A conjoined universal helper epitope can unveil antitumor effects of a neoantigen vaccine targeting an MHC class I-restricted neoepitope.


Personalized cancer vaccines targeting neoantigens arising from somatic missense mutations are currently being evaluated for the treatment of various cancers due to their potential to elicit a multivalent, tumor-specific immune response. Several cancers express a low number of neoantigens; in these cases, ensuring the immunotherapeutic potential of each neoantigen-derived epitope (neoepitope) is crucial. In this study, we discovered that therapeutic vaccines targeting immunodominant major histocompatibility complex (MHC) I-restricted neoepitopes require a conjoined helper epitope in order to induce a cytotoxic, neoepitope-specific CD8+ T-cell response. Furthermore, we show that the universally immunogenic helper epitope P30 can fulfill this requisite helper function. Remarkably, conjoined P30 was able to unveil immune and antitumor responses to subdominant MHC I-restricted neoepitopes that were, otherwise, poorly immunogenic. Together, these data provide key insights into effective neoantigen vaccine design and demonstrate a translatable strategy using a universal helper epitope that can improve therapeutic responses to MHC I-restricted neoepitopes.






Published Version (Please cite this version)


Publication Info

Swartz, Adam M, Kendra L Congdon, Smita K Nair, Qi-Jing Li, James E Herndon, Carter M Suryadevara, Katherine A Riccione, Gary E Archer, et al. (2021). A conjoined universal helper epitope can unveil antitumor effects of a neoantigen vaccine targeting an MHC class I-restricted neoepitope. NPJ vaccines, 6(1). p. 12. 10.1038/s41541-020-00273-5 Retrieved from https://hdl.handle.net/10161/22510.

This is constructed from limited available data and may be imprecise. To cite this article, please review & use the official citation provided by the journal.



Smita K Nair

Professor in Surgery

I have 22 years of experience in the field of cancer vaccines and immunotherapy and I am an accomplished T cell immunologist. Laboratory website:

Current projects in the Nair Laboratory:
1] Dendritic cell vaccines using tumor-antigen encoding RNA (mRNA, total tumor RNA, amplified tumor mRNA)
2] Local immune receptor modulation using mRNA that encodes for antibodies, receptor-ligands, cytokines, chemokines and toll-like receptors (current target list: CTLA4, GITR, PD1, TIM3, LAG3, OX40 and 41BB)
3] Combination therapies for cancer: cytotoxic therapy (radiation, chemo and oncolytic poliovirus therapy) with dendritic cell-based vaccines and immune checkpoint blockade
4] Adoptive T cell therapy using tumor RNA-transfected dendritic cells to expand tumor-specific T cells ex vivo
5] Adoptive T cell therapy using PSMA CAR (chimeric antigen receptor) RNA-transfected T cells
6] Direct injection of tumor antigen encoding RNA (targeting antigens to dendric cells in vivo using nanoparticles and aptamers)


Qi-Jing Li

Adjunct Associate Professor in the Department of Immunology

Recent clinical success in cancer immunotherapy, including immune checkpoint blockades and chimeric antigen receptor T cells, have settled a long-debated question in the field: whether tumors can be recognized and eliminated by our own immune system, specifically, the T lymphocyte. Meanwhile, current limitations of these advanced treatments pinpoint fundamental knowledge deficits in basic T cell biology, especially in the context of tumor-carrying patients. Aiming to develop new immunotherapies against cancers, and interconnected with clinical trials executed by clinician collaborators and immunogenomic tools developed in house, my research program rests on three pillars – the T cell, the Tumor Microenvironment, and Immunotherapy.

We regard the tumor as an acquired immunosuppressive organ. By this scientific precept, we study how tumors inhibit T cell-mediated immunity both locally and systemically. Our early TCR repertoire profiling of gastric tumors and tumor-free patient mucosa revealed the correlation between tissue resident T cell diversity and patient survival. Our recent single cell RNA sequencing study depicted complex pathways to develop T cell memory intratumorally. Currently, aided by bioinformatics and animal models, we are actively dissecting signaling pathways, transcription regulatory networks, and epigenetic programs governing T cell differentiation in the tumor microenvironment. Moving beyond the local microenvironment, our previous studies also demonstrated that tumors remotely modulate T cell antigen-priming events in the spleen. This ongoing in-depth investigation has gradually unveiled the profound impact of this “tele-education”: established tumors hijack hematopoiesis to protect themselves against T cell surveillance. The next step is to identify those evil envoys sent out by tumors carrying signals for systemic immune suppression.

