Aicha Kriaa’s postdoctoral project is to investigate how gut microbes interact with the large intestine’s protective mucus layer. Credit: Mattias Pettersson, Umeå University
“There is a galaxy of microbes living in the human gut; delving into this microbiome is a true exploration of the unknown,” says microbiologist Aicha Kriaa, a postdoctoral researcher at Umeå University in Sweden. “I find it intriguing that interactions and reactions within the gut microbiome shape our health by modulating our propensity and responses to disease.”
Kriaa is in the initial stages of her postdoc at Umeå, having arrived in the spring of 2023 after completing her degree in her home country of Tunisia and her PhD in Paris, France. She is researching how gut bacteria can degrade the mucosal barrier of the intestines during inflammatory bowel disease (IBD), and is working in the laboratories of Umeå’s Björn Schröder and Ulrika Westerlind.
It’s not just IBD; many diverse health issues, from metabolic diseases to neurological conditions, are related to disruptions within the gut microbiome. Investigating intestinal microbiota has the potential to pinpoint new therapeutic targets and transform treatments for multiple diseases, which is one of Kriaa’s driving motivations.
Kriaa’s postdoc position is part of the ‘Excellence by Choice’ (EC) Programme in Life Sciences at Umeå: a unique approach to postdoctoral study that places the early-career researcher at the heart of research planning, decision-making and implementation.
“This is what drew me to apply to Umeå,” says Kriaa. “I had not come across a postdoc call that centred on ensuring that my own ideas were brought to fruition. The guidance I’m receiving from my supervisors in terms of designing a relevant and pertinent project is invaluable.”
By joining Umeå, Kriaa is following in the footsteps of world-leading researchers, including Emmanuelle Charpentier, who won the Nobel Prize for Chemistry alongside Jennifer Doudna in 2020 for the development of the CRISPR-Cas9 genome editing tool. Much of the groundwork for Charpentier’s pioneering work was conducted at Umeå. Charpentier is honoured to be the patron and a mentor for the EC Programme.
“I hope to encourage young scientists to continue beyond the doctoral stage and pursue a career in fundamental research,” says Charpentier. “At Umeå, I was given the trust and time to focus on projects that I wanted my team to focus on, including CRISPR-Cas9.” She praises the university’s interactive, multidisciplinary research environment: “I was struck by the openness of researchers to discuss their work with junior and senior scientists, and the obvious pride in the success of all colleagues at the university.”
Umeå University cultivates a close-knit community and vibrant atmosphere. From left: professor Yaowen Wu; postdoc Joram Kiriga Waititu; professor Teresa Frisan; postdocs Gabriel Torrens, Samuel Agyei Nyantakyi and Aicha Kriaa; science coordinator Ingrid Söderbergh; professor Fredrik Almqvist; and postdoc Jagadish Mangu. Credit: Mattias Pettersson, Umeå University
Gut health is human health
Kriaa has chosen an ambitious challenge. More than six million people worldwide have IBD. Medications largely treat symptoms rather than offer a cure, and the cause remains obscure. The IBD-gut microbiome link is intricate, and there is no comprehensive understanding of its contribution to IBD — or of the many confounding factors such as diet and lifestyle.
“We have yet to define which bacterial strains are functionally relevant to IBD,” says Kriaa. “Of equal importance will be a molecular understanding of the underlying gut microbial activities. We may not find the culprit, yet we will at least be adding a few more pieces to the whole IBD puzzle.”
The main aim of Kriaa’s research project is to unlock the microbial-host interactions in the protective mucus layer that lines the large intestine. Scientists know that the integrity of this mucosal layer is compromised during the early stages of IBD, particularly in ulcerative colitis. Kriaa believes that this degradation may be underpinned by skewed bacterial activity, with certain microbes releasing excessive levels of enzymes and metabolites that destroy the mucus.
“Once this intestinal barrier is broken, harmful bacteria can penetrate, further fuelling IBD,” says Kriaa. “We now have game-changing tools to examine the intricate interactions at the mucus interface, and I am excited to have access to these technologies at Umeå.”
Emmanuelle Charpentier during her time at Umeå University, where she was given time and support to work on fundamental research, including into CRISPR-Cas9.Credit: Hallbauer und Fioretti
Excellence by Choice
The EC Programme was launched in 2015 by Umeå University to mark its 50th anniversary. It was established by Bernt Eric Uhlin, founding director of The Laboratory for Molecular Infection Medicine Sweden, based in Umeå’s Centre of Microbial Research (UCMR). Today, the new EC Programme is a collaboration between two national Centres of Excellence at Umeå University: UCMR and the Umeå Plant Science Centre (UPSC).
Scientists at both centres are involved in diverse, pioneering research, from examining how plants adapt to environmental challenges, to determining host–pathogen interactions and contributing to international efforts to mitigate the COVID-19 pandemic. The EC Programme is funded by the Knut and Alice Wallenberg Foundation and the Kempe Foundations, who support long-term research into basic biology, medicine and advancing technologies that will benefit both Sweden and the wider world.
“We hope to attract excellent young scientists to Umeå, with the goal of providing top class training for the next generation,” says biochemist Yaowen Wu, director of UCMR. “Our close-knit community creates a vibrant atmosphere conducive to building new collaborations across the life sciences.”
For the EC Programme, the university will recruit 15 postdocs on fellowships, with the first 8 already accepted. The next call opens at the end of September 2023. Each postdoc is expected to create and lead a collaborative project under the supervision of at least two principal investigators, notes Wu. Postdocs from all over the world are welcome to apply, and the university is particularly keen to encourage applications from women.
“Successful research is closely linked to diversity,” says Charpentier. “Integrating people from different backgrounds and cultures fosters an environment and atmosphere conducive to opening up new types of discussions, interactions and avenues in research. Umeå actively achieves this.”
In addition to full funding for their project, each postdoc gets a grant for their career development. EC postdocs are actively engaged in the local postdoctoral community, with access to the Umeå Postdoc Society, together with networking opportunities, workshops and seminars run by the programme.
And the city itself has much to offer. “Umeå is in a truly beautiful location, with direct access to multiple outdoor pursuits in all seasons,” says Wu. “It is a safe, compact, and very international city.”
“I’m touched by the way I’ve been welcomed to Umeå,” says Kriaa. “There is a cosy, friendly atmosphere to both the university and the city as a whole; it is a peaceful place to be.”
Charpentier adds a closing note of encouragement for young scientists to apply. “You will experience research in a highly interactive and exciting environment, where every effort is made to support you.”