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 t...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.展开更多
Since its outbreak in 2019,Severe Acute Respiratory Syndrome Coronavirus 2(SARS-Co V-2)keeps surprising the medical community by evolving diverse immune escape mutations in a rapid and effective manner.To gain deeper ...Since its outbreak in 2019,Severe Acute Respiratory Syndrome Coronavirus 2(SARS-Co V-2)keeps surprising the medical community by evolving diverse immune escape mutations in a rapid and effective manner.To gain deeper insight into mutation frequency and dynamics,we isolated ten ancestral strains of SARS-Co V-2 and performed consecutive serial incubation in ten replications in a suitable and common cell line and subsequently analysed them using RT-q PCR and whole genome sequencing.Along those lines we hoped to gain fundamental insights into the evolutionary capacity of SARS-Co V-2 in vitro.Our results identified a series of adaptive genetic changes,ranging from unique convergent substitutional mutations and hitherto undescribed insertions.The region coding for spike proved to be a mutational hotspot,evolving a number of mutational changes including the already known substitutions at positions S:484 and S:501.We discussed the evolution of all specific adaptations as well as possible reasons for the seemingly inhomogeneous potential of SARS-Co V-2 in the adaptation to cell culture.The combination of serial passage in vitro with whole genome sequencing uncovers the immense mutational potential of some SARS-Co V-2 strains.The observed genetic changes of SARS-Co V-2 in vitro could not be explained solely by selectively neutral mutations but possibly resulted from the action of directional selection accumulating favourable genetic changes in the evolving variants,along the path of increasing potency of the strain.Competition among a high number of quasi-species in the SARS-Co V-2 in vitro population gene pool may reinforce directional selection and boost the speed of evolutionary change.展开更多
文摘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.
基金the financial support of the Austrian Research Promotion Agency(FFG),Grant No.35863961。
文摘Since its outbreak in 2019,Severe Acute Respiratory Syndrome Coronavirus 2(SARS-Co V-2)keeps surprising the medical community by evolving diverse immune escape mutations in a rapid and effective manner.To gain deeper insight into mutation frequency and dynamics,we isolated ten ancestral strains of SARS-Co V-2 and performed consecutive serial incubation in ten replications in a suitable and common cell line and subsequently analysed them using RT-q PCR and whole genome sequencing.Along those lines we hoped to gain fundamental insights into the evolutionary capacity of SARS-Co V-2 in vitro.Our results identified a series of adaptive genetic changes,ranging from unique convergent substitutional mutations and hitherto undescribed insertions.The region coding for spike proved to be a mutational hotspot,evolving a number of mutational changes including the already known substitutions at positions S:484 and S:501.We discussed the evolution of all specific adaptations as well as possible reasons for the seemingly inhomogeneous potential of SARS-Co V-2 in the adaptation to cell culture.The combination of serial passage in vitro with whole genome sequencing uncovers the immense mutational potential of some SARS-Co V-2 strains.The observed genetic changes of SARS-Co V-2 in vitro could not be explained solely by selectively neutral mutations but possibly resulted from the action of directional selection accumulating favourable genetic changes in the evolving variants,along the path of increasing potency of the strain.Competition among a high number of quasi-species in the SARS-Co V-2 in vitro population gene pool may reinforce directional selection and boost the speed of evolutionary change.
