor with a life expectancy around 14 months. Immunotherapy is a novel approach to fighting cancers that have poor results with chemotherapy, such as GBMs. Natural killer (NK) cells are of great interest for immunotherapy because they are innate cells that do not require prior sensitization in order to induce apoptosis in cancer cells. There are two subtypes of NK cells: CD56bright and CD56dim. CD56dim NK cells are the more abundant and cytotoxic subtype. In this study, NK cell therapy was administered intravenously to a GBM mouse model. Radiological analysis included multimodal imaging using MRI T1CE, T2, and 18F-FET PET images to measure tumor volume. All methods showed a lower GBM volume with treatment when compared to control, and T1CE showed statistical significance (p<0.01). Histological analysis was done to determine the location of NK cells and to identify tumor infiltration; CD56 immunohistochemistry was used to visualize the subtypes of NK cells. Digital images of the slides were generated using Aperio ScanScope. Image analysis involved the development of a cytonuclear algorithm using Indica Labs HALO software to recognize staining intensity and quantify cells positive for CD56 expression. Our findings included a higher number of weakly stained cells in the NK therapy group than the control group, which may suggest the presence CD56dim NK cells in the GBM. However, we cannot confirm the presence of NK cells due to nonspecific staining throughout the tumor.

Additional Abstract Information

Presenter: Madelynn Gaines

Institution: Indiana University School of Medicine

Type: Poster

Subject: Biology

Status: Approved

Time and Location

Session: Poster 2
Date/Time: Mon 3:00pm-4:00pm
Session Number: 2644