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Sample records for adapted human lymphocytes

  1. Cytogenetic radiation adaptive response assessed by metaphase analysis and micronuclei test in human lymphocytes and mouse bone marrow cells

    International Nuclear Information System (INIS)

    Radiation adaptive response in human peripheral lymphocytes and mouse bone marrow cells was investigated using both metaphase analysis and micronucleus assay. We assessed the correlation between both tests. Two groups of the human peripheral lymphocytes and mouse bone marrow cells were exposed to low dose (conditioning dose, 0.18 Gy) or high dose (challenging dose, 2 Gy) Υ-rays. The other 4 groups were exposed to low dose followed by high dose after several time intervals (4, 7, 12, and 24 hours, respectively). The frequencies of chromosomal aberrations in metaphase analysis and micronuclei in micronucleus assay were counted. Chromosomal aberrations and micronuclei of preexposed group were lower than those of the group only exposed to high dose radiation. Maximal reduction in frequencies of chromosomal aberrations were observed in the group to which challenging dose was given at 7 hour after a conditioning dose (p<0.001). Metaphase analysis and micronucleus assay revealed very good correlation in both human lymphocytes and mouse bone marrow cells (r=0.98, p<0.001; r=0.99, p=0.001, respectively). Radiation adaptive response could be induced by low dose irradiation in both human lymphocytes and mouse bone marrow cells. There was a significant correlation between metaphase analysis and micronucleus assay

  2. Alarm signal transduction and DNA repair in the adaptive response induced by X-rays in human lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Wojewodzka, M.; Kruszewski, M.; Szumiel, I.; Wojcik, A. [Institute of Nuclear Chemistry and Technology, Warsaw (Poland); Staffer, C. [Universitatklinikum, Essen (Germany); Gasinska, A. [Radiotherapy Clinic Oncology Center, Cracow (Poland)

    1995-12-31

    Irradiation of human lymphocytes (1 cGy, 37 deg C) evoked a 30% decrease in the frequency of micronuclei upon subsequent X-irradiation (1.5 Gy). The response was reflected both by a reduction in the formation of micronuclei frequency and in an increase in the DNA repair rate measured by the comet assay directly after the challenge dose. The calcium antagonist, TMB-8, and staurosporine, an inhibitor of protein kinases, prevented the development of the adaptive response measured by the appearance of micronuclei. Psi-tectorigenin, an inhibitor of phosphatidylinositol turnover, did not modify the adaptive response. The induction of adaptation as not accompanied by altered progression through the cell cycle, or changes in chromatin condensation as determined by flow cytometry (DNA content and 90 deg side scatter, respectively). (author). 24 refs, 8 figs.

  3. Opinion: Interactions of innate and adaptive lymphocytes

    OpenAIRE

    Gasteiger, Georg; Rudensky, Alexander Y.

    2014-01-01

    Innate lymphocytes, including natural killer (NK) cells and the recently discovered innate lymphoid cells (ILCs) have crucial roles during infection, tissue injury and inflammation. Innate signals regulate the activation and homeostasis of innate lymphocytes. Less well understood is the contribution of the adaptive immune system to the orchestration of innate lymphocyte responses. We review our current understanding of the interactions between adaptive and innate lymphocytes, and propose a mo...

  4. The adaptive response of human lymphocytes to very low doses of ionizing radiation: a case of induced chromosomal repair with the induction of specific proteins

    International Nuclear Information System (INIS)

    It appears that the adaptive response of human lymphocytes to low doses of X-rays can be mimicked by exposure to low levels of a truly radiomimetic compound, bleomycin, that induces double-strand breaks in DNA. Similarly, the adaptive response can be induced by exposure to low levels of H2O2, which produces reactive species similar to those induced by ionizing radiation. This adaptive response, which is attributed to the induction of a repair mechanism, i.e. repair enzymes, can be prevented if protein synthesis, and thus enzyme synthesis, is inhibited by cycloheximide at the crucial time (4-6 h) after exposure to the adaptive dose. Two-dimensional gel electrophoresis has shown that 1 cGy of X-rays can reproducibly induce several proteins not found in unirradiated lymphocytes. These proteins are considered to be excellent candidates for the actual repair enzyme(s). (author)

  5. Differences in the adaptive response to radiation damage in G0 human lymphocytes conditioned with hydrogen peroxide or low-dose X-rays

    International Nuclear Information System (INIS)

    We have carried out experiments to study the adaptive response in G0 human lymphocytes conditioned with either hydrogen peroxide or low-dose X-rays and challenged with 1.5 Gy of X-rays after stimulation. Peroxide conditioning treatment was given at different times before stimulation, while the low-dose irradiation was delivered at different dose rates just before stimulation of lymphocytes. A protective effect of pre-exposure to H2O2 against radiation damage detected as micronuclei in binucleated cells was evident, regardless of the time of conditioning treatment during G0. For low-dose-irradiated cells, on the other hand, the adaptation observed seemed to depend upon the dose rate, and never reached the extent observed in cells treated with peroxide

  6. Structure alterations of human lymphocyte nuclei affected by ionizing radiation within the range of doses that cause the adaptive response

    International Nuclear Information System (INIS)

    Low-level radiation either from external or from incorporated sources is shown to cause a nonmonotonous change in some intranuclear parameters of human peripheral blood lymphocytes. For instance, radiation induces changes in the parameters that characterize the location of perecentromeric regions within the interphase nucleus and a nonmonotonous increase in nuclear sizes. The exposure to doses exceeding 5 cGy impairs the realtionship between the nuclear sizes and location therein of the perecentromeric regions of interphase chromosomes which exist in the control and after exposure to 2.5 cGy. Differences between the dose ranges of 1.5-3.5 and 17-25 cGy are manifested by the kinetics of restoration of the pattern of distribution of lymphocyte nuclear sizes

  7. Radiation survival curve parameters for human lymphocytes

    International Nuclear Information System (INIS)

    This paper estimates radiation survival curve parameters for lymphocytes in order to optimize large-field radiation schedules for patients with lymphoma or patients requiring immunosuppression. The authors compared radiation schedules (total body or total lymphoid) used in 12 different studies in dogs, pigs, rhesus monkeys, or human patients. Different radiation schedules should cause the same survival fraction for lymphocytes if results are similar and cause at least a threefold difference in survival fractions if results are dissimilar. By trial and error, the best extrapolation number (n) and D0 can be selected for each data set by using the single-hit, multiple-target model. Data sets are best explained by postulating an n of 1.25-1.50 and a D0 of 1.5 Gy for malignant (B lymphocytes) or normal lymphocytes. Both are higher than previous estimates made by other investigators determining lymphocyte numbers in peripheral blood after radiation exposure or by using radiation conditions unrealistic for human patients that can be achieved only in small rodents

  8. Oxidative stress as a significant factor for development of an adaptive response in irradiated and nonirradiated human lymphocytes after inducing the bystander effect by low-dose X-radiation

    Energy Technology Data Exchange (ETDEWEB)

    Ermakov, Aleksei V., E-mail: avePlato@mail.ru [Research Centre for Medical Genetics, Russian Academy of Medical Science, ul. Moskvorechye, 1, Moscow 115478 (Russian Federation); Konkova, Marina S.; Kostyuk, Svetlana V.; Egolina, Natalya A.; Efremova, Liudmila V.; Veiko, Natalya N. [Research Centre for Medical Genetics, Russian Academy of Medical Science, ul. Moskvorechye, 1, Moscow 115478 (Russian Federation)

    2009-10-02

    X-radiation (10 cGy) was shown to induce in human lymphocytes transposition of homologous chromosomes loci from the membrane towards the centre of the nucleus and activation of the chromosomal nucleolus-forming regions (NFRs). These effects are transmitted by means of extracellular DNA (ecDNA) fragments to nonirradiated cells (the so-called bystander effect, BE). We demonstrated that in the development of the BE an important role is played by oxidative stress (which is brought about by low radiation doses and ecDNA fragments of the culture medium of the irradiated cells), by an enzyme of apoptosis called caspase-3, and by DNA-binding receptors of the bystander cells, presumably TLR9. Proposed herein is a scheme of the development of an adaptive response and the BE on exposure to radiation. Ionizing radiation induces apoptosis of the radiosensitive fraction of cells due to the development of the 'primary' oxidative stress (OS). DNA fragments of apoptotic cells are released into the intercellular space and interact with the DNA-binding receptors of the bystander cells. This interaction activates in lymphocytes signalling pathways associated with synthesis of the reactive oxygen species and nitrogen species, i.e., induces secondary oxidative stress accompanied by apoptosis of part of the cells, etc. Hence, single exposure to radiation may be followed by relatively long-lasting in the cellular population oxidative stress contributing to the development of an adaptive response. We thus believe that ecDNA of irradiated apoptotic lymphocytes is a significant factor of stress-signalling.

  9. Immunophenotypic lymphocyte profiles in human african trypanosomiasis.

    Directory of Open Access Journals (Sweden)

    Caroline Boda

    Full Text Available Human African trypanosomiasis (HAT is a deadly vector-born disease caused by an extracellular parasite, the trypanosome. Little is known about the cellular immune responses elicited by this parasite in humans. We used multiparameter flow cytometry to characterize leukocyte immunophenotypes in the blood and cerebrospinal fluid (CSF of 33 HAT patients and 27 healthy controls identified during a screening campaign in Angola and Gabon. We evaluated the subsets and activation markers of B and T lymphocytes. Patients had a higher percentage of CD19+ B lymphocytes and activated B lymphocytes in the blood than did controls, but lacked activated CD4+ T lymphocytes (CD25+. Patients displayed no increase in the percentage of activated CD8+ T cells (HLA-DR+, CD69+ or CD25+, but memory CD8 T-cell levels (CD8+CD45RA2 were significantly lower in patients than in controls, as were effector CD8 T-cell levels (CD8+CD45RA+CD62L2. No relationship was found between these blood immunophenotypes and disease severity (stage 1 vs 2. However, CD19+ B-cell levels in the CSF increased with disease severity. The patterns of T and B cell activation in HAT patients suggest that immunomodulatory mechanisms may operate during infection. Determinations of CD19+ B-cell levels in the CSF could improve disease staging.

  10. Analysis in cytokinesis-blocked human lymphocytes

    International Nuclear Information System (INIS)

    Biological dosimetry can be considered as an additional method to physical dosimetry for estimating dose absorption after exposure to ionizing radiation. Fully validated as well as new promising approaches in this field are reviewed. Recent experiments, carried out in our laboratory, on the analysis of micronuclei in cytokinesis-blocked human lymphocytes are presented. The possible relevance of differential human individual response to ionizing radiation, in view of the occurrence of radiosensitive syndromes, for the estimation of the absorbed dose in human is also discussed

  11. Introduction of micronuclei in human irradiated lymphocytes

    International Nuclear Information System (INIS)

    The appearance of micronuclei (MN) was induced in human blood lymphocytes to establish the existence of a dose-response relationship between radiation and micronucleus frequency and determine the lowest radiation dose that can be valued by the micronucleus assay. To do so, two different types of experiment were conducted: a) induction of micronuclei in human lymphocytes by gamma radiation ''in vitro''; b) induction of micronuclei in human lymphocytes whit low doses of X-rays ''in vitro''. Statistically, a linear-quadratic dependency relationship was found (y=K+alpha.D-Beta.D''2) between the number of micronuclei and the doses of radiation administered. The lowest dose that can be value by the micronucleus assay could be established as 4-16 cGy depending on the criteria used for determination. The micronucleus assay is a useful and simple test to determine the dose-response relationship, thus enabling it to be applied as a biological dosimeter in situations where physical dosimetry is not possible or is absent. (Author) 35 refs

  12. DNA repair in PHA stimulated human lymphocytes

    International Nuclear Information System (INIS)

    Damage an repair of radiation induced DNA strand breaks were measured by alkaline lysis and hydroxyapatite chromatography. PHA stimulated human lymphocytes show that the rejoining process is complete within the first 50 min., afterwords secondary DNA damage and chromatid aberration. DNA repair, in synchronized culture, allows to evaluate individual repair capacity and this in turn can contribute to the discovery of individual who, although they do not demonstrate apparent clinical signs, are carriers of DNA repair deficiency. Being evident that a correlation exists between DNA repair capacity and carcinogenesis, the possibility of evaluating the existent relationship between DNA repair and survival in tumor cells comes therefore into discussion

  13. Long intergenic noncoding RNAs: novel drivers of human lymphocyte differentiation

    Directory of Open Access Journals (Sweden)

    Ilaria ePanzeri

    2015-04-01

    Full Text Available Upon recognition of a foreign antigen, CD4+ naïve T lymphocytes proliferate and differentiate into subsets with distinct functions. This process is fundamental for the proper immune system function, as CD4+ T cells orchestrate both the innate and adaptive immune response. Traditionally, this differentiation event has been regarded as the acquisition of an irreversible cell fate so that memory and effector CD4+ T subsets were considered terminally differentiated cells or lineages. Consequently, these lineages are conventionally defined thanks to their prototypical set of cytokines and transcription factors. However, recent findings suggest that CD4+ T lymphocytes possess a remarkable phenotypic plasticity, as they can often redirect their functional program depending on the milieu they encounter. Therefore new questions are now compelling such as which are the molecular determinants underlying plasticity and stability and how the balance between these two opposite forces drives the cell fate. As already mentioned, in some cases the mere expression of cytokines and master regulators could not fully explain lymphocytes plasticity. We should consider other layers of regulation, including epigenetic factors such as the modulation of chromatin state or the transcription of noncoding RNAs, whose high cell-specificity give a hint on their involvement in cell fate determination. In this review, we will focus on the recent advances in understanding CD4+ T lymphocytes subsets specification from an epigenetic point of view. In particular, we will emphasize the emerging importance of noncoding RNAs as key players in these differentiation events. We will also present here new data from our laboratory highlighting the contribution of long noncoding RNAs in driving human CD4+ T lymphocytes differentiation.

  14. Aryl hydrocarbon mono-oxygenase activity in human lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, G.D.; Schuresko, D.D.

    1981-06-01

    Aryl hydrocarbon mono-oxygenase (AHM), an enzyme of key importance in metabolism of xenobiotic chemicals such as polynuclear aromatic hydrocarbons (PNA), is present in human lymphocytes. Studies investing the relation of activity of AHM in human lymphocytes to parameters such as disease state, PNA exposure, in vitro mitogen stimulation, etc. have been summarized in this report. Some studies have demonstrated increased AHM activity in lymphocytes from cigarette smokers (compared to nonsmokers), and in lung cancer patients when compared to appropriate control groups. These observations are confused by extreme variability in human lymphocyte AHM activities, such variability arising from factors such as genetic variation in AHM activity, variation in in vitro culture conditions which affect AHM activity, and the problematical relationship of common AHM assays to actual PNA metabolism taking place in lymphocytes. If some of the foregoing problems can be adequately addressed, lymphocyte AHM activity could hold the promise of being a useful biomarker system for human PNA exposure.

  15. Effects of budlein A on human neutrophils and lymphocytes

    Science.gov (United States)

    KNOB, Carollinie Dias; SILVA, Milena; GASPAROTO, Thaís Helena; OLIVEIRA, Carine Ervolino; AMÔR, Nádia Ghinelli; ARAKAWA, Nilton Syogo; COSTA, Fernando Batista; CAMPANELLI, Ana Paula

    2016-01-01

    ABSTRACT Sesquiterpene lactones (SLs) are the active constituents of a variety of medicinal plants used in traditional medicine for the treatment of inflammatory diseases and other ailments. Objective In this study, we evaluated whether budlein A modulates the activation of innate and adaptive immune cells such as neutrophils and lymphocytes. Material and Methods Our research group has investigated several plant species and several compounds have been isolated, identified, and their medical potential evaluated. Budlein A is a SL isolated from the species Aldama buddlejiformis and A. robusta (Asteraceae) and shows anti-inflammatory and anti-nociceptive activities. Advances in understanding how plant-derived substances modulate the activation of innate and adaptive immune cells have led to the development of new therapies for human diseases. Results Budlein A inhibited MPO activity, IL-6, CXCL8, IL-10, and IL-12 production and induces neutrophil apoptosis. In contrast, budlein A inhibited lymphocyte proliferation and IL-2, IL-10, TGF-β, and IFN-γ production, but it did not lead to cell death. Conclusions Collectively, our results indicate that budlein A shows distinct immunomodulatory effects on immune cells. PMID:27383709

  16. Predictive radiosensitivity tests in human lymphocytes

    International Nuclear Information System (INIS)

    Individual radiosensitivity is an inherent characteristic, associated with an abnormally increased reaction to ionising radiation of both the whole body and cells derived from body tissues. Human population is not uniform in its radiation sensitivity. Radiosensitive sub-groups exist, which would suffer an increased incidence of both deterministic and stochastic effects. Clinical studies have suggested that a large part of the spectrum of normal tissue reaction may be due to differences in individual radiosensitivity. The identification of such sub-groups should be relevant for radiation therapy and radiation protection purposes. It is suggested that DNA repair mechanisms are involved. Consequently, the characterization of DNA repair in lymphocytes through cytokinesis blocked micronucleus (MN) and alkaline single-cell microgel electrophoresis (comet) assays could be a suitable approache to evaluate individual radiosensitivity in vitro. The aims of this study were: 1) To assess the in vitro radiosensitivity of peripheral blood lymphocytes from two groups of cancer patients (prospectively and retrospectively studied), using MN and comet assays, in comparison with the clinical radiation reaction and 2) To test the predictive potential of both techniques for the identification of radiosensitivity sub-groups. 38 cancer patients receiving radiation therapy were enrolled in this study. 19 patients were evaluated prior, mid-way and on completion of treatment (prospective group) and 19 patients were evaluated about 6-18 month after radiotherapy (retrospective group). Cytogenetic data from the prospective group were analysed using a mathematical model to evaluate the attenuation of the cytogenetic effect as a function of the time between a single exposure and blood sampling, estimating a cytogenetic recovery factor k. In the retrospective group, blood samples were irradiated in vitro with 0 (control) or 2 Gy and evaluated using MN test. Cytogenetic data were analysed

  17. THE ADAPTABLE CHANGE OF THE FUNCTION OF T LYMPHOCYTES FOR PHYSICAL EXERCISE WITH OXYGEN

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective To find out the possible regularity and mechanism of the adaptable change of human being T lymphocytes for physical exercise with oxygen and bring the original data for the Movement of All People Improving their Health. Methods We selected 16 untrained female students in university and let them had the same amount of exercise for 8 weeks. After that, we collected the cycle blood at the time point of before exercise, the end of exercise and 1 hour after exercise at the end of the 0,first,2 nd,4 nd,6 nd and 8 nd week respectively, so as to determine its stimuli index (SI) by MTT method. Results In the different time sect, such as the early stage of exercise, quiet condition,as soon as the end of exercise and 1 hour after exercise, we found that the SI were obviously Iower than that of normal (P<0. 05) ,especially in the time sect of the end of exercise. Continuing to 4 weeks,the function of T lymphocytes restored gradualy and it lasted to the 8 th week, the SI in quiet condition and 1 hour after exercise had restored to normal(P>0.05),but in the end of exercise, it still was Iow,however, the extent of the cases selected was in a condition of acute excitability. Conclusion As the bodies adapting to the exercise, the function of T lymphocytes restored slowly and the rate increased faster and faster.

  18. Spontaneous unscheduled DNA synthesis in human lymphocytes

    International Nuclear Information System (INIS)

    The rate of spontaneous unscheduled DNA synthesis in human lymphocytes was estimated from measurements of tritiated thymidine incorporation into double-stranded DNA (ds-DNA) during incubation of cells in vitro. The contribution of scheduled DNA synthesis to the observed incorporation was reduced by inhibiting replication with hydroxyurea and by separating freshly replicated single-stranded DNA (ss-DNA) from repaired ds-DNA by column chromatography. The residual contribution of scheduled DNA synthesis was estimated by observing effects on thymidine incorporation of: (a) increasing the rate of production of apurinic sites, and alternatively, (b) increasing the number of cells in S-phase. Corrections based on estimates of endogenous pool size were also made. The rate of spontaneous unscheduled DNA synthesis is estimated to be 490 +- 120 thymidine molecules incorporated per cell per hour. These results compare favorably with estimates made from rates of depurination and depyrimidination of DNA, measured in molecular systems if we assume thymidine is incorporated by a short patch mechanism which incorporates an average of four bases per lesion

  19. The nature of the refractive granules in human lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Knowlton, N.P. Jr.; Hempelmann, L.H. [Los Alamos Scientific Lab., NM (United States)

    1949-04-19

    The number of refractive bodies in human lymphocytes increases in persons chronically exposed to low level doses of ionizing radiation. The observations of the optical properties, the histochemistry, and the method of formation of these bodies are described.

  20. Human lymphocytes response to low gamma-ray doses

    International Nuclear Information System (INIS)

    Radiation and non-radiation workers lymphocytes were exposed to a low strength gamma-ray field to determine heat shock protein expression in function of radiation dose. Protein identification was carried out using mAb raised against Hsp25, Hsp60, Hsp70 and Hsp90; from these, only Hsp70 protein was detected before and after lymphocyte irradiation. In all cases, an increasing trend of relative amounts of Hsp70 in function to irradiation time was observed. After 70.5 μGy gamma-ray dose, radiation worker's lymphocytes expressed more Hsp70 protein, than non radiation workers' lymphocytes, indicating a larger tolerance to gamma rays (gammatolerance), due to an adaptation process developed by his labor condition

  1. Response of human lymphocytes to low gamma ray doses

    International Nuclear Information System (INIS)

    Radiation and non-radiation workers lymphocytes were exposed to a low strength gamma-ray field to determine heat shock protein expression in function of radiation dose. Protein identification was carried out using mAb raised against Hsp25, Hsp60, Hsp70 and Hsp90; from these, only Hsp70 protein was detected before and after lymphocyte irradiation. In all cases, an increasing trend of relative amounts of Hsp70 in function to irradiation time was observed. After 70.5 mGy gamma-ray dose, radiation worker's lymphocytes expressed more Hsp70 protein, than non-radiation workers' lymphocytes, indicating a larger tolerance to gamma rays (gamma tolerance), due to an adaptation process developed by their labor condition (Au)

  2. Genotoxicity of the herbicide butachlor in cultured human lymphocytes.

    Science.gov (United States)

    Sinha, S; Panneerselvam, N; Shanmugam, G

    1995-08-01

    Butachlor, a pre-emergence herbicide was investigated for its ability to induce sister chromatid exchanges (SCE) and chromosome aberrations (CA) in cultured human peripheral blood lymphocytes. Mitogen-stimulated lymphocytes were treated with three different concentrations (5, 10 and 20 micrograms/ml) of butachlor for 24, 48 and 72 h. Our results indicate a dose-dependent increase in the frequency of chromosomal aberrations at 24, 48 and 72 h of treatment with butachlor. No SCE was promoted by butachlor.

  3. Effect of praziquantel on human lymphocyte proliferation in vitro

    DEFF Research Database (Denmark)

    Odum, Niels; Theander, T G; Bygbjerg, I C

    1984-01-01

    The antischistosomal drugs tartar emetic and niridazole exert immunosuppression both in vitro and in vivo. In the present study the influence of praziquantel (Biltricide), a potent schistosomicidal drug, on human lymphocyte proliferation in vitro was investigated. Praziquantel 80 micrograms....../ml significantly reduced thymidine incorporation by human blood mononuclear cells stimulated with mitogens and antigens, whereas no effect could be detected in concentrations below 40 micrograms/ml. Thus, praziquantel, in concentrations as high as 30 times the peak serum concentration during therapy, has...... no suppressive effect on human lymphocyte proliferation in vitro....

  4. Interaction of nanosilver particles with human lymphocyte cells

    Science.gov (United States)

    Zhornik, Alena; Baranova, Ludmila; Volotovski, Igor; Chizhik, Sergey; Drozd, Elizaveta; Sudas, Margarita; Buu Ngo, Quoc; Chau Nguyen, Hoai; Huynh, Thi Ha; Hien Dao, Trong

    2015-01-01

    The damaging effects of nanoparticles were hypothesized to be the oxidative stress caused by the formation of reactive oxygen species and initiation of inflammatory reactions. In this context a study on the effects of nanosilver particles on the formation of reactive oxygen species in human lymphocyte culture was carried out. The obtained results showed that fluorescence intensity considerably increased after cells had interacted with nanosilver particles of varying concentrations, indicating the formation of reactive oxygen species and their accumulation in lymphocyte cells. Morphological study of the lymphocyte cells under the effects of nanosilver particles showed that the change in morphology depends on the concentration and size of nanosilver particles: for a size ≤20 nm the lymphocyte cell significantly shrank with pronounced differences in the morphological structure of the cell membrane, but for a size ≥200 nm no change was observed.

  5. Radioadaptive response in human B- and CD8{sup +} T-lymphocytes as measured by the acridine orange stained micronuclei technique

    Energy Technology Data Exchange (ETDEWEB)

    Kim, H.S.; Choi, J.M.; Yang, K.H.; Kim, C.S.; Lim, Y.K.; Kim, C.S. [Korea Hydro and Nuclear Power Corporation, Radiation Health Research Institute, Seoul (Korea); Woon, J.H. [National Veterinary Research and Quarantine Service, Anyang (Korea)

    2003-07-01

    To investigate (1) the radiosensitive of B- versus T- lymphocytes and (2) the possible application of their sensitivity for adaptive response after treating with an adapting plus a challenge dose. In the present experiments, micronucleus analysis was performed in B- and CD8{sup +} matured T-lymphocytes of eight healthy volunteers exposed to {gamma}-rays. The number of radio-induced micronuclei was significantly higher in B-lymphocytes compared to T-lymphocytes in the dose range from 10 to 100cGy. To investigate adaptive response, whole blood samples were irradiated in vitro with a pretreatment dose of 1cGy {sup 137}Cs {gamma}-irradiation. Six hours after their initiation, groups of cultures were subsequently exposed to a challenge dose of 100cGy {gamma}-irradiation. Following stimulation with PHA and PWM for T- and B-lymphocyte cultivation, lymphocytes were fixed at 72 hours and stained with acridine orange dye. B-lymphocytes exhibited a greater induction of adaptive response than those of CD8{sup +} matured T-lymphocytes, and when pretreated with 1cGy significantly fewer micronuclei induced by the challenge dose of 100cGy {gamma}-irradiation. The results suggest that the lower dose pretreatments are able to induce a significantly higher adaptive response in human B-lymphocytes, and this adaptive response may result from the DNA repair mechanism, which may lead to less residual damage. (author)

  6. D-ribose inhibits DNA repair synthesis in human lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Zunica, G.; Marini, M.; Brunelli, M.A.; Chiricolo, M.; Franceschi, C.

    1986-07-31

    D-ribose is cytotoxic for quiescent human lymphocytes and severely inhibits their PHA-induced proliferation at concentrations (25-50 mM) at which other simple sugars are ineffective. In order to explain these effects, DNA repair synthesis was evaluated in PHA-stimulated human lymphocytes treated with hydroxyurea and irradiated. D-ribose, in contrast to other reducing sugars, did not induce repair synthesis and therefore did not apparently damage DNA in a direct way, although it markedly inhibited gamma ray-induced repair. Taking into account that lymphocytes must rejoin physiologically-formed DNA strand breaks in order to enter the cell cycle, we suggest that D-ribose exerts its cytotoxic activity by interfering with metabolic pathways critical for the repair of DNA breaks.

