Different human coronaviruses (HCoV) caused colds and other diseases in humans long before the COVID-19 pandemic outbreak. Could pre-existing immune responses to closely related circulating human coronaviruses cross-react with SARS-CoV-2? Irene Abela, Chloé Pasin und Magdalena Schwarzmüller investigated this question and aimed to find out if pre-existing HCoV immunity can protect against an infection with SARS-CoV-2 or against severe disease. 

The three awardees developed a novel serology assay to evaluate the diversity of antibody responses to SARS-CoV-2 and HCoV. Utilizing a computational framework, they identified past and current SARS-CoV-2 infections. Based on the evaluation of antibody responses in over 1200 pre-pandemic and pandemic samples they developed a statistical strategy to predict whether an individual has neutralizing plasma antibodies that can prevent an infection with SARS-CoV-2. Furthermore, the scientists investigated whether pre-existing HCoV antibodies influence the development of SARS-CoV-2 antibodies and impact disease severity.

In an interdisciplinary approach, they found that individuals with high pre-existing immunity to HCoV are more likely to develop stronger SARS-CoV-2 specific antibody responses upon SARS-CoV-2 infection. In addition, individuals with high levels of antibodies against HCoV were less likely to require hospitalization. The young scientists demonstrated how prior immunity to circulating HCoV can protect against SARS-CoV-2 acquisition, promote the development of specific antibodies to SARS-CoV-2, and influence disease severity. 

In conclusion, these results suggest that immunity to HCoV may promote the rapid development of SARS-CoV-2-specific immunity, thereby emphasizing the importance of exploring cross-protective responses for comprehensive coronavirus prevention.

Multifactorial seroprofiling dissects the contribution of pre-existing human coronaviruses responses to SARS-CoV-2 immunity. Irene A Abela*, Chloé Pasin*, Magdalena Schwarzmüller*, Selina Epp, Michèle E Sickmann, Merle M Schanz, Peter Rusert, Jacqueline Weber, Stefan Schmutz, Annette Audigé, Liridona Maliqi, Annika Hunziker, Maria C Hesselman, Cyrille R Niklaus, Jochen Gottschalk, Eméry Schindler, Alexander Wepf, Urs Karrer, Aline Wolfensberger, Silvana K Rampini, Patrick M Meyer Sauteur, Christoph Berger, Michael Huber, Jürg Böni, Dominique L Braun, Maddalena Marconato, Markus G Manz, Beat M Frey, Huldrych F Günthard, Roger D Kouyos, Alexandra Trkola. Nat Commun. 2021 Nov 18;12(1):6703
* Contributed equally.