Radiation-induced DNA damage and repair in human γδ and αβ T-lymphocytes analysed by the alkaline comet assay

It has been shown by a number of authors that the radiosensitivity of peripheral blood mononuclear cells (PBMC) is higher in cancer patients compared to healthy donors, which is interpreted as a sign of genomic instability. PBMC are composed of different cell subpopulations which are differently radiosensitive and the difference between cancer patients and healthy donors could also be due to different composition of their PBMC pools. Gamma-delta T-lymphocytes play an important role in immunosurveillance and are promising cells for immunotherapy. Their abundance is frequently reduced in cancer patients so should their sensitivity to radiation be lower than that of other T-lymphocytes, this could, at least partly explain the low radiosensitivity of PBMC from healthy individuals compared to cancer patients. The present investigation was carried out to test this. Using the alkaline comet assay we analysed the level of DNA damage and repair in isolated γδ T-lymphocytes, pan T-lymphocytes and in total PBMC exposed in vitro to gamma radiation. We found no difference in the level of DNA damage and the capacity of DNA repair between the T cell populations. This is the first study that addresses the question of sensitivity to radiation of gamma-delta T-cells

Elements of radiobiology for pilot Pirx

Contrary to the widespread opinion, interstellar space is not empty but filled with high energy particles that originate from within and from outside of our Solar system. these particles can induce ionization lesions in human cells and present a health hazard for astronauts. dna is the most sensitive component of the cell and induction of dna damage by ionizing radiation triggers a cascade of signals which can either push the cell towards committing suicide by apoptosis or initiate repair processes. a number of repair pathways exist but none of them is error-free. repair mistakes can lead to the formation of mutations which are potential sources of cancer. the actual doses received by the astronauts in space is a matter of debate. a number of studies have been performed to assess the dose by means of biological dosimetry. this method relies on the analysis of chromosomal aberrations in peripheral blood lymphocytes. most studies show an increased frequency of aberrations in lymphocytes of astronauts who spent at least several weeks in space. this clearly shows that space travel is associated with a risk of developing cancer

Figure 4 in Body cavity cells of Parachela during their active life

Figure 4. Histochemical staining of Hypsibius dujardini, Macrobiotus polonicus, Xerobiotus pseudohufelandi, and Isohypsibius granulifer granulifer; arrows indicate a positive reaction. A–C, histochemical staining of the storage cells of I. g. granulifer. LM. A, Periodic Acid-Schiff (PAS) method, scale bar = 7 µm. B, Sudan black B staining, scale bar = 5 µm. C, bromophenol blue staining (BPB), scale bar = 6 µm. D–F, histochemical staining of the storage cells of H. dujardini. LM. D, PAS method, scale bar = 6 µm; E, Sudan black B staining, scale bar = 6 µm; F, BPB, scale bar = 6 µm. G–I, histochemical staining of the storage cells of M. polonicus. LM. G, PAS method, scale bar = 9 µm; H, Sudan black B staining, scale bar = 7 µm; I, BPB, scale bar = 8 µm. J–L, histochemical staining of the storage cells of X. pseudohufelandi. LM. J, PAS method, scale bar = 11 µm; K, Sudan black B staining, scale bar = 11 µm; L, BPB, scale bar = 11 µm. LM, light microscope.Published as part of <i>Hyra, Marta, Rost-Roszkowska, Magdalena M., Student, Sebastian, Włodarczyk, Agnieszka, Deperas, Marcin, Janelt, Kamil & Poprawa, Izabela, 2016, Body cavity cells of Parachela during their active life, pp. 878-887 in Zoological Journal of the Linnean Society 178 (4)</i> on page 885, DOI: 10.1111/zoj.12463, <a href="http://zenodo.org/record/10110454">http://zenodo.org/record/10110454</a&gt

Identification and characterization of stromal-like cells with CD207+/low CD1a+/low phenotype derived from histiocytic lesions – a perspective in vitro model for drug testing

Abstract Background Histiocytoses are rare disorders manifested by increased proliferation of pathogenic myeloid cells sharing histological features with macrophages or dendritic cells and accumulating in various organs, i.a., bone and skin. Pre-clinical in vitro models that could be used to determine molecular pathways of the disease are limited, hence research on histiocytoses is challenging. The current study compares cytophysiological features of progenitor, stromal-like cells derived from histiocytic lesions (sl-pHCs) of three pediatric patients with different histiocytoses types and outcomes. The characterized cells may find potential applications in drug testing. Methods Molecular phenotype of the cells, i.e. expression of CD1a and CD207 (langerin), was determined using flow cytometry. Cytogenetic analysis included GTG-banded metaphases and microarray (aCGH) evaluation. Furthermore, the morphology and ultrastructure of cells were evaluated using a confocal and scanning electron microscope. The microphotographs from the confocal imaging were used to reconstruct the mitochondrial network and its morphology. Basic cytophysiological parameters, such as viability, mitochondrial activity, and proliferation, were analyzed using multiple cellular assays, including Annexin V/7-AAD staining, mitopotential analysis, BrdU test, clonogenicity analysis, and distribution of cells within the cell cycle. Biomarkers potentially associated with histiocytoses progression were determined using RT-qPCR at mRNA, miRNA and lncRNA levels. Intracellular accumulation of histiocytosis-specific proteins was detected with Western blot. Cytotoxicyty and IC50 of vemurafenib and trametinib were determined with MTS assay. Results Obtained cellular models, i.e. RAB-1, HAN-1, and CHR-1, are heterogenic in terms of molecular phenotype and morphology. The cells express CD1a/CD207 markers characteristic for dendritic cells, but also show intracellular accumulation of markers characteristic for cells of mesenchymal origin, i.e. vimentin (VIM) and osteopontin (OPN). In subsequent cultures, cells remain viable and metabolically active, and the mitochondrial network is well developed, with some distinctive morphotypes noted in each cell line. Cell-specific transcriptome profile was noted, providing information on potential new biomarkers (non-coding RNAs) with diagnostic and prognostic features. The cells showed different sensitivity to vemurafenib and trametinib. Conclusion Obtained and characterized cellular models of stromal-like cells derived from histiocytic lesions can be used for studies on histiocytosis biology and drug testing

Comparative Genomic Hybridization to Microarrays in Fetuses with High-Risk Prenatal Indications: Polish Experience with 7400 Pregnancies

The aim of this study was to determine the suitability of the comparative genomic hybridization to microarray (aCGH) technique for prenatal diagnosis, but also to assess the frequency of chromosomal aberrations that may lead to fetal malformations but are not included in the diagnostic report. We present the results of the aCGH in a cohort of 7400 prenatal cases, indicated for invasive testing due to ultrasound abnormalities, high-risk for serum screening, thickened nuchal translucency, family history of genetic abnormalities or congenital abnormalities, and advanced maternal age (AMA). The overall chromosomal aberration detection rate was 27.2% (2010/7400), including 71.2% (1431/2010) of numerical aberrations and 28.8% (579/2010) of structural aberrations. Additionally, the detection rate of clinically significant copy number variants (CNVs) was 6.8% (505/7400) and 0.7% (57/7400) for variants of unknown clinical significance. The detection rate of clinically significant submicroscopic CNVs was 7.9% (334/4204) for fetuses with structural anomalies, 5.4% (18/336) in AMA, 3.1% (22/713) in the group of abnormal serum screening and 6.1% (131/2147) in other indications. Using the aCGH method, it was possible to assess the frequency of pathogenic chromosomal aberrations, of likely pathogenic and of uncertain clinical significance, in the groups of cases with different indications for an invasive test