Article Text

Download PDFPDF

580 Mapping interstitial fluid flow in the brain to improve CAR T cell trafficking and efficacy
  1. Margarita Gutova1,
  2. Ryan Woodall1,
  3. Eric Ma2,
  4. Cora Esparza3,
  5. Vanessa Salvary2,
  6. Brenda Aguilar2,
  7. Renate Starr2,
  8. Behnam Badie2,
  9. Darya Alizadeh2,
  10. Jennifer M Munson3,
  11. Russell C Rockne1 and
  12. Christine Brown1,2
  1. 1Beckman Research Institute, City of Hope, Duarte, CA, USA
  2. 2City of Hope Medical Center, Duarte, CA, USA
  3. 3Fralin Biomedical Research Institute, Virginia Tech, Roanoke, VA, USA
  • Journal for ImmunoTherapy of Cancer (JITC) preprint. The copyright holder for this preprint are the authors/funders, who have granted JITC permission to display the preprint. All rights reserved. No reuse allowed without permission.


Background A major obstacle to successful CAR T cell therapy for glioblastoma (GBM) is effective tumor trafficking and infiltration, which is limited by the blood-brain and blood-CSF barriers. Further, the GBM tumor microenvironment (TME) is characterized by solid stress, vessel leakiness, hypoxia, low pH, and high interstitial fluid pressure, all which impact CAR T cell trafficking. In this study, we set out to address two clinical challenges related to CAR T cell trafficking and efficacy: 1) the detection of CAR T cell tumor infiltration and bioactivity using clinical translatable imaging techniques, such as advanced MRI; and 2) the optimization of the route of administration of CAR T-cells for improved trafficking and therapeutic effect.

Methods We are evaluating CAR T-cells as a novel cell-based immunotherapy for treating glioblastoma (GBM) in early phase clinical trials. CAR T-cell therapy has been shown to induce complete regression in at least one case (Brown et al. 2016). These results have led to the initiation of a first-in-human phase I CAR T-cell trial for recurrent high-grade glioma patients at City of Hope (NCT02208362). In this study, perfusion imaging was performed on a subset of patients who received MRI pre-treatment and post-resection, and follow-up MRI after 3 treatment cycles roughly one month after initial imaging (n = 41).

Results A decrease in MR-observed tumor volume was significantly correlated to a decrease in contrast leakage into the surrounding tissue (r = 0.369, p = 0.0177*). These results suggest preliminary evidence of vascular normalization in patients who had strong initial response to CAR-T therapy. Immunohistochemistry analysis of patient tumor tissue indicates that endogenous human T cells were distributed around CD31 stained blood vessels (surgical sample analysis of CAR T patients). To better understand how perfusion imaging relates to CAR T cell therapy, we used two syngeneic models of glioma, K-luc and GL261, and characterized fluid flow dynamics during tumor response versus progression, comparing both invasive (K-luc) versus bulky (GL261) tumor growth phenotypes. We also characterized endogenous immune cell subset distribution at the tumor edge and tumor center, such as T cells (CD3, CD4 and CD8), macrophages (CD68 and CD163) and tumor biomarkers-VEGFA, VEGFC, CD31, HIF1a by immunohistochemistry, which were changing with perfusion-diffusion kinetics of the tumor.

Conclusions Ongoing studies are focused on further investigating interstitial fluid flow as an imaging biomarker predictive of response both clinically and pre-clinically.

This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.