  7. Selective effects of alpha interferon on human T-lymphocyte subsets during mixed lymphocyte cultures

    DEFF Research Database (Denmark)

    Hokland, M; Hokland, P; Heron, I;

    1983-01-01

    Mixed lymphocyte reaction (MLR) cultures of human lymphocyte subsets with or without the addition of physiological doses of human alpha interferon (IFN-alpha) were compared with respect to surface marker phenotypes and proliferative capacities of the responder cells. A selective depression on the T...... T4 cells and decreased numbers of T4 cells harvested from IFN MLRs (days 5-6 of culture). In contrast, it was shown that the T8 (cytotoxic/suppressor) subset in MLRs was either not affected or slightly stimulated by the addition of IFN. The depression of the T4 cells by IFN was accompanied......4 (inducer) T-cell subset could be demonstrated as a sequence of events: decreased fluorescence intensity of the T4 inducer cells (day 2 of culture), decreased percentages of T4 cells as demonstrated by cell cytofluorometry (days 3-6 of culture), and decreased 3H-thymidine incorporation of purified...

  8. Specific depletion of mature T lymphocytes from human bone marrow

    DEFF Research Database (Denmark)

    Geisler, C; Møller, J; Plesner, T;

    1989-01-01

    An effective method for specific depletion of mature T lymphocytes from human bone marrow mononuclear cells (BMMC) with preservation of prethymic T cells and natural killer (NK) cells is presented. The BMMC were incubated with F101.01, a monoclonal antibody recognizing an epitope of the T...

  9. Specific expression of GPR56 by human cytotoxic lymphocytes

    NARCIS (Netherlands)

    Y.M. Peng; M.D.B. van de Garde; K.F. Cheng; P.A. Baars; E.B.M. Remmerswaal; R.A.W. van Lier; C.R. Mackay; H.H. Lin; J. Hamann

    2011-01-01

    We here report the existence of a new cluster of adhesion-GPCRs in human immune cells. Analysis of a comprehensive immune cell transcriptome dataset indicated that expression of the closely related receptors, GPR56, GPR97, and GPR114, is associated with single lymphocyte and granulocyte subsets. App

  10. In vitro modeling of the interaction between human epithelial cells and lymphocytes upon influenza infection.

    Science.gov (United States)

    Ilyushina, Natalia A; Wright, Peter F

    2016-09-01

    Influenza viruses are a continuous threat to humans because of their ability to cross species barriers and adapt to new hosts. Data from murine studies, along with limited human data, suggest that CD8(+) cytotoxic T lymphocytes (CTL) that recognize conserved epitopes of structural influenza proteins are the main mediators of influenza virus clearance. Additionally, the fact that many CTLs recognize epitopes shared between different influenza strains offers the potential for broad cross-strain immunity. However, the mechanisms of cellular immunity against influenza viruses are poorly defined in humans, where the CTL response has been hard to measure and interpret. We developed a novel CTL assay that utilizes fully differentiated nasal human epithelial cells taken from volunteers as permissive targets for autologous peripheral blood-derived influenza virus-specific cytotoxic T lymphocytes. This in vitro system of human lymphocyte-epithelial cell co-cultures can be considered as the closest approximation to events in vivo and can be employed for studying the interactions between the pathogen and human host. Modeling of the natural interaction process between the primary cell type that supports the productive replication of influenza and immune cells may allow us to put in perspective CTLs as a correlate of immunity to influenza in humans. PMID:27102577

  11. Human Adaptations: Free divers

    OpenAIRE

    Tournat, Troy Z.

    2014-01-01

    Freediving has been around for thousands of years and was only way to dive until the inventionof oxygen tanks in the 19th century. Around the world, people dove for goods such as pearls, andtoday people freedive for sport. Divers stretch the limit of their body and mind’s capabilitiesthrough psychological adaptations from thermal, respiratory, and cardiovascular responses.Findings conclude that thermal adaptations are a similar process to cold adaptive response. Withthe implementation of wets...

  12. Effect of chloroquine on human lymphocyte proliferation

    DEFF Research Database (Denmark)

    Bygbjerg, Ib Christian; Flachs, H

    1986-01-01

    The effect of chloroquine on human blood mononuclear cells was studied. High concentrations of chloroquine in vitro profoundly suppressed the proliferation of mitogen- and antigen-stimulated cells, as indicated by decreased 14C-thymidine incorporation. Lower concentrations of chloroquine increase...

  13. Production of C-reactive protein by human lymphocytes

    International Nuclear Information System (INIS)

    C-reactive protein (CRP) is a major acute phase serum protein in humans; it is detectable at very high concentrations during infection and tissue trauma. This protein is a pentame composed of five identical, 21,500 MW subunits. CRP is detectable on the surface of approximately 4% of normal peripheral blood lymphocytes (PBL). CRP binds its physiological ligands in a Ca++ dependent manner; removal of Ca++ does not alter the expression of CRP on the lymphocyte surface. Recently, investigators in this laboratory reported substantial inhibition of natural killer cell (NK) activity with anti-CRP antibodies. The following studies were undertaken to determine the origin of surface-CRP (S-CRP) found on normal PBL. Cells were incubated in methionine-free DMEM supplemented with 35S-methionine. Cells were lysed and subjected to immunoprecipitation with anti-CRP and Staphylococcus aureus; immunoprecipitates were analyzed by SDS-PAGE and autoradiography. Data presented here suggested that lymphocytes, in particular, LGL produce small amounts of CRP and express it on their surface. Lymphocytes do not appear to secrete CRP since no CRP could be detected in culture supernatants. In addition, preliminary evidence indicates that peripheral blood monocytes produce no detectable CRP. Present studies utilizing Northern blot analysis are underway in order to detect CRP-mRNA

  14. An Act of Balance Between Adaptive and Maladaptive Immunity in Depression: a Role for T Lymphocytes.

    Science.gov (United States)

    Toben, Catherine; Baune, Bernhard T

    2015-12-01

    Historically the monoaminergic neurotransmitter system, in particular the serotonergic system, was seen as being responsible for the pathophysiology of major depressive disorder (MDD). With the advent of psychoneuroimmunology an important role of the immune system in the interface between the central nervous systems (CNS) and peripheral organ systems has emerged. In addition to the well-characterised neurobiological activities of cytokines, T cell function in the context of depression has been neglected so far. In this review we will investigate the biological roles of T cells in depression. Originally it was thought that the adaptive immune arm including T lymphocytes was excluded from the CNS. It is now clear that peripheral naïve T cells not only carry out continuous surveillance within the brain but also maintain neural plasticity. Furthermore animal studies demonstrate that regulatory T lymphocytes can provide protection against maladaptive behavioural responses associated with depression. Psychogenic stress as a major inducer of depression can lead to transient trafficking of T lymphocytes into the brain stimulating the secretion of certain neurotrophic factors and cytokines. The separate and combined mechanism of CD4 and CD8 T cell activation is likely to determine the response pattern of CNS specific neurokines and neurotrophins. Under chronic stress-induced neuroinflammatory conditions associated with depression, T cell responses may become maladaptive and can be involved in neurodegeneration. Additionally, intracellular adhesion and MHC molecule expression as well as glucocorticoid receptor expression within the brain may play a role in determining T lymphocyte functionality in depression. Taken together, T lymphocyte mechanisms, which confer susceptibility or resilience to MDD, are not yet fully understood. Further insight into the cellular and molecular mechanisms which balance the adaptive and maladaptive roles of T lymphocytes may provide a better

  15. Electrostimulation of rat callus cells and human lymphocytes in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Aro, H.; Eerola, E.; Aho, A.J.; Penttinen, R.

    1984-01-01

    Asymmetrical pulsing low voltage current was supplied via electrodes to cultured rat fracture callus cells and human peripheral blood lymphocytes. The (/sup 3/H)thymidine incorporation of the callus cells and 5-(/sup 125/I)iodo-2'-deoxyuridine incorporation of the lymphocytes were determined. The growth pattern of callus cells (estimated by cellular density) did not respond to electrical stimulation. However, the uptake of (/sup 3/H)thymidine was increased at the early phase of cell proliferation and inhibited at later phases of proliferation. The (/sup 3/H)thymidine uptake of confluent callus cell cultures did not respond to electrical stimulation. Lymphocytes reacted in a similar way; stimulated cells took up more DNA precursor than control cells at the early phase of stimulation. During cell division, induced by the mitogens phytohemagglutinin and Concanavalin-A, the uptake of DNA precursor by stimulated cells was constantly inhibited. The results suggest that electrical stimuli affect the uptake mechanisms of cell membranes. The duality of the effect seems to be dependent on the cell cycle.

  16. Interference of CD95 expression on human lymphocytes.

    Science.gov (United States)

    Petanova, Jitka; Fucikova, Terezie; Bencko, Vladimir

    2002-02-01

    The study presents the exogenous influence of cadmium in comparison with zinc on the apoptosis of human lymphocytes by CD95 expression and its kinetic changes. The salts of both metals were used in final concentrations of 20 microM in cell cultures with whole blood. The duration of cultivation was 18 and 90 hours. The expression of surface antigens was evaluated by flow cytometry with monoclonal antibodies. In cultures of not stimulated cells we found in average 51.54% CD95 positive lymphocytes. The kinetic study of untreated cells showed elevation after 18 hours of cultivation and a very low expression after 90 hours. The CD95 expression on lymphocytes in cell culture with cadmium and zinc was lower after 18 hours of cultivation than in untreated cells. After 90 hours cultivation we found low levels of CD95 expression on cells treated with cadmium and a great individual variability in the number of positive cells upon the influence of zinc.

  17. [Retarded excision of pyrimidine dimers in human unstimulated lymphocytes].

    Science.gov (United States)

    Snopov, S A; Roza, L; de Gruijl, F R

    2006-01-01

    Using immuno-labelling of cyclobutane pyrimidine dimers (CPDs) in nuclei of peripheral lymphocytes after their UVC-irradiation and cultivation, we have found that within the first four hours of cultivation the CPD-specific fluorescent signal from cell nuclei increased. Earlier, a similar increase in binding of antibody specific for pyrimidine (6-4) pyrimidone photoproducts to undenatured DNA isolated from UV-irradiated Chinese hamster ovary cells was reported (Mitchell et al., 1986). Our experiments showed that nucleotide excision repair enzyme might induce such of DNA modification in lymphocyte nuclei that increased specific antibody binding to DNA fragments with lesions. We suggest that enzymatic formation of open structures in DNA predominated qualitatively over dual-incision and excision of these fragments, and resulted in the enhanced exposure of the pyrimidine dimers in nuclei to specific antibodies. The results evidence that nucleotid excision repair in unstimualted human lymphocytes being deficient in dual incision and removal of UV-induced DNA lesions appear to be capable of performing chromatin relaxation and pre-incision uncoiling of DNA fragments with lesions.

  18. Combined cytotoxic effects of ionizing radiation and magnetic field in yeasts and human lymphocytes

    International Nuclear Information System (INIS)

    Full text: The aim of this study was to give evidence about in vitro non-cumulative effects induced in low eukaryotic and mammalian cells by pre-exposure to low frequency (50 Hz) and low amplitude (100-300 μT) magnetic fields, upon subsequent irradiation with doses known to produce high cytotoxic effects. Two types of cells characterized by different radiosensitivity were investigated, namely: i) yeast cells (Saccharomyces cerevisiae X310 D), the parameter measured by cell survival test was the cell viability normalized by the viability in the control, and ii) human peripheral blood lymphocytes: PHA-stimulated whole-blood lymphocyte cultures and unstimulated (G0) separated lymphocyte cultures. As a radiotoxicity parameter for lymphocytes the micronuclei (MN) induction was used: a) MN index, YMN = number of MN / per 1000 binucleated cells; b) cytokinesis block proliferation index (CBPI): CBPI=[binucleated cells]+2x [multinucleated cells]/[total cells] The apoptosis degree of unstimulated (G0) separated lymphocytes was observed by monitoring nuclear morphological changes under double staining with acridine orange and ethidium homodimer. It has been observed that a 50 Hz magnetic field of 100 μT stimulates the radioresistance of S.cerevisiae culture upon subsequent irradiation with a dose of 2.4 kGy (1.2 kGy/h dose rate). On the contrary, when S.cerevisiae cultures were exposed to 200 and 300 μT, under the same conditions, they show an apparent radiosensitivity. In the case of human lymphocytes cultures, the combined exposures show the induction of an adaptive type reaction to G2 irradiation subsequent to short pre-exposures (1h) at 100-300 μT. The effect is better expressed by the proliferation index than by the MN level. The apoptosis degree of lymphocytes after 2 Gy gamma irradiation in G0 is lower when the cultures were pre-exposed at 100μT magnetic field. Pre-exposure to higher inductions, i.e. 300 μT, will no longer protect the cells against gamma

  19. Effect of oral proguanil on human lymphocyte proliferation

    DEFF Research Database (Denmark)

    Bygbjerg, Ib Christian; Flachs, H

    1986-01-01

    In vitro studies have indicated that the antifolates pyrimethamine [4, 6] and cycloguanil (the active metabolite of proguanil) suppress the proliferation of stimulated human lymphocytes; proguanil has no effect [2]. During the early growth phase of the cells, 14C-thymidine (14C-TdR) incorporation...... is increased by pyrimethamine and cycloguanil, reflecting blockage of endogenous TdR synthesis [3]. Proguanil (Paludrine) is increasingly being used for malaria prophylaxis. It is considered the most innocuous of the antimalarials currently employed. Since nothing is known about the effect of oral proguanil...

  20. Serine leucocyte proteinase inhibitor-treated monocyte inhibits human CD4(+) lymphocyte proliferation.

    Science.gov (United States)

    Guerrieri, Diego; Tateosian, Nancy L; Maffía, Paulo C; Reiteri, Romina M; Amiano, Nicolás O; Costa, María J; Villalonga, Ximena; Sanchez, Mercedes L; Estein, Silvia M; Garcia, Verónica E; Sallenave, Jean-Michel; Chuluyan, Héctor E

    2011-08-01

    Serine leucocyte proteinase inhibitor (SLPI) is the main serine proteinase inhibitor produced by epithelial cells and has been shown to be a pleiotropic molecule with anti-inflammatory and microbicidal activities. However, the role of SLPI on the adaptive immune response is not well established. Therefore, we evaluated the effect of SLPI on lymphocyte proliferation and cytokine production. Human peripheral blood mononuclear cells (PBMC) were treated with mitogens plus SLPI and proliferation was assessed by [(3) H]thymidine uptake. The SLPI decreased the lymphocyte proliferation induced by interleukin-2 (IL-2) or OKT3 monoclonal antibodies in a dose-dependent manner. Inhibition was not observed when depleting monocytes from the PBMC and it was restored by adding monocytes and SLPI. SLPI-treated monocyte slightly decreased MHC II and increased CD18 expression, and secreted greater amounts of IL-4, IL-6 and IL-10 in the cell culture supernatants. SLPI-treated monocyte culture supernatant inhibited the CD4(+) lymphocyte proliferation but did not affect the proliferation of CD8(+) cells. Moreover, IL-2 increased T-bet expression and the presence of SLPI significantly decreased it. Finally, SLPI-treated monocyte culture supernatant dramatically decreased interferon-γ but increased IL-4, IL-6 and IL-10 in the presence of IL-2-treated T cells. Our results demonstrate that SLPI target monocytes, which in turn inhibit CD4 lymphocyte proliferation and T helper type 1 cytokine secretion. Overall, these results suggest that SLPI is an alarm protein that modulates not only the innate immune response but also the adaptive immune response. PMID:21574992

  1. Serine leucocyte proteinase inhibitor-treated monocyte inhibits human CD4+ lymphocyte proliferation

    Science.gov (United States)

    Guerrieri, Diego; Tateosian, Nancy L; Maffía, Paulo C; Reiteri, Romina M; Amiano, Nicolás O; Costa, María J; Villalonga, Ximena; Sanchez, Mercedes L; Estein, Silvia M; Garcia, Verónica E; Sallenave, Jean-Michel; Chuluyan, Héctor E

    2011-01-01

    Serine leucocyte proteinase inhibitor (SLPI) is the main serine proteinase inhibitor produced by epithelial cells and has been shown to be a pleiotropic molecule with anti-inflammatory and microbicidal activities. However, the role of SLPI on the adaptive immune response is not well established. Therefore, we evaluated the effect of SLPI on lymphocyte proliferation and cytokine production. Human peripheral blood mononuclear cells (PBMC) were treated with mitogens plus SLPI and proliferation was assessed by [3H]thymidine uptake. The SLPI decreased the lymphocyte proliferation induced by interleukin-2 (IL-2) or OKT3 monoclonal antibodies in a dose-dependent manner. Inhibition was not observed when depleting monocytes from the PBMC and it was restored by adding monocytes and SLPI. SLPI-treated monocyte slightly decreased MHC II and increased CD18 expression, and secreted greater amounts of IL-4, IL-6 and IL-10 in the cell culture supernatants. SLPI-treated monocyte culture supernatant inhibited the CD4+ lymphocyte proliferation but did not affect the proliferation of CD8+ cells. Moreover, IL-2 increased T-bet expression and the presence of SLPI significantly decreased it. Finally, SLPI-treated monocyte culture supernatant dramatically decreased interferon-γ but increased IL-4, IL-6 and IL-10 in the presence of IL-2-treated T cells. Our results demonstrate that SLPI target monocytes, which in turn inhibit CD4 lymphocyte proliferation and T helper type 1 cytokine secretion. Overall, these results suggest that SLPI is an alarm protein that modulates not only the innate immune response but also the adaptive immune response. PMID:21574992

  2. Ultraviolet-induced DNA excision repair in human B and T lymphocytes. 3. Repair in lymphocyte from chronic lymphocytic leukaemia

    International Nuclear Information System (INIS)

    This study examined the capacity of lymphocytes from individuals with chronic lymphocytic leukaemia (CLL) to undertake ultraviolet (u.v.)-induced DNA repair in comparison to control and age-matched purified B and T lymphocytes. The technique was independent of incorporation of radioactive precursor, i.e. by the recovery of normal sedimentation behaviour of nucleoid bodies obtained from these cells by lysis in high salt and non-ionic detergent. Recovery of normal sedimentation was associated with restoration of DNA supercoiling. CLL cells were found to be as sensitive to u.v. and to repair at similar rates as age-matched B controls. They were considerably more sensitive than young B cells and repaired less efficiently. Reasons for previous reported discrepancies in CLL repair were discussed. (author)

  3. Human whole body cold adaptation.

    Science.gov (United States)

    Daanen, Hein A M; Van Marken Lichtenbelt, Wouter D

    2016-01-01

    Reviews on whole body human cold adaptation generally do not distinguish between population studies and dedicated acclimation studies, leading to confusing results. Population studies show that indigenous black Africans have reduced shivering thermogenesis in the cold and poor cold induced vasodilation in fingers and toes compared to Caucasians and Inuit. About 40,000 y after humans left Africa, natives in cold terrestrial areas seems to have developed not only behavioral adaptations, but also physiological adaptations to cold. Dedicated studies show that repeated whole body exposure of individual volunteers, mainly Caucasians, to severe cold results in reduced cold sensation but no major physiological changes. Repeated cold water immersion seems to slightly reduce metabolic heat production, while repeated exposure to milder cold conditions shows some increase in metabolic heat production, in particular non-shivering thermogenesis. In conclusion, human cold adaptation in the form of increased metabolism and insulation seems to have occurred during recent evolution in populations, but cannot be developed during a lifetime in cold conditions as encountered in temperate and arctic regions. Therefore, we mainly depend on our behavioral skills to live in and survive the cold. PMID:27227100

  4. Monoclonal antibodies to antigens on human neutrophils, activated T lymphocytes, and acute leukemia blast cells

    Energy Technology Data Exchange (ETDEWEB)

    Miterev, G.Yu.; Burova, G.F.; Puzhitskaya, M.S.; Danilevich, S.V.; Bulycheva, T.I.

    1987-11-01

    The authors describe the production of two mouse hybridomas secreting monoclonal antibodies to antigenic determinants of the surface membranes of human neutrophils, activated T lymphocytes, and acute leukemic blast cells. The degree of lymphocyte stimulation was estimated from incorporation of /sup 3/H-thymidine with parallel microculture. Monoclonal antibodies of supernatants of hybridoma cultures shown here reacted in both immunofluorescence test and cytotoxicity test with surface membrane antigens on the majority of neutrophils and PHA-activated peripheral blood lymphocytes from healthy subjects, but did not give positive reactions with unactivated lymphocytes, adherent monocytes, erythrocytes, and alloantigen-stimulated lymphocytes.

  5. Effects of microgravity and cosmic radiations on human T lymphocytes

    Directory of Open Access Journals (Sweden)

    P. Pippia

    2011-01-01

    Full Text Available In space living organisms, including cells, are affected by two new environmental conditions: microgravity and cosmic radiations. Several experiments in dedicated space missions and in simulated microgravity have shown that low gravity causes a dramatic depression of the mitogenic in vitro activation of T lymphocytes. The goal of this reserch was to determine in space (on board the International Space Station the ability of adherent monocytes to migrate, as well as to interact with T-cells. A reduced motility of the J-111 cells and changes in the structures of actin, tubulin and vinculin were observed. Moreover, we demonstrated that LFA-I/ICAM-I interactions occur in space and are dependent on activation time but show differences in number, arrangement and fluorescence intensity, depending on time and experimental conditions. In order to evaluate the effects of cosmic radiations on the gene expression in human T lymphocytes we exposed these cells to high quote cosmic radiation during two stratospheric balloon trans-mediterranean flights (BIRBA missions. The gene expression was analized by cDNA microarray hybridization technology. Activated T cells react to the ionizing stress by activating genes involved in cell cycle check-point, oxidative stress response, heat shock proteins production or by repressing denes involved in antigen recognition.

  6. Radiation-induced chromosome damage in human lymphocytes

    International Nuclear Information System (INIS)

    Analysis for chromosome aberrations in human peripheral blood lymphocytes has been developed as an indicator of dose from ionising radiation. An outline is given of the mechanism of production of aberrations, the technique for their analysis and the dose-effect relationships for various types of radiation. During the past ten years the National Radiological Protection Board has developed a service for the UK in which estimates of dose from chromosomes aberration analysis are made on people known or suspected of being accidentally over-exposed. This service can provide estimates where no physical dosemeter was worn and is frequently able to resolve anomalous or disputed data from routine film badges. Several problems in the interpretation of chromosome aberration yields are reviewed. These include the effects of partial body irradiation and the response to variations in dose rate and the intermittent nature of some exposures. The dosimetry service is supported by a research programme which includes surveys of groups of patients irradiated for medical purposes. Two surveys are described. In the first, lymphocyte aberrations were examined in rheumatoid arthritis patients receiving intra-articular injections of colloidal radiogold or radioyttrium. A proportion of the nuclide leaked from the joint into the regional lymphatic system. In the second survey a comparison was made between the cytogenetic and physical estimates of whole body dose in patients receiving iodine 131 for thyroid carcinoma. (author)

  7. Carbamate Pesticide-Induced Apoptosis in Human T Lymphocytes

    Directory of Open Access Journals (Sweden)

    Qing Li

    2015-04-01

    Full Text Available We previously found that carbamate pesticides induced significant apoptosis in human natural killer cells. To investigate whether carbamate pesticides also induce apoptosis in human T lymphocytes, in the present study Jurkat human T cells were treated in vitro with thiram, maneb, carbaryl or ziram. Apoptosis was determined by FITC-Annexin-V/PI staining. To explore the mechanism of apoptosis, intracellular levels of active caspase 3 and mitochondrial cytochrome-c release were determined by flow cytometry. We found that thiram, ziram, maneb and carbaryl also induced apoptosis in a time- and dose-dependent manner in the human T cells. However, the strength of the apoptosis-inducing effect differed among the pesticides, with the: thiram > ziram > maneb > carbaryl. Moreover, thiram significantly increased the intracellular level of active caspase 3 and caspase inhibitors significantly inhibited apoptosis. Thiram also significantly caused mitochondrial cytochrome-c release. These findings indicate that carbamate pesticides can induce apoptosis in human T cells, and the apoptosis is mediated by the activation of caspases and the release of mitochondrial cytochrome-c.

  8. Quiescent human lymphocytes do not contain DNA strand breaks detectable by alkaline elution

    International Nuclear Information System (INIS)

    On the basis of qualitative assays, quiescent lymphocytes have previously been reported to have numerous DNA strand breaks, which are thought to be repaired after mitogenic stimulation by a process associated with poly(ADP-ribosyl)ation. Using alkaline elution, a very sensitive assay for quantifying DNA single-strand breakage, the authors found no evidence for a high frequency of DNA strand breaks in unstimulated human peripheral blood lymphocytes. No differences in elution profiles were observed between unstimulated lymphocytes and lymphocytes 4 or 48 h after addition of the mitogen phytohemagglutinin (PHA). In contrast to reported studies of mouse splenic lymphocytes, they found that human lymphocytes were able to replicate and divide in the presence of the ADP-ribosylation inhibitor. Human lymphocytes were also capable of proliferating n nicotinamide-free medium, with or without 3AB, indicating that ADP-ribosylation is not a requirement for lymphocyte differentiation. They therefore consider it unlikely that peripheral human lymphocytes contain significant numbers of strand breaks that play any role in their stimulation of differentiation in response to PHA

  9. Effect of antimalarial drugs on stimulation and interleukin 2 production of human lymphocytes

    DEFF Research Database (Denmark)

    Bygbjerg, I C; Svenson, M; Theander, T G;

    1987-01-01

    Effect of pyrimethamine, an antimalarial antifolate, and of mefloquine, chloroquine, and quinine, which belong to the quinoline group of antimalarials, on proliferation and interleukin 2 (IL-2) production of human lymphocytes was studied in vitro. Pyrimethamine at concentrations above therapeutic...... levels suppressed the lymphocytes' proliferation, but not their IL-2 production. All three quinolines suppressed the proliferation of lymphocytes, but not equally, with mefloquine having the strongest effect. Quinine suppressed the growth at therapeutic concentrations. The IL-2 production was suppressed...

  10. Binding of 125I-human growth hormone to specific receptors in human cultured lymphocytes

    International Nuclear Information System (INIS)

    The interaction of human growth hormone with human lymphocytes from an established culture (IM-9) was studied using 125I- human growth hormone. The binding of 125I-human growth hormone was rapid; with human growth hormone at 0.1 nM a steady state was observed in 90 min at 300. Bound labeled human growth hormone was dissociated rapidly by addition of excess unlabeled human growth hormone. Binding of 125I-human growth hormone to cultured lymphocytes was relatively insensitive to alterations in the pH and in the concentrations of Ca2+, Mg2+, EDTA. At 800 there was very little degradation of labeled human growth hormone or of the specific receptor sites. Tryptic digestion destroyed the capacity of cells to bind human growth hormone. The IM-9 cells bound all human growth hormone preparations but not unrelated hormones or nonprimate growth hormones. The binding of 125I-human growth hormone was inhibited 10 to 14 percent with 1 to 2 ng per ml of unlabeled human growth hormone and 50 percent with 30 to 40 ng per ml, well within the range of hormone concentrations in vivo. Analysis of steady state data revealed a single order of binding sites with an affinity constant of 1.3 x 109 M-1 and about 4000 binding sites per cell. Numerous human growth hormone preparations were assayed by use of this receptor system as well as by immunoassay and by bioassay in vivo. The po

  11. Effects of incense smoke on human lymphocyte DNA.

    Science.gov (United States)

    Szeto, Yim Tong; Sok Wa Leong, Kosca; Keong Lam, Kason; Min Min Hong, Cynthia; Kai Mui Lee, Daphne; Teng Fun Chan, Yui; Benzie, Iris F F

    2009-01-01

    Incense burning is common in Southeast Asia, where it is a traditional and ceremonial practice in deity worship and paying respect to ancestors. However, incense emissions are an important source of indoor air pollution in Asia, and may induce health problems to those exposed. In this in vitro study the effects of incense emissions on human DNA were investigated using the comet assay. Particulates in smoke from six kinds of incense were trapped in saline or ethanol and human lymphocytes were exposed under controlled conditions. Results showed that DNA damage, including strand breaks, was induced by both aqueous and ethanolic extracts of two samples. The ethanolic extract of one sample induced DNA damage, while no significant DNA damage was found in the remaining three samples. The mechanisms underlying DNA damage induced by incense emissions were also investigated. Catalase (CAT), sodium azide, and superoxide dismutase (SOD) were co-incubated with extract, which exerted significant DNA damaging effects. Results showed that CAT with or without SOD diminished DNA damage, whereas sodium azide did not seem able to reduce DNA damage. Data indicate there are potential adverse health effects of such exposure, particularly for temple workers.

