Areas of research

Influence of cell-cell interaction on the migration activity of cancer cells

The animal cells' capability of active migration has been observed during such processes as: embryonic development, immunological reactions and wound-healing processes. Gaining the ability to migrate in a manner uncontrolled by the organism is also one of the most important properties that enable malignant neoplasms to infiltrate neighbouring tissues and metastasize to distant areas of the body, which is responsible for cancer patients' deaths more often than the uncontrolled growth itself.

Much research has suggested a correlation between cancer cell mobility and the risk of metastasis. The migration of cancer cells during the process of metastasis is by no means a random process. Its direction and the movement of cancer cells are influenced by a number of external factors caused by the normal cells of the organism in which a neoplasm develops, or by the cancer cells themselves. The best known types of directional reaction of cells are chemotaxis, haptotaxis, electrotaxis and contact guidance. Another, separate group of factors that influence cancer cell migration during metastasis are direct cell-cell interactions. The majority of invasive cells are characterized by the lack or limitation of contact inhibition of migration and can, to a greater or lesser extent, migrate on the surface of other cells (both normal and cancer). Direct contact with other cells can increase the movement activity of cancer cells and their capability of efficient migration. One of the areas of research conducted at the Department is the study of contact stimulation mechanisms of cancer cell migration (more information about the subject is available under this link).

Role of thioredoxin reductase in regulating cell movement activity

Besides their damaging effect on cell structures, reactive oxygen species (ROS) are an important factor in transmitting signals in the cell. Their role in these processes mainly consists in regulating the activity of enzymatic proteins, especially phosphatases and kinases, by reversible oxidation. The modification of protein activity caused by oxidation also requires a reverse mechanism, which makes the regulated proteins return to their initial state. One of the postulated enzymatic systems responsible for this process is the thioredoxin system. Thioredixin is a small peptide, whose molecular mass is 12 Kda. Thioredoxins can reduce disulphide bridges of proteins in a process which involves their own oxidation. Reactivation of thioredoxin is caused by the activity of thioredoxin reductase. Besides protecting proteins from oxidative stress, thioredoxin system is also involved in a number of functions related to redox regulation of many of the proteins crucial for the signal transmition in the protein cells, for instance: ASK 1 kinase, tyrosine phosphatase PTP1B, serine-threonine phosphatase PP2B, or protein kinase C. The Department also conducts research into the role of thioredoxin reductase in the processes of cell movement activity, the structure of actin cytoskeleton, and the intercellular communication through gap junctions (more information about the subject is available under this link).

Intercellular communication in cancer etiopathogenesis

The elements of surface complex, which consists of extracellular matrix receptors and intercellular adhesion receptors, together with the system of proteins interacting with the cytoskeleton determine the mechanic integrity of many tissues. They were also identified as one of the factors responsible for cell transformation and the development of cancer. Yet, the role of direct metabolites' transfer through gap junctions (connexons) still remains uncertain. At the early stages of carcinogenesis, the lack or attenuation of intercellular metabolite transfer between the neoplastic cells may weaken the effectiveness of tissue systems regulating cell growth and thus promote neoplastic transformation. On the other hand, it has been indicated that some types of cells with high metastatic potential are characterized by high level of intercellular metabolite transfer through gap junctions. The research at the Department concentrates on the functions of the surface complex, consisting of cell-extracellular matrix adhesion receptors (e.g. integrins), intercellular adhesion receptors (e.g. cadherins), and gap junctions (built of connexins), during the cancer progression process and its potential role in cancer cell metastasis (more information is available under this link).

Tissue engineering – medical biotechnology – stem cells

Tissue engineering is an alternative to the conventional methods of treating tissue losses due to an injury or cancer. It is based on the use of human cell cultures grown outside the body on a scaffold imitating extracellular matrix typical for a given tissue. This field of biotechnology has been developing for more than 20 years, thanks to advances in the methods of isolation and culture of cell populations enriched with stem cells responsible for tissue regeneration.

Optimizing the isolation and culture of these cells while maintaining their undifferentiated phenotype and high proliferation activity has been a goal of laboratories all over the world. This involves studies into these cells' biology, which can enable researchers to control the processes of their differentiation and aging.

The clinical use of in vitro cultured keratinocytes has become widespread in the cases, when natural regeneration mechanisms fail. Transplantation of in vitro cultured keranocytes is primarily applied in burns and chronic wounds treatment. They ensure fast and durable protection of a wound, and good cosmetic effect, thanks to the reduction of wound shrinking process and the lack of scar tissue formation.

The pace and the quality of the regenerating epidermis depends on the number of stem cells among the cells transplanted to a given patient, as only these cells can ensure permanent epidermal tissue regeneration. The creation of cultures enriched with stem cells can significantly improve the grafts' effectiveness. The Laboratory of Cell and Tissue Engineering specializes in autologous human skin cells culture and their clinical application in burns and chronic wounds treatment (more information under this link)

On October 7, 2011 Dr Justyna Drukała gave an interview for the Polish TV programme Kawa czy Herbata. The leading topic was skin cell culture at the Laboratory of Cell and Tissue Engineering. Parts of the interview can be watched on the Polish Television website: http://www.tvp.pl/styl-zycia/magazyny-sniadaniowe/kawa-czy-herbata/wideo/hodowle-komorek-skory/5420437

Research on the mechanisms of phenotypical fibroblast to myofibroblast transition in bronchial asthma

Bronchial asthma is one of the most common respiratory tract diseases nowadays, as it affects about 10 percent of human population. The respiratory tract inflammation is accompanied by bronchial epithelium damage and repair processes, which cause structural and functional changes called airway remodeling.

