Johns Hopkins Medicine researchers have launched a public, web-based atlas containing mass cytometry profiles from patients with metastatic pancreatic cancer. This initiative aims to provide a resource for scientists to study immune system responses to various combinations of vaccines and immune checkpoint inhibitor drugs, with the goal of accelerating the development of new therapies for pancreatic cancer.
Atlas Overview and Content
The atlas compiles information from 260 mass cytometry profiles, which detail markers on immune cells. These profiles were obtained from blood samples of 64 patients who participated in three clinical trials. These trials evaluated different combinations of two pancreatic cancer vaccines and two checkpoint inhibitors.
The platform utilizes over 40 protein-level markers to profile the immune system. It also includes data from before and after treatment to facilitate understanding of how cancer treatments induce longitudinal changes in the immune system. Researchers plan to expand the atlas with additional data, including information from tumor tissue analyses.
Accessibility and Collaboration
A description of the atlas was published in the January 12 issue of Cancer Immunology Research. The resource is publicly accessible online via SciServer (sciserver.org/datasets/biomed/cytof_atlas). It provides fully annotated cytometry data with a user interface and integrated tools designed to simplify comparisons of cell types and expression levels.
Further data, including raw protein expression, is available on Zenodo (doi.org/10.5281/zenodo.13937090), and analysis code is on the GitHub repository (github.com/wjhlab/Immunotherapy-Atlas).
This project was developed in collaboration with the Institute for Data Intensive Engineering and Science at Johns Hopkins. Dr. Won Jin Ho, an associate professor of oncology at Johns Hopkins, stated that the initiative was motivated by the lethality of pancreatic cancer, which has a five-year survival rate of 13%.
Companion Study Findings
In the same journal issue, Dr. Ho and colleagues also published results from a new phase II study. This trial involved 57 patients with metastatic pancreatic cancer whose disease had progressed on chemotherapy. Patients were randomized to receive the vaccine CRS-207 along with the immunotherapies anti-PD1 nivolumab and anti-CTLA4 ipilimumab, either with or without the GVAX vaccine, over six 21-day cycles.
Immunologic studies from this companion trial observed that vaccine-based regimens could generate T-cell clones specific to the antigens mesothelin and KRAS, and these clones successfully infiltrated tumors. The addition of anti-CTLA4 to the immunotherapy backbone was identified as a significant factor for increasing the infiltration of antigen-experienced T cells.
The research received support from various grants, including from the Lustgarten Foundation for Pancreatic Cancer Research and the National Institutes of Health.