  12. Proteolytically modified human beta 2-microglobulin augments the specific cytotoxic activity in murine mixed lymphocyte culture

    DEFF Research Database (Denmark)

    Nissen, Mogens Holst; Claësson, M H

    1987-01-01

    (M-beta 2-m) bind to murine lymphocytes expressing H-2 class I antigens; M-beta 2-m, when added at day 0 and 1 of culture in nanomolar concentrations to a one-way murine allogeneic mixed lymphocyte culture (MLC) augments the generation of specific cytotoxic T lymphocytes; M-beta 2-m increases...... the endogenous production of interleukin 2 in the MLC culture; monoclonal antibody which reacts with both the native beta 2-m and M-beta 2-m molecule blocks the augmentation of cytotoxic T lymphocyte production induced by M-beta 2-m; murine as well as human MLC responder cells can proteolytically modify native...

  13. Viral Engineering of Chimeric Antigen Receptor Expression on Murine and Human T Lymphocytes.

    Science.gov (United States)

    Hammill, Joanne A; Afsahi, Arya; Bramson, Jonathan L; Helsen, Christopher W

    2016-01-01

    The adoptive transfer of a bolus of tumor-specific T lymphocytes into cancer patients is a promising therapeutic strategy. In one approach, tumor specificity is conferred upon T cells via engineering expression of exogenous receptors, such as chimeric antigen receptors (CARs). Here, we describe the generation and production of both murine and human CAR-engineered T lymphocytes using retroviruses. PMID:27581020

  14. Carotenoids located in human lymphocyte subpopulations and natural killer cells by Raman microspectroscopy

    NARCIS (Netherlands)

    Puppels, G.J.; Garritsen, H.S.P.; Kummer, J.A.; Greve, Jan

    1993-01-01

    The presence and subcellular location of carotenoids in human lymphocyte sub-populations (CD4+, CD8+, T-cell receptor-γδ+, and CD19+ ) and natural killer cells (CD16+ ) were studied by means of Raman microspectroscopy. In CD4+ lymphocytes a high concentration (10-3M) of carotenoids was found in the

  15. 5-Lipoxygenase-dependent apoptosis of human lymphocytes in the International Space Station: data from the ROALD experiment.

    Science.gov (United States)

    Battista, Natalia; Meloni, Maria A; Bari, Monica; Mastrangelo, Nicolina; Galleri, Grazia; Rapino, Cinzia; Dainese, Enrico; Agrò, Alessandro Finazzi; Pippia, Proto; Maccarrone, Mauro

    2012-05-01

    The functional adaptation of the immune system to the surrounding environment is also a fundamental issue in space. It has been suggested that a decreased number of lymphocytes might be a cause of immunosuppression, possibly due to the induction of apoptosis. Early activation of 5-lipoxygenase (5-LOX) might play a central role in the initiation of the apoptotic program. The goal of the role of apoptosis in lymphocyte depression (ROALD) experiment, flown on the International Space Station as part of the BIO-4 mission of the European Space Agency, was to ascertain the induction of apoptosis in human lymphocytes under authentic microgravity, and to elucidate the possible involvement of 5-LOX. Our results demonstrate that exposure of human lymphocytes to microgravity for 48 h onboard the ISS remarkably increased apoptotic hallmarks such as DNA fragmentation (∼3-fold compared to ground-based controls) and cleaved-poly (ADP-ribose) polymerase (PARP) protein expression (∼3-fold), as well as mRNA levels of apoptosis-related markers such as p53 (∼3-fold) and calpain (∼4-fold); these changes were paralleled by an early increase of 5-LOX activity (∼2-fold). Our findings provide a molecular background for the immune dysfunction observed in astronauts during space missions, and reveal potential new markers to monitor health status of ISS crew members.

  16. Chromosome aberrations induced in human lymphocytes by neutron irradiation

    International Nuclear Information System (INIS)

    In vitro dose-response curves of unstable chromosome aberrations in human lymphocytes have been obtained for neutron spectra of mean energies 0.7, 0.9, 7.6 and 14.7 MeV. The aberration yields have been fitted to the quadratic function Y = αD + βD2, which is consistent with the single-track and two-track model of aberration formation. However with high-LET radiation, the linear component of yield, corresponding to damage caused by single tracks, predominates, and this term becomes more dominant with increasing LET, so that for fission spectrum neutrons the relationship is linear, Y = αD. At low doses, such as those received by radiation workers, limiting r.b.e. values between 13 and 47 were obtained relative to 60Co γ-radiation. At higher doses, as used in radiotherapy, the values were much lower; ranging from 2.7 to 8 at 200 rad of equivalent γ-radiation. Both sets of r.b.e. values correlated well with track-averaged LET but not with dose-averaged LET. When the numbers of cells without aberrations were plotted against radiation dose, curves were obtained which are similar in shape to those for conventional cell-survival experiments with comparable neutron spectra. The D0 values obtained in the present study are close to those from other cell systems. (author)

  17. DMPD: Induction of proliferation and cytokine production in human T lymphocytes bylipopolysaccharide (LPS). [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 11090938 Induction of proliferation and cytokine production in human T lymphocytes ... (.png) (.svg) (.html) (.csml) Show Induction of proliferation and cytokine production in human T lymphocyte...s bylipopolysaccharide (LPS). PubmedID 11090938 Title Induction of proliferation and cytokine production

  18. The Genotoxicity of Sodium Arsenite in Human Lymphocyte Culture

    International Nuclear Information System (INIS)

    Sodium arsenite was tested for its clastogenic effect alone and on isolated lymphocyte culture. The results showed a significant difference in the yield of chromosome aberrations induced with respect to the culture time 48 h. Whole blood culture showed significant increase in gaps and breaks whereas isolated lymphocyte culture showed significant inhibition of cell cycle and 75% of the lymphocytes were in their first cell cycle at 72 hr. Arsenite showed co-mutagenicity with different doses of x-ray delivered immediately or few hours after treatment of the culture with S A. The results suggest that S A is also mutagenic at the dose level used and provide support for the indispensability of whole blood culture for evaluation of the in vivo effect of any suspected mustagen using isolated lymphocytes appear to have problems leading to extensive cell cycle delay

  19. Genotoxicity of food preservative sodium sorbate in human lymphocytes in vitro.

    Science.gov (United States)

    Mamur, Sevcan; Yüzbaşıoğlu, Deniz; Unal, Fatma; Aksoy, Hüseyin

    2012-10-01

    The genotoxic effects of antimicrobial food additive sodium sorbate (SS) was assessed by using chromosome aberrations (CAs), sister-chromatid exchanges (SCEs), and micronucleus (MN) in cultured human lymphocytes and comet assay in isolated human lymphocytes. Lymphocytes were treated with four concentrations (100, 200, 400 and 800 μg/ml) of SS as well as a negative (sterile distilled water) and a positive control (Mitomycin-C: MMC for cultured lymphocytes and H(2)O(2) for isolated lymphocytes). The result of this study indicated that SS increased the frequency of CAs at both 24 and 48 h period compared to control. When gaps were included, this increase was significant at 200, 400 and 800 μg/ml concentrations at 24 h and, at all concentrations at 48 h treatment time. When gaps were excluded, this increase was significant at only 800 μg/ml concentration at both 24 and 48 h treatments. In addition, SS increased SCEs/cell and MN frequency at 400 and 800 μg/ml concentrations at both 24 and 48 h compared to negative control. Furthermore, this additive caused DNA damage at all concentrations in isolated human lymphocytes after 1 h in vitro exposure. The present results show that SS is genotoxic to the human peripheral blood lymphocytes in vitro at the highest concentrations.

  20. DNA damage in human lymphocytes due to synergistic interaction between ionizing radiation and pesticide

    International Nuclear Information System (INIS)

    Biological risks may arise from the possibility of the synergistic interaction between harmful factors such as ionizing radiation and pesticide. The effect of pesticide on radiation-induced DNA damage in human in human blood lymphocytes was evaluated by the single cell gel electrophoresis (SCGE) assay. The lymphocytes, with or without pretreatment of the pesticide, were exposed to 2.0 Gy of gamma ray. Significantly increased tail moment, which was a marker of DNA strand breaks in SCGE assay, showed an excellent dose-response relationship. The present study confirms that the pesticide has the cytotoxic effect on lymphocytes and that it interacts synergistically with ionizing radiationon DNA damage, as well

  1. Modulation of interleukin 2 receptor expression on normal human lymphocytes by thymic hormones.

    OpenAIRE

    Sztein, M B; Serrate, S A; Goldstein, A. L.

    1986-01-01

    The expression of interleukin 2 receptors (IL-2R) is a critical step leading to normal lymphocyte proliferation. Since thymosin fraction 5 (TF5), a thymic hormone preparation, enhances lymphoproliferative responses of human cells, we examined the effects of TF5 on the expression of IL-2R on mitogen-stimulated human lymphocytes. TF5 significantly increased the percentage and antigen density of cells expressing IL-2R after stimulation with an optimal concentration of phytohemagglutinin (PHA) wh...

  2. Signaling in Human and Murine Lymphocytes in Microgravity: Parallels and Contrasts

    Science.gov (United States)

    Neal, Pellis; Alamelu, Sundaresan; Kulkarni, A. D.; Yamauchi, K.

    2006-01-01

    Immune function in space undergoes dramatic changes, some of which are detrimental to lymphocyte function. These changes may lead to significant immune suppression. Studies with human lymphocytes both in space flight and with ground-based models (NASA in vitro ground-based microgravity analog) indicate that T cell activation is inhibited in microgravity. Other lymphocyte functions, such as locomotion, are also inhibited. There is about an 80 percent homology in the immune response of mice to that of humans. A murine model was investigated because of its ability to parallel some microgravity using hind limb suspension. In in vivo antiorthostatically (AOS)-suspended mice, T cell activation is greatly suppressed, with the majority of activation related cytokines being inhibited. PHA activation in lymphocytes derived from AOS mice (in vivo ground-based microgravity analog) is also suppressed. Calcium ionophore studies in human lymphocytes exposed to modeled microgravity indicate that the calcium pathways are probably unaffected in microgravity. IP3 (inositol triphosphate) receptor expression in both human and mouse lymphocytes cultured in modeled microgravity indicate no suppression of calcium signaling. In the human system, microgravity seems to inhibit signaling cascades either at the level of, or up-stream of, Protein Kinase C (PKC). In particular, a membrane event, such as phospholipase C gamma 1 activity in human lymphocytes is affected, with its direct upstream effector, LAT, being deficiently expressed. In the mouse pathway, LAT is undiminished while another critical intermediate, SLP-76, is diminished significantly. This study identifies critical stages in the human and mouse immune systems and in lymphocytes as a function of microgravity.

  3. Lack of permissivity of human monoclonal CD4+ lymphocytes to HIV.

    Science.gov (United States)

    Chapel, A; Bourges, J F; Bensussan, A; d'Auriol, L; Vilmer, E; Dormont, D

    1990-01-01

    Although knowledge has accumulated about GP110-CD4 interaction, viral penetration into human CD4+ lymphocytes remains unclear, in spite of the fact that all studies on HIV infection were performed on cell-transformed lineages, or on human polyclonal CD4+ cells. In order to investigate this viral entrance into susceptible cells, we studied the permissivity of 13 human monoclonal CD4+ lymphocytes by means of reverse transcriptase (RT) assay and immunocapture. We demonstrated a differential susceptibility to HIV of these CD4+ clones. In a second experiment, HIV infection was studied: (1) sequentially by RT assay and P24 immunocapture on several clones; (2) by cocultivation of infected clones with umbilical cord lymphocytes. These experiments suggested existence of permissive and "nonpermissive" CD4+ monoclonal lymphocytes. Slot blot, then PCR, revealed that proviral DNA sequences were detectable in all clones, but were present at lower levels in nonpermissive clones.

  4. Sister chromatid exchange in human lymphocytes induced by propoxur following plant activation by Vicia faba.

    Science.gov (United States)

    Gómez-Arroyo, S; Calderón-Segura, M E; Villalobos-Pietrini, R

    1995-01-01

    Because the carbamate insecticide propoxur induced sister chromatid exchanges (SCE) in Vicia faba but was ineffective in producing SCE in lymphocytes in culture, it was hardly suspected that plant metabolism was involved. Experiments were conducted in which metabolic activation was afforded by Vicia faba roots, and SCE in human lymphocytes in vitro was used to assess cytogenetic damage. Several concentrations of propoxur (250, 500, 1,000, 1,500, and 2,000 ppm) were applied for 4 hr to the roots of Vicia faba. Extracts prepared from these treatments were added to the lymphocyte cultures and a significant increase of SCE frequencies with a concentration-response relationship could be detected. The lymphocyte proliferation kinetics and the proliferation rate index (PRI) were not affected (except in the highest concentration, of 2,000 ppm). This general behavior was in agreement with the presence of an enzymatic system (S10 fraction) in Vicia roots capable of metabolizing or activating the propoxur. With 2,000 ppm, cell necrosis was produced in Vicia; therefore, this extract did not induce SCE in lymphocytes. However, lymphocyte proliferation kinetics were delayed and PRI was significantly decreased. Ethanol, a promutagen activated by this plant, was applied directly to the lymphocyte cultures as a positive control, and the response was negative. On the other hand, the extracts of roots treated with ethanol increased the SCE to more than twice that of the negative control, but the lymphocyte proliferation kinetics and PRI were not affected.

  5. Divergence of human and nonhuman primate lymphocyte responses to bacterial superantigens.

    Science.gov (United States)

    Bavari, S; Hunt, R E; Ulrich, R G

    1995-09-01

    We compared T cell responses of human, rhesus monkey (Macaca mulatta), and chimpanzee (Pan troglodytes) to four bacterial superantigens. When lymphocytes were cultured in media supplemented with species-specific sera, chimpanzee T cells were stimulated by lower doses of staphylococcal enterotoxin (SE) A and toxic shock syndrome toxin 1 (TSST1) than were human T cells, while chimpanzee responses to SEB and SEC1 were nearly equivalent to the human response. Interestingly, rhesus lymphocytes responded to 10,000 times lower amounts of SEA, SEB, and SEC1 and to 100 times lower concentrations of TSST1 than human cells. The greater sensitivity of rhesus T cells to these toxins was not a result of differences in class II binding affinities and was only partly attributable to the presence of anti-SE and TSST1 antibodies in human serum. These results suggest that rhesus T lymphocytes are more sensitive toward these bacterial superantigens than human T cells. PMID:7554446

  6. A comparison of chromosomal aberrations induced by in vivo radiotherapy in human sperm and lymphocytes

    International Nuclear Information System (INIS)

    Chromosomal aberrations in human sperm and lymphocytes were compared before and after in vivo radiation treatment of 13 cancer patients. The times of analyses after radiotherapy (RT) were 1, 3, 12, 24, 36, 48 and 60 months. The median total radiation dose was 30 Gy and the testicular dose varied from 0.4 to 5.0 Gy. Human sperm chromosome complements were analysed after fusion with golden hamster eggs. There were no abnormalities in sperm or lymphocytes before RT. Following RT there was an increase in the frequency of numerical and structural chromosomal abnormalities in both lymphocytes and sperm. For structural abnormalities there were more rejoined lesions (dicentrics, rings) in lymphocytes and more unrejoined lesions (chromosome breaks, fragments) in sperm. It appears that the frequency of lymphocyte chromosomal abnormalities had an initial marked increase after RT followed by a gradual decrease with time whereas the frequency of sperm chromosomal abnormalities was elevated when sperm production recovered and remained elevated from 24 to 60 mo. post-RT. This difference in the effect of time makes it very difficult to compare abnormality rates in lymphocytes and sperm and to use analysis of induced damage in somatic cells as surrogates for germ cells since the ratio between sperm and lymphocytes varied from 1:1 (at 24 mo. post-RT) to 5:1 (at 60 mo. post-RT). (author). 14 refs.; 2 figs.; 5 tabs

  7. Radiation-induced apoptosis in human lymphocytes: Potential as a biological dosimeter

    International Nuclear Information System (INIS)

    We have tested the possibility of using apoptosis (programmed cell death) in human peripheral blood lymphocytes as a short-term biological dosimeter. Lymphocytes isolated from whole blood were irradiated in culture with 250 kVp x-rays or 60Co gamma rays. Two assays were used to measure apoptosis in lymphocytes after irradiation: in situ terminal deoxynucleotidyl transferase assay and fluorescence analysis of DNA unwinding assay. Similar qualitative and quantitative results were produced by the assays, supporting the notion that the fluorescence analysis of DNA unwinding assay measured DNA fragmentation associated with apoptosis. Induction of apoptosis in lymphocytes irradiated in vitro was proportional to dose and could be detected following exposures as low as 0.05 Gy. Lymphocytes irradiated in vitro was proportional to dose and could be detected following exposures as low as 0.05 Gy. Lymphocytes from individual donors had reproducible dose responses. There was, however, variation between donors. X-ray and gamma-ray exposures induced similar levels of apoptosis at similar doses. The induction kinetics of apoptosis in vitro indicate a maximum is reached about 72 h after irradiation. In conclusion, the in vitro experimental evidence indicates that radiation-induced apoptosis in human lymphocytes has the kinetics, sensitivity, and reproductibility to be a potential biological dosimeter. 29 refs., 5 figs

  8. Effect of thapsigargin on cytoplasmic Ca2+ and proliferation of human lymphocytes in relation to AIDS

    DEFF Research Database (Denmark)

    Scharff, O; Foder, B; Thastrup, Ole;

    1988-01-01

    The tumor-promoting sesquiterpene lactone, thapsigargin, induced a dose-dependent increase of the cytoplasmic Ca2+ concentration ([ Ca2+]i) in human lymphocytes from a resting level between 100 and 150 nM up to about 1 microM. Half-maximum response was found at about 1 nM of thapsigargin, full re...... on lymphocyte proliferation by increasing [Ca2+]i, and that the general defect of AIDS lymphocytes, rather than being ascribed to the initiating signal systems, is associated with later events related to DNA synthesis and proliferation....

  9. Activated T lymphocytes disappear from circulation during endotoxemia in humans

    DEFF Research Database (Denmark)

    Suarez Krabbe, Karen; Kemp, Helle Bruunsgaard; Qvist, Jesper;

    2002-01-01

    disappearance were characterized by an activated phenotype (CD45RA(-) CD45RO(+)) as well as a phenotype linked to apoptosis (CD95(+) CD28(-)). In conclusion, endotoxin-induced lymphopenia reflects the disappearance from the circulation of activated lymphocytes prone to undergo apoptosis....

  10. DNA double-strand break rejoining in radioadapted human lymphocytes: evaluation by neutral comet assay and pulse-field gel electrophoresis

    International Nuclear Information System (INIS)

    Adaptive response (AR), an enhanced resistance to a high dose of ionising radiation acquired after pretreatment with a very low dose, was estimated in normal human lymphocytes. The question posed was whether the extent of radioadaptation, assessed by micronucleus test, would be related to the rate of DNA double-strand break (DSB) rejoining. Phytohemagglutinin-stimulated G1-lymphocytes from 5 healthy male volunteers were pre-treated (or not) with an adaptive (5 cGy) dose of X-rays, followed by a higher (5 or 10 Gy) challenge dose after 20-22 h. DSB rejoining after the challenge dose was monitored with the use of two methods: neutral comet assay, modified to reduce the contribution of singlestrand breaks (SSBs) and thermolabile sites, and pulse-field gel electrophoresis (PFGE), specific for DSBs. At the level of micronuclei, an AR was observed in lymphocytes of 3 of 5 donors. Up to 60 min, comet assay showed no statistically significant differences in DNA break rejoining between adapted and non-adapted lymphocytes, independently of AR appearance. PFGE gave similar results, although in three donors it revealed secondary increases in DSBs levels at 30 min and/or 60 min post-irradiation in the adapted vs. the non-adapted samples. Failure to demonstrate changes in DSBs rejoining rate in the adapted lymphocytes could be due to diversity of AR intensity/timing at the level of DNA repair in not fully homogenous cell populations. Also, '' rare '' DNA cuts characteristic of early apoptosis/necrosis could overlap the process of DNA break rejoining. (authors)

  11. In vitro protection of human lymphocytes from toxic effects of chlorpyrifos by selenium-enriched medicines

    OpenAIRE

    Navaei-Nigjeh, Mona; Asadi, Hamidreza; Baeeri, Maryam; Pedram, Sahar; Rezvanfar, Mohammad Amin; Mohammadirad, Azadeh; Abdollahi, Mohammad

    2015-01-01

    Objective(s): Chlorpyrifos (CP) is a broad-spectrum organophosphorus pesticide used extensively in agricultural and domestic pest control, accounting for 50% of the global insecticidal use. In the present study, protective effects of two selenium-enriched strong antioxidative medicines IMOD and Angipars were examined in human lymphocytes treated with CP in vitro. Materials and Methods: Isolated lymphocytes were exposed to 12 µg/ml CP either alone or in combination with effective doses (ED50) ...

  12. Response of human lymphocytes to PHA and tumour-associated antigens as detected by fluorescence polarization.

    OpenAIRE

    Balding, P.; Light, P A; Preece, A. W.

    1980-01-01

    Fluorescence polarization measurement during the progress of fluorochromasia has been used to study the response of human lymphocytes to phytohaemagglutinin (PHA) and to tumour-associated antigens, as a basis for the detection of malignant disease. Polarization (P) values of both stimulated and unstimulated lymphocytes decreased with increasing intracellular fluorescence intensity, and with the duration of the fluorochromatic reaction. When these effects were taken into account, there was no ...

  13. Mitogenic responses of normal human lymphocytes incubated with sera from radium workers

    International Nuclear Information System (INIS)

    Sera from radium workers were incubated with normal human lymphocytes and compared with sera from normal age-matched controls for its effect on lymphocyte stimulation with different mitogens. The results obtained with sera from the radium workers with high residual body burdens (>0.1 μCi 226Ra) were shown to inhibit stimulation following treatment with conconavalin A (Con A) but not with phytohemagglutinin (PHA) nor pokeweed mitogen

  14. Surface redistribution of 125I-insulin in cultured human lymphocytes

    OpenAIRE

    1981-01-01

    The cultured human lymphocyte (IM-9) binds 125I-insulin by a receptor- mediated process; the receptor, in turn, is regulated by the ligand. In the present study we have examined quantitatively the morphologic events involved in 125I-insulin interaction with the surface of the lymphocyte. At 2 min of incubation of 15 degrees or 37 degrees C, the ligand localizes preferentially at the villous surface of the cell, whereas with longer periods of incubation, the ligand distributes indistinguishabl...

  15. Desensitization oft lymphocyte function by CXCR3 ligands in human hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Yu-Qing Liu; Ronnie T. Poon; Jeremy Hughes; Qin-Yu Li; Wan-Ching Yu; Sheung-Tat Fan

    2005-01-01

    AIM: Despite the presence of lymphocyte infiltration, human hepatocellular carcinoma (HCC) is typically a rapidly progressive disease. The mechanism of regulation of lymphocyte migration is poorly understood. In this study,we investigated various factors regulating T cell migration in HCC patients. We examined serum CXC chemokine levels in HCC patients and demonstrated the production of CXC chemokines by HCC cell lines. We determined the effect of both HCC patient serum and tumor cell conditioned supernatant upon lymphocyte expression of chemokine receptor CXCR3 as well as lymphocyte migration. Lastly,we examined the chemotactic responses of lymphocytes derived from HCC patients.METHODS: The serum chemokines IP-10 (CXCL10) and Mig (CXCL9) levels were measured by cytometric bead array (CBA) and the tumor tissue IP-10 concentration was measured by ELISA. The surface expression of CXCR3 on lymphocytes was determined by flow cytometry. The migratory function of lymphocytes to the corresponding chemokines was assessed using an in vitro chemotactic assay. Phosphorylation of extracellular signal-regulated kinase (ERK) was determined by Western blot analysis.RESULTS: Increased levels of IP-10 and Mig were detected in HCC patient serum and culture supernatants of HCC cell lines. The IP-10 concentration in the tumor was significantly higher than that in the non-involved adjacent liver tissues.HCC cell lines secreted functional chemokines that induced a CXCR3-specific chemotactic response of lymphocytes.Furthermore, tumor-cell-derived chemokines induced initial rapid phosphorylation of lymphocyte ERK followed by later inhibition of ERK phosphorylation. The culture of normal lymphocytes with HCC cell line supernatants or medium containing serum from HCC patients resulted in a significant reduction in the proportion of lymphocytes exhibiting surface expression of CXCR3. The reduction in T cell expression of CXCR3 resulted in reduced migration toward the ligand IP-10, and both

  16. [239Pu and chromosomal aberrations in human peripheral blood lymphocytes].

    Science.gov (United States)

    Okladnikova, N D; Osovets, S V; Kudriavtseva, T I

    2009-01-01

    The genome status in somatic cells was assessed using the chromosomal aberration (CA) test in peripheral blood lymphocytes from 194 plutonium workers exposed to occupational radiation mainly from low-transportable compounds of airborne 230Pu. Pu body burden at the time of cytogenetic study varied from values close to the method sensitivity to values multiply exceeding the permissible level. Standard (routine) methods of peripheral blood lymphocytes cultivation were applied. Chromatid- and chromosomal-type structural changes were estimated. Aberrations were estimated per 100 examined metaphase cells. The quantitative relationship between the CA frequency and Pu body burden and the absorbed dose to the lung was found. Mathematical processing of results was carried out based on the phenomenological model. The results were shown as theoretical and experimental curves. The threshold of the CA yield was 0.43 +/- 0.03 kBq (Pu body burden) and 6.12 +/- 1.20 cGy (absorbed dose to the lung).

  17. Antibacterial activity of neem nanoemulsion and its toxicity assessment on human lymphocytes in vitro

    Directory of Open Access Journals (Sweden)

    Jerobin J

    2015-10-01

    Full Text Available Jayakumar Jerobin, Pooja Makwana, RS Suresh Kumar, Rajiv Sundaramoorthy, Amitava Mukherjee, Natarajan Chandrasekaran Centre for Nanobiotechnology, VIT University, Vellore, Tamil Nadu, India Abstract: Neem (Azadirachta indica is recognized as a medicinal plant well known for its antibacterial, antimalarial, antiviral, and antifungal properties. Neem nanoemulsion (NE (O/W is formulated using neem oil, Tween 20, and water by high-energy ultrasonication. The formulated neem NE showed antibacterial activity against the bacterial pathogen Vibrio vulnificus by disrupting the integrity of the bacterial cell membrane. Despite the use of neem NE in various biomedical applications, the toxicity studies on human cells are still lacking. The neem NE showed a decrease in cellular viability in human lymphocytes after 24 hours of exposure. The neem NE at lower concentration (0.7–1 mg/mL is found to be nontoxic while it is toxic at higher concentrations (1.2–2 mg/mL. The oxidative stress induced by the neem NE is evidenced by the depletion of catalase, SOD, and GSH levels in human lymphocytes. Neem NE showed a significant increase in DNA damage when compared to control in human lymphocytes (P<0.05. The NE is an effective antibacterial agent against the bacterial pathogen V. vulnificus, and it was found to be nontoxic at lower concentrations to human lymphocytes. Keywords: neem, nanoemulsion, antibacterial, lymphocytes, cytotoxicity, genotoxicity

  18. Human cord blood lymphocytes. Ultrastructural and immunologic surface marker characteristics: a comparison with B- and T-cell lymphomas

    Energy Technology Data Exchange (ETDEWEB)

    Hamburg, A.; Brynes, R.K.; Reese, C.; Golomb, H.M.