The expanding boundary of T cell biology is the frontier of cancer immunotherapy. The contrast between the unprecedented success of T cell-based therapies for blood malignancies and their repeated failures against solid tumors vividly highlights our prevalent challenges: to understand how T cells can infiltrate tumors; how infiltrated T cells can resist microenvironmental suppression; and how activated T cells can form persistent memory to restrict tumor development and metastasis. During the last decade, my laboratory invested heavily in the microRNA (miRNA) field, deeming miRNAs a unique tool for T cell biology discovery. Identifying miRNA functions and targets is our path to discovering novel proteins, or novel functions of known proteins, in T cell regulation. Expression profiling and functional screening in the lab have produced many candidates to make T cells smarter and stronger. Due to their size, these miRNA candidates can be easily combined with targeting moieties to armor T cells, and we have incorporated these small weaponries, and introduced genomic manipulations on their downstream targets, into CAR-T cells for pre-clinical studies. Indeed, some of them greatly enhance CAR-T’s anti-tumor function. As a general principle, we believe that it is necessary to empower transferred CAR T or TCR-T cells with enhanced functionality against solid tumors. We also believe the T cell is a perfect platform to integrate genomic engineering for combinatory cancer therapy. Currently, we are actively involved in three such armored CAR-T or TCR-T trials for various solid tumor treatments.  

Accompanying these trials, and other immunotherapies carried out by colleagues on campus and world-wide, we design and execute comprehensive immune monitoring procedures to rationalize successes and failures. Clinical observations are smoothly deconstructed into basic but intriguing T cell questions for us to answer, and answers generated on the bench directly inform T cell designs in future trials. This is our closed circle of research and day-to-day operation.


James Emmett Herndon

Professor of Biostatistics & Bioinformatics

Current research interests have application to the design and analysis of cancer clinical trials. Specifically, interests include the use of time-dependent covariables within survival models, the design of phase II cancer clinical trials which minimize some of the logistical problems associated with their conduct, and the analysis of longitudinal studies with informative censoring (in particular, quality of life studies of patients with advanced cancer).


John Howard Sampson

Robert H., M.D. and Gloria Wilkins Professor of Neurosurgery, in the School of Medicine

Current research activities involve the immunotherapeutic targeting of a tumor-specific mutation in the epidermal growth factor receptor. Approaches used to target this tumor-specific epitope include unarmed and radiolabeled antibody therapy and cell mediated approaches using peptide vaccines and dendritic cells. Another area of interest involves drug delivery to brain tumors. Translational and clinical work is carried out in this area to formulate the relationship between various direct intratumoral infusion parameters and drug distribution within brain tumors and normal brain.

The Duke Brain Tumor Immunotherapy Program (BTIP) has an emphasis on translational research in Neuro-Oncology. There are two main areas of study. The first is novel mechanisms of delivery of large molecular weight molecules, such as monoclonal antibodies, throughout brain intersitial space using novel intracerebral infusion techniques developed by this laboratory. Studies exploring this technology are undertaken in both small and large laboratory animals and patients with brain tumors.

The other focus of the BTIP is translational immunotherapy. In this line of work, dendritic cell vaccination strategies and adoptive T-cell strategies have been developed to target novel and well-characterized tumor-specific antigens in patients with brain tumors. The BTIP integrates well with and works closely with the Preston Robert Tisch Brain Tumor Center at Duke. The BTIP is well funded and currently holds seven NIH grants, including a SPORE in Brain Cancer grant. There are a large number of investigators at various levels so that students will get exposure to various levels of research and mentorship.

Unless otherwise indicated, scholarly articles published by Duke faculty members are made available here with a CC-BY-NC (Creative Commons Attribution Non-Commercial) license, as enabled by the Duke Open Access Policy. If you wish to use the materials in ways not already permitted under CC-BY-NC, please consult the copyright owner. Other materials are made available here through the author’s grant of a non-exclusive license to make their work openly accessible.