Comparison of the Development of SARS-Coronavirus-2-Specific Cellular Immunity, and Central Memory CD4+ T-Cell Responses Following Infection versus Vaccination
Kevin M. Dennehy,
Eva Löll,
Christine Dhillon,
Johanna-Maria Classen,
Tobias D. Warm,
Lukas Schuierer,
Alexander Hyhlik-Dürr,
Christoph Römmele,
Yvonne Gosslau,
Elisabeth Kling,
Reinhard Hoffmann
Affiliations
Kevin M. Dennehy
Institute for Laboratory Medicine and Microbiology, Medical Faculty, University Hospital Augsburg, 86156 Augsburg, Germany
Eva Löll
Institute for Laboratory Medicine and Microbiology, Medical Faculty, University Hospital Augsburg, 86156 Augsburg, Germany
Christine Dhillon
Department of Pathology, Medical Faculty, University Hospital Augsburg, 86156 Augsburg, Germany
Johanna-Maria Classen
Internal Medicine III-Gastroenterology and Infectious Diseases, Medical Faculty, University Hospital Augsburg, 86156 Augsburg, Germany
Tobias D. Warm
Clinic for Vascular Surgery, Medical Faculty, University Hospital Augsburg, 86156 Augsburg, Germany
Lukas Schuierer
Institute for Laboratory Medicine and Microbiology, Medical Faculty, University Hospital Augsburg, 86156 Augsburg, Germany
Alexander Hyhlik-Dürr
Clinic for Vascular Surgery, Medical Faculty, University Hospital Augsburg, 86156 Augsburg, Germany
Christoph Römmele
Internal Medicine III-Gastroenterology and Infectious Diseases, Medical Faculty, University Hospital Augsburg, 86156 Augsburg, Germany
Yvonne Gosslau
Clinic for Vascular Surgery, Medical Faculty, University Hospital Augsburg, 86156 Augsburg, Germany
Elisabeth Kling
Institute for Laboratory Medicine and Microbiology, Medical Faculty, University Hospital Augsburg, 86156 Augsburg, Germany
Reinhard Hoffmann
Institute for Laboratory Medicine and Microbiology, Medical Faculty, University Hospital Augsburg, 86156 Augsburg, Germany
Memory T-cell responses following infection with coronaviruses are reportedly long-lived and provide long-term protection against severe disease. Whether vaccination induces similar long-lived responses is not yet clear since, to date, there are limited data comparing memory CD4+ T-cell responses induced after SARS-CoV-2 infection versus following vaccination with BioNTech/Pfizer BNT162b2. We compared T-cell immune responses over time after infection or vaccination using ELISpot, and memory CD4+ T-cell responses three months after infection/vaccination using activation-induced marker flow cytometric assays. Levels of cytokine-producing T-cells were remarkably stable between three and twelve months after infection, and were comparable to IFNγ+ and IFNγ+IL-2+ T-cell responses but lower than IL-2+ T-cell responses at three months after vaccination. Consistent with this finding, vaccination and infection elicited comparable levels of SARS-CoV-2 specific CD4+ T-cells after three months in addition to comparable proportions of specific central memory CD4+ T-cells. By contrast, the proportions of specific effector memory CD4+ T-cells were significantly lower, whereas specific effector CD4+ T-cells were higher after infection than after vaccination. Our results suggest that T-cell responses—as measured by cytokine expression—and the frequencies of SARS-CoV-2-specific central memory CD4+T-cells—indicative of the formation of the long-lived memory T-cell compartment—are comparably induced after infection and vaccination.