    1976-01-01

    The ultrastructural and surface marker characteristics of human cord blood lymphocytes were studied. These properties were compared with those in cells of patients in the leukemic phase of both malignant lymphoma, poorly differentiated lymphocytic type, and mycosis fungoides. Nuclear folding in cord blood lymphocytes was similar to that seen in lymphocytes of patients with malignant lymphoma, poorly differentiated lymphocytic type and mycosis fungoides. Surface marker characteristics of cord blood lymphocytes included increased percentages of surface IgD on cells bearing surface immunoglobulins and decreased percentages of E-rosette-forming cells. The hypothesis that both malignant lymphoma, poorly differentiated lymphocytic type and mycosis fungoides represent an arrest in the normal lymphocyte maturation sequence is discussed.

  19. Integrative Phosphoproteomics Links IL-23R Signaling with Metabolic Adaptation in Lymphocytes.

    Science.gov (United States)

    Lochmatter, Corinne; Fischer, Roman; Charles, Philip D; Yu, Zhanru; Powrie, Fiona; Kessler, Benedikt M

    2016-01-01

    Interleukin (IL)-23 mediated signal transduction represents a major molecular mechanism underlying the pathology of inflammatory bowel disease, Crohn's disease and ulcerative colitis. In addition, emerging evidence supports the role of IL-23-driven Th17 cells in inflammation. Components of the IL-23 signaling pathway, such as IL-23R, JAK2 and STAT3, have been characterized, but elements unique to this network as compared to other interleukins have not been readily explored. In this study, we have undertaken an integrative phosphoproteomics approach to better characterise downstream signaling events. To this end, we performed and compared phosphopeptide and phosphoprotein enrichment methodologies after activation of T lymphocytes by IL-23. We demonstrate the complementary nature of the two phosphoenrichment approaches by maximizing the capture of phosphorylation events. A total of 8202 unique phosphopeptides, and 4317 unique proteins were identified, amongst which STAT3, PKM2, CDK6 and LASP-1 showed induction of specific phosphorylation not readily observed after IL-2 stimulation. Interestingly, quantitative analysis revealed predominant phosphorylation of pre-existing STAT3 nuclear subsets in addition to translocation of phosphorylated STAT3 within 30 min after IL-23 stimulation. After IL-23R activation, a small subset of PKM2 also translocates to the nucleus and may contribute to STAT3 phosphorylation, suggesting multiple cellular responses including metabolic adaptation. PMID:27080861

  20. Immunomodulation by neutrophil myeloperoxidase and hydrogen peroxide: differential susceptibility of human lymphocyte functions.

    Science.gov (United States)

    el-Hag, A; Lipsky, P E; Bennett, M; Clark, R A

    1986-05-01

    The coexistence of activated polymorphonuclear leukocytes and lymphocytes in tumor masses and inflammatory tissues suggests the possibility of interaction between secreted neutrophil products and nearby lymphocytes. To test this hypothesis, we examined the effects of neutrophil myeloperoxidase and H2O2 on lymphocytes. Human peripheral blood mononuclear leukocytes were exposed to myeloperoxidase, an H2O2-generating system (glucose + glucose oxidase), and a halide, and were then tested for functional activities. Natural killer activity against K562 cells, lymphocyte proliferation in response to mitogens, and generation of immunoglobulin-secreting cells were all susceptible to oxidative injury by myeloperoxidase and H2O2. The degree as well as the mechanism of suppression was dependent on the glucose oxidase concentration (i.e., the rate of H2O2 delivery). At low H2O2 flux, myeloperoxidase was essential for induction of lymphocyte suppression; as the rate of H2O2 generation increased, suppression became myeloperoxidase-independent and was mediated by H2O2 alone. Various lymphocyte functions were differentially susceptible to oxidative injury by myeloperoxidase and H2O2. The proliferative response to poke-weed mitogen was the least sensitive, whereas antibody formation was the most sensitive. Proliferative responses to concanavalin A and phytohemagglutinin as well as natural killer activity displayed intermediate degrees of susceptibility. In all assays, lymphocyte viability was greater than 90%. Removal of monocytes from mononuclear leukocytes by adherence to glass increased susceptibility of lymphocytes to oxidative injury. Monocytes in proportions within the range present in peripheral blood mononuclear leukocytes protected lymphocyte functions against oxidative injury by myeloperoxidase and H2O2. This study demonstrates a differential susceptibility of various immune functions to oxidative injury by the neutrophil products myeloperoxidase and H2O2, and shows, in

  1. Radiomodifying effect of boron and gadolinium compounds in human peripheral lymphocytes evaluated by the comet assay

    International Nuclear Information System (INIS)

    This study was carried out to investigate the modification of radioresponse due to pretreatment of boron (Borax) and gadolinium compounds (Gd- DTPA) in human peripheral lymphocytes using the comet assay, single cell gel electrophoresis (SCGE) assay. The lymphocytes were treated with boron and gadolinium compounds for 10 minutes right before irradiation. The doses of gamma-ray were 0, 1, 2 and 4 Gy. Pretreatment with 10B (each of 50 nM and 250 nM) gave rise to a dose-dependent reduction in radiosensitivity of lymphocytes. On the other hand, pretreatment of 157 Gd- DTPA (50 nM) resulted in a dose-dependent increase in radiosensitivity, especially in the lymphocytes irradiated with 4 Gy. (P<0.001)

  2. Studying the proliferation of human peripheral blood T lymphocytes in serum-free medium.

    Science.gov (United States)

    Tabakov, V U; Litvina, M M; Schepkina, J V; Jarilin, A A; Chestkov, V V

    2009-01-01

    We compared the cultivation of human peripheral blood lymphocytes in serum-free medium Hybris-2 and RPMI 1640 medium with 10% fetal bovine serum in the presence of phytohemagglutinin and interleukin-2. The optimal concentration of phytohemagglutinin significantly differed in serum-free and serum-containing media (0.5 and 5 microg/ml, [corrected] respectively). Both mitogens were more potent in stimulating the proliferation of lymphocytes in serum-free medium than in serum-containing medium. Strong proliferation of CD3(+) and CD4(+) T lymphocytes was observed in both media. The dynamics of other markers was similar in serum-free and serum-containing media. However, significant differences were revealed between individual donors. Our results indicate that the developed serum-free medium may be used in lymphocyte cultivation for scientific, diagnostic, and therapeutic purposes.

  3. Specific high-affinity binding sites for a synthetic gliadin heptapeptide of human peripheral blood lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Payan, D.G.; Horvath, K.; Graf, L.

    1987-03-23

    The synthetic peptide containing residues 43-49 of ..cap alpha..-gliadin, the major protein component of gluten, has previously been shown to inhibit the production of lymphokine activities by mononuclear leukocytes. The authors demonstrate using radiolabeled ..cap alpha..-gliadin(43-49) that human peripheral blood lymphocytes express approximately 20,000-25,000 surface receptors for this peptide, with a dissociation constant (K/sub D/) of 20 nM. In addition, binding is inhibited by naloxone and an enkephalin analog, thus confirming the functional correlate which demonstrates inhibition by these agents of ..cap alpha..-gliadin(43-49) functional effects. Furthermore, B-lymphocytes bind specifically a greater amount of (/sup 125/I)..cap alpha..-gliadin(43-49) than T-lymphocytes. The lymphocyte ..cap alpha..-gliadin(43-49) receptor may play an important role in mediating the immunological response to ..cap alpha..-gliadin. 16 references, 4 figures.

  4. The Assessment of Cytotoxicity and Genotoxicity of Mirtazapine in Human Blood Lymphocytes Using Micronucleus Test

    Directory of Open Access Journals (Sweden)

    M Norizadeh tazehkand

    2015-02-01

    Results: MN formation was not significantly induced at 24- and 48-h treatment periods when compared with control but Nuclear division index (NDI significantly decreased at all concentrations for two treatment periods. Conclusion: Mirtazapine was not genetoxic but was cytotoxic in human peripheral blood lymphocytes. According to this study mirtazapine has cytotoxic effects on human's cells.

  5. Cytostatic and genotoxic effect of temephos in human lymphocytes and HepG2 cells.

    Science.gov (United States)

    Benitez-Trinidad, A B; Herrera-Moreno, J F; Vázquez-Estrada, G; Verdín-Betancourt, F A; Sordo, M; Ostrosky-Wegman, P; Bernal-Hernández, Y Y; Medina-Díaz, I M; Barrón-Vivanco, B S; Robledo-Marenco, M L; Salazar, A M; Rojas-García, A E

    2015-06-01

    Temephos is an organophosphorus pesticide that is used in control campaigns against Aedes aegypti mosquitoes, which transmit dengue. In spite of the widespread use of temephos, few studies have examined its genotoxic potential. The aim of this study was to evaluate the cytotoxic, cytostatic and genotoxic effects of temephos in human lymphocytes and hepatoma cells (HepG2). The cytotoxicity was evaluated with simultaneous staining (FDA/EtBr). The cytostatic and genotoxic effects were evaluated using comet assays and the micronucleus technique. We found that temephos was not cytotoxic in either lymphocytes or HepG2 cells. Regarding the cytostatic effect in human lymphocytes, temephos (10 μM) caused a significant decrease in the percentage of binucleated cells and in the nuclear division index as well as an increase in the apoptotic cell frequency, which was not the case for HepG2 cells. The comet assay showed that temephos increased the DNA damage levels in human lymphocytes, but it did not increase the MN frequency. In contrast, in HepG2 cells, temephos increased the tail length, tail moment and MN frequency in HepG2 cells compared to control cells. In conclusion, temephos causes stable DNA damage in HepG2 cells but not in human lymphocytes. These findings suggest the importance of temephos biotransformation in its genotoxic effect. PMID:25746384

  6. Arctigenin from Arctium lappa inhibits interleukin-2 and interferon gene expression in primary human T lymphocytes

    Directory of Open Access Journals (Sweden)

    Chang Shwu-Fen

    2011-03-01

    Full Text Available Abstract Background Arctium lappa (Niubang, a Chinese herbal medicine, is used to treat tissue inflammation. This study investigates the effects of arctigenin (AC, isolated from A. lappa, on anti-CD3/CD28 Ab-stimulated cell proliferation and cytokine gene expression in primary human T lymphocytes. Methods Cell proliferation was determined with enzyme immunoassays and the tritiated thymidine uptake method. Cytokine production and gene expression were analyzed with reverse transcription-polymerase chain reaction. Results AC inhibited primary human T lymphocytes proliferation activated by anti-CD3/CD28 Ab. Cell viability test indicated that the inhibitory effects of AC on primary human T lymphocyte proliferation were not due to direct cytotoxicity. AC suppressed interleukin-2 (IL-2 and interferon-γ (IFN-γ production in a concentration-dependent manner. Furthermore, AC decreased the IL-2 and IFN-γ gene expression in primary human T lymphocytes induced by anti-CD3/CD28 Ab. Reporter gene analyses revealed that AC decreased NF-AT-mediated reporter gene expression. Conclusion AC inhibited T lymphocyte proliferation and decreased the gene expression of IL-2, IFN-γ and NF-AT.

  7. Assessment of in vitro genotoxic and cytotoxic effects of flurbiprofen on human cultured lymphocytes.

    Science.gov (United States)

    Timocin, Taygun; Ila, Hasan Basri; Dordu, Tuba; Husunet, Mehmet Tahir; Tazehkand, Mostafa Norizadeh; Valipour, Ebrahim; Topaktas, Mehmet

    2016-01-01

    Flurbiprofen is non-steroidal anti-inflammatory drug which is commonly used for its analgesic, antipyretic, and anti-inflammatory effects. The purpose of the study was to explore the genotoxic and cytotoxic effects of flurbiprofen in human cultured lymphocytes by sister chromatid exchange, chromosome aberration, and cytokinesis-blocked micronucleus tests. 10, 20, 30, and 40 μg/mL concentrations of flurbiprofen (solvent is DMSO) were used to treatment of human cultured lymphocytes at two different treatment periods (24 and 48 h). Flurbiprofen had no significant genotoxic effect in any of these tests. But exposing to flurbiprofen for 24 and 48 h led to significant decrease on proliferation index, mitotic index, and nuclear division index (NDI). Also, all decreases were concentration-dependent (except NDI at 24 h treatment period). Consequently, the findings of this research showed that flurbiprofen had cytotoxic effects in human blood lymphocytes.

  8. Light microscope observation of circulating human lymphocytes cultured in vitro

    Directory of Open Access Journals (Sweden)

    Naila Francis Paulo de Oliveira

    2010-10-01

    Full Text Available The purpose of this work was to study the isolation and a light microscopy technique for cultured lymphocytes. Blood samples were obtained by venipuncture with an anticoagulant added and centrifuged in a Percoll density gradient to separate the leukocytes. Lymphocytes were placed in 25 cm ³ tissue culture flasks at 37ºC. After culturing, they were fixed and stained with the methods used for blood smears. Results showed that not all fixing solutions and stains were an equally good choice for cultured lymphocytes.Os linfócitos são células importantes do sistema imune e têm sido largamente utilizados em estudos morfológicos. Entretanto, a literatura sobre técnicas de preparação dessas células é escassa e antiga, especialmente para linfócitos cultivados in vitro. Portanto, o objetivo desse estudo foi relatar com detalhes as técnicas de isolamento e microscopia de luz de linfócitos mantidos em cultura. Amostras de sangue foram obtidas por punção venosa e centrifugadas em gradiente de densidade de Percoll, para separar os leucócitos. Os linfócitos foram mantidos em frascos de cultura de 25 cm³ a 37ºC. Após a cultura, as células foram fixadas e coradas de acordo com a metodologia utilizada para esfregaços sanguíneos. Nossos resultados mostraram que nem todos os fixadores e corantes utilizados para esfregaços sanguíneos são uma boa escolha para linfócitos cultivados in vitro.

  9. Evaluation of the genotoxic or mutagenic effects of thermal stress on cultured human lymphocytes

    OpenAIRE

    İLA, Hasan Basri; Topaktaş, Mehmet; Arslan, Mehmet; BÜYÜKLEYLA, Mehmet; İSTİFLİ, Erman Salih

    2015-01-01

    This study was performed to determine the cytogenetic effects of short-term thermal stress in human cultured lymphocytes. Experimental heat shock (39 °C) was performed alone or with the addition of mitomycin C (MMC) to determine the synergistic or antagonistic effects of heat shock on genotoxicity induced by MMC. In this study, during culture periods of 72 h, human peripheral blood lymphocytes were exposed to heat shock for specified durations (30, 60, 120, and 240 min) 24 or 48 h before harv...

  10. Relative biological effectiveness of tritiated water on human chromosomes of lymphocytes and bone marrow cells

    International Nuclear Information System (INIS)

    One of the major toxic effluent from nuclear power industries is tritiated water (HTO), which is released into the environment in large quantities. Low dose radiation effects and dose rate effects of HTO on human lymphocytes and bone marrow cells are not well studied. The present study was performed to investigate dose-response relationship for chromosome aberration frequencies in the human lymphocytes and bone marrow cells, by HTO in-vitro exposure at low dose ranges of 0.1 to 1 Gy. Go lymphocytes and bone marrow cells were incubated for 10 - 150 minutes with HTO at 2 cGy/min. Also 60Co γ and 137Cs γ rays were used as controls. Dicentric chromosomes were scored in 1,000 to 2,000 cells of each experimental series. The RBE values of HTO at low dose range for the induction of dicentric chromosomes and chromatid type aberrations were 2.7 in lymphocytes and approximately 3.8 in bone marrow cells with respect to 60Co γ ray, respectively. Also lymphocytes were chronically exposed to HTO for 24 to 72 hrs at lower dose rates (0.2 and 0.05 cGy/min). The yields of dicentrics and rings decreased with the reduction in the dose rate of HTO, presenting a clear dose rate effects of HTO. These results provide an useful information for the assessment for health risk in humans exposed to low concentration level to HTO. (author)

  11. Suppressive effect of Chinese medicinal herb, Acanthopanax gracilistylus, extract on human lymphocytes in vitro.

    Science.gov (United States)

    Shan, B E; Yoshita, Y; Sugiura, T; Yamashita, U

    1999-10-01

    We studied the effect of a Chinese medicinal herb, Acanthopanax gracilistylus, extract (AGE), on human lymphocytes in vitro. AGE markedly suppressed the proliferative responses of human peripheral blood lymphocytes stimulated with mitogens concanavalin A (Con A) and Staphylococcus aureus Cowan I (SAC). Both T cell and B cell activities-production of interferon-gamma and immunoglobulin-were suppressed by AGE. The mechanism of AGE-induced suppression of lymphocytes is to arrest the cell cycle at the G0/G1 stage without a direct cytotoxic effect. AGE also suppressed the alloantigen-specific cytotoxic T lymphocyte response. However, natural killer cell activity was less sensitive to the suppressive activity of AGE. In contrast, AGE markedly enhanced monocyte function to produce cytokines. These activities of AGE were associated with a 60-kD protein which was sensitive to treatment with pronase E, but not with NaIO4. These results suggest that AGE has an immunomodulating activity on human lymphocytes and its properties could be clinically applied in the treatment of several diseases such as autoimmune and allergic diseases. PMID:10540158

  12. Radioprotective effect of chicory seeds against genotoxicity induced by ionizing radiation in human normal lymphocytes.

    Science.gov (United States)

    Hosseinimehr, S J; Ghaffari-Rad, V; Rostamnezhad, M; Ghasemi, A; Allahverdi Pourfallah, T; Shahani, S

    2015-01-01

    The search for less-toxic radioprotective agents has led to a growing trend towards natural products. Protective effect of the methanolic extract of chicory seeds (MCS) was investigated against genotoxicity induced by ionizing radiation in human lymphocytes. Human peripheral blood samples were collected and incubated with MCS at different concentrations (10, 50, 100, and 200 μg/mL) for two hours. The whole blood samples were exposed in vitro to X-ray at dose 2.5 Gy. Then, the lymphocytes were cultured with mitogenic stimulation to determine the micronucleus in cytokinesis blocked binucleated cell. The methanolic extract at all doses significantly reduced the frequency of micronuclei in binucleated lymphocytes, as compared with similarly irradiated lymphocytes without any extract treatment. The maximum protection was observed at 200 μg/mL of MCS, it completely protected genotoxicity induced by ionizing radiation in human lymphocytes. The extract exhibited a concentration-dependent radical scavenging activity on 1,1-diphenyl-2-picryl hydrazyl free radicals. HPLC analysis of MCS showed this extract is containing chlorogenic acid as a phenolic compound. These data suggest that the radioprotective effect of methanolic extract of chicory seeds can be attributed to the presence of phenolic compounds such as chlorogenic acid which act as antioxidant agents. PMID:26278267

  13. Lamprey buccal gland secretory protein-2 (BGSP-2 inhibits human T lymphocyte proliferation

    Directory of Open Access Journals (Sweden)

    Jing SUN, Shuiyan YU, Zhuang XUE, Cenjie LIU, Yu WU, Xin LIU, Qingwei LI

    2010-04-01

    Full Text Available Lamprey is a representative of the agnathans, the most ancient class of vertebrates. Parasitic lampreys secrete anticoagulant from their buccal glands and prevent blood coagulation of host fishes. We identified a buccal gland secretory protein-2 (BGSP-2 from a buccal gland cDNA library of Lampetra japonica. The full-length BGSP-2 gene was cloned and the recombinant BGSP-2 protein was generated. The role of BGSP-2 on lymphocyte proliferation was studied by examining its effects on human T lymphocytes. We found that lamprey BGSP-2 was able to effectively block the proliferation of T cells in vitro by inducing G1/S cell cycle arrest. Furthermore, it inhibited the proliferation of human T lymphocytes stimulated by phytohemagglutinin (PHA at a minimum concentration of 0.1μg/ml. Our data suggest that lamprey BGSP-2 is able to block the mitosis of human T lymphocytes at the G1/S point, and has the potential of anti-proliferative effect on PHA-activated T lymphocytes [Current Zoology 56 (2: 252–258, 2010].

  14. Immunosuppression in Human Peripheral Blood T Lymphocytes by Fluvastatin

    Institute of Scientific and Technical Information of China (English)

    Li-Hua WU; Yun-Le WAN; Hai-Yang XIE; Wen-Jin ZHANG; Shu-Sen ZHENG

    2004-01-01

    To investigate the immunosuppressive effect offluvastatin on the PHA-activated T lymphocytes.T lymphocytes were isolated from the blood of healthy volunteers, cell proliferation and the activation markers expression were examined by flow cytometric analysis. Cytokine secretion was assayed by ELISA.LDH-release assay was used to detect activity of killer cells. NFAT activation was evaluated by TransAMTM ELISA kit. Results were as following. (1) Whereas no modification in CD25 expression was seen, fluvastatin at 5 μM caused a lower level of CD69 expression, accompanied by an essential suppression on proliferation,IL-2 production and cytotoxicity development in PHA-stimulated T cells. However, the level of secreted IL-10 had no change, and the level of IL-4 even experienced a significant increase. (2) Combined with cyclosporine A (CsA), fluvastatin would further repress CD69 expression, cells proliferation and activity of killer cells, meanwhile significantly induced the secretion of IL-4 and IL-10. (3) Fluvastatin treatment also resulted in a strong inhibition of NFAT activation. In conclusion, partly involving the blockage of activation of NFAT, fluvastatin exhibited an immunosuppressive effect in vitro.

  15. Human Maternal Brain Plasticity: Adaptation to Parenting.

    Science.gov (United States)

    Kim, Pilyoung

    2016-09-01

    New mothers undergo dynamic neural changes that support positive adaptation to parenting and the development of mother-infant relationships. In this article, I review important psychological adaptations that mothers experience during pregnancy and the early postpartum period. I then review evidence of structural and functional plasticity in human mothers' brains, and explore how such plasticity supports mothers' psychological adaptation to parenting and sensitive maternal behaviors. Last, I discuss pregnancy and the early postpartum period as a window of vulnerabilities and opportunities when the human maternal brain is influenced by stress and psychopathology, but also receptive to interventions. PMID:27589497

  16. Studying the replication history of human B lymphocytes by real-time quantitative (RQ)-PCR.

    Science.gov (United States)

    van Zelm, Menno C; Berkowska, Magdalena A; van Dongen, Jacques J M

    2013-01-01

    The cells of the adaptive immune system, B and T lymphocytes, each generate a unique antigen receptor through V(D)J recombination of their immunoglobulin (Ig) and T cell receptor (TCR) loci, respectively. Such rearrangements join coding elements to form a coding joint and delete the intervening DNA as circular excision products containing the signal joint. These excision circles are stable structures that cannot replicate and have no function in the cell. Since the coding joint in the genome is replicated with each cell division, the ratio between coding joints and signal joints in a population of B cells can be used as a measure for proliferation. This chapter describes a real-time quantitative (RQ-)PCR-based approach to quantify proliferation through calculating the ratio between coding joints and signal joints of the frequently occurring intronRSS-Kde rearrangements in the IGK light chain locus. The approach is useful to study basic B-cell biology as well as abnormal proliferation in human diseases.

  17. In vitro effects of Thai medicinal plants on human lymphocyte activity

    Directory of Open Access Journals (Sweden)

    Pranee Chavalittumrong

    2007-03-01

    Full Text Available We assessed the effects of Cleistocalyx nervosum var paniala, Gynostemma pentaphyllum, Gynura procumbens, Houttuynia cordata, Hyptis suaveolens, Portulaca grandiflora, Phytolacca americana and Tradescantia spathacea on lymphocyte proliferation and the effects of C. nervosum, G. pentaphyllum, H. suaveolens and P. grandiflora on natural killer (NK cells activity. All of the extracts significantly stimulated human lymphocyte proliferative responses at various concentrations depending on each extract. The extracts of C. nervosum and H. suaveolens were significantly enhanced NK cells activity while those of G. pentaphyllum and P. grandiflora did not alter NK cells function. Our results suggested that the extracts of those plants have stimulating activity on human lymphocytes and could be clinically useful for modulating immune functions of the body.

  18. Human thiopurine methyltransferase pharmacogenetics: effect of phenotype on sensitivity of cultured lymphocytes to 6-mercaptopurine

    Energy Technology Data Exchange (ETDEWEB)

    Van Loon, J.; Weinshilboum, R.

    1986-03-05

    Thiopurine methyltransferase (EC 2.1.1.67, TPMT) catalyzes the S-methylation of thiopurine drugs such as 6-mercaptopurine (6-MP). TPMT activity in human lymphocytes and other tissues is controlled by a common genetic polymorphism. These experiments were designed to study the relationship between TPMT phenotype and the effect of 6-MP on /sup 3/H-thymidine (/sup 3/H-TdR) incorporation into phytohemaglutinin (PHA) stimulated human peripheral blood lymphocytes. Lymphocytes were obtained from the blood of nine subjects, three subjects with each TPMT phenotype. 6-MP dose response curves were performed at optimal (10 ..mu..g/ml) and suboptimal (1 ..mu..g/ml) concentrations of PHA. ED50 values for 6-MP with lymphocytes from subjects who genetically lacked TPMT activity were higher than ED50 values for lymphocytes from subjects with genetically intermediate or high TPMT activity. However, ED50 values decreased as level of stimulation increased. Therefore, the effects of 6-MP were studied at a series of PHA concentrations that ranged from 0.1 ..mu..g/ml to 10 ..mu..g/ml. Lymphocytes from subjects who lacked TPMT activity had significantly higher K/sub ii/ values (1.37 +/- 0.340 ..mu..M; mean +/- SEM) for inhibition of /sup 3/H-TdR incorporation by 6-MP than did lymphocytes from subjects with intermediate or high TPMT activity (0.529 +/- 0.068 ..mu..M and 0.327 +/- 0.064 ..mu..M, respectively, P < .05 for both comparisons).

  19. Antibacterial activity of neem nanoemulsion and its toxicity assessment on human lymphocytes in vitro.

    Science.gov (United States)

    Jerobin, Jayakumar; Makwana, Pooja; Suresh Kumar, R S; Sundaramoorthy, Rajiv; Mukherjee, Amitava; Chandrasekaran, Natarajan

    2015-01-01

    Neem (Azadirachta indica) is recognized as a medicinal plant well known for its antibacterial, antimalarial, antiviral, and antifungal properties. Neem nanoemulsion (NE) (O/W) is formulated using neem oil, Tween 20, and water by high-energy ultrasonication. The formulated neem NE showed antibacterial activity against the bacterial pathogen Vibrio vulnificus by disrupting the integrity of the bacterial cell membrane. Despite the use of neem NE in various biomedical applications, the toxicity studies on human cells are still lacking. The neem NE showed a decrease in cellular viability in human lymphocytes after 24 hours of exposure. The neem NE at lower concentration (0.7-1 mg/mL) is found to be nontoxic while it is toxic at higher concentrations (1.2-2 mg/mL). The oxidative stress induced by the neem NE is evidenced by the depletion of catalase, SOD, and GSH levels in human lymphocytes. Neem NE showed a significant increase in DNA damage when compared to control in human lymphocytes (P<0.05). The NE is an effective antibacterial agent against the bacterial pathogen V. vulnificus, and it was found to be nontoxic at lower concentrations to human lymphocytes. PMID:26491309

  20. Antibacterial activity of neem nanoemulsion and its toxicity assessment on human lymphocytes in vitro.

    Science.gov (United States)

    Jerobin, Jayakumar; Makwana, Pooja; Suresh Kumar, R S; Sundaramoorthy, Rajiv; Mukherjee, Amitava; Chandrasekaran, Natarajan

    2015-01-01

    Neem (Azadirachta indica) is recognized as a medicinal plant well known for its antibacterial, antimalarial, antiviral, and antifungal properties. Neem nanoemulsion (NE) (O/W) is formulated using neem oil, Tween 20, and water by high-energy ultrasonication. The formulated neem NE showed antibacterial activity against the bacterial pathogen Vibrio vulnificus by disrupting the integrity of the bacterial cell membrane. Despite the use of neem NE in various biomedical applications, the toxicity studies on human cells are still lacking. The neem NE showed a decrease in cellular viability in human lymphocytes after 24 hours of exposure. The neem NE at lower concentration (0.7-1 mg/mL) is found to be nontoxic while it is toxic at higher concentrations (1.2-2 mg/mL). The oxidative stress induced by the neem NE is evidenced by the depletion of catalase, SOD, and GSH levels in human lymphocytes. Neem NE showed a significant increase in DNA damage when compared to control in human lymphocytes (P<0.05). The NE is an effective antibacterial agent against the bacterial pathogen V. vulnificus, and it was found to be nontoxic at lower concentrations to human lymphocytes.

