Katarzyna Pieczonka

Ms. Katarzyna Pieczonka


Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2021 in Neurobiology of Disease
Verified
Journal Article
Open access
JCJonathon Chio
Jonathon Chio
JWJian Wang
Jian Wang
VSVithushan Surendran
Vithushan Surendran
LLLijun Li
Lijun Li
MZMohammad-Masoud Zavvarian
Mohammad-Masoud Zavvarian
Michael FehlingsMichael Fehlings
Michael Fehlings
The neuroinflammatory response plays a major role in the secondary injury cascade after traumatic spinal cord injury (SCI). To date, systemic anti-inflammatory medications such as methylprednisolone sodium succinate (MPSS) have shown promise in SCI. However, systemic immunosuppression can have detrimental side effects. Therefore, immunomodulatory approaches including the use of human immunoglobulin G (hIgG) could represent an attractive alternative. While emerging preclinical data suggests that hIgG is neuroprotective after SCI, the optimal time window of administration and the mechanism of action remain incompletely understood. These knowledge gaps were the focus of this research study. Female adult Wistar rats received a clip compression-contusion SCI at the C7/T1 level of the spinal cord. Injured rats were randomized, in a blinded manner, to receive a single intravenous bolus of hIgG (2 g/kg) or control buffer at 15 minutes (min), 1 hour (h) or 4 h post-SCI. At 24 h and 8 weeks post-SCI, molecular, histological and neurobehavioral analyses were undertaken. At all 3 administration time points, hIgG (2 g/kg) resulted in significantly better short-term and long-term outcomes as compared to control buffer. No significant differences were observed when comparing outcomes between the different time points of administration. At 24 h post-injury, hIgG (2 g/kg) administration enhanced the integrity of the blood spinal cord barrier (BSCB) by increasing expression of tight junction proteins and reducing inflammatory enzyme expression. Improvements in BSCB integrity were associated with reduced immune cell infiltration, lower amounts of albumin and Evans Blue in the injured spinal cord and greater expression of anti-inflammatory cytokines. Furthermore, hIgG (2 g/kg) increased expression of neutrophil chemoattractants in the spleen and sera. After hIgG (2 g/kg) treatment, there were more neutrophils in the spleen and fewer neutrophils in the blood. hIgG also co-localized with endothelial cell ligands that mediate neutrophil extravasation into the injured spinal cord. Importantly, short-term effects of delayed hIgG (2 g/kg) administration were associated with enhanced tissue and neuron preservation, as well as neurobehavioral and sensory recovery at 8 weeks post-SCI. hIgG (2 g/kg) shows promise as a therapeutic approach for SCI. The anti-inflammatory effects mediated by hIgG (2 g/kg) in the injured spinal cord might be explained in twofold. First, hIgG might antagonize neutrophil infiltration into the spinal cord by co-localizing with endothelial cell ligands that mediate various steps in neutrophil extravasation. Second, hIgG could traffic neutrophils towards the spleen by increasing expression of neutrophil chemoattractants in the spleen and sera. Overall, we demonstrate that delayed administration of hIgG (2 g/kg) at 1 and 4-h post-injury enhances short-term and long-term benefits after SCI by modulating local and systemic neuroinflammatory cascades.

26 April 2023 in Cells
Verified
Journal Article
Open access
PDF file
KPKatarzyna Pieczonka
Katarzyna Pieczonka
MKMohamad Khazaei
Mohamad Khazaei
Michael FehlingsMichael Fehlings
Michael Fehlings
Oligodendrocytes are the myelinating cells of the central nervous system that facilitate efficient signal transduction. The loss of these cells and the associated myelin sheath can lead to profound functional deficits. Moreover, oligodendrocytes also play key roles in mediating glial-neuronal interactions, which further speaks to their importance in health and disease. Neural progenitor cells (NPCs) are a promising source of cells for the treatment of oligodendrocyte-related neurological diseases due to their ability to differentiate into a variety of cell types, including oligodendrocytes. However, the efficiency of oligodendrocyte differentiation is often low. In this study, we induced the expression of the Olig2 transcription factor in tripotent NPCs using a doxycycline-inducible promoter, such that the extent of oligodendrocyte differentiation could be carefully regulated. We characterized the differentiation profile and the transcriptome of these inducible oligodendrogenic NPCs (ioNPCs) using a combination of qRT-PCR, immunocytochemistry and RNA sequencing with gene ontology (GO) and gene set enrichment analysis (GSEA). Our results show that the ioNPCs differentiated into a significantly greater proportion of oligodendrocytes than the NPCs. The induction of Olig2 expression was also associated with the upregulation of genes involved in oligodendrocyte development and function, as well as the downregulation of genes involved in other cell lineages. The GO and GSEA analyses further corroborated the oligodendrocyte specification of the ioNPCs.

18 November 2025 in Cancers
Verified
Journal Article
Open access
PDF file
ZLZsuzsanna Lichner
Zsuzsanna Lichner
YSYasaman Shamshirgaran
Yasaman Shamshirgaran
KPKatarzyna Pieczonka
Katarzyna Pieczonka
AJAnna Jonebring
Anna Jonebring
MKMark Kibschull
Mark Kibschull
IRIan Rogers
Ian Rogers
Background: Modeling precancerous stages holds the promise to understand early transformation events, thereby offering the potential for personalized, targeted treatment. Because cancer hijacks developmental pathways, precancerous stages could potentially be modeled by reprogramming cancer cells to an induced pluripotent stem cell state and subsequently differentiating them to the target organs using organoid models. Methods: We attempted reprogramming of patient-derived clear cell renal cell carcinoma (ccRCC) cell lines and adjacent normal renal epithelial cell lines using lentivirus or episomal reprogramming vectors. Results: The cancer cells failed to reprogram while the adjacent normal cells reprogrammed with high efficiency. The von Hippel–Lindau factor (VHL) gene was re-expressed in ccRCC cells in an attempt to restore the wild-type phenotype and restore reprogramming. The VHL gene is the major tumor suppressor in ccRCC pathogenesis and a conductor of oxidative-glycolytic glucose metabolism. While its re-expression did restore the epithelial phenotype and oxidative regulation of ccRCC cells, they still failed to stably reprogram. With an optimized reprogramming workflow, VHL-corrected ccRCC cells generate NANOG+ cells; however, they remained dependent on the ectopic expression of the reprogramming factors. Conclusions: We concluded that while VHL expression is necessary for cellular reprogramming of ccRCC cells, other genetic lesions in the ccRCC cells could be preventing the stabilization of the pluripotent state.