There are many good reasons to go to Greifswald for a short-term senior research fellowship at Alfried Krupp Wissenschaftskolleg (Figure 1). But most important for me was the research environment at Universität Greifswald and especially the research groups from Professor Barbara Bröker and Professor Uwe Völker. Their excellent interdisciplinary research environment in infection biology, and with a focus on Staphylococcus aureus, gave me the opportunity for scientific exchange and interdisciplinary cooperation. Throughout my research stay I was generously invited to join and learn from the research environment in infection biology at Department of Immunology, Universitätsmedizin Greifswald, and to share my experiences as a research colleague, supervisor, mentor, and leader in academia.

Staphylococcus aureus is a notorious opportunistic human pathogen able to enjoy a wide variety of lifestyles. Either commensal, peacefully colonising different niches of the human body, or pathogenic, invading host tissues by using its arsenal of virulence determinants (recently and thoroughly reviewed by Raineri, 2022). S. aureus is the second most common species isolated from blood cultures in Norway (NORM/NORM-VET 2022) exemplifying its importance as contributor to the overall morbidity and mortality in society. There is no effective vaccine available and treatment failure due to antimicrobial resistance (AMR), intracellular persistence, or biofilm formation occurs frequently. A recent report about the global burden of AMR claimed that in 2019 methicillin resistant S. aureus (MRSA) alone caused more than 100.000 deaths in the world (Antimicrobial Resistance Collaborators, 2022). Thus, a broader knowledge about how S. aureus and its human host interacts with and responds to each other might reveal useful targets for future infection prevention and/or treatment.

 Interesting novel targets to control S. aureus colonisation, infection prevention and treatment, might be found among body-niche-specific interactions between bacteria and humans. Using proteomics to study S. aureus responses to human cells derived from relevant body niches is one approach to find such targets for follow-up studies. The WIKO fellowship enabled me to establish contact with the Department of Functional Genomics (Head of Department Professor Uwe Völker). Their expert input from bioinformatics and proteomics facilitated data interpretations and enhanced the quality of the analyses in progress. Our discussions also led to follow-up studies by a collaborative project now in progress.

The Study of Health in Pomerania (SHIP) at Uni- Greifswald and The Tromsø Study (TU), hosted by UiT (https://uit.no/research/tromsostudy), are both population-based studies that have generated important knowledge about immunological responses to S. aureus nasal carriage, and risk of developing allergic diseases (f.ex. Meyer, 2021; Sørensen, 2017). These studies have also added important information about risk factors contributing to S. aureus colonisation of the human host e.g., age, gender, BMI, contraceptives use and social network (Sangvik, 2011; Olsen, 2013; Stensen, 2019 & 2022). My stay at Uni-Greifswald gave me the opportunity to learn more about the SHIP study and discuss possibilities for future collaborative studies in our respective cohorts.

To be granted the short-term fellowship for scientific exchange, interdisciplinary and international co-operation at the Alfried Krupp Wissenschaftskolleg and to be part of the academic life in Greifswald was a tremendous experience. In addition to my Fellow’s lecture, I was invited to give a research presentation at the “Late lunch seminar” series at Universitätsmedizin Greifswald and to participate at the RTG-PRO “Proteases in pathogen and host: importance in inflammation and infection” retreat May 10-12, 2023.

Social activities are important ingredients to a fruitful research stay, and for me fellow lunches, the WIKO excursion to Rügen and the farewell-party on the roof were immensely enjoyable. I was also fortunate to have equally nice social interactions with the research group at UniMed. Today, back in Tromsø (Figure 2-3), I am tremendously grateful to WIKO and WIKO staff for granting the fellowship and facilitating the stay in Greifswald. I would also like to express my gratitude to Professor Barbara Bröker and the Department of Immunology, Universitätsmedizin Greifswald, for hosting me.

References

• Antimicrobial Resistance Collaborators. Global burden of bacterial antimicrobial resistance in 2019: a systematic analysis. The Lancet (2022) https://doi.org/10.1016/S0140-6736(21)02724-0
• Meyer TC, Michalik S, Holtfreter S, Weiss S, Friedrich N, Völzke H, Kocher T, Kohler C, Schmidt F,
• NORM/NORM-VET 2022. NORM/NORM-VET 2022. Usage of Antimicrobial Agents and Occurrence of Antimicrobial Resistance in Norway. Tromsø / Oslo 2023. ISSN:1502-2307 (print) / 1890-9965 (electronic).
• Olsen K, Danielsen K, Wilsgaard T, Sangvik M, Sollid JUE, Thune I, Eggen AE, Simonsen GS, Furberg AS (2013). Obesity and Staphylococcus aureus Nasal Colonization among Women and Men in a General Population. PLOS One 8:e63716
• Raineri EJM, Altulea D, van Dijl JM.  Staphylococcal trafficking and infection—from ‘nose to gut’ and back. FEMS Microbiology Reviews (2022) 46:1–22. https://doi.org/10.1093/femsre/fuab041
• Sangvik, M., Olsen, R.S., Olsen, K., Simonsen, G.S., Furberg, A.S., and Sollid, J.U. 2011. J. Clin. Microbiol. 49, 4213-4218.
• Stensen D, Småbrekke L, Olsen K, Nielsen CS, Simonsen GS, Sollid JUE, Furberg AS (2019). Hormonal contraceptive use and Staphylococcus aureus nasal and throat carriage in a Norwegian youth population. PLoS ONE 07/2019; 14(7):e0218511
• Stensen DB, Nozal Cañadas RA, Småbrekke L, Olsen K, Nielsen CS, Svendsen K, Hanssen AM, Ericson JU, Simonsen GS, Bongo LA, Furberg AS. (2022). Social network analysis of Staphylococcus aureus carriage in a general youth population. International Journal of Infectious Diseases 123:200-209. doi.org/10.1016/j.ijid.2022.08.018
• Sørensen M, Klingenberg C, Wickman M, Sollid JUE, Furberg AS, Bachert C, Bousquet J. (2017) Staphylococcus aureus enterotoxin sensitization is associated with allergic poly‐sensitization and allergic multimorbidity in adolescents. Allergy 72 (10), 1548-1555