  1. Purification and characterization of an inhibitor of thymidine uptake from culture supernatants of human tonsil lymphocytes

    International Nuclear Information System (INIS)

    Lymphocytes from human tonsils were cultured in the absence of serum for 3 days. In the presence of the concentrated culture supernatant the proliferative response of PBL, to con A, as measured by the uptake of 3H-tdr, was significantly reduced. The suppressor substance was referred to as SMAL (suppressor of mitogen activated lymphocytes). The estimated molecular weight of SMAL under nondenaturing conditions was 100,000-300,000. SMAL also suppressed the incorporation of 3H-tdr by a variety of mouse and human tumor cell lines. The activity of SMAL was sensitive to pronase and heating at 1000C for 30 minutes but insensitive to RNase. Treatment with DNase, however, enhanced the activity of SMAL. SMAL was not produced by heat-killed tonsil lymphocytes or lymphocytes-treated with cycloheximide. Maximal production occurred in the first 24 hours of culture, and progressively less was produced in subsequent 24-hour intervals. Both T- and B lymphocyte-enriched culture supernatants contained SMAL. Two active components, one corresponding to a large and/or less negatively charged molecule and another corresponding to small and/or highly acidic molecule, were recovered. HPLC-purified SMAL at relatively low doses inhibited the uptake and phosphorylation of 3H-tdr, without significant effect on cell proliferation. The inhibition of 3H-tdr uptake was favored over that of 3H-udr or 3H-adr, and this effect was reversible

  2. Manifestation of radiaton injury of human lymphocytes using PHA mitogenic stimulation in different culture systems

    International Nuclear Information System (INIS)

    The proliferative response of human lymphocytes to phytohemagglutinin in vitro is affected by X-irradiation. Dose-related changes in mitogenic stimulation of irradiated lymphocytes were compared for two culture systems - the cultivation of separated lymphocytes and the cultivation of whole blood. In the whole blood cultures, the proliferative activity of stimulated lyphocytes was markedly and reproducibly depressed by irradiation. An exponential curve could be fitted to the values of mitogenic response within a dose range from 0 to 2.5 Gy with high correlation. In a modified test where the mitogenic stimulus was given after a 24 h delay, depression in the response was even more pronounced. Radiosensitivity of human lymphocytes as determined by means of mitogenic stimulation in the whole blood cultures appears to be a characteristic individual feature. The mean D37 value of the radiation-induced depression in mitogenic response in a group of 20 healthy donors was 2.5 Gy in the standard test and 2.0 Gy in the test with a delayed mitogenic stimulus. In contrast, the data obtained from separated lymphocyte cultures were characterized by a high degree of test-to-test variability and by much lower radiosensitivity. The possible mechanisms of these distinctive manifestations of the same primary radiation injury are discussed. (author) 3 tabs., 2 figs., 12 refs

  3. Intracellular calcium mobilization in human lymphocytes in the presence of synthetic IgG Fc peptides

    Energy Technology Data Exchange (ETDEWEB)

    Plummer, J.M.; Panahi, Y.P.; McClurg, M.R.; Hahn, G.S.; Naemura, J.R.

    1986-03-01

    Certain synthetic peptides derived from the Fc region of human IgG can suppress the mixed lymphocyte response. These peptides were tested for the ability to induce intracellular calcium mobilization in human lymphocytes using fura-2/calcium fluorescence. T cells were isolated by rosetting and were > 90% OKT3 positive. Lymphocytes were incubated with the acetoxymethyl ester of fura-2 (10 ..mu..M) for 60 minutes at 37/sup 0/C. Fluorescence intensity changes at 505 nm were monitored at an excitation lambda of 340 nm. Fura-2 was not cytotoxic compared to quin-2 since fura-2 loaded mononuclear cells incorporated /sup 3/H-thymidine when stimulated by PHA, succinyl Con A, PWM or LPS-STM whereas quin-2 loaded cells showed a dose dependent inhibition of proliferation. Those synthetic peptides (5 to 400 ..mu..g/ml) that suppressed the MLR induced a dose dependent increase in intracellular calcium in mononuclear cells, lymphocytes, non-T cells and T cells. The fura-2 calcium fluorescence time course response was similar for peptide, PHA and succinyl Con A. These results suggest that these immunoregulatory peptides suppress /sup 3/H-thymidine incorporation at a point after intracellular calcium mobilization and that fura-2 has advantages over quin-2 in measuring intracellular calcium levels in lymphocytes.

  4. Intracellular calcium mobilization in human lymphocytes in the presence of synthetic IgG Fc peptides

    International Nuclear Information System (INIS)

    Certain synthetic peptides derived from the Fc region of human IgG can suppress the mixed lymphocyte response. These peptides were tested for the ability to induce intracellular calcium mobilization in human lymphocytes using fura-2/calcium fluorescence. T cells were isolated by rosetting and were > 90% OKT3 positive. Lymphocytes were incubated with the acetoxymethyl ester of fura-2 (10 μM) for 60 minutes at 370C. Fluorescence intensity changes at 505 nm were monitored at an excitation lambda of 340 nm. Fura-2 was not cytotoxic compared to quin-2 since fura-2 loaded mononuclear cells incorporated 3H-thymidine when stimulated by PHA, succinyl Con A, PWM or LPS-STM whereas quin-2 loaded cells showed a dose dependent inhibition of proliferation. Those synthetic peptides (5 to 400 μg/ml) that suppressed the MLR induced a dose dependent increase in intracellular calcium in mononuclear cells, lymphocytes, non-T cells and T cells. The fura-2 calcium fluorescence time course response was similar for peptide, PHA and succinyl Con A. These results suggest that these immunoregulatory peptides suppress 3H-thymidine incorporation at a point after intracellular calcium mobilization and that fura-2 has advantages over quin-2 in measuring intracellular calcium levels in lymphocytes

  5. Determination of Amino Acids in Single Human Lymphocytes after On-capillary Derivatization by Capillary Zone Electrophoresis with Electrochemical Detection

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Amino acids in individual human lymphocytes were determined by capillary zone electrophoresis with electrochemical detection after on-capillary derivatization. In order to inject cells easily, a cell injector was designed. Four amino acids (serine, alanine, taurine, and glycine) in single human lymphocytes have been identified. Quantitation has been accomplished through the use of calibration curves.

  6. Inorganic arsenic represses interleukin-17A expression in human activated Th17 lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Morzadec, Claudie; Macoch, Mélinda; Robineau, Marc; Sparfel, Lydie [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France); Fardel, Olivier [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France); Pôle Biologie, Centre Hospitalier Universitaire (CHU) Rennes, 2 rue Henri Le Guilloux, 35033 Rennes (France); Vernhet, Laurent, E-mail: laurent.vernhet@univ-rennes1.fr [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France)

    2012-08-01

    Trivalent inorganic arsenic [As(III)] is an efficient anticancer agent used to treat patients suffering from acute promyelocytic leukemia. Recently, experimental studies have clearly demonstrated that this metalloid can also cure lymphoproliferative and/or pro-inflammatory syndromes in different murine models of chronic immune-mediated diseases. T helper (Th) 1 and Th17 lymphocytes play a central role in development of these diseases, in mice and humans, especially by secreting the potent pro-inflammatory cytokine interferon-γ and IL-17A, respectively. As(III) impairs basic functions of human T cells but its ability to modulate secretion of pro-inflammatory cytokines by differentiated Th lymphocytes is unknown. In the present study, we demonstrate that As(III), used at concentrations clinically achievable in plasma of patients, has no effect on the secretion of interferon-γ from Th1 cells but almost totally blocks the expression and the release of IL-17A from human Th17 lymphocytes co-stimulated for five days with anti-CD3 and anti-CD28 antibodies, in the presence of differentiating cytokines. In addition, As(III) specifically reduces mRNA levels of the retinoic-related orphan receptor (ROR)C gene which encodes RORγt, a key transcription factor controlling optimal IL-17 expression in fully differentiated Th17 cells. The metalloid also blocks initial expression of IL-17 gene induced by the co-stimulation, probably in part by impairing activation of the JNK/c-Jun pathway. In conclusion, our results demonstrate that As(III) represses expression of the major pro-inflammatory cytokine IL-17A produced by human Th17 lymphocytes, thus strengthening the idea that As(III) may be useful to treat inflammatory immune-mediated diseases in humans. -- Highlights: ► Arsenic inhibits secretion of IL-17A from human naïve and memory Th17 lymphocytes. ► Arsenic represses early expression of IL-17A gene in human activated T lymphocytes. ► Arsenic interferes with activation of

  7. Natural background radiation induces cytogenetic radioadaptive response more effectively than occupational exposure in human peripheral blood lymphocytes

    International Nuclear Information System (INIS)

    Ramsar, a city in the north part of Iran, has the highest level of natural background radiation in the world. We compared induction of cytogenetic radioadaptive response by High Natural Background Radiation (HNBR) in Ramsar and X-Ray occupational exposure as inducing doses in human peripheral blood lymphocytes. 30 healthy control individuals, living in Ramsar but in ordinary background radiation areas (inducing dose = 0), 15 healthy individuals from Talesh Mahalleh, a region with extraordinary level of background radiation (max. inducing dose = 260 mGy/year) and 7 X-Ray radiographers working in Ramsar hospital located in normal natural background of ionising radiation (max. inducing dose = 20 mGy/year) were evaluated. Peripheral blood samples were prepared and exposed to challenge dose of 0 and 2 Gy. Lymphocytes were scored using analysis of metaphase, for the presence of chromosomal aberrations (simple deletion, dicentrics and rings). An adaptive response was observed in HNBR and radiation workers groups in comparison with sham controls. Also, compared with occupationally exposed group a significant marked increase in adaptive response was observed in HNBR group. These findings indicate that both natural background radiation and occupational exposure could induce cytogenetic radioadaptive response and it is more significant regarding to natural background ionising radiation. (author)

  8. Reactivity of eleven anti-human leucocyte monoclonal antibodies with lymphocytes from several domestic animals

    DEFF Research Database (Denmark)

    Aasted, Bent; Blixenkrone-Møller, Merete; Larsen, Else Bang;

    1988-01-01

    Nine commercially available monoclonal antibodies and two monoclonal antibodies from The American Type Culture Collection, raised against various human leucocyte surface antigens, were tested on lymphocytes from cow, sheep, goat, swine, horse, cat, dog, mink, and rabbit as well as man. Four...

  9. A biophysical model applied to survival of tumor cells and chromosomal aberrations in human lymphocytes

    International Nuclear Information System (INIS)

    Investigations on survival of tumor cells E.M.T.6 and chromosomal aberrations in human lymphocytes irradiated in vitro and microdosimetric studies were made using a helion beam. The results obtained were compared in order to see if the Dual Radiation Action Theory of ROSSI and KELLERER can explain these radiobiological phenomena

  10. Response of human lymphocyte chromosomes to fractionated neutron irradiation in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Sevan' kaev, A.V.; Nasonova, V.A.; Golovinova, G.I. (Akademiya Meditsinskikh Nauk SSSR, Obninsk. Nauchno-Issledovatel' skij Inst. Meditsinskoj Radiologii)

    A comparative study was made of the yield of chromosome aberrations in a human lymphocyte culture after a single and fractionated exposure to neutron radiation at the beginning of the G/sub 1/ phase and during the S phase of the mitotic cycle. It was shown that the degree of the chromosome affection in both phases does not depend upon the irradiation schedules.

  11. SFTG international collaborative study on in vitro micronucleus test. II. Using human lymphocytes

    NARCIS (Netherlands)

    Clare, M.G.; Lorenzon, G.; Akhurst, L.C.; Marzin, D.; Delft, J. van; Montero, R.; Botta, A.; Bertens, A.; Cinelli, S.; Thybaud, V.; Lorge, E.

    2006-01-01

    This study on the in vitro micronucleus assay, comprising 11 laboratories using human lymphocytes, was coordinated by an organizing committee supported by the SFTG (the French branch of the European Environmental Mutagen Society). Nine coded substances were assessed for their ability to induce micro

  12. The Effect of a Grape Seed Extract on Radiation-Induced DNA Damage in Human Lymphocytes

    Science.gov (United States)

    Dicu, Tiberius; Postescu, Ion D.; Foriş, Vasile; Brie, Ioana; Fischer-Fodor, Eva; Cernea, Valentin; Moldovan, Mircea; Cosma, Constantin

    2009-05-01

    Plant-derived antioxidants due to their phenolic compounds content are reported as potential candidates for reducing the levels of oxidative stress in living organisms. Grape seed extracts are very potent antioxidants and exhibit numerous interesting pharmacologic activities. Hydroethanolic (50/50, v/v) standardized extract was obtained from red grape seed (Vitis vinifera, variety Burgund Mare—BM). The total polyphenols content was evaluated by Folin-Ciocalteu procedure and expressed as μEq Gallic Acid/ml. The aim of this study was to evaluate the potential antioxidant effects of different concentrations of BM extract against 60Co γ-rays induced DNA damage in human lymphocytes. Samples of human lymphocytes were incubated with BM extract (12.5, 25.0 and 37.5 μEq GA/ml, respectively) administered at 30 minutes before in vitro irradiation with γ-rays (2 Gy). The DNA damage and repair in lymphocytes were evaluated using alkaline comet assay. Using the lesion score, the radiation-induced DNA damage was found to be significantly different (p<0.05) from control, both in the absence and presence of BM extract (except the lymphocytes treated with 37.5 μEq GA/ml BM extract). DNA repair analyzed by incubating the irradiated cells at 37° C and 5% CO2 atmosphere for 2 h, indicated a significant difference (p<0.05) in the lymphocytes group treated with 25.0 μEq GA/ml BM extract, immediately and two hours after irradiation. These results suggest radioprotective effects after treatment with BM extract in human lymphocytes.

  13. Persistent Infection of Epstein-Barr Virus-Positive B Lymphocytes by Human Herpesvirus 8

    OpenAIRE

    Kliche, S; E. Kremmer; Hammerschmidt, W; Koszinowski, U; Haas, J.

    1998-01-01

    In patients with Kaposi's sarcoma (KS), human herpesvirus 8 (HHV-8) can invariably be detected in KS tumor tissue and, at a lower frequency, in prostate tissue and peripheral blood B lymphocytes. Whereas the majority of KS spindle cells are latently infected by HHV-8, linear HHV-8 genomes characteristic for lytic infection are found predominantly in the peripheral blood cells of BS patients. In this study, we show that HHV-8 can stably infect B lymphocytes in vitro in the presence of Epstein-...

  14. ATP, a partial agonist for the P2Z receptor of human lymphocytes

    OpenAIRE

    Gargett, Caroline E.; Cornish, Jean E; Wiley, James S.

    1997-01-01

    Although extracellular adenosine 5′-triphosphate (ATP) is the natural ligand for the P2Z receptor of human lymphocytes it is less potent than 3′-O-(4-benzoylbenzoyl)-ATP (BzATP) in opening the associated ion channel, which conducts a range of permeants including Ba2+ and ethidium+. We have quantified the influx of ethidium+ into lymphocytes produced by BzATP, ATP, 2-methylthio-ATP (2MeSATP) and ATPγS, studied competition between ATP and BzATP and investigated the effects of KN-62, a new and p...

  15. Human Prolactin Improves Engraftment and Reconstitution of Human Peripheral Blood Lymphocytes in SCID Mice

    Institute of Scientific and Technical Information of China (English)

    Rui Sun; Jian Zhang; Cai Zhang; Jianhua Zhang; Shujuan Liang; Anyuan Sun; Junfu Wang; Zhigang Tian

    2004-01-01

    Recombinant human prolactin (rhPRL) was administered to huPBL-SCID mice to determine its effects on human immunologic reconsfitution and function. The huPBL-SCID mice were given 10 μg I.p. Injection of rhPRL every other day for a total of 10 injections after huPBL were transferred. The results demonstrated that rhPRL improved the engraftment of lymphocytes into thymus, lymph nodes and spleens, showing that the cellularities of these organs increased although the cellularities tended to vary depending on the donor. The amounts of human T cells (HLA-ABC+/CD3+) increased greatly in thymus (14.2 folds), spleen (4.16 folds) and lymph nodes (40.18 folds) after rhPRL injections. The amounts of human B cells (HLA-ABC+/CD19+) also increased greatly in lymph nodes (42.5 folds) and spleen (5.78 folds). The lymph node cells from the rhPRL-treated huPBL-SCID mice were more sensitive to PHA stimulation ([3H] thymidine incorporation). The supernatant of PHA-stimulated PBL from rhPRL-treated huPBL/SCID chimerism contained more cytokines (IFN-γ and IL-2). The natural cytotoxicity against human sensitive target cells, K562 cells, from spleen and bone marrow of hPBL/SCID chimerism was significantly enhanced by rhPRL administration. The lymph node cells were stimulated with LPS in vitro for 3 days and the lymphocytes from the rhPRL-treated huPBL-SCID mice were more sensitive to mitogen stimulation. Both serum total IgG level and IgM level of rhPRL-treated huPBL/SCID chimerism were increased, and even without DT-rechallenge the base line of DT-specific IgG was elevated after rhPRL treatment in huPBL-SCID mice. Thus, rhPRL stimulation promotes reconstitution of human immune system in huPBL-SCID mice.

  16. Human Prolactin Improves Engraftment and Reconstitution of Human Peripheral Blood Lymphocytes in SCID Mice

    Institute of Scientific and Technical Information of China (English)

    RuiSun; JianZhang; CaiZhang; JianhuaZhang; ShujuanLiang; AnyuanSun; JunfuWang; ZhigangTian

    2004-01-01

    Recombinant human prolactin (rhPRL) was administered to huPBL-SCID mice to determine its effects on human immunologic reconstitution and function. The huPBL-SCID mice were given 10 μg i.p. injection of rhPRL every other day for a total of 10 injections after huPBL were transfered. The results demonstrated that rhPRL improved the engraftment of lymphocytes into thymus, lymph nodes and spleens, showing that the cellularities of these organs increased although the cellularities tended to vary depending on the donor. The amounts of human T cells (HLA-ABC+/CD3+) increased greatly in thymus (14.2 folds), spleen (4.16 folds) and lymph nodes (40.18 folds) after rhPRL injections. The amounts of human B cells (HLA-ABC+/CD19+) also increased greatly in lymph nodes (42.5 folds) and spleen (5.78 folds). The lymph node cells from the rhPRL-treated huPBL-SCID mice were more sensitive to PHA stimulation (〔3H〕thymidine incorporation). The supernatant of PHA-stimulated PBL from rhPRL-treated huPBL/SCID chimerism contained more cytokines (IFN-γ and IL-2). The natural cytotoxicity against human sensitive target cells, K562 cells, from spleen and bone marrow of hPBL/SCID chimerism was significantly enhanced by rhPRL administration. The lymph node cells were stimulated with LPS in vitro for 3 days and the lymphocytes from the rhPRL-treated huPBL-SCID mice were more sensitive to mitogen stimulation. Both serum total IgG level and IgM level of rhPRL-treated huPBL/SCID chimerism were increased, and even without DT-rechallenge the base line of DT-specific IgG was elevated after rhPRL treatment in huPBL-SCID mice. Thus, rhPRL stimulation promotes reconstitution of human immune system in huPBL-SCID mice. Cellular & Molecular Immunology. 2004;1(2):129-136.

  17. An adaptive paradigm for human space settlement

    Science.gov (United States)

    Smith, Cameron M.

    2016-02-01

    Because permanent space settlement will be multigenerational it will have to be viable on ecological timescales so far unfamiliar to those planning space exploration. Long-term viability will require evolutionary and adaptive planning. Adaptations in the natural world provide many lessons for such planning, but implementing these lessons will require a new, evolutionary paradigm for envisioning and carrying out Earth-independent space settlement. I describe some of these adaptive lessons and propose some cognitive shifts required to implement them in a genuinely evolutionary approach to human space settlement.

  18. Protective Effect of Curcumin on γ - radiation Induced Chromosome Aberrations in Human Blood Lymphocytes

    International Nuclear Information System (INIS)

    The present work is aimed at evaluating the radioprotective effect of curcumin on γ radiation induced genetic toxicity. The DNA damage was analyzed by the frequencies of chromosome aberrations assay. Human lymphocytes were treated in vitro with 5.0 γg/ml of curcumin for 30 min at 37 degree C then exposed to 1, 2 and 4 Gy gamma-radiation. The lymphocytes which were pre-treated with curcumin exhibited a significant decrease in the frequency of chromosome aberration at 1 and 2 Gy radiation-induced chromosome damage as compared with the irradiated cells which did not receive the curcumin pretreatment. Thus, pretreatment with curcumin gives protection to lymphocytes against γ-radiation induced chromosome aberration at certain doses. (author)

  19. [Chromosome aberrations in human lymphocytes at a various duration of cultivation after irradiation].

    Science.gov (United States)

    Riabchenko, N I; Antoshchina, M M; Nasonova, V A; Fesenko, E V; Gotlib, V Ia

    2004-01-01

    Human peripheral blood lymphocytes were exposed to 60Co gamma-rays (a dose of 3 Gy) and cultivated during seven days in the presence of PHA and BrdU. It was shown that the metaphases of the first and second mitosises occurred during cultivation of the irradiated and unirradiated lymphocytes, being evidence about of irregularity of the coming into division of various fractions of lymphocytes. The time of cultivation did not influence a rate of aberrations in metaphases of the first and second mitosises of the irradiated lymphocytes. During the first and the subsequent mitosises the number of exchange chromosome aberrations decreased and reached a control level in metaphases of the fourth and fifth mitosises. The number of paired fragments at second and third mitosises increased a little and started to decrease only in metaphases of the fourth and fifth mitosises. The decrease in chromosome aberrations with prolongation of the cultivation of lymphocytes after irradiating is a consequence of elimination of cells with chromosome damages during sequential mitotic divisions.

  20. Drinking beer reduces radiation-induced chromosome aberrations in human lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Monobe, Manami [Chiba Univ. (Japan). Graduate School of Science and Technology; Ando, Koichi [National Inst. of Radiological Sciences, Chiba (Japan)

    2002-09-01

    We here investigated and reported the effects of beer drinking on radiation-induced chromosome aberrations in blood lymphocytes. Human blood that was collected either before or after drinking a 700 ml beer was in vitro irradiated with 200 kVp X rays or 50 keV/{mu}m carbon ions. The relation between the radiation dose and the aberration frequencies (fragments and dicentrics) was significantly (P<0.05) lower for lymphocytes collected 3 h after beer drinking than those before drinking. Fitting the dose response to a linear quadratic model showed that the alpha term of carbon ions was significantly (P<0.05) decreased by beer drinking. A decrease of dicentric formation was detected as early as 0.5 h after beer drinking, and lasted not shorter than 4.5 h. The mitotic index of lymphocytes was higher after beer drinking than before, indicating that a division delay would not be responsible for the low aberrations induced by beer drinking. An in vitro treatment of normal lymphocytes with 0.1 M ethanol, which corresponded to a concentration of 6-times higher than the maximum ethanol concentration in the blood after beer drinking, reduced the dicentric formation caused by X-ray irradiation, but not by carbon-ion irradiation. The beer-induced reduction of dicentric formation was not affected by serum. It is concluded that beer could contain non-ethanol elements that reduce the chromosome damage of lymphocytes induced by high-LET radiation. (author)

  1. Toxicological Implications and Inflammatory Response in Human Lymphocytes Challenged with Oxytetracycline.

    Science.gov (United States)

    Di Cerbo, A; Palatucci, A T; Rubino, V; Centenaro, S; Giovazzino, A; Fraccaroli, E; Cortese, L; Ruggiero, G; Guidetti, G; Canello, S; Terrazzano, G

    2016-04-01

    Antibiotics are widely used in zoo technical and veterinary practices as feed supplementation to ensure wellness of farmed animals and livestock. Several evidences have been suggesting both the toxic role for tetracyclines, particularly for oxytetracycline (OTC). This potential toxicity appears of great relevance for human nutrition and for domestic animals. This study aimed to extend the evaluation of such toxicity. The biologic impact of the drug was assessed by evaluating the proinflammatory effect of OTC and their bone residues on cytokine secretion by in vitro human peripheral blood lymphocytes. Our results showed that both OTC and OTC-bone residues significantly induced the T lymphocyte and non-T cell secretion of interferon (IFN)-γ, as cytokine involved in inflammatory responses in humans as well as in animals. These results may suggest a possible implication for new potential human and animal health risks depending on the entry of tetracyclines in the food-processing chain. PMID:26537863

  2. Benzo(a)pyrene activation and detoxification by human pulmonary alveolar macrophages and lymphocytes

    International Nuclear Information System (INIS)

    Comparisons of pulmonary alveolar macrophages and circulating lymphocytes from five smokers and five nonsmokers for their ability to metabolize benzo(a)pyrene as determined by high pressure liquid chromatography were carried out. Utilizing this approach, further investigation of activation and detoxification by several human cell types could provide the basis for more precise and comprehensive studies of carcinogen and drug metabolism in the human lung, and for a better assessment of cancer risk in selected populations

  3. Epstein-Barr virus receptor expression on human CD8+ (cytotoxic/suppressor) T lymphocytes.

    Science.gov (United States)

    Sauvageau, G; Stocco, R; Kasparian, S; Menezes, J

    1990-02-01

    In 1977 we showed that cells of a human lymphocytic leukaemia-derived T line (Molt-4) have receptors for Epstein-Barr virus (EBV). More recently, EBV-positive human T cell lymphomas have been recognized and human T cell lines containing the EBV genome have been established in vitro. To understand better the interaction of EBV with T cells, we decided to determine first whether human peripheral blood T lymphocytes express receptors for EBV. Using flow cytometry we examined the binding of both lymphocyte-transforming (B95-8) and non-transforming (P3HR-1) strains of EBV to T lymphocyte subpopulations, using a double labelling technique with T cell-specific phycoerythrinated monoclonal antibodies (Leu 2a) and fluoresceinated viral preparation. Our results suggest that, in general, about 50% of the CD8+ (or suppressor/cytotoxic) T cell subpopulation from both EBV-seropositive and -seronegative individuals can bind EBV. EBV receptor expression on these T cells was about 10 and 51 times less than that on Molt-4 and Raji (an EBV receptor-positive B cell line) cells, respectively. The specificity of this binding was demonstrated by the inhibition of attachment of viral preparations preincubated with a monoclonal antibody directed against the viral ligand (gp240/350), and by preincubating these target T cells with unlabelled virus. We were unable to detect EBV-induced antigens in infected T cells, suggesting that, as in Molt-4 cells, virus internalization may not occur in fresh T cells and/or that the virus receptor may not be completely functional. We were also unable to detect C3d (or CR2) receptors on these T cells, or to inhibit virus attachment by treating the targets with an anti-CR2 monoclonal antibody (OKB7), suggesting that the EBV receptor on CD8+ peripheral blood lymphocytes is different from that on B cells. PMID:2155291

