Elżbieta Pajtasz-Piasecka

Publications of Elżbieta Pajtasz-Piasecka

• Generation of antitumor response by IL-2-transduced JAWS II dendritic cells.

  Authors: Joanna Rossowska, Elżbieta Pajtasz-Piasecka, Oliwia Ryśnik, Justyna Wojas, Agnieszka Krawczenko, Anna Szyda, Danuta Duś

  Immunobiology. 05/2011; 216(10):1074-84.

  Antigen-loaded dendritic cells (DCs) are a promising tool for inducing a tumor-specific immune response. It seems probable that co-administration of those cells together with cytokine-transduced DCsAntigen-loaded dendritic cells (DCs) are a promising tool for inducing a tumor-specific immune response. It seems probable that co-administration of those cells together with cytokine-transduced DCs can further increase effectiveness of the antitumor vaccine. The local production of IL-2 by genetically modified DCs may result in alteration of the unfavorable tumor environment causing immune response dysfunction. In the presented study murine DCs of an established JAWS II cell line were transduced with a retroviral vector carrying murine IL-2 gene (JAWS II/IL-2). JAWS II/IL-2 cells demonstrated slightly decreased tumor antigen (TAg) uptake capacities. However, this modification resulted in enhanced ability of the cells to migrate in vivo. The multiple injection of vaccines containing JAWS II/IL-2 cells caused MC38 tumor growth delay and prolonged mice survival. The immunological response was manifested as cytotoxic natural killer (NK) and T cell activation and tumor tissue infiltration by CD8(+) and CD4(+) cells, accompanied by increased IFN-γ production by spleen cells. These observations suggest that repeated peritumoral administration of IL-2-producing dendritic cells can inhibit tumor growth by intensification of CD8(+) and CD4(+) cells' influx into tumor tissue and further activation of the systemic antitumor response. It can be concluded that IL-2 transduced dendritic cells may be used as a potent adjuvant in antitumor immunotherapy.

• [The influence of transcription factors on CD4+ T cell differentiation].

  Authors: Kalina Świst, Elżbieta Pajtasz-Piasecka

  Postȩpy higieny i medycyny doświadczalnej (Online). 01/2011; 65:414-26.

  A number of distinguished populations with manifold functions and various pathways of differentiation have been identified within T lymphocytes. The cells expressing CD4 coreceptor on their cellA number of distinguished populations with manifold functions and various pathways of differentiation have been identified within T lymphocytes. The cells expressing CD4 coreceptor on their cell surface are the most varied group. Depending on changes in different tissue microenvironments induced by such cytokines as IL-4, IFN-γ, IL-10 or TGF-β, CD4+ T lymphocytes can differentiate into alternative subpopulations performing helper, regulatory/suppressor function (Th1, Th2, Th9, Th17, Th22, Tfh, iTreg and Tr1). In the direction of lineage differentiation of these lymphocytes, transcription factors play the key role. The most important of them are T-bet, GATA3, RORγt, FOXP3, AHR and c-Maf. A cytokine binding to a specific receptor activates the transcription factors, other DNA-binding proteins, and epigenetic alterations, enabling the transcription of proper genetic information. The plasticity of CD4+ cell differentiation seems to be in dynamic balance between initial commitment and flexibility of these cells in the face of a changing environment. Even more, phenotypical and functional borders between particular subpopulations have turned out to be fluent. Then, the influence of extrinsic factors on the activation of mechanisms responsible for conversion of CD4+ T lymphocytes into functional mature cells appears to be more complicated than was previously thought.

• Bacteriophages support anti-tumor response initiated by DC-based vaccine against murine transplantable colon carcinoma

  Authors: Elżbieta Pajtasz-Piasecka, Joanna Rossowska, Danuta Duś, Beata Weber-Dąbrowska, Agnieszka Zabłocka, Andrzej Górski

  Immunology Letters.

  Bacteriophages in eukaryotic hosts may behave as particulate antigens able to activate the innate immune system and generate adaptive immunity. Dendritic cells (DCs) play a key role in the initiationBacteriophages in eukaryotic hosts may behave as particulate antigens able to activate the innate immune system and generate adaptive immunity. Dendritic cells (DCs) play a key role in the initiation of the immune response, mainly by priming T cell-mediated immunity. For this reason, they are increasingly applied as an adjuvant for effective anti-tumor therapies in animal models as well as in a few clinical trials. The presented study focused on the application of mouse DCs which were activated with T4 bacteriophages (T4 phages, T4) and further loaded with tumor antigens (TAg) in inducing an anti-tumor response. The activation of bone marrow-derived DCs with T4 phages and TAg resulted in augmentation of their differentiation marker expression accompanied by an enhanced ability to prime T cells for IFN-γ production. These activated DCs (BM-DC/T4 + TAg) were used in experimental immunotherapy of C57BL/6 mice bearing advanced MC38 colon carcinoma tumors. As a result of their triple application, a significant tumor growth delay, up to 19 days, was observed compared with the controls – treated with BM-DCs activated only with T4 phages, TAg, or lipopolysaccharide solution [“solvent”], where the tumor growth delay did not exceed 7 days. The percentage of tumor growth inhibition estimated 10 days after the third cell injection ranged from 32% (for animals treated with BM-DC/TAg cells) to 76% (for animals treated with BM-DC/T4 + TAg cells) over the tumor-bearing untreated control mice.The obtained data indicate that in vitro interactions between T4 phages and BM-DCs followed by TAg activation caused augmentation of the anti-tumor effect when DCs were used as a vaccine for tumor-bearing mice treatment. Therefore, pretreatment of DCs with the phages may be considered as a beneficial element of a novel strategy in anti-tumor immunotherapy.