PROJECT SUMMARY
This multi-PI proposal titled “SARS-CoV-2-reactive
subjects” is written in response to ‘RFA-CA-20-039’ -
tissue-resident memory T cells in healthy and cancer
Research projects in SARS-CoV-2 Serological Sciences.
Recent studies have shown that antibody responses to SARS-CoV-2 infection decline rapidly over time, implying
a lack of durable protective humoral (B cell) immunity. Whether this is also true for cellular immunity (e.g., T
cells) is poorly understood. It is well established that CD8+ TRM cells are the first line of defense in viral infections
at mucosal/barrier sites. They are also known to protect hosts against homologous or heterologous re-infections.
Our group was the first to show that TRM cells are pivotal players in driving effective anti-tumor immune responses
in lung cancer, and that TRM cells are the primary cellular targets of anti-PD1 therapies. These key findings were
possible because of the ongoing collaboration between Dr. Vijayanand, Dr. Ay, and Dr. Ottensmeier (Multi-PI).
This team brings together experience in T cell immunology, single-cell genomics, bioinformatics, and cancer
immunology. Our Multi-PI team has recently performed the first and largest single-cell RNA-seq and TCR-seq
analysis of SARS-CoV-2-reactive CD8+ and CD4+ T cells (~300,000 single-cells) from COVID-19 patients. Here,
to understand TRM responses to SARS-CoV-2, we will capitalize on a cohort of cancer (n=100) and non-cancer
(n=100) patients, who will provide excess airway (nasal, oropharynx, larynx), lung and tumor tissue specimens
obtained during routine surgery. In AIM 1, we will define the properties of SARS-CoV-2 reactive TRM cells from
cancer and non-cancer patients with or without previous SARS-CoV-2 infection. We will perform combined
single-cell RNA-seq and TCR-seq analysis of CD8+ TRM cells in the airways (nasal, oropharynx), lung, and tumor
tissue. In parallel, by stimulating PBMCs with SARS-CoV-2 peptide pool, we will determine the transcriptomic
and TCR sequence of SARS-CoV-2 reactive T cells. We will utilize this TCR sequence information to define the
numbers and properties of SARS-CoV-2 reactive-TRM cells in mucosal and tumor tissues. Recent studies in non-
exposed individuals (pre-COVID-19 pandemic) indicate pre-existing, circulating CD8+ T cells, with human
coronavirus cross-reactivity. Here, we will measure the quantity and quality of pre-existing SARS-CoV-2 cross-
reactive TRM responses in subjects without clinical or serological evidence of previous SARS-CoV-2 infection. In
AIM 2, we will assess the impact of SARS-CoV-2 infection on anti-tumor and other anti-viral TRM responses. We
will stimulate matched PBMCs (as above) with peptide pools targeting (i) common respiratory RNA viruses
(influenza (FLU), RSV), (ii) persistent DNA viruses (CMV, EBV), and (iii) a tumor-driving virus (HPV) to define
the TCR sequence of the respective virus-specific and tumor(HPV)-specific CD8+ T cells; we will utilize the TCR
information to determine frequency and properties of other virus/tumor-reactive TRM cells in mucosal and tumor-
tissue cells.