  4. Patient-Derived Tumor Xenografts Are Susceptible to Formation of Human Lymphocytic Tumors.

    Science.gov (United States)

    Bondarenko, Gennadiy; Ugolkov, Andrey; Rohan, Stephen; Kulesza, Piotr; Dubrovskyi, Oleksii; Gursel, Demirkan; Mathews, Jeremy; O'Halloran, Thomas V; Wei, Jian J; Mazar, Andrew P

    2015-09-01

    Patient-derived xenograft (PDX) tumor models have emerged as a new approach to evaluate the effects of cancer drugs on patients' personalized tumor grafts enabling to select the best treatment for the cancer patient and providing a new tool for oncology drug developers. Here, we report that human tumors engrafted in immunodeficient mice are susceptible to formation of B-and T-cell PDX tumors. We xenografted human primary and metastatic tumor samples into immunodeficient mice and found that a fraction of PDX tumors generated from patients' samples of breast, colon, pancreatic, bladder and renal cancer were histologically similar to lymphocytic neoplasms. Moreover, we found that the first passage of breast and pancreatic cancer PDX tumors after initial transplantation of the tumor pieces from the same human tumor graft could grow as a lymphocytic tumor in one mouse and as an adenocarcinoma in another mouse. Whereas subcutaneous PDX tumors resembling human adenocarcinoma histology were slow growing and non-metastatic, we found that subcutaneous PDX lymphocytic tumors were fast growing and formed large metastatic lesions in mouse lymph nodes, liver, lungs, and spleen. PDX lymphocytic tumors were comprised of B-cells which were Epstein-Barr virus positive and expressed CD45 and CD20. Because B-cells are typically present in malignant solid tumors, formation of B-cell tumor may evolve in a wide range of PDX tumor models. Although PDX tumor models show great promise in the development of personalized therapy for cancer patients, our results suggest that confidence in any given PDX tumor model requires careful screening of lymphocytic markers. PMID:26476081

  5. Protective Effect of Onion Extract on Bleomycin-Induced Cytotoxicity and Genotoxicity in Human Lymphocytes.

    Science.gov (United States)

    Cho, Yoon Hee; Lee, Joong Won; Woo, Hae Dong; Lee, Sunyeong; Kim, Yang Jee; Lee, Younghyun; Shin, Sangah; Joung, Hyojee; Chung, Hai Won

    2016-02-01

    Following one of the world's largest nuclear accidents, occured at Fukushima, Japan in 2011, a significant scientific effort has focused on minimizing the potential adverse health effects due to radiation exposure. The use of natural dietary antioxidants to reduce the risk of radiation-induced oxidative DNA damage is a simple strategy for minimizing radiation-related cancer rates and improving overall health. The onion is among the richest sources of dietary flavonoids and is an important food for increasing their overall intake. Therefore, we examined the effect of an onion extract on cyto- and geno-toxicity in human lymphocytes treated with bleomycin (BLM), a radiomimetic agent. In addition, we measured the frequency of micronuclei (MN) and DNA damage following treatment with BLM using a cytokinesis-blocked micronucleus assay and a single cell gel electrophoresis assay. We observed a significant increase in cell viability in lymphocytes treated with onion extract then exposed to BLM compared to cells treated with BLM alone. The frequency of BLM induced MN and DNA damage increased in a dose-dependent manner; however, when lymphocytes were pretreated with onion extract (10 and 20 μL/mL), the frequency of BLM-induced MN was decreased at all doses of BLM and DNA damage was decreased at 3 μg/mL of BLM. These results suggest that onion extract may have protective effects against BLM-induced cyto- and genotoxicity in human lymphocytes. PMID:26907305

  6. Protective Effect of Onion Extract on Bleomycin-Induced Cytotoxicity and Genotoxicity in Human Lymphocytes

    Directory of Open Access Journals (Sweden)

    Yoon Hee Cho

    2016-02-01

    Full Text Available Following one of the world’s largest nuclear accidents, occured at Fukushima, Japan in 2011, a significant scientific effort has focused on minimizing the potential adverse health effects due to radiation exposure. The use of natural dietary antioxidants to reduce the risk of radiation-induced oxidative DNA damage is a simple strategy for minimizing radiation-related cancer rates and improving overall health. The onion is among the richest sources of dietary flavonoids and is an important food for increasing their overall intake. Therefore, we examined the effect of an onion extract on cyto- and geno-toxicity in human lymphocytes treated with bleomycin (BLM, a radiomimetic agent. In addition, we measured the frequency of micronuclei (MN and DNA damage following treatment with BLM using a cytokinesis-blocked micronucleus assay and a single cell gel electrophoresis assay. We observed a significant increase in cell viability in lymphocytes treated with onion extract then exposed to BLM compared to cells treated with BLM alone. The frequency of BLM induced MN and DNA damage increased in a dose-dependent manner; however, when lymphocytes were pretreated with onion extract (10 and 20 μL/mL, the frequency of BLM-induced MN was decreased at all doses of BLM and DNA damage was decreased at 3 μg/mL of BLM. These results suggest that onion extract may have protective effects against BLM-induced cyto- and genotoxicity in human lymphocytes.

  7. Changes of the production of lymphokines from γ-irradiated human tonsillar lymphocytes: Pt. 1

    International Nuclear Information System (INIS)

    Human tonsillar lymphocytes were exposed to γ-rays of various doses (0∼40Gy) and stimulated by PHA, then cultured for various periods (24∼96h). The activity of Interleukin 2 (IL 2) in the supernatants was assayed by MTT colorimetric method. The results showed: (A) The activity of IL 2 decreased with irradiation of 2.5Gy, and was maintained at a certain level with 5∼20Gy, and decreased markedly with 40Gy; (B) The activity of IL 2 in the supernatants in 48∼96h incubation showed a constant high level. Both the doses of irradiation and the cultural preiods had no interaction on the changes of the production of IL 2. The results here are different from that in the previous reports in which irradiation can increase the production of IL 2 from human peripheral blood lymphocytes. It is possible that the composition, distribution, function of the functional subsets of T lymphocytes in the tonsils are different from those of peripheral blood lymphocytes, therefore, there is the difference of the radiosensitivity between them

  8. Two small lymphocyte subpopulations in human peripheral blood. I. Purification and surface marker profiles

    DEFF Research Database (Denmark)

    Hokland, M; Hokland, P; Heron, I

    1978-01-01

    By means of simple rosette sedimentation methods two subsets from human peripheral blood lymphocytes have been isolated: (1) (E, Fc)- and (2) (E, Ig)-. The first subset was obtained by centrifuging suspensions of macrophage-depleted PBL in which E and EA rosettes had been allowed to form simultan......By means of simple rosette sedimentation methods two subsets from human peripheral blood lymphocytes have been isolated: (1) (E, Fc)- and (2) (E, Ig)-. The first subset was obtained by centrifuging suspensions of macrophage-depleted PBL in which E and EA rosettes had been allowed to form...... simultaneously. The dominant marker of these E- Fc- cells was surface Ig, and during 4 days of culture this population did not alter its surface markers. Subset 2 was obtained in two ways following rosette centrifugation with AET-treated SRBC and rabbit anti-human Ig-coated autologous RBC. This 'Null cell...

  9. Immune recognition of AIDS virus antigens by human and murine cytotoxic T lymphocytes.

    Science.gov (United States)

    Langlade-Demoyen, P; Michel, F; Hoffenbach, A; Vilmer, E; Dadaglio, G; Garicia-Pons, F; Mayaud, C; Autran, B; Wain-Hobson, S; Plata, F

    1988-09-15

    The CTL response to HIV was analyzed in humans and in mice. By using a novel and strictly autologous lymphocyte culture system, human CTL lines were established with PBL from seropositive asymptomatic donors and from patients suffering from AIDS or presenting AIDS-related complex. CTL from HLA-A2 donors recognize and kill murine P815 mastocytoma cells doubly transfected with the human HLA-A2 gene and the HIV env gene; they also kill HLA-compatible human macrophages infected with HIV. CTL specific for the HIV env Ag were also generated in BALB/c mice by immunization with syngeneic murine cells transfected with the HIV env gene. Human and murine HIV-immune CTL populations belong to the CD8 subset of T lymphocytes and are restricted by class I HLA or H-2 transplantation Ag, respectively, in the recognition of HIV env Ag. The two different experimental systems presented here can be used to study CD8 lymphocyte immunity against HIV. The murine model of CTL immunity offers the additional advantage of avoiding the manipulation of infectious virus isolates.

  10. Physiological variation and adaptability in human populations.

    Science.gov (United States)

    Collins, K J

    1999-01-01

    This review traces some of the developments in population physiology based on contributions to the Annals over the last 25 years. Two broad themes are evident, physiological systems variation and adaptation, and by way of introduction an historical perspective of their relationship within human ecology is explored. Studies of physical fitness and work capacity, and the efforts to create standardized field procedures make up a number of the early papers. Longitudinal studies have provided reliable reference standards for Westernized populations, but are virtually non-existent for primitive groups. The relative importance of phenotypic and genotypic variations in working capacity have yet to be clearly defined. The level of habitual activity during childhood contributes to the development of ventilatory capacity though constitutional influences are of major importance. Variability in strength and motor performance of skeletal muscles are shown to have a direct bearing on aspects of growth, development and biological maturation. Physical and psychological stress in communities have been investigated. These and other studies contribute valuable data on the issue of stress, hypertension and cardiovascular morbidity and mortality. On the theme of human adaptability, high altitude populations, variations in thermal tolerance and adaptations in ageing populations have all received recent investigation. Highland people of all ages have considerably larger lung volumes than coastal dwellers. Haematological, biochemical and pulmonary function show adaptive phenomena that vary in different highland groups. In the tropical biome, more recent work includes the functional consequences of malnutrition, ethnic and cultural differences in work capacity, and the effects of endemic disease on physical performance. Annals of Human Biology papers have more recently contributed to investigations on morphological and physiological changes with human ageing. Though there is a decline in

  11. Anti-neutrophil cytoplasmic antibody-enriched IgG induces adhesion of human T lymphocytes to extracellular matrix proteins.

    Science.gov (United States)

    Tomer, Y; Lider, O; Gilburd, B; Hershkoviz, R; Meroni, P L; Wiik, A; Shoenfeld, Y

    1997-06-01

    Recent studies have shown that anti-neutrophil cytoplasmic antibodies (ANCA) can activate neutrophils to adhere to endothelium, degranulate, and cause endothelial cell injury. These data have lead to the hypothesis that the T cell inflammatory response causing the vasculitis in Wegener's granulomatosis (WG) is secondary to stimulation of neutrophils by ANCA. So far there is no evidence for a direct effect of ANCA on lymphocytes. The present study was designed to examine whether lymphocytes can be directly stimulated by ANCA to adhere to endothelial extracellular matrix (ECM) proteins. Human and mouse ANCA-enriched IgG were tested for their ability to increase adhesion of human T lymphocytes to fibronectin, laminin, and intact ECM. Incubation of human T lymphocytes with human ANCA-enriched IgG increased adhesion of the lymphocytes in a dose-dependent manner to fibronectin, laminin, and intact ECM (the percentage adhesion to intact ECM was 55.7 +/- 3.1 and 45.0 +/- 1.0% for lymphocytes incubated with human IgG containing ANCA or control human IgG, respectively; P = 0.0045). The same induction of adhesion to fibronectin, laminin, and intact ECM was observed when the cells were incubated with the F(ab)2 fragment of ANCA-enriched IgG. Similarly, ANCA-enriched IgG produced in mice increased the adhesion of lymphocytes to fibronectin (the percentage adhesion to fibronectin was 29.7 +/- 4.3 and 16.6 +/- 1.9% for lymphocytes incubated with mouse IgG-ANCA or control mouse IgG, respectively; P = 0.0008). These results may suggest that ANCA can directly stimulate lymphocytes to adhere to endothelial ECM and to induce the vasculitic lesions of WG. It remains to be shown by which mechanisms ANCA stimulate lymphocytes to adhere to ECM. PMID:9175913

  12. Induction of DNA repair synthesis in human monocytes/B-lymphocytes compared with T-lymphocytes after exposure to N-acetoxy-N-acetylaminofluorene and dimethylsulfate in vitro

    DEFF Research Database (Denmark)

    Knudsen, Lisbeth E.; Ryder, L P; Wassermann, K

    1992-01-01

    We have explored the induction of DNA repair synthesis in monocyte/B- and T-lymphocyte enriched cell fractions from 12 different human mononuclear blood cell populations. Unscheduled DNA synthesis was measured in monocyte/B- and T-cells after exposure to the DNA-damaging agents dimethylsulfate (D...

  13. T lymphocytes derived from human cord blood provide effective antitumor immunotherapy against a human tumor

    International Nuclear Information System (INIS)

    Although the graft-versus-tumor (GVT) effect of donor-derived T cells after allogeneic hematopoietic stem cell transplantation has been used as an effective adoptive immunotherapy, the antitumor effects of cord blood (CB) transplantation have not been well studied. We established the animal model by transplantation of CB mononuclear cells and/or tumor cells into NOD/SCID mice. The presence of CB derived T cells in NOD/SCID mice or tumor tissues were determined by flow cytometric and immunohistochemical analysis. The anti-tumor effects of CB derived T cells against tumor was determined by tumor size and weight, and by the cytotoxicity assay and ELISPOT assay of T cells. We found dramatic tumor remission following transfer of CB mononuclear cells into NOD/SCID mice with human cervical tumors with a high infiltration of CD3+ T cells in tumors. NOD/SCID mice that receive neonatal CB transplants have reconstituted T cells with significant antitumor effects against human cervical and lung tumors, with a high infiltration of CD3+ T cells showing dramatic induction of apoptotic cell death. We also confirmed that T cells showed tumor specific antigen cytotoxicity in vitro. In adoptive transfer of CD3+ T cells into mice with pre-established tumors, we observed much higher antitumor effects of HPV-specific T cells by ELISPOT assays. Our results show that CB derived T lymphocytes will be useful for novel immunotherapeutic candidate cells for therapy of several tumors in clinic

  14. Effect of pyrimethamine and sulphadoxine on human lymphocyte proliferation

    DEFF Research Database (Denmark)

    Bygbjerg, I C; Odum, Niels; Theander, T G

    1986-01-01

    The in vitro effect of pyrimethamine (PYR) on human blood mononuclear cells stimulated with phytohaemagglutinin (PHA), pokeweed mitogen (PWM) and purified protein derivative of tuberculin (PPD) was studied by 14C-thymidine incorporation, by cell counting and by total DNA estimation. PYR in concen......The in vitro effect of pyrimethamine (PYR) on human blood mononuclear cells stimulated with phytohaemagglutinin (PHA), pokeweed mitogen (PWM) and purified protein derivative of tuberculin (PPD) was studied by 14C-thymidine incorporation, by cell counting and by total DNA estimation. PYR...

  15. Adaptive Human Control Gains During Precision Grip

    Directory of Open Access Journals (Sweden)

    Erik D. Engeberg

    2013-03-01

    Full Text Available Eight human test subjects attempted to track a desired position trajectory with an instrumented manipulandum (MN. The test subjects used the MN with three different levels of stiffness. A transfer function was developed to represent the human application of a precision grip from the data when the test subjects initially displaced the MN so as to learn the position mapping from the MN onto the display. Another transfer function was formed from the data of the remainder of the experiments, after significant displacement of the MN occurred. Both of these transfer functions accurately modelled the system dynamics for a portion of the experiments, but neither was accurate for the duration of the experiments because the human grip dynamics changed while learning the position mapping. Thus, an adaptive system model was developed to describe the learning process of the human test subjects as they displaced the MN in order to gain knowledge of the position mapping. The adaptive system model was subsequently validated following comparison with the human test subject data. An examination of the average absolute error between the position predicted by the adaptive model and the actual experimental data yielded an overall average error of 0.34mm for all three levels of stiffness.

  16. Is the Oxidative DNA Damage Level of Human Lymphocyte Correlated with the Antioxidant Capacity of Serum or the Base Excision Repair Activity of Lymphocyte?

    Directory of Open Access Journals (Sweden)

    Yi-Chih Tsai

    2013-01-01

    Full Text Available A random screening of human blood samples from 24 individuals of nonsmoker was conducted to examine the correlation between the oxidative DNA damage level of lymphocytes and the antioxidant capacity of serum or the base excision repair (BER activity of lymphocytes. The oxidative DNA damage level was measured with comet assay containing Fpg/Endo III cleavage, and the BER activity was estimated with a modified comet assay including nuclear extract of lymphocytes for enzymatic cleavage. Antioxidant capacity was determined with trolox equivalent antioxidant capacity assay. We found that though the endogenous DNA oxidation levels varied among the individuals, each individual level appeared to be steady for at least 1 month. Our results indicate that the oxidative DNA damage level is insignificantly or weakly correlated with antioxidant capacity or BER activity, respectively. However, lymphocytes from carriers of Helicobacter pylori (HP or Hepatitis B virus (HBV tend to give higher levels of oxidative DNA damage (P<0.05. Though sera of this group of individuals show no particular tendency with reduced antioxidant capacity, the respective BER activities of lymphocytes are lower in average (P<0.05. Thus, reduction of repair activity may be associated with the genotoxic effect of HP or HBV infection.

  17. Signalling detection of DNA damage induced by low doses of ionizing radiation in human lymphocytes

    International Nuclear Information System (INIS)

    gamma-H2AX foci in response to irradiation. Using the methodological tools developed during this thesis we established for the various lymphocyte subsets the relationship between radiation dose and gamma-H2AX foci frequency as well as the kinetics of appearance/disappearance of gamma-H2AX foci. Finally, since no additional samples from patients of known radiosensitivity were available to continue the initial study with the improved protocol, we focused on radiosensitivity in another context: radio-adaptive response. This phenomenon corresponds to a lower cellular response to high dose of ionizing radiation exposure if it is preceded by an exposure to low doses. With the conditions used here we did not observe a radio-adaptive response in terms of gamma-H2AX signalling regardless of the lymphocyte subpopulation studied. However, the translocation rate of pre-irradiated CD4-positive lymphocytes was significantly different when compared to cells only irradiated acutely. This result thus indicates a differential repair of double strand breaks in lymphocytes after a radio-adaptation. (author)

  18. Protective effect of allium sativum ethanol extract on cultured human lymphocytes against electron beam radiation

    International Nuclear Information System (INIS)

    The development of radioprotective agent has been the subject of intense research because exposure to ionizing radiation causes DNA damage which may cause mutation and ultimately leads to cancer, on the other hand radiotherapy has become an integral part in treatment of cancer which uses ionizing radiations like X rays, gamma rays to kill the cancer cells. Amifostine is a well-known radioprotector which is clinically approved. There are many other radioprotectors like cysteine, cystamine, serotine but they are not used because of its normal tissue toxicity. Allium sativum is commonly known as garlic which has already been reported for its medicinal properties. In this study we evaluated radioprotection property of Allium sativum on DNA damage caused by electron beam radiation in cultured human lymphocytes. Allium sativum ethanol extract was used for this study. Cell viability was performed by MTT assay. DNA damage was assessed by comet assay parameters. The cultured lymphocytes were incubated with different concentrations 10, 50 and 100 μg/mL of Allium sativum extracts for 2, 4, 6 and 24 hour time intervals. Treatment of lymphocytes with various concentration of Allium sativum extract resulted in significant decrease in the level of DNA damage (Percentage tail DNA 6%) and increase in cell viability 93% (p>0.05) compare to the radiation control group. Results of this study revealed that Allium sativum protects cultured lymphocytes when exposed to electron beam radiation at its sub lethal dose. (author)

  19. Engineered human embryonic stem cell-derived lymphocytes to study in vivo trafficking and immunotherapy.

    Science.gov (United States)

    Knorr, David A; Bock, Allison; Brentjens, Renier J; Kaufman, Dan S

    2013-07-01

    Human embryonic stem cell (hESC)-derived natural killer (NK) cells are a promising source of antitumor lymphocytes for immunotherapeutics. They also provide a genetically tractable platform well suited for the study of antitumor immunotherapies in preclinical models. We have previously demonstrated the potency of hESC-derived NK cells in vivo. Here we use both bioluminescent and fluorescent imaging to demonstrate trafficking of hESC-derived NK cells to tumors in vivo. Our dual-imaging approach allowed us to more specifically define the kinetics of NK cell trafficking to tumor sites. NK cell persistence and trafficking were further evaluated by flow cytometry and immunohistochemistry. This integrated approach provides a unique system to apply the use of human pluripotent stem cells to study the kinetics and biodistribution of adoptively transferred lymphocytes, advances broadly applicable to the field of immunotherapy.

  20. Antimutagenic effect of aqueous extract from Agaricus brasiliensis on culture of human lymphocytes.

    Science.gov (United States)

    Gameiro, Paula H; Nascimento, José S; Rocha, Beatriz H G; Piana, Clause F B; Santos, Raquel A; Takahashi, Catarina S

    2013-02-01

    The mushroom Agaricus brasiliensis (sun mushroom), native from the southeast of Brazil, is well known by its medicinal properties that include effects on diabetes, cholesterol levels, and osteoporosis. The antimutagenic effects of A. brasiliensis has been investigated recently and revealed some controversial results depending on the temperature by which the A. brasiliensis tea is obtained. In the present study, we evaluated the effect of the A. brasiliensis extract prepared in two different temperatures, 4°C and 25°C, on the doxorubicin-induced DNA strand breaks and chromosomal aberrations (CAs) in human lymphocytes. The results demonstrated that A. brasiliensis was able to reduce the DXR-induced DNA damage in both temperatures; however, the CA test was more sensitive to demonstrate a better reduction when the cells were treated with an extract obtained at 25°C. A. brasiliensis extract obtained in different temperatures exhibited antigenotoxic and anticlastogenic effects in human lymphocytes.

  1. Microgravity simulations with human lymphocytes in the free fall machine and in the random positioning machine

    Science.gov (United States)

    Schwarzenberg, M.; Pippia, P.; Meloni, M. A.; Cossu, G.; Cogoli-Greuter, M.; Cogoli, A.

    1998-01-01

    The purpose of this paper is to present the results obtained in our laboratory with both instruments, the FFM [free fall machine] and the RPM [random positioning machine], to compare them with the data from earlier experiments with human lymphocytes conducted in the FRC [fast rotating clinostat] and in space. Furthermore, the suitability of the FFM and RPM for research in gravitational cell biology is discussed.

  2. Arctigenin from Arctium lappa inhibits interleukin-2 and interferon gene expression in primary human T lymphocytes

    OpenAIRE

    Chang Shwu-Fen; Lee Tzong-Huei; Wang Guei-Jane; Chang Chu-Ting; Tsai Wei-Jern; Lu Shao-Chun; Kuo Yuh-Chi

    2011-01-01

    Abstract Background Arctium lappa (Niubang), a Chinese herbal medicine, is used to treat tissue inflammation. This study investigates the effects of arctigenin (AC), isolated from A. lappa, on anti-CD3/CD28 Ab-stimulated cell proliferation and cytokine gene expression in primary human T lymphocytes. Methods Cell proliferation was determined with enzyme immunoassays and the tritiated thymidine uptake method. Cytokine production and gene expression were analyzed with reverse transcription-polym...

  3. Effects of Moxifloxacin on Human Neutrophil and T-Lymphocyte Functions in Vitro

    OpenAIRE

    Ronald Anderson; Riana Cockeran; Charles Feldman; Theron, Annette J.; Moliehi Potjo

    2010-01-01

    Moxifloxacin is useful in the treatment of respiratory infections, including community-acquired pneumonia, and also shows promise in the treatment of tuberculosis, a clinical setting which necessitates extended administration of this agent. Relatively little is known, however, about the effects of this agent on the antimicrobial and proliferative activities of human neutrophils and T-lymphocytes, respectively. In the current study, we have investigated the effects of moxifloxacin at therapeut...

  4. Expression, processing and transcriptional regulation of granulysin in short-term activated human lymphocytes

    OpenAIRE

    Groscurth Peter; Dumrese Claudia; Sundstrom Hanna; Walch Michael; Latinovic-Golic Sonja; Ziegler Urs

    2007-01-01

    Abstract Background Granulysin, a cytotoxic protein expressed in human natural killer cells and activated T lymphocytes, exhibits cytolytic activity against a variety of intracellular microbes. Expression and transcription have been partially characterised in vitro and four transcripts (NKG5, 519, 520, and 522) were identified. However, only a single protein product of 15 kDa was found, which is subsequently processed to an active 9 kDa protein. Results In this study we investigated generatio...

  5. Fifty cases of human immunodeficiency virus (HIV) infection: immunoultrastructural study of circulating lymphocytes.

    OpenAIRE

    Feremans, W W; Huygen, K.; Menu, R; Farber, C M; de Caluwe, J P; van Vooren, J P; Marcelis, L; Andre, L; Brasseur, M; Bondue, H

    1988-01-01

    The peripheral lymphocytes of 50 cases of human immunodeficiency virus (HIV) infection (13 of acquired immune deficiency syndrome (AIDS), 17 of AIDS related complex (ARC), and 20 healthy carriers) were studied immunoultrastructurally. The prevalence of "tubuloreticular structures" and "tubular confronting cisternae" increased with the progression of the disease. Numerous tubular confronting cisternae were noted in patients presenting with a high serum acid labile alpha-interferon values. The ...

  6. Augmentation of Recipient Adaptive Alloimmunity by Donor Passenger Lymphocytes within the Transplant

    Directory of Open Access Journals (Sweden)

    Ines G. Harper

    2016-05-01

    Full Text Available Chronic rejection of solid organ allografts remains the major cause of transplant failure. Donor-derived tissue-resident lymphocytes are transferred to the recipient during transplantation, but their impact on alloimmunity is unknown. Using mouse cardiac transplant models, we show that graft-versus-host recognition by passenger donor CD4 T cells markedly augments recipient cellular and humoral alloimmunity, resulting in more severe allograft vasculopathy and early graft failure. This augmentation is enhanced when donors were pre-sensitized to the recipient, is dependent upon avoidance of host NK cell recognition, and is partly due to provision of cognate help for allo-specific B cells from donor CD4 T cells recognizing B cell MHC class II in a peptide-degenerate manner. Passenger donor lymphocytes may therefore influence recipient alloimmune responses and represent a therapeutic target in solid organ transplantation.

  7. Human fatal zaire ebola virus infection is associated with an aberrant innate immunity and with massive lymphocyte apoptosis.