Despite intense studies, it still remains unknown if the airway remodeling is just a result of a chronic inflammation of mucous membrane, or one of the causes of the illness. The typical features of persons suffering from asthma include the sub-basement membrane thickening and the emergence of a large number of myofibroblasts (cells whose phenotype is something in-between fibroblasts and smooth muscle cells) in the adjoining reticular layer, which leads to the thickening of bronchial wall.  According to the hypothesis of Holgate at al., endothelial cells and fibroblasts of bronchial mucous membrane form the functional epithelial-mesenchymal trophic unit. According to this hypothesis, the endothelium damage leads to the increased release of mediators, which, in turn, activate the fibroblast to myofibroblast transition and increase their expression and the release of extracellular matrix proteins.

The Department conducts in-vitro research based on the application of bronchial fibroblasts obtained through bronchial biopsies from persons suffering from asthma and persons who have been diagnosed as not having any upper respiratory tract disease. The studies concentrate on the mechanisms of phenotypic fibroblast to myofibroblast transition and the search for the factors that facilitate the changes in under-endothelial bronchial wall of asthmatics. Understanding how the airway remodeling works can make it possible to reverse or stop the process with new medicines used in asthma therapy or prevention.

Optimization of selected stem cell populations' applications in experimental cardiology

Stem cells (SC) have recently become an interesting subject for dozens of studies conducted around the world, providing considerable opportunities for their application in regenerative medicine, including experimental cardiology.
The research conducted in the Department of Cell Biology is also focused on this subject and includes optimization of isolation and culture procedures for multiple SC and progenitors, in order to apply them in regeneration of tissues damaged during ischemia. SC used in our studies are harvested from several vast biological sources, including bone marrow (BM), umbilical cord blood (UCB) and Wharton jelly and adult tissues such as heart muscle. All the mentioned sources are utilized in our Department for isolating animal and human mesenchymal stem cells (MSCs), endothelial progenitor cells (EPCs), very small embryonic-like stem cells (VSELs) and endogenous heart progenitors – cardiac SC (CSCs). Additionally to the above mentioned SC populations isolated from natural tissues reservoirs, in our laboratory we have also optimized, thanks to genetic reprogramming the procedures for obtaining murine and human clones of induced pluripotent stem cells (iPS).
Our ongoing studies conducted in collaboration with the US partners ((Institute of Molecular Cardiology, University of Louisville and Cardiovascular Research Institute, University of Kansas) have indicated that an adherent fraction of BM- derived, non-hematopoietic (CD45neg) MSCs that expresses some selected SC and mesenchymal antigens (e.g. Dca-1, CD90), but do not  express CD105 markers (CD105neg) exhibits greater angiogenic and cardiomyogenic differentiation potential  when compared to the whole fraction of MSCs.
The recently conducted research focuses on isolation of MSCs fractions predestinated to angiogenic and cardimyogenic differentiation that may be more effective following their injection into heart tissue.  
In our Department, we also investigate the potential applications of various pluripotent SC fractions, including those harvested from adult tissues (VSELs) and created by genetic induction (iPS), for multiple purposes of experimental cardiology (http://www.stemcells-project.eu/). We also study the potential role of paracrine effects – including microvesicles (MVs) shed by SC and progenitor cells – in tissue regeneration. This study is conducted within TEAM project founded by FNP.

Optimization of methods for identifying and isolating stem and progenitor cell populations for applications in regenerative medicine

Optimization of methods for identification and isolation of SC and progenitor cells is an important aspect of the preparation of these cells for their further use in preclinical and clinical applications in regenerative medicine.
Because of this valid reason, we conduct research focused on identification of SC with distinct functional characteristics based on their specific antigenic profile. The identification is carried out not only by employing classical and imaging cytometry (ImageStream), but also on the genetic and proteomic level (mRNA, microRNA, proteins). We utilize both immunomagnetic cell sorting (MACS) and Fluorescence-Activated Cell Sorting (FACS) for isolation of SC and progenitor cells from various tissues.
In our Department we also focus on optimizing isolation and expansion protocols for BM- and UCB- derived SC (MSCs, VSELs), subpopulations of tissue- specific progenitors (EPCs, CSCs) as well as iPS cells.
In collaboration with the Stem Cell Institute, University of Louisville, and Cardiovascular Research Institute, University of Kansas in the USA, we have established novel protocols for isolation of VSELs and MSCs by employing multiparameter classical and imaging cytometry (US PA No: 20100267107 oraz 20090155225; link:
http://www.faqs.org/patents/app/20100267107; http://www.faqs.org/patents/app/20090155225).