IMMUNE PROFILING UNCOVERS POTENT ADJUVANT CAPACITIES OF SARS-COV-2 INFECTION TO VACCINATION LEADING TO MEMORY T CELL RESPONSES WITH A TH17 SIGNATURE IN CANCER PATIENTS

It is unclear whether cancer patients show impaired responses to COVID-19 and vaccination. Immune profiling was performed in three cohorts of healthy donors and oncologic patients: infected with SARS CoV-2, BNT162b2-vaccinated, and with previous COVID-19 and subsequently vaccinated. Vaccination was a poor inductor of T cell responses compared to infection, which significantly potentiated vaccination in antibody and T cell responses. T cell major targets in natural infection were the M and S protein, but not the N protein. T cell responses quickly decayed after 6 months post-vaccination, and T cell profiling showed that vaccination expanded effector T cells rather than memory T cell subsets unless the subjects had previous COVID-19. Cancer patients with previous COVID-19 and vaccinated exhibited potent IL-17+ CD4 and CD8 responses and increased neutrophils. Concluding, COVID-19 infection had potent adjuvant effects for vaccination leading to memory T cell differentiation, but with enhanced IL-17 inflammation signatures.