    Directory of Open Access Journals (Sweden)

    Nadia Wauquier

    Full Text Available BACKGROUND: Ebolavirus species Zaire (ZEBOV causes highly lethal hemorrhagic fever, resulting in the death of 90% of patients within days. Most information on immune responses to ZEBOV comes from in vitro studies and animal models. The paucity of data on human immune responses to this virus is mainly due to the fact that most outbreaks occur in remote areas. Published studies in this setting, based on small numbers of samples and limited panels of immunological markers, have given somewhat different results. METHODOLOGY/PRINCIPAL FINDINGS: Here, we studied a unique collection of 56 blood samples from 42 nonsurvivors and 14 survivors, obtained during the five outbreaks that occurred between 1996 and 2003 in Gabon and Republic of Congo. Using Luminex technology, we assayed 50 cytokines in all 56 samples and performed phenotypic analyses by flow cytometry. We found that fatal outcome was associated with hypersecretion of numerous proinflammatory cytokines (IL-1β, IL-1RA, IL-6, IL-8, IL-15 and IL-16, chemokines and growth factors (MIP-1α, MIP-1β, MCP-1, M-CSF, MIF, IP-10, GRO-α and eotaxin. Interestingly, no increase of IFNα2 was detected in patients. Furthermore, nonsurvivors were also characterized by very low levels of circulating cytokines produced by T lymphocytes (IL-2, IL-3, IL-4, IL-5, IL-9, IL-13 and by a significant drop of CD3+CD4+ and CD3+CD8+ peripheral cells as well as a high increase in CD95 expression on T lymphocytes. CONCLUSIONS/SIGNIFICANCE: This work, the largest study to be conducted to date in humans, showed that fatal outcome is associated with aberrant innate immune responses and with global suppression of adaptive immunity. The innate immune reaction was characterized by a "cytokine storm," with hypersecretion of numerous proinflammatory cytokines, chemokines and growth factors, and by the noteworthy absence of antiviral IFNα2. Immunosuppression was characterized by very low levels of circulating cytokines produced by

  8. Epistatic adaptive evolution of human color vision.

    Directory of Open Access Journals (Sweden)

    Shozo Yokoyama

    2014-12-01

    Full Text Available Establishing genotype-phenotype relationship is the key to understand the molecular mechanism of phenotypic adaptation. This initial step may be untangled by analyzing appropriate ancestral molecules, but it is a daunting task to recapitulate the evolution of non-additive (epistatic interactions of amino acids and function of a protein separately. To adapt to the ultraviolet (UV-free retinal environment, the short wavelength-sensitive (SWS1 visual pigment in human (human S1 switched from detecting UV to absorbing blue light during the last 90 million years. Mutagenesis experiments of the UV-sensitive pigment in the Boreoeutherian ancestor show that the blue-sensitivity was achieved by seven mutations. The experimental and quantum chemical analyses show that 4,008 of all 5,040 possible evolutionary trajectories are terminated prematurely by containing a dehydrated nonfunctional pigment. Phylogenetic analysis further suggests that human ancestors achieved the blue-sensitivity gradually and almost exclusively by epistasis. When the final stage of spectral tuning of human S1 was underway 45-30 million years ago, the middle and long wavelength-sensitive (MWS/LWS pigments appeared and so-called trichromatic color vision was established by interprotein epistasis. The adaptive evolution of human S1 differs dramatically from orthologous pigments with a major mutational effect used in achieving blue-sensitivity in a fish and several mammalian species and in regaining UV vision in birds. These observations imply that the mechanisms of epistatic interactions must be understood by studying various orthologues in different species that have adapted to various ecological and physiological environments.

  9. Presence of adenovirus species C in infiltrating lymphocytes of human sarcoma.

    Directory of Open Access Journals (Sweden)

    Karin Kosulin

    Full Text Available Human adenoviruses are known to persist in T-lymphocytes of tonsils, adenoids and intestinal tract. The oncogenic potential of different adenovirus types has been widely studied in rodents, in which adenovirus inoculation can induce multiple tumors such as undifferentiated sarcomas, adenocarcinomas and neuroectodermal tumors. However, the oncogenic potential of this virus has never been proven in human subjects. Using a highly sensitive broad-spectrum qRT-PCR, we have screened a set of different human sarcomas including leiomyosarcoma, liposarcoma and gastro intestinal stroma tumors. Primers binding the viral oncogene E1A and the capsid-coding gene Hexon were used to detect the presence of adenovirus DNA in tumor samples. We found that 18% of the tested leiomyosarcomas and 35% of the liposarcomas were positive for the presence of adenovirus DNA, being species C types the most frequently detected adenoviruses. However, only in one sample of the gastro intestinal stroma tumors the virus DNA could be detected. The occurrence of adenovirus in the tumor sections was confirmed by subsequent fluorescence in-situ-hybridization analysis and co-staining with the transcription factor Bcl11b gives evidence for the presence of the virus in infiltrating T-lymphocytes within the tumors. Together these data underline, for the first time, the persistence of adenovirus in T-lymphocytes infiltrated in muscular and fatty tissue tumor samples. If an impaired immune system leads to the viral persistence and reactivation of the virus is involved in additional diseases needs further investigation.

  10. Serum microRNAs as biomarkers of human lymphocyte activation in health and disease.

    Directory of Open Access Journals (Sweden)

    Paola ede Candia

    2014-02-01

    Full Text Available Induction of the adaptive immune system is evaluated mostly by assessment of serum antibody titers and T lymphocyte responses in peripheral blood, although T and B cell activation occurs in lymphoid tissues. In recent years, the release of microRNAs (miRNAs in the extra-cellular environment has been exploited to assess cell functions at distance via measurement of serum miRNAs. Also activated lymphocytes release a large amount of nano-sized vesicles (exosomes, containing miRNA, but there are still few data on whether this phenomenon is reflected in modulation of serum miRNAs. Interestingly, miRNA signatures of CD4+ T cell-derived exosomes are substantially different from intracellular miRNA signatures of the same cells. We have recently identified serum circulating miR-150 as a sensor of general lymphocyte activation and we strongly believe that the identification of miRNAs differentially released by specific CD4+ effector T cell subsets (Th1, Th2, Th17 and Treg may work as serum biomarkers of their elicitation in lymphoid tissues but also in damaged tissues, thus providing pivotal information about the nature of immune responses occurring in health and disease.

  11. Modeled microgravity-induced protein kinase C isoform expression in human lymphocytes

    Science.gov (United States)

    Sundaresan, A.; Risin, D.; Pellis, N. R.

    2004-01-01

    In long-term space travel, the crew is exposed to microgravity and radiation that invoke potential hazards to the immune system. T cell activation is a critical step in the immune response. Receptor-mediated signaling is inhibited in both microgravity and modeled microgravity (MMG) as reflected by diminished DNA synthesis in peripheral blood lymphocytes and their locomotion through gelled type I collagen. Direct activation of protein kinase C (PKC) bypassing cell surface events using the phorbol ester PMA rescues MMG-inhibited lymphocyte activation and locomotion, whereas the calcium ionophore ionomycin had no rescue effect. Thus calcium-independent PKC isoforms may be affected in MMG-induced locomotion inhibition and rescue. Both calcium-dependent isoforms and calcium-independent PKC isoforms were investigated to assess their expression in lymphocytes in 1 g and MMG culture. Human lymphocytes were cultured and harvested at 24, 48, 72, and 96 h, and serial samples were assessed for locomotion by using type I collagen and expression of PKC isoforms. Expression of PKC-alpha, -delta, and -epsilon was assessed by RT-PCR, flow cytometry, and immunoblotting. Results indicated that PKC isoforms delta and epsilon were downregulated by >50% at the transcriptional and translational levels in MMG-cultured lymphocytes compared with 1-g controls. Events upstream of PKC, such as phosphorylation of phospholipase Cgamma in MMG, revealed accumulation of inactive enzyme. Depressed calcium-independent PKC isoforms may be a consequence of an upstream lesion in the signal transduction pathway. The differential response among calcium-dependent and calcium-independent isoforms may actually result from MMG intrusion events earlier than PKC, but after ligand-receptor interaction.

  12. Modulation of human enteric epithelial barrier and ion transport function by Peyer's patch lymphocytes

    Institute of Scientific and Technical Information of China (English)

    Jie Chen; Lai-Ling Tsang; Lok-Sze Ho; Dewi K.Rowlands; Jie-Ying Gao; Chuen-Pei Ng; Yiu-Wa Chung; Hsiao-Chang Chan

    2004-01-01

    AIM: To investigate the role of Peyer′s patch lymphocytes in the regulation of enteric epithelial barrier and ion transport function in homeostasis and host defense.METHODS: Mouse Peyer′s patch lymphocytes were cocultured with human intestinal epithelial cell line Caco-2either in the mixed or separated (isolated but permeable compartments) culture configuration. Barrier and transport functions of the Caco-2 epithelial monolayers were measured with short-circuit current (ISC) technique. Release of cytokines was measured by enzyme-linked immunosorbent assay (ELISA) and cytokine mRNA expression was analyzed by semi-quantitative RT-PCR. Barrier and iontransport functions of both culture conditions following exposure to Shigella lipopolysaccharide (LPS) were also examined.RESULTS: The transepithelial resistance (TER) of the epithelial monolayers co-cultured with Peyer′s patch lymphocytes was maintained whereas that of the Caco-2 monolayers alone significantly decreased after eight days in culture.The forskolin-induced anion secretion, in either absence or presence of LPS, was significantly suppressed in the both co-cultures as compared with the Caco-2 cells alone.Furthermore, only the mixed co-culture condition induced the expression and release of mIL-6 from Peyer′s patch lymphocytes, which could be further enhanced by LPS.However, both co-culture conditions suppressed expression and release of epithelial hIL-8 under the unstimulated conditions, while the treatment with LPS stimulated their hIL-8 expression and release.CONCLUSION: Peyer′s patch lymphocytes may modulate intestinal epithelial barrier and ion transport function in homeostasis and host defense via cell-cell contact and cytokine signaling.

  13. Transformation of human fetal thymus and spleen lymphocytes by human t-cell leukemia virus type Ι

    Directory of Open Access Journals (Sweden)

    Akagi,Tadaatsu

    1985-04-01

    Full Text Available Co-cultivation of human thymus and spleen lymphocytes, which were obtained from 26-week and 27-week fetuses, with a lethally-irradiated human cord T-cell line harboring human T-cell leukemia virus type Ι(HTLV-Ι resultes in the establishment of T-cell lines positive for adult T-cell leukemia-associated antigens and producing HTLV-Ι. These cell lines had the phenotype of a helper/inducer subset of peripheral T-cells as evidenced by the reactivity with monoclonal antibodies to human T-cells.

  14. Time-resolved fluorimetric probing of DNA structure in irradiated human lymphocytes

    International Nuclear Information System (INIS)

    An in situ technique has been developed that detects genomic conformational changes in irradiated human cells. Cells are treated on ice with detergent, mild alkali and ethidium bromide (EB) and the resulting intact nuclei are examined using kinetic spectrofluorimetry. In the nuclei of unirradiated lymphocytes the fluorescence decay profile is tri-exponential with a long-lived component (∼23 ns) attributable to EB intercalated within double-stranded DNA, an intermediate life-time component (∼6 ns) indicative of a loosely bound DNA biomolecular-EB complex, and a short-lived component (∼2 ns) corresponding to unbound EB. Irradiated fresh human lymphocytes show three similar components but their relative contributions are changed. Results from a typical donor, show that after 1 Gy the intermediate component decreased with a concomitant increase in the long-lived component while the short-lived component remained essentially unchanged. Fresh whole blood from healthy donors was irradiated at doses of 0.1-1 Gy, and the samples analyzed with or without post-irradiation incubation at 37 deg. C for 24 h prior to lymphocyte extraction. For doses of 1.0 Gy in the absence of incubation there is good agreement between multiple samples of the same individual, or among the six donors, as compared with the results from irradiated isolated lymphocytes. Whole blood incubation was unreliable but results from one individual at 0.1 and 1.0 Gy were similar to those observed without incubation. Fluorescence lifetime analysis can detect DNA structural/topological damage in irradiated human lymphoid cells, and it may have potential application to in vivo bio-dosimetry and bio-monitoring

  15. Mercuric dichloride induces DNA damage in human salivary gland tissue cells and lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, Katharina; Kroemer, Susanne [University of Regensburg, Regensburg (Germany); Sassen, Andrea [University of Regensburg, Department of Pathology, Regensburg (Germany); Staudenmaier, Rainer [Technical University of Munich, Department of Otorhinolaryngology, Head and Neck Surgery, Munich (Germany); Reichl, Franz-Xaver [University of Munich, Institute of Pharmacology and Toxicology, Munich (Germany); Harreus, Ulrich [University of Munich, Department of Otorhinolaryngology, Head and Neck Surgery, Munich (Germany); Hagen, Rudolf; Kleinsasser, Norbert [University of Wuerzburg, Department of Otorhinolaryngology, Head and Neck Surgery, Wuerzburg (Germany)

    2007-11-15

    Amalgam is still one of the most frequently used dental filling materials. However, the possible adverse effects especially that of the mercuric component have led to continued controversy. Considering that mercury may be released from amalgam fillings into the oral cavity and also reach the circulating blood after absorption and resorption, it eventually may contribute to tumorigenesis in a variety of target cells. The present investigation focuses on genotoxic effects below a cytotoxic dose level of mercuric dichloride (HgCl{sub 2}) in human samples of salivary glands and lymphocytes to elucidate a possible role in tumor initiation. DNA migration due to single strand breaks, alkali labile sites and incomplete excision repair was quantified with the aid of the single cell microgel electrophoresis (Comet) assay. The concepts of Olive Tail Moment, percentage of DNA in the Tail and Tail Length were used as measures of DNA damage. To control for cytotoxic effects, the trypan blue exclusion test was applied. Human samples of the parotid salivary gland and lymphocytes of ten donors were exposed to HgCl{sub 2} concentrations from 1 to 50 {mu}M. N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and dimethyl sulfoxide (DMSO) served as controls. Increasing dose-dependent DNA migration could be demonstrated after exposure to HgCl{sub 2} in cells of the salivary glands and lymphocytes. In both cell types a significant increase in DNA migration could be shown starting from HgCl{sub 2} concentrations of 5 {mu}M in comparison to the negative control. The viability of the cell systems was not affected except at the highest concentration (50 {mu}M) tested. These data indicate genotoxic effects of mercuric dichloride in human salivary glands and lymphocytes at concentrations not leading to cytotoxic effects or cell death. Consequently, a contributory role in oral salivary gland tumor initiation warrants further investigation. (orig.)

  16. A secreted form of the human lymphocyte cell surface molecule CD8 arises from alternative splicing

    Energy Technology Data Exchange (ETDEWEB)

    Giblin, P.; Kavathas, P. (Yale Univ. School of Medicine, New Haven, CT (USA)); Ledbetter, J.A. (Oncogen, Seattle, WA (USA))

    1989-02-01

    The human lymphocyte differentiation antigen CD8 is encoded by a single gene that gives rise to a 33- to 34-kDa glycoprotein expressed on the cell surface as a dimer and in higher molecular mass forms. The authors demonstrate that the mRNA is alternatively spliced so that an exon encoding a transmembrane domain is deleted. This gives rise to a 30-kDa molecule that is secreted and exists primarily as a monomer. mRNA corresponding to both forms is present in peripheral blood lymphocytes, Con A-activated peripheral blood lymphocytes, and three CD8{sup +} T-cell lines, with the membrane form being the major species. However, differences in the ratio of mRNA for membrane CD8 and secreted CD8 exist. In addition, the splicing pattern observed differs from the pattern found for the mouse CD8 gene. This mRNA is also alternatively spliced, but an exon encoding a cytoplasmic region is deleted, giving rise to a cell surface molecule that differs in its cytoplasmic tail from the protein encoded by the longer mRNA. Neither protein is secreted. This is one of the first examples of a different splicing pattern between two homologous mouse and human genes giving rise to very different proteins. This represents one mechanism of generating diversity during speciation.

  17. Cardiomyocyte marker expression in a human lymphocyte cell line using mouse cardiomyocyte extract.

    Science.gov (United States)

    Vojdani, Zahra; Tavakolinejad, Sima; Talaei-Khozani, Tahereh; Esmaeilpour, Tahereh; Rasooli, Manuchehr

    2011-03-01

    Cell transplantation shows potential for the treatment of cardiac diseases. Embryonic stem cells, cord blood and mesenchymal stem cells have been suggested as sources for transplantation therapy. Because of some technical limitations with the use of stem cells, transdifferentiation of fully differentiated cells is a potentially useful alternative. We investigated whether human peripheral blood cells could transdifferentiate into cardiomyocyte. Transdifferentiation was induced in a human B lymphocyte cell line (Raji). Cardiomyocyte extract was prepared from adult mouse cardiomyocytes. The cells were treated with 5-aza-2-deoxycytidine and trichostatin A, permeabilized with streptolysin O, and exposed to the mouse cardiomyocyte extract. They were cultured for 10 days, 3 weeks and 4 weeks. Cardiomyocyte markers were detected with immunohistochemistry and flow cytometry. Immunocytochemistry revealed that some cells expressed myosin heavy chain, α-actinin and cardiac troponin T after 3 and 4 weeks. Flow cytometry confirmed these data. In cells exposed to trichostatin A and 5-aza-2-deoxycytidine and permeabilized in the presence of the cardiomyocyte extract, troponin T expression was seen in 3.53% of the cells and 3.11% of them expressed α-actinin. After exposure to the cardiomyocyte extract, some permeabilized cells adhered to the plate loosely; however, the morphology did not change significantly, and they continued to show a rounded shape after 4 weeks. Our treated lymphocytes expressed cardiomyocyte markers. Our results suggest that lymphocytes may be useful in future research as a source of cells for reprogramming procedures. PMID:21547694

  18. Heterogeneity of the chromosome radiosensitivity of PHA-stimulated human lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Sevan' kaev, A.V.; Obaturov, G.M. (Akademiya Meditsinskikh Nauk SSSR, Obninsk. Nauchno-Issledovatel' skij Inst. Meditsinskoj Radiologii)

    Lymphocytes of peripheric human blood were irradiated up to their stimulation by PHA intermediate (0.35 MeV) and fast (0.85 MeV) neutrons in 0.021-3.4 and 0.022-5.0 gR dose ranges consequently. Irradiation of lymphocytes by /sup 60/Co gamma-quanta was conducted for correlation in 0.05-10 gK dose range. Immediately after irradiation the cells were cultivated with PHA during 50 h. The number of aberrant cells under the neutron effect didn't achieve 1000% and began to decrease at high doses (depending on neutron energy), as opposed to gamma irradiation, when the growth of aberrant cell number decelerated gradually and achieved the level of 100% at 8 gK dose, remaining at this level at 10 gK dose. Analysis of aberration distribution in cells during gamma and neutron irradiation showed the sufficient difference between them. The obtained results testify to heterogeneity of population of PHA-stimulated human lymphocytes with respect to chromosome radiosensitivity.

  19. A secreted form of the human lymphocyte cell surface molecule CD8 arises from alternative splicing

    International Nuclear Information System (INIS)

    The human lymphocyte differentiation antigen CD8 is encoded by a single gene that gives rise to a 33- to 34-kDa glycoprotein expressed on the cell surface as a dimer and in higher molecular mass forms. The authors demonstrate that the mRNA is alternatively spliced so that an exon encoding a transmembrane domain is deleted. This gives rise to a 30-kDa molecule that is secreted and exists primarily as a monomer. mRNA corresponding to both forms is present in peripheral blood lymphocytes, Con A-activated peripheral blood lymphocytes, and three CD8+ T-cell lines, with the membrane form being the major species. However, differences in the ratio of mRNA for membrane CD8 and secreted CD8 exist. In addition, the splicing pattern observed differs from the pattern found for the mouse CD8 gene. This mRNA is also alternatively spliced, but an exon encoding a cytoplasmic region is deleted, giving rise to a cell surface molecule that differs in its cytoplasmic tail from the protein encoded by the longer mRNA. Neither protein is secreted. This is one of the first examples of a different splicing pattern between two homologous mouse and human genes giving rise to very different proteins. This represents one mechanism of generating diversity during speciation

  20. Genotoxic effect of Bothrops snake venoms and isolated toxins on human lymphocyte DNA.

    Science.gov (United States)

    Marcussi, Silvana; Stábeli, Rodrigo G; Santos-Filho, Norival A; Menaldo, Danilo L; Silva Pereira, Luciana L; Zuliani, Juliana P; Calderon, Leonardo A; da Silva, Saulo L; Antunes, Lusânia M Greggi; Soares, Andreimar M

    2013-04-01

    In the present study, micronucleus with cytokinesis blocking and comet assays were used to evaluate the genotoxic potential of Bothrops jararacussu, Bothrops atrox, Bothrops moojeni, Bothrops alternatus (Rhinocerophis alternatus) and Bothrops brazili snake venoms, and also of some isolated toxins (MjTX-I, BthTX-I and II myotoxins, BjussuMP-II metalloprotease, and BatxLAAO l-amino acid oxidase) on human lymphocytes. Significant DNA damages were observed, indicating genotoxic potential after exposure of the lymphocytes to the toxins BthTX-I, II and BatxLAAO compared to untreated and Cisplatin-treated controls, which were able to induce greater formation of micronuclei. B. brazili, B. jararacussu and B. atrox crude venoms also presented genotoxic potential, and the latter two induced DNA breakage 5 times more often than in normal environmental conditions (control without treatment). B. jararacussu venom and its isolated toxins, as well as an LAAO from B. atrox, were able to cause lymphocyte DNA breakage in the comet test with more than 85% damage levels. The DNA damage evaluation allows a widening of the toxic-pharmacological characterization of snake venoms and their toxins and also contributes to the understanding of the mechanisms of action of these molecules in several human pathologies. PMID:23333649

  1. A galactose-inhibitable mitogen for human lymphocytes from the sponge axinella polypoides.

    Science.gov (United States)

    Phillips, S G; Bretting, H; Kabat, E A

    1976-10-01

    Of two galactose-binding hemagglutinins isolated from the sponge Axinella polypoides, axinella I was strongly mitogenic for human peripheral blood lymphocytes, and axinella II was not. Purified T cells responded strongly and B cells weakly to axinella I. Mitogenic response, as monitored by rate of 3H-thymidine incorporation on the third day of culture, was specifically inhibited by Dgalactose, Dfucose, raffinose, or 2-deoxy-D-galactose added within 5 hr of the mitogen. Mitogenic response was correlated with degree of lymphocyte agglutination. The effectiveness of a given sugar in inhibiting mitogenic response to axinella I paralleled its potency in inhibiting precipitation of lectin by blood group substances. If an inhibitory concentration of Dgalactose was add 24 to 40 hr after mitogenic activation, rate of 3H-thymadine uptake at 72 hr was two to twenty times above the rate induced in cultures to which no galactose was added. Dgalactose at a subinhibitory concentration (10mug/ml) enhanced 3H-thymidine incorportion incorporation induced by phytohemagglutinin or Con A, an effect reversible by Dgalactose. These findings suggest that axinella I has tow antagonistic effects on human lymphocytes: a) mitogenic activation and b) depressive activity resulting from depletion of essential galactose moieties.

  2. Influence of exogenous interleukine 2 on the survival curve of human lymphocytes

    International Nuclear Information System (INIS)

    The influence of interleukine 2 (Il-2) has been measured on plating efficiency and on radiosensitivity of peripheral blood lymphocytes originating from 2 different human donors. The endpoint used was a T-cell colony assay. Providing Il-2 leads to an increase of both plating efficiency and survival. The influence of exogenous Il-2 is donor dependent: the lower the level of Il-2 produced by the donor, the higher the influence of the exogenous one on plating efficiency and on radiosensitivity. However, for both donors, the survival curve remains biphasic in the Il-2 assay. Il-2 modifies essentially the initial slope, thus suggesting a relationship between this initial component and the level of Il-2. The hypothesis of 2 different sub-populations is frequently evoked to explain the biphasic shape of the curves. The role of 2 different radio-induced T lymphocyte deaths is discussed as an alternate explanation

  3. X-ray induction of micronuclei in human lymphocyte subpopulations differentiated by immunoperoxidase staining

    International Nuclear Information System (INIS)

    In this report we sought to confirm the radiosensitivity of human peripheral blood lymphocyte subpopulations using a micronucleus assay. Mononucleated cells isolated from peripheral blood were irradiated with X rays. After being cultured for 3 days, cells were fixed and stained using the immunoperoxidase staining technique. Lymphocyte subpopulations were characterized by means of the monoclonal antibodies Leu4 (CD3), Leu2a (CD8), and Leu19 (CD56). Dose-response curves were obtained by scoring the number of micronuclei in binucleated cells that reacted with a specific antibody and were then stained. The dose response of CD8+ (suppressor/cytotoxic) cells was quite similar to that of CD3+ (pan T) cells. In comparison, CD56+ (natural killer) cells were significantly less sensitive, although scorable binucleated CD56+ cells made up less than 4 % of the total number of binucleated cells. (author)

  4. Improvement of techniques for the detection of radio-induced micronuclei in human blood lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Voisin, P.; Paillole, N.

    1995-12-31

    Scoring of micronuclei in cytokinesis-blocked peripheral human lymphocytes, after an accidental overexposure, seems an easier and faster alternative for biological dosimetry than conventional cytogenetics (dicentric chromosomes). Several variations of the cytokinesis-block micronucleus assay have been tested, in order to obtain a sufficient number of micronuclei in bi-nucleated cells by the shortest time possible for operational purposes. The methods differ in the use of hypotonic treatment as well as culture time (48 to 72 h), amount of blood and materials used. We have compared frequencies of bi-nucleated cells and micronuclei in normal lymphocytes and after {gamma}-({sup 60}Co) irradiation in vitro with {sup 60}Co for doses up to 6 Gy. Main results and the final choice of the technique are presented. (authors). 3 refs., 3 figs.

  5. The cytogenetic effects of black tea and green tea on cultured human lymphocytes

    Directory of Open Access Journals (Sweden)

    Halil Erhan Eroğlu

    2011-12-01

    Full Text Available In this study, the cytogenetic effects of black tea and green tea were determined in cultured peripheral blood lymphocytes. Results showed that black tea and green tea induced the mitotic and replication indexes and decreased micronuclei. But these data were not statistically significant for green tea. The effects of black tea on the micronucleus formation and mitotic index were statistically significant. The decrease in micronucleus counts indicated that black tea and green tea had considerable anticlastogenic and antigenotoxic effects as observed in vitro in human lymphocytes. Thus, it could be concluded that tea polyphenols protected the normal cells from genotoxic or carcinogenic agents, which indicated the therapeutic and antioxidative role of catechins, flavonoids or other tea compounds.

  6. Regulation of varicella-zoster virus gene expression in human T lymphocytes.

    OpenAIRE

    Perera, L P; Mosca, J D; Ruyechan, W T; Hay, J

    1992-01-01

    Varicella-zoster virus (VZV), a neurotropic alphaherpesvirus, is the etiologic agent of chicken pox and shingles (zoster) in humans. Using an in vitro transient expression assay, we have evaluated the ability of the putative immediate early VZV genes, ORF4, ORF61, and ORF62 (the analogs of the herpes simplex virus alpha 27, alpha 0, and alpha 4 genes, respectively), to modulate the expression of VZV genes of different putative kinetic classes in a human T lymphocyte cell line. These cells are...

