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There are differences in the clinical course of chronic viral hepatitis C between adults and children, but it is generally accepted that the disease has cell-mediated immune background. The aim of this study was to evaluate PBMC subsets in children with chronic hepatitis C before treatment in order to find some predictive factors, useful for patients management. Several PBMC subsets, in particular lymphoid and dendritic cell (DC) ones, were tested by flow cytometry in HCV+ paediatric patients ( n = 46) and in control children matched in terms of age and sex ( n = 20). Data were subjected to extensive statistics. It was found that cells with cytotoxic potential such as CD8+CD28– T cells, NK and NKT cells as well as lineage–HLA-DR+ DC were increased in per cent values, while CD4+ T cells and CD4:CD8 ratio were decreased in hepatitis C group. In HCV+ patients, CD4+ T cells were inversely correlated with alanine aminotransferase (ALT) levels and with viraemia. DC subset of myeloid origin (CD11c+) assessed both in per cent values and as mean fluorescence intensity (MFI) of HLA-DR expression was shown to be downregulated in hepatitis patients, in spite of increased numbers. To conclude, PBMC subsets, and in particular DC, are affected by HCV chronic infection in children, reflected by the correlation with clinical parameters, such as ALT and viraemia. [ABSTRACT FROM AUTHOR]

Enhanced green fluorescent protein (EGFP) is a novel marker gene product, which is readily detectable using techniques of fluorescence microscopy, flow cytometry, or macroscopic imaging. In the present studies, we have examined the immunogenicity of EGFP in murine models. A stable transfectant of the transplantable CMS4 sarcoma of BALB/c origin expressing EGFP, CMS4-EGFP-Zeo, was generated. Splenocytes harvested from mice immunized with a recombinant adenovirus expressing EGFP (Ad-EGFP) were restimulated in vitro with CMS4-EGFP-Zeo. Effector lymphocytes displayed strong cytotoxicity against CMS4-EGFPZeo, but not against mock-transfected CMS4-Zeo tumor cells. A number of candidate H2-K[sup d]-binding peptides derived from the EGFP protein were chosen according to an epitope prediction program and synthesized. These peptides were tested for their ability to bind to H2-K[sup d] molecules and stimulate IFNγ-production by splenocytes harvested from AdEGFP-immunized mice. Using this methodology, the peptide, HYLSTQSAL (corresponding to EGFP[sub 200-208]) which strongly binds to H2-K[sup d] molecules, was identified as a naturally occurring epitope of EGFP. These results should facilitate the use of EGFP as a model tumor antigen in BALB/c mice. [ABSTRACT FROM AUTHOR]

Summary. Thirty-five patients with dermatophyte onychomycosis caused by Trichophyton rubrum , T. mentagrophytes var. granulosum , T. tonsurans and Epidermophyton floccosum were examined before treatment and 27 of these patients were examined again when they came to the control check up 3 months after completion of treatment. The immunological investigations, including evaluation of immunological competence, were performed in vivo through the determination of lymphoid cell immunophenotype by a flow cytometry technique. The quantitative composition of basic lymphocyte subpopulations and natural killer cells in the peripheral blood of 35 patients before the treatment was compared with a control group of 20 individuals. Statistically significant differences in the percentages of CD3+ T lymphocytes (P < 0.05), T helper lymphocytes (CD4+ ) (P < 0.05) and activated T lymphocytes (CD3+ /HLA-DR+ ) (P < 0.05) were obtained. In the control check-up examinations of 27 patients 3 months after completion of treatment, in comparison with the control group of 20 healthy individuals, highly statistically significant differences in percentages of T lymphocytes (CD3+ ) (P < 0.001) and T helper lymphocytes (CD4+ ) (P < 0.01) were obtained. In five of these 27 patients the treatment resulted in failure. Comparing the group of 22 recovered patients with these five patients in whom the treatment result was failure, the only statistically significant difference obtained before as well as after the treatment was in B lymphocytes (CD19+ ) percentage (P < 0.05). The results obtained confirm that impairments of the patients' cellular immunity are crucial factors influencing the course and results of treatment in dermatophyte onychomycosis. [ABSTRACT FROM AUTHOR]

Regulatory T cells (Tregs) represent a small subpopulation of CD4+ cells. Tregs are characterized by the expression of transcription factor Forkhead box protein 3 (FoxP3), also known as scurfin. Tregs are modulators of adaptive immune responses and play an important role in maintaining tolerance to self-antigens, providing the suppression associated with tumour microenvironment as well. These immunomodulatory properties are the main reason for the development of numerous therapeutic strategies, designed to inhibit the activity of cancer cells. However, due to Treg subpopulation diversity and its many functional pathways, the role of these cells in the cancer development and progression is still not fully understood. [ABSTRACT FROM AUTHOR]

Many different cells produce and release membraneous microvesicles ( MV) or exosomes into their microenvironment. Exosomes represent a specific subtype of secreted derived vesicles which are defined as homogenous vesicles of 30-100 nm lined by a lipid bilayer, which contain a specific set of proteins, lipids, and nucleic acids. There are clear evidences that they serve as important biological signals messengers and carriers in physiological as well as in pathological processes. Those derived from tumours (tumour-derived exosomes, TD-exosomes) function as protumourigenic factors that can mediate intercellular communication in the tumour microenvironment and also contribute to cancer progression. The main functions of exosomes in the cancer microenvironment include the following: promotion of primary cancer growth, stimulation of angiogenesis, activation of stromal fibroblasts, sculpting the cancer ECM, generation of a premetastatic niche and suppression of host immune response. Exosomes have recently emerged as potentially promising diagnostic and prognostic biomarkers in cancer and other diseases. This article is a summary of information about the structure and origin of exosomes and also indicates the importance of exosomes and micro RNAs in lung cancer. The role of exosomes in NSCLC is little known, and its explanation requires thorough research. [ABSTRACT FROM AUTHOR]

Background: The CD3+56+ cells are a small but significant population of T lymphocytes encompassing NKT-like and NKT cells, which may play the essential role at the very early stages of atherosclerotic plaque development. The frequency and activity of CD3+56+ cells in atherosclerosis-inducing dysglycaemic disease (diabetes type 2 or prediabetes) is largely unknown. Methods: We analysed CD3+56+ cell count, granzyme, perforin and annexin V profiles in the peripheral blood from a group of patients with pre-diabetes, with diabetes type 2 and from nondysglycaemic controls. Measurements were made of fasting glucose levels, HbA 1 c, 1,5-anhydroglucitol and lipid profile. Results: The mean counts of CD3+56+ cells were significantly higher in patients with pre-diabetes compared to both patients with diabetes and to control group. There was an increase in the number of CD3+56+ cells producing granzyme and perforin in pre-diabetic patients compared to other groups, while there were no difference in annexin V+ populations within examined groups. It was confirmed that CD3+56+ cells count is modified by metabolic factors and their parameters, namely HbA 1 c and 1,5-anhydroglucitol values. Conclusion: It could be stated that the alterations of CD3+56+ cells count in peripheral blood of pre-diabetic and type 2 diabetic patients are related to different grades of carbohydrate deteriorations - postprandial hyperglycaemia and chronic hyperglycaemia. [ABSTRACT FROM AUTHOR]

Prolactin (PRL) has been reported to inhibit apoptosis in various cell types and to serve as a cofactor in the upregulation of CD25 on T cells during activation. We investigated a possible relation between prolactin receptor (PRL-R) or IL-2 receptor alpha (IL-2Ralpha, CD25) expression on circulating T lymphocytes and their apoptosis in patients with breast cancer. Peripheral blood mononuclear cells obtained from 25 patients, 25 normal controls (NC) and three cord blood samples were evaluated for Annexin V binding and expression of CD95, CD25, and PRL-R on CD3(+) T cells by multicolour flow cytometry. Plasma levels of PRL, sCD95L, and sIL-2R were determined in patients and controls and related to T-cell apoptosis. The ability of PRL to protect T cells from apoptosis induced by various agents was also studied. Expression of PRL-R on the surface of T cells was comparable in patients with breast cancer and NC, but PRL plasma levels in patients were significantly lower (P<0.05). In patients, 18+/-11% (mean+/-s.d.) of CD3(+) cells bound Annexin V, compared to 9+/-6% in NC (P<0.0004). Percentages of CD3(+)Fas(+) and CD3(+)CD25(+) cells were higher in the peripheral circulation of patients than NC (P<0.0001 and <0.04, respectively). Levels of sFasL were lowest in plasma of the patients with the highest proportions of CD3(+)Fas(+) T cells. Most T cells undergoing apoptosis were CD3(+)CD25(-) in patients, and the proportion of CD3(+)CD25(-) Annexin V(+) cells was significantly increased in patients compared to NC (P<0.006). Ex vivo PRL protected T cells from starvation-induced or anti-CD3Ab-induced but not from Fas/FasL-dependent apoptosis. These results indicate that expression of CD25 but not of PRL-R on the surface of activated T lymphocytes appears to be involved in modulating Fas/Fas - ligand interactions, which are, in part, responsible for apoptosis of T lymphocytes and excessive turnover of immune cells in the circulation of patients with breast cancer. [ABSTRACT FROM AUTHOR]

Leu-19 (CD56) MoAb is well known to recognize gp220 expressed on natural killer (NK) cells and is widely used as a NK cell marker. The expression of CD56 antigen was tested by means of sensitive alkaline phosphatase-anti-alkaline phosphatase (APAAP) immunohistochemical technique and the above mentioned MoAb as a primary antibody, on frozen sections of various fresh human tissues. Out of 11 organs examined only thyroid gland provided a distinct reaction confined to cell membranes of epithelial follicular cells. The reaction had a diffuse pattern in cases of Graves' disease and colloidal goitre while in Hashimoto's thyroiditis presented as a focal pattern. Other anti-NK cell MoAbs such as VD4 (CD 16) and Leu-7(CD57) reacted only with single cells of thyroid stroma. The results of APAAP staining were confirmed by the cytofluorimetric assessment of isolated thyroid cells. It is speculated that CD56 expression on thyroid cells may have a functional significance, perhaps related to neural-endocrine interactions. [ABSTRACT FROM AUTHOR]