Pekka Katajisto, Principal Investigator

I am fascinated by the biology of aging. How and why our stem cells eventually fail to maintain tissue functions and physiological integrity? To me, that simply is the most interesting question - one that also continually spurs new research directions for the lab. /

Agustin Sola Carvajal, Lab Manager, KI

Stress is one of the most influencing factors in aging. Removing stress from our PhD students and postdocs and helping them to have a healthy research is my main focus. I am also interested on understanding how the stem cells of the skin behave during aging and development.

Jenny Bärlund and Maija Simula, Lab Managers, UH

Our main interest is to research and prevent the premature aging of our colleagues by focusing on lab management and taking care of running issues in the Helsinki lab. At present, the relative grayness of the test population is minor. /

Emilia Kuuluvainen, Research Coordinator

I'm interested in how changes in a cell's environment or metabolism affects chromatin and transcription activity to control cell identity. I coordinate research collaboration on projects related to stem cell metabolism within MetaStem and Katajistolab. My tasks also include science communication, organizing seminars and keeping things running.

Iiro Hämäläinen, Project Coordinator

I work as an administrative coordinator and take care of financial, HR and general matters of the lab. My interest is to help researchers focus on what they do best - top science.


Ana Amaral

Mitochondria are my favourite organelle in the cell since, in addition to being responsible for energy production, they also regulate many cellular processes via signalling mechanisms. At the Katajisto lab, I am involved in projects aimed at understanding how mitochondria and metabolic phenotype determine the fate of adult stem cells after asymmetric divisions. I also love bringing people together and organising social lab activities.

Ashish Kumar

A subtle variation in cellular milieu can make a remarkable difference at the interface of metabolism and vice-versa. Hence, it always intrigued me how selection of different metabolites by cells govern their varied fate such as adaptation, survival, differentiation and cell death. I am interested to explore this metabolic nexus and the interplay between stem cells and its niche in intestine.

Johanna Englund

Tissue microenvironment determines multiple aspects of cell behaviour. I am interested in exploring how extracellular matrix affects stem cell maintenance and lineage specification during tissue remodelling and cancer initiation in the mammary gland.

Kati Ahlqvist

Mitochondria are the main producers of ATP in the cells but they have many other essential functions besides that. The role of mitochondria in stem cell homeostasis and function is only starting to unravel and I’m interested in studying how mitochondrial biogenesis and mitochondrial DNA maintenance are regulated in stem cells, especially in the hematopoietic system.

Sandra Scharaw

Stem cells maintain tissue function by balancing self-renewal and differentiation, which is controlled by signaling cues from their surrounding niche. My research focuses on the cellular secretion processes that ensure successful signal delivery from the niche Paneth cells to the stem cells in the small intestine. I try to understand how the signal secretion is regulated and adapted in order to determine the stem cell fate.

Swetha Gopalakrishnan

I am a developmental biologist turned stem cell biologist. Using skeletal muscle stem cells (satellite cells), I aim to study stem cell dynamics during activation and injury response. Importantly how changes in cellular metabolism influence cell fate decisions in these cells.

Rodrigo Lozano

My interests are focused on tissue engineering. At the Katajisto lab, my main interest is investigating the role of mechanical forces, niche contour, and extra cellular matrix (ECM) constituents, to understand the role they play in maintaining crypt function and intestinal tissue renewal.


Anna Webb

My main interest is the interplay between intestinal cell types and their microenvironment, in homeostatic conditions as well as in early stages of colorectal cancer. Part of the microenvironment is the extracellular matrix, which provides structural support as well as factors to the intestinal epithelial cells. I am also investigating at what extent the extracellular matrix affects the intestinal epithelial cells.

Daniel Borshagovski

I am interested in how cell-intrinsic changes in aging tissues influence the interactions between stem cells and their niches and how these changes contribute to the deterioration of tissue function in aging animals. I aim to study the molecular features of single cells, with techniques such as single-cell RNA sequencing, to understand the importance of the niche for stem cell function in homeostasis and pathological states

Hien Bui

During asymmetric division, some stem cells asymmetrically organize and divide organelles. I am interested in understanding how this occurs and influences cell fate. In the lab, I am focusing on studying the mechanism that regulate age-selective segregation of peroxisomes during stem cell division.

Julia Döhla

Stem cell exhaustion is a key contributor to age related tissue demise. My interest is focused on the mechanisms stem cells use to avoid accumulation of damage and to maintain tissue renewal. Understanding how stem cells recognize and rid themselves of damaged cellular material in order to preserve their functionality can give important clues about aging and longevity.

Nalle Pentinmikko

My interests are focused on stem cell niches. Organized interplay between the niche and stem cells maintain tissue homeostasis during the lifetime and is a vital part of longevity. Although tissue maintenance is finely tuned it’s not perfect and errors in the system are usually disastrous from the organisms point of view. Thus, knowledge from the basic biology of stem cell niches can point out valuable intervention targets in aging related diseases.

Sharif Iqbal

Extracellular matrix (ECM) is an integral part of the stem cell niche. As part of the niche, ECM facilitates stroma-epithelium cross-talk, provides contextual information and impacts stem cell fate decisions. I am interested in investigating the molecular mechanisms of how ECM contributes to stem cell functions during homeostasis, regeneration and ageing especially in the mouse small intestine.

Simon Andersson

Intestinal stem cells face the most metabolically varying conditions in the body. My interests lie in how stem cells and their niche cooperate to navigate such rapidly changing metabolic environments, I am particularly interested the role mitochondria play in stem cell function.


Eliisa Vähäkangas

My interests lie in asymmetric cell division. I am fascinated to find out more about the cellular reach of asymmetric division, as in what all components in cells can be apportioned asymmetrically during stem cell division. In the lab I am working with Hien in looking at the asymmetrical apportioning of peroxisomes.

Ernesta Nestaite

Stem cells have an ever so growing potential which interests me how do they interact during regeneration, what determines their fate, what can be done to extend their longevity, and most importantly, how can all this knowledge be incorporated into therapeutics. Exploring regeneration and pathways involved in it affected by age is my current interest.

Martin Sandvik

I'm especially keen on studying satellite cells, that is, skeletal muscle stem cells, and how the interplay between these and the immune system enables the regeneration of skeletal muscles after an injury. During aging, both systemic and cell-intrinsic changes contribute to dysfunctions in the regeneration of skeletal muscles, and by understanding the basic mechanisms involved, we could combat some of the muscle degenerative diseases.

Ville Lehtonen

I'm a bioinformatician interested in better understanding the biology of aging and the role of stem cells in the aging process. Currently, I'm studying muscle stem cell activation and differentiation by using single cell RNA-seq data. My research focuses on understanding the regulatory mechanisms of this process and on the distinct metabolic pathways that cells adopt as they progress through the differentiation trajectory.


Kalle Luopajärvi - Bachelor's student -2020
Matthias Schewe - PostDoc -2020
Martin Broberg - Bioinformatician -2020
Hanne Cojoc - Master of Science (Technology) 2020
Tomas McKenna - PostDoc -2019
Linda Olkkonen - Master of Science (Technology) 2017
Ella Salminen - Master's student -2017
Jigishu Ahmed - Master of Science 2017
Eino Markelin - Master's student -2017
Emmi Tiilikainen - Technician -2016
Emir Sadi Cansu - Master of Science 2015
Cristina Martos Rus - Master of Science 2015
Alberto Quattrocchi - Master of Science 2014