  7. An ATP-activated channel is involved in mitogenic stimulation of human T lymphocytes.

    Science.gov (United States)

    Baricordi, O R; Ferrari, D; Melchiorri, L; Chiozzi, P; Hanau, S; Chiari, E; Rubini, M; Di Virgilio, F

    1996-01-15

    We investigated the effect of pharmacologic modulation of the ATP receptor on intracellular ion changes and proliferative response of human peripheral blood lymphocytes (PBLs) and purified T lymphocytes. Extracellular ATP (ATPe) triggered in these cells an increase in the cytoplasmic Ca2+ concentration ([Ca2+]i) and plasma membrane depolarization. Whereas both Ca2+ release from intracellular stores and influx across the plasma membrane were detected in the whole PBL population, only Ca2+ influx was observed in T cells. In the presence of near physiologic extracellular Na+ concentrations (125 mmol/L), Ca2+ permeability through the ATPe-gated channel was very low, suggesting a higher selectivity for monovalent over divalent cations. The selective P2Z agonist benzoylbenzoic ATP (BzATP) increased [Ca2+]i in the presence but not the absence of extracellular Ca2+ and also caused plasma membrane depolarization. The covalent blocker oxidized ATP (oATP), an inhibitor of P2X and P2Z receptors, prevented Ca2+ influx and plasma membrane depolarization, but had no effect on Ca2+ release from stores. Stimulation with ATPe alone had no significant effects on PBL 3H-thymidine incorporation. On the contrary, ATPe or BzATP had a synergistic effect on DNA synthesis stimulated by selective T-cell mitogens such as phytohemagglutinin, anti-CD3 monoclonal antibody, or allogenic PBLs (mixed lymphocyte cultures). Treatment with oATP inhibited mitogenic stimulation by these receptor-directed agents but not by the combined application of the Ca2+ ionophore ionomycin and phorbol myristate acetate. Interleukin-2 partially relieved inhibition by oATP. These results suggest that human T lymphocytes express a plasma membrane channel gated by ATPe that is involved in mitogenic stimulation. PMID:8555491

  8. Human Adaptive Mechatronics and Human-System Modelling

    OpenAIRE

    Satoshi Suzuki; Hiroshi Igarashi; Harumi Kobayashi; Tetsuya Yasuda; Fumio Harashima

    2013-01-01

    Several topics in projects for mechatronics studies, which are ʹHuman Adaptive Mechatronics (HAM)ʹ and ʹHuman‐System Modelling (HSM)ʹ, are presented in this paper. The main research theme of the HAM project is a design strategy for a new intelligent mechatronics system, which enhances operatorsʹ skills during machine operation. Skill analyses and control system design have been addressed. In the HSM project, human modelling based on hierarchical classification of skills was studied, including...

  9. Lymphocyte trafficking and HIV infection of human lymphoid tissue in a rotating wall vessel bioreactor

    Science.gov (United States)

    Margolis, L. B.; Fitzgerald, W.; Glushakova, S.; Hatfill, S.; Amichay, N.; Baibakov, B.; Zimmerberg, J.

    1997-01-01

    The pathogenesis of HIV infection involves a complex interplay between both the infected and noninfected cells of human lymphoid tissue, the release of free viral particles, the de novo infection of cells, and the recirculatory trafficking of peripheral blood lymphocytes. To develop an in vitro model for studying these various aspects of HIV pathogenesis we have utilized blocks of surgically excised human tonsils and a rotating wall vessel (RWV) cell culture system. Here we show that (1) fragments of the surgically excised human lymphoid tissue remain viable and retain their gross cytoarchitecture for at least 3 weeks when cultured in the RWV system; (2) such lymphoid tissue gradually shows a loss of both T and B cells to the surrounding growth medium; however, this cellular migration is reversible as demonstrated by repopulation of the tissue by labeled cells from the growth medium; (3) this cellular migration may be partially or completely inhibited by embedding the blocks of lymphoid tissue in either a collagen or agarose gel matrix; these embedded tissue blocks retain most of the basic elements of a normal lymphoid cytoarchitecture; and (4) both embedded and nonembedded RWV-cultured blocks of human lymphoid tissue are capable of productive infection by HIV-1 of at least three various strains of different tropism and phenotype, as shown by an increase in both p24 antigen levels and free virus in the culture medium, and by the demonstration of HIV-1 RNA-positive cells inside the tissue identified by in situ hybridization. It is therefore reasonable to suggest that gel-embedded and nonembedded blocks of human lymphoid tissue, cocultured with a suspension of tonsillar lymphocytes in an RWV culture system, constitute a useful model for simulating normal lymphocyte recirculatory traffic and provide a new tool for testing the various aspects of HIV pathogenesis.

  10. Evaluation of genotoxic activity of tenofovir disoproxil fumarate in human peripheral lymphocytes

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    Kubra Kurt

    2016-06-01

    Full Text Available Purpose: Antiretroviral drugs used in the treatment of HIV (Human Immunodeficiency Virus iinfection, treat by preventing the proliferation of HIV in human body. People with HIV have to use this drugs for lifelong because of inability of the drugs to eradicate the viruses. In this study, we investigated the in vitro genotoxic activity of tenofovir disoproxil fumarate one of the antiretroviral drugs, in human peripheral lymphocytes. Material and Methods: The cells were treated with four different concentrations of tenofovir disoproxil fumarate for 24 and 48 hours. The levels of sister chromatid exchanges, chromosomal aberrations, and micronucleus in the cells were examined for the genotoxic activity of tenofovir disoproxil fumarate. Mitotic index, proliferation index, and nucleer division index of treated cells were also determined for the cytotoxic effect of tenofovir disoproxil fumarate. Results: There was no significant differences in the level of sister chromatid exchanges, chromosomal aberrations, and micronucleus in human lyphocytes treated with all concetrations of tenofovir disoproxil fumarate for all treatment period as compared to control group. Similarly, it was observed that treatment of tenofovir disoproxil fumarate did not affect the mitotic index, proliferation index, and nucleer division index values. Conclusion: As a result, in this study, it is demonstrated that tenofovir disoproxil fumarate did not have genotoxic or cytotoxic effect in the human peripheral lymphocytes. [Cukurova Med J 2016; 41(2.000: 229-235

  11. Recognition of lyso-phospholipids by human natural killer T lymphocytes.

    Directory of Open Access Journals (Sweden)

    Lisa M Fox

    2009-10-01

    Full Text Available Natural killer T (NKT cells are a subset of T lymphocytes with potent immunoregulatory properties. Recognition of self-antigens presented by CD1d molecules is an important route of NKT cell activation; however, the molecular identity of specific autoantigens that stimulate human NKT cells remains unclear. Here, we have analyzed human NKT cell recognition of CD1d cellular ligands. The most clearly antigenic species was lyso-phosphatidylcholine (LPC. Diacylated phosphatidylcholine and lyso-phosphoglycerols differing in the chemistry of the head group stimulated only weak responses from human NKT cells. However, lyso-sphingomyelin, which shares the phosphocholine head group of LPC, also activated NKT cells. Antigen-presenting cells pulsed with LPC were capable of stimulating increased cytokine responses by NKT cell clones and by freshly isolated peripheral blood lymphocytes. These results demonstrate that human NKT cells recognize cholinated lyso-phospholipids as antigens presented by CD1d. Since these lyso-phospholipids serve as lipid messengers in normal physiological processes and are present at elevated levels during inflammatory responses, these findings point to a novel link between NKT cells and cellular signaling pathways that are associated with human disease pathophysiology.

  12. A direct radioreceptor assay for human growth hormone in serum using cultured human lymphocytes

    International Nuclear Information System (INIS)

    Lesniak and co-workers have developed a radioreceptor assay (RRA) for hGH by using cultured human lymphocytes containing binding sites highly specific for hGH only. Because of the relatively low affinity constant of the receptors for hGH, the experimental sensitivity of the RRA (3.5ng/ml) was distinctly better than that of the RIA (0.5ng/ml) used. This imposes limitations on the use of the assay when hGH is to be measured in serum from normal individuals - particularly in pediatrics. When, for reasons of sensitivity, relatively large amounts of serum (0.1ml=15.4%) are added to the incubate, ''unspecific displacement'' of labelled hGH occurs. This unspecific displacement could not be avoided completely by modifications of the assay conditions. Experimentally, we were able to show that sera taken at different time intervals from patients without measurable hGH (RIA) exhibit a constant unspecific displacement. Furthermore, standard curves run with different hGH-free (RIA) sera were parallel. Thus, if a series of samples from the same individual were available in which one contained hGH (RIA) below the sensitivity threshold of the RRA, the unspecific displacement could be estimated. Also, for each set of samples, an individual standard curve could be constructed whose slope would be given by the measured standard curve. With this approach, immunoassayable and receptorassayable hGH concentrations were compared in 154 samples from children. The overall RRA/RIA ratio (0.76) was below unity (p<0.05); after injection of hGH the ratio was indistinguishable from unity. (author)

  13. Lymphocyte proliferation in old and young humans as measured by flow cytometry: effect of 3H-thymidine on cell cycle kinetics

    International Nuclear Information System (INIS)

    We have compared the proliferation of lymphocytes from old and young humans in response to PHA using flow cytometry. Our results suggest that lymphocytes from old persons are more sensitive to 3H-induced damage than lymphocytes from young persons. This difference in sensitivity, however, does not totally account for the observed differences in 3H-Tdr incorporation by lymphocytes from young and old donors. We have observed, using flow cytometry that fewer lymphocytes from old donors respond to stimulation by PHA. Those lymphocytes which do respond, however, traverse the cell cycle at comparable rates to responding lymphocytes from young donors. Perhaps the most intriguing and unexpected finding is the increased heterogeneity of DNA content in lymphocytes from old donors as evidenced by an increase in the coefficient of variation of DNA content. An excess or shortage of DNA might contribute to the lower level of response to PHA observed in lymphocyte cultures from old donors

  14. The Biological Efficiency of the Petten Research Reactor Beam on Human Lymphocytes (Methodological Approach)

    International Nuclear Information System (INIS)

    In this paper we present preliminary results of examination of the biological efficiency of the Petten Research Reactor mixed beam with respect to 250 kV X-rays for the induction of DNA damage and chromosomal aberrations in human lymphocytes. Human blood samples or isolated lymphocytes were irradiated by the beam from Research Reactor in ECN Petten, Netherlands and dose response relationships for the level of damage induced were investigated. In order to check any enhancement effect due to the process of boron neutron capture, chemical pretreatment with boric acid or mercaptoborane (containing boron-10 ions) was done. The estimation of the DNA damage was done with the use of a single cell gel-electrophoresis method (SCGE), to asses the frequency of chromosomal aberrations culturing of lymphocytes for the evaluation of cytogenetic damage was performed. Abnormal behavior of blood samples during a culture procedure and abnormally low metaphases frequency was noticed. During the analysis of DNA damage by SCGE assay we have also found the abnormalities in shapes and brightness of investigated comets. Part of the studied lymphocytes was bigger than others and had much bigger fraction of the DNA in tail. Very poor dose response relationship was observed in those results. From this reason, our paper presents the methodological approach and discussion of the results obtained and also studies on the parameters reflecting the level of the DNA in human lymphocytes. In order to eliminate outstanding comets (fluffy) we measured for all our results the relation of the fraction of DNA in tail to the length of the comet tail. The value of this ratio usually fluctuated in range of 0.1 to 0.70. For the fluffy comets mentioned before the tDNA/TL ratio was generally about 0.9, or even more than 1.0 that means that the percentage of fraction of DNA in tail was higher than in usually seen comets with such a tail length. After analysis of distribution of frequency cells with various t

  15. Human peripheral blood lymphocytes for the analysis of chromosome aberrations in mutagen tests

    International Nuclear Information System (INIS)

    Studies on exposed individuals, and on cultured cells, have shown that the human peripheral blood lymphocyte is an extremely sensitive indicator of both in vivo and in vitro induced chromosome structural change. These changes in chromosome structure offer readily scored morphological evidence of damage to the genetic material. Although problems exist in the extrapolation from in vitro results to the in vivo situation, the lymphocyte offers several advantages as a test system. The types of chromosome damage which can be cytologically distinguished at metaphase can be divided into two main groups: chromosome type and chromatid type. The circulating lymphocyte is in the G/sub 0/ or G/sub 1/ phase of mitosis and exposure to ionising radiations and certain other mutagenic agents during this stage produces chromosome-type damage where the unit of breakage and reunion is the whole chromosome (i.e. both chromatids at the same locus). However, cells exposed to these agents while in the S or G/sub 2/ stages of the cell cycle, after the chromosome has divided into two sister chromatids, yield chromatid-type aberrations and only the single chromatid is involved in breakage or exchange. Other agents (e.g. some of the alkylating agents) will usually produce only chromatid-type aberrations in cells in cycle although the cells are exposed to the mutagen whilst in G/sub 1/

  16. Lymphocyte subsets in human immunodeficiency virus-unexposed Brazilian individuals from birth to adulthood

    Directory of Open Access Journals (Sweden)

    Maria Isabel de Moraes-Pinto

    2014-12-01

    Full Text Available Ethnic origin, genetics, gender and environmental factors have been shown to influence some immunologic indices, so that development of reference values for populations of different backgrounds may be necessary. We have determined the distribution of lymphocyte subsets in healthy Brazilian individuals from birth to adulthood. Lymphocyte subsets were determined using four-colour cytometry in a cross-sectional study of 463 human immunodeficiency virus-unexposed children and adults from birth through 49 years of age. Lymphocyte subsets varied according to age, as previously observed in other studies. However, total CD4+ T cell numbers were lower than what was described in the Pediatric AIDS Clinical Trials Group P1009 (PACTG P1009, which assessed an American population of predominantly African and Hispanic backgrounds until the 12-18 year age range, when values were comparable. Naïve percentages and absolute values of CD8+ T cells, as assessed by CD45RA expression, were also lower than the PACTG P1009 data for all analysed age ranges. CD38 expression on both CD4+ and CD8+ T cells was lower than the PACTG P1009 values, with a widening gap between the two studies at older age ranges. Different patterns of cell differentiation seem to occur in different settings and may have characteristic expression within each population.

  17. The effect of x-ray induced mitotic delay on chromosome aberration yields in human lymphocytes

    International Nuclear Information System (INIS)

    The extent to which X-ray induced mitotic delay at 150 and 400 rad influences chromosome aberration yields was examined in human peripheral blood lymphocytes. The dicentric was used as a marker and aberration yields were obtained for mixed cultures prepared from equal numbers of normal and irradiated cells. The cultures were terminated following incubation times of 36-120 h. Greater mitotic delay of the order of a few hours was observed at the higher dose. However most reduction in the numbers of lymphocytes arriving at metaphase by 48 h may be ascribed to interphase death of failure to transform. Analysis of the dicentric distributions which were expected to follow Poisson statistics indicated that cells containing dicentrics were delayed relative to irradiated but aberration-free cells. Cells with one dicentric moved more easily through the first cell cycle than cells containing two dicentrics. Following accidental partial body irradiation, selection in culture favouring the unirradiated lymphocytes does not distort the aberration yield sufficiently to warrant incubation times in excess of the standard 48-52 h

  18. In vitro cytotoxic, genotoxic and antioxidant/oxidant effects of guaiazulene on human lymphocytes

    Directory of Open Access Journals (Sweden)

    Başak Toğar

    2015-02-01

    Full Text Available The aim of this study was to evaluate for the cytotoxicity, genotoxicity and antioxidant/oxidant activity of GYZ on human peripheral blood lymphocytes (PBLs. Guaiazulene (GYZ was added into culture tubes at various concentrations (0-400 µg/mL-1. Cytotoxicity against the human lymphocytes cultures was examined by lactate dehydrogenase (LDH release assay. The proliferative response was estimated by 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT assay. Antioxidant/oxidant activity was evaluated by measuring the total oxidant status (TOS and total antioxidant capacity (TAC levels. Micronucleus (MN and chromosomal aberration (CA tests were used in genotoxicity studies. The results showed that GYZ caused cytotoxicity in the PBLs at high concentrations, but TOS level were not affected, while the level of TAC was significantly increased. GYZ also did not induce chromosomal aberrations when compared to that of the control group. Results this study clearly revealed that GYZ was not genotoxic and also increased the capacity of the antioxidant in the culture of human PBL cells. This report is first report on the impact of GYZ on human PBL cells.

  19. Early B lymphocyte development: Similarities and differences in human and mouse

    Institute of Scientific and Technical Information of China (English)

    Michiko; Ichii; Kenji; Oritani; Yuzuru; Kanakura

    2014-01-01

    B lymphocytes differentiate from hematopoietic stem cells through a series of distinct stages. Early B cell development proceeds in bone marrow until immature B cells migrate out to secondary lymphoid tissues, such as a spleen and lymph nodes, after completion of immunoglobulin heavy and light chain rearrangement. Although the information about the regulation by numerous factors, including signaling molecules, transcription factors, epigenetic changes and the microenvironment, could provide the clinical application, our knowledge on human B lymphopoiesis is limited. However, with great methodological advances, significant progress for understanding B lymphopoiesis both in human and mouse has been made. In this review, we summarize the experimental models for studies about human adult B lymphopoiesis, and the role of microenvironment and signaling molecules, such as cytokines, transforming growth factor-β superfamily, Wnt family and Notch family, with point-by-point comparison between human and mouse.

  20. Evaluation of the clastogenicity and anticlastogenicity of the carotenoid bixin in human lymphocyte cultures.

    Science.gov (United States)

    Antunes, Lusânia M Greggi; Pascoal, Lívia M; Bianchi, Maria de Lourdes P; Dias, Francisca L

    2005-08-01

    Carotenoids are regarded as effective antioxidants, antimutagenic and anticarcinogenic agents. Annatto, a red-yellow extract obtained from seeds of Bixa orellana L. is a mixture of several carotenoids and one of them bixin (BXN), is known as its major coloring compound. Studies on BXN clastogenicity and anticlastogenicity in cultured human lymphocytes have not been reported so far. Therefore, the present study was undertaken to investigate the ability of BXN to induce chromosomal aberrations in human lymphocytes in vitro and to examine the possible anticlastogenic effect of this carotenoid in chromosomal damage induced by the clastogen cisplatin (cDDP). Human blood samples were obtained from six healthy, non-smoking volunteers; two females and four males aged 18-35 years. The concentrations of BXN (1.0; 2.5; 5.0 or 10 microg/mL) tested in combination with cDDP were established on the basis of mitotic index (MI) measurements. The data showed that BXN was not cytotoxic or clastogenic, when compared to untreated control. A marked decrease in the MI values compared to the untreated control and an increased percentage of aberrant metaphases was seen in all cultures treated with cDDP. The carotenoid efficiency in reducing the inhibitory effect of cDDP on lymphocyte MI is concentration-dependent. Cultures simultaneously treated with BXN and cDDP showed a statistically significant reduction in total chromosomal aberrations and aberrant metaphases. In our experiments, BXN may have acted as an antioxidant by intercepting free radicals generated by cDDP. The data obtained in the present study suggest that dietary carotenoids may act as protective agents against clastogenic effects of antitumor agents. However, extensive studies are necessary to elucidate the mechanism of action of BXN before its therapeutic use. PMID:15949968

  1. p53 mutations in human lymphoid malignancies: association with Burkitt lymphoma and chronic lymphocytic leukemia.

    OpenAIRE

    Gaidano, G; Ballerini, P.; Gong, J. Z.; Inghirami, G.; Neri, A.; Newcomb, E W; Magrath, I. T.; Knowles, D M; Dalla-Favera, R

    1991-01-01

    We have investigated the frequency of p53 mutations in B- and T-cell human lymphoid malignancies, including acute lymphoblastic leukemia, the major subtypes of non-Hodgkin lymphoma, and chronic lymphocytic leukemia. p53 exons 5-9 were studied by using genomic DNA from 197 primary tumors and 27 cell lines by single-strand conformation polymorphism analysis and by direct sequencing of PCR-amplified fragments. Mutations were found associated with (i) Burkitt lymphoma (9/27 biopsies; 17/27 cell l...

  2. Protective effect of red wine on the frequency of micronuclei in human lymphocytes irradiated in vitro

    International Nuclear Information System (INIS)

    The present investigation was undertaken to study the effect of red wines 'Cabernet Sauvignon' on the micronuclei formation in human lymphocytes. Blood samples of healthy volunteers were irratiated in vitro using 60 Co as a source of radiation, dose of 2Gy. Irradiated samples, as well as unirradiated controls, were treated with concentrations of red wine ranged from 100-500 ml/2x106 cells. Obtained results demonstrated significant decrease of the micronuclei frequency (t=9.14; p0.05) in treated samples versus untreated controls. The results of our study demonstrated radioprotective effect of red wine

  3. Differential human immunodeficiency virus expression in CD4+ cloned lymphocytes: from viral latency to replication.

    Science.gov (United States)

    Chapel, A; Bensussan, A; Vilmer, E; Dormont, D

    1992-06-01

    By using cloning methodology, 13 CD4+, CD8-, CD45RO+, and CD29+ clones, isolated from human immunodeficiency virus (HIV)-negative donors, have been characterized and tested regarding their susceptibility to two strains of HIV type 1 (HIV-1). Infected clones possess integrated provirus. Only six are able to replicate HIV-1, while seven may normally grow without cytopathic effect and without viral replication. These results argue that all CD4+ lymphocyte clones may be infectable but that a heterogeneity exists regarding their abilities to replicate HIV-1.

  4. Interference study on the free calcium in the human peripheral lymphocyte by acrylamide

    Institute of Scientific and Technical Information of China (English)

    Hai Yan Wang; Chun Gui Zhao; Ye Hong Zhou; Shao Min Shuang; Chuan Dong

    2008-01-01

    The role of acrylamide on the human peripheral lymphocytes was studied by laser scanning confocal microscopy technique and fluo-3. The calibration value of the apparent dissociation constant (Kd) of the fluo-3-Ca2+ complex was obtained as 4.83×10-7mol/L. Acrylamide (<54μg/mL) evoked a rise in free intracellular calcium concentration [Ca2+]I, in a dose dependent manner. Acrylamide induced the increase of [Ca+2]I was discussed in detail.

  5. Immature dendritic cells generated from cryopreserved human monocytes show impaired ability to respond to LPS and to induce allogeneic lymphocyte proliferation.

    Directory of Open Access Journals (Sweden)

    Guilherme Ferreira Silveira

    Full Text Available Dendritic cells play a key role in the immune system, in the sensing of foreign antigens and triggering of an adaptive immune response. Cryopreservation of human monocytes was investigated to understand its effect on differentiation into immature monocyte-derived dendritic cells (imdDCs, the response to inflammatory stimuli and the ability to induce allogeneic lymphocyte proliferation. Cryopreserved (crp-monocytes were able to differentiate into imdDCs, albeit to a lesser extent than freshly (frh-obtained monocytes. Furthermore, crp-imdDCs had lower rates of maturation and cytokine/chemokine secretion in response to LPS than frh-imdDCs. Lower expression of Toll-like receptor 4 (at 24 and 48 h and higher susceptibility to apoptosis in crp-imdDCs than in fresh cells would account for the impaired maturation and cytokine/chemokine secretion observed. A mixed leukocyte reaction showed that lymphocyte proliferation was lower with crp-imdDCs than with frh-imdDCs. These findings suggested that the source of monocytes used to generate human imdDCs could influence the accuracy of results observed in studies of the immune response to pathogens, lymphocyte activation, vaccination and antigen sensing. It is not always possible to work with freshly isolated monocytes but the possible effects of freezing/thawing on the biology and responsiveness of imdDCs should be taken into account.

  6. Genotoxicity evaluation of drinking water sources in human peripheral blood lymphocytes using the comet assay

    Institute of Scientific and Technical Information of China (English)

    WU Yulin; CHEN Haigang; LI Zhaoli; SUN Liwei; QU Mengmeng; LI Mei; KONG Zhiming

    2008-01-01

    The potential harm of organic pollutants in drinking water to human health is widely focused on in the world; more and more pollutants with genotoxic substances are released into the aquatic environment. Water source samples were collected from 7 different localities of Nanjing City. The potential genotoxicity of organic extracts from drinking water sources were investigated by means of the comet assay in human peripheral lymphocytes. The results showed that all the organic extracts from all the water source samples could induce DNA damages of human peripheral blood lymphocytes at different levels. A significant difference (P < 0.01) was observed when compared with the solvent control. The DNA damage increased with the increase of the dosage of the original water source. Significant differences of DNA damage were observed in different drinking water sources, as shown by the multiple comparisons analysis at the dosage of 100×; the degree of DNA damage treated by Hushu waterworks (at town level) was the most serious, the arbitrary units (AU) was 141.62±6.96, however, that of Shangyuanmen waterworks (at city level) was only 109.64±2.97. The analysis also revealed that the genotoxicity of town's water sources was higher than that of the city. The results demonstrated that the comet assay can be successfully applied to the genotoxicity monitoring programs of drinking water sources.

  7. Assessment of individual radiosensitivity in human lymphocytes using micronucleus and microgel electrophoresis Comet assays

    International Nuclear Information System (INIS)

    Background and purpose: Individual radiosensitivity is an inherent characteristic, associated with an increased reaction to ionizing radiation on the human body. Individuals show marked differences in radiation sensitivity, which has consequences in the fields of both radiation protection and radiation therapy. It is suggested that DNA repair mechanisms are involved. Consequently, the characterization of DNA repair in lymphocytes through cytokinesis blocked micronucleus (MN) and alkaline single-cell microgel electrophoresis (comet) assays could be suitable approaches to evaluate individual radiosensitivity in vitro. The amins of this study were: 1) to assess the in vitro radisensitivity of peripheral blood lymphocytes from two with the observed clinical response and 2) to test the predictive potential of both techniques. Materials and methods: 38 cancer patients receiving radiation therapy were enrolled in this study. The tumor sites were: head and neck (n=25) and cervic (n=13). 19 pateints were evaluated prior, mid-way and on completion of treatment (prospective group) and 19 patients were evaluated about 2-480 month after radiotherapy (retrospective group). Cytogenetic data from the prospective group were analyzed using a mathematical model to evaluate the attenuation of the cytogenetic effect as a function of the time between a single exposure and blood sampling, estimating a cytogentic recovery factor k. In the retrospective group, blood samples were irradiated in vitro with 0 (control) or 2 Gy and evaluated using MN test. Cytogenetic data were analyzed comparing expected MN frequencies (calibration curve from health donors) with values observed after in vitro irradiation. One over-reactor ad patients that did not develop late effects were also evaluated through comet assay. DNA damage and repair capacity were quantified by the Olive tail moment. Lymphocytes of health individuals were used as reference sample. In the prospective evaluation, factor K correlated

  8. Assessment of individual radiosensitivity in human lymphocytes using micronucleus and microgel electrophoresis Comet assays

    Energy Technology Data Exchange (ETDEWEB)

    Giorgio, M. di; Sardi, M.; Busto, M.; Vallerga, M.; Taja, M.; Mairal, I.

    2004-07-01

    Background and purpose: Individual radiosensitivity is an inherent characteristic, associated with an increased reaction to ionizing radiation on the human body. Individuals show marked differences in radiation sensitivity, which has consequences in the fields of both radiation protection and radiation therapy. It is suggested that DNA repair mechanisms are involved. Consequently, the characterization of DNA repair in lymphocytes through cytokinesis blocked micronucleus (MN) and alkaline single-cell microgel electrophoresis (comet) assays could be suitable approaches to evaluate individual radiosensitivity in vitro. The amins of this study were: 1) to assess the in vitro radisensitivity of peripheral blood lymphocytes from two with the observed clinical response and 2) to test the predictive potential of both techniques. Materials and methods: 38 cancer patients receiving radiation therapy were enrolled in this study. The tumor sites were: head and neck (n=25) and cervic (n=13). 19 pateints were evaluated prior, mid-way and on completion of treatment (prospective group) and 19 patients were evaluated about 2-480 month after radiotherapy (retrospective group). Cytogenetic data from the prospective group were analyzed using a mathematical model to evaluate the attenuation of the cytogenetic effect as a function of the time between a single exposure and blood sampling, estimating a cytogentic recovery factor k. In the retrospective group, blood samples were irradiated in vitro with 0 (control) or 2 Gy and evaluated using MN test. Cytogenetic data were analyzed comparing expected MN frequencies (calibration curve from health donors) with values observed after in vitro irradiation. One over-reactor ad patients that did not develop late effects were also evaluated through comet assay. DNA damage and repair capacity were quantified by the Olive tail moment. Lymphocytes of health individuals were used as reference sample. In the prospective evaluation, factor K correlated

  9. CCR4 versus CCR10 in human cutaneous TH lymphocyte trafficking.

    Science.gov (United States)

    Soler, Dulce; Humphreys, Tricia L; Spinola, Stanley M; Campbell, James J

    2003-03-01

    The chemokine receptors (CCRs) CCR4 and CCR10, and the cutaneous lymphocyte antigen (CLA), have each been proposed as critical mediators of skin-specific TH lymphocyte homing in mice and humans. CLA initiates