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Journal Article 2010; 31(Suppl 2): 11-15 PubMed PMID: 21187820 Citation  Keywords:  Animals, Annexin A5:metabolism, Apoptosis:drug effects, Carps:metabolism, Caspases:metabolism, Cell Survival:drug effects, Dose-Response Relationship, Drug, Immune System:cytology, L-Lactate Dehydrogenase:metabolism, Lymphocytes:cytology, Models, Animal, .   

OBJECTIVES: The aim of this study was to assess the possible in vitro apoptotic effects of anatoxin-a on the selected immune cells isolated from the blood of carp.

DESIGN: In the experiments pure anatoxin-a was used at concentrations of 0.01, 0.05, 0.1 and 1 µg/ml RPMI-1640 medium. Apoptosis or necrosis of fish leukocytes (lymphocytes and phagocytes) induced by the toxin was determined by measurement of the activity of caspases-3/7 and the analysis of phosphatidylserine on the outer leaflet of apoptotic cell-membranes using Annexin-V-Fluorescein and Propidium Iodide. Moreover, fluorescent measurement of the release of lactate dehydrogenase from the cells with damaged membranes was done.

RESULTS: The viability of the lymphocytes exposed only to the highest concentration of anatoxin-a (1 µg/ml) was significantly decreased. The exposure to the toxin at higher concentrations (0.1 and 1 µg/ml) resulted in a significant increase of caspases 3/7 activity in phagocytes and lymphocytes. Moreover, fluorescent analysis with the use of annexin-V-fluorescein and propidium iodide staining showed more cells at the apoptotic stage than necrotic cells.

CONCLUSION: Our study showed that anatoxin-a is an inducer of apoptosis in fish immune cells....

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Journal Article 2009; 30(6): 761-768 PubMed PMID: 20038927 Citation  Keywords:  Acoustic Stimulation, Age Factors, Animals, Animals, Newborn, Anxiety, Separation:immunology, Apoptosis:immunology, Body Weight, Cells, Cultured, Corticosterone:blood, Disease Models, Animal, Female, Immune Tolerance:physiology, Lymphocytes:cytology, Male.   

OBJECTIVES: Different inbred mouse strains but also each animal of the same strain show an individually different stress response which is influenced by genetic and environmental factors such as early life experiences. In this study, we investigated consequences of mild postnatal stress exposure on the stress coping style of adult BALB/c mice.

METHODS: We used a model of mild early life stress where neonatal mice were repeatedly separated from the dam staying with their siblings for 1-h each day during the first two postnatal weeks. The environment during maternal separation was adapted to the nest (bedding, 37 degrees C warm).

RESULTS: Adult female BALB/s mice that underwent the maternal separation protocol or were not isolated from the dam in early life were exposed to combined acoustic and restraint stress in adulthood. Repeated maternal separation which was performed under ambient conditions increased the stress coping ability of mice at the age of 12 weeks when exposed to this psychological stressors. By acoustic and restraint stress-induced alterations such as high corticosterone levels, an anti-inflammatory immune conditioning with an ex vivo hyperinducibility of interleukin-10 of splenocytes and a massive loss of body weight were significantly reduced in the maternally separated group compared with conventionally bred control mice.

CONCLUSIONS: Mild maternal separation in early life modifies the stress coping style of adult female BALB/c mice to a more stress-resistant phenotype which shows reduced repeated stress-induced immune suppression and weight loss and is linked to reduced release of glucocorticoids after stress exposure....

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Journal Article 2009; 30(3): 275-283 PubMed PMID: 19855349 Citation  Keywords:  Cell Differentiation, Cell Shape, Dendritic Cells:cytology, Epithelial Cells:cytology, Humans, Macrophages:cytology, T-Lymphocytes:cytology, Thymus Gland:cytology,.   

: The thymus is the central organ of the immune system. It is essential for the development and maintenance of normal immune system, especially cell-mediated immunity. From the morphological point of view, the thymus is divided into two main compartments, cortex and medulla. The thymic microenvironment consists of a network of reticular epithelial cells and other fixed and free cells. The microenvironment of thymus is very important for the selection and maturation of T cells. T cell differentiation occurs via T cell receptors. The major histocompatibility complex participates in interactions between T cells and thymic epithelial cells, in addition to interactions between T cells and dendritic cells, macrophages and myoid cells. The neuroendocrine system regulates early T cell differentiation by the transcription of neuroendocrine genes in the stromal network and expression of cognitive receptors by immature T cells. This work briefly summarizes morphological and ultrastructural characteristics of thymic epithelial cells, dendritic cells, macrophages and myoid cells. It is accompanied by the authors' own photomicrographs and electronmicrograph from a transmission electron microscope. All of these cells play a critical role in the proliferation, differentiation and selection of precursor cells in the T-cell lineage, but the precise mechanisms not well understudood....

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Comparative Study 2008; 29(2): 240-245 PubMed PMID: 18404145 Citation  Keywords:  Adult, Aged, CD4 Lymphocyte Count, CD4-Positive T-Lymphocytes:cytology, Case-Control Studies, Female, Flow Cytometry, Humans, Interleukin-2 Receptor alpha Subunit:metabolism, Male, Middle Aged, Neoplasms:blood, Phenotype, Prognosis, Survival Analysis, T-L.   

AIM: Regulatory T cells (Treg) that prevent autoimmune diseases by suppression of self-reactive T cells may also suppress the immune response against cancer. Experimental tumor models in mice revealed that Tregs are potent inhibitors of an antitumor immune response. The purpose of the study was to identify a CD4+ population of regulatory T cells expressing high levels of CD25(CD4+CD25 high) in the peripheral blood of cancer patients and provide the opportunity to determine whether cancer patients exhibit an expanded CD4+CD25high pool.

METHODS: The frequency of CD4+CD25high in the peripheral blood of 62 cancer patients and 15 healthy donors was determined by flow cytometry.

RESULTS: Compared with healthy donors, cancer patients have an increasing prevalence of CD4+CD25high T cells in the peripheral blood with characteristics of Tregs, i.e. they are CD45-RA(), CD69(-). Among patients, those with higher percentages of CD4+CD25high T cells had a poor prognosis than did those with lower percentages.

CONCLUSION: We provide evidence of an increased pool of CD4+CD25high in the peripheral blood of cancer patients, which may be related to immunosuppression and tumor progress in cancer patients. This finding suggests that the use of immunomodulatory therapy to treat cancer patients may be an effective strategy....

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Journal Article 2003; 24(5): 329-333 PubMed PMID: 14647006 Citation  Keywords:  Aged, Aging:physiology, Cells, Cultured, Euchromatin:drug effects, Heterochromatin:drug effects, Hot Temperature, Humans, Lymphocytes:cytology, Oligopeptides:pharmacology, Protein Denaturation, Ribosomal Proteins:genetics, Transcriptional Activation:drug .   

UNLABELLED: OBJECTIVES and design. We have studied the effect of synthetic peptide Epitalon on the activity of ribosomal genes, denaturation parameters of total heterochromatin, polymorphism of structural C-heterochromatin and the variability of facultative heterochromatin in cultured lymphocytes of persons aged 76-80 years.

RESULTS: The obtained data demonstrate that Epitalon induces the activation of ribosomal genes, decondensation of pericentromeric structural heterochromatin and the release of genes repressed due to the age-related condensation of euchromatic chromosome regions.

CONCLUSIONS: Epitalon has shown its ability to activate chromatin by modifying heterochromatin and heterochromatinized chromosome regions in the cells of older persons....

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