Author(s)

Stefanie Sonnleitner^1*, Sissy Therese Sonnleitner^1,2*, Simone Obererlacher¹, Gernot Walder^1,2#

¹Dr. Gernot Walder GmbH, Medical Laboratory, Department of Virology, Ausservillgraten, Austria.
²Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria.

Background: The roll-out of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was certainly among the fastest in medical history. Vaccination campaigns around the world began a year after the outbreak in 2019. When Austria started vaccinating the population in 2020, we took the opportunity to collect data from the first sets of patients receiving the vaccine in our study region of East Tyrol. Purpose: Many studies have been conducted examining the immunogenicity of the new vaccines using classic serological test methods in combination with an IFN-γ ELISpot. Undeniable disadvantages of using IFN-γ to characterize the status of the cellular immunity are that 1) being an acute phase cytokine, IFN-γ loses signal strength in the long run and 2) IFN-γ does not provide information about the involvement of T helper 2 (Th2) cells in the immune process. This implies that it can affect false negative data about the cell-mediated immune status. Method: Therefore, in addition to a chemiluminescent immunoassay and the enzymatic IFN-γ ELISpot, this study included a fluorescent ELISpot assay using precoated human SARS-CoV-2-specific IFN-γ/IL-2/IL-5 ELISpot kits to show a more holistic overview on the involvement of T helper 1 (Th1) cells as signal senders of IL-2 and Th2 cells as senders of IL-5. Results and Conclusion: Our study confirms good immunogenicity of Pfizer/BioNTech BNT162b2 COVID-19 (Comirnaty) with strong Th1 and vanishingly small Th2 participation. The fluorescent three color iSpot can improve the diagnostic results’ significance for the individual, especially when the infection has been longer in the past and the IFN-γ signal diminishes.

Three-Color iSpot, Immune Response, Vaccination

Sonnleitner, S. , Sonnleitner, S. , Obererlacher, S. and Walder, G. (2023) Comparison of Pfizer/BioNTech BNT162b2 COVID-19 (Comirnaty) Vaccination Effects in Aged Adults with Special Consideration for the Effectiveness of the Three-Color iSpot in Assessing Immune Response. Journal of Biosciences and Medicines, 11, 111-123. doi: 10.4236/jbm.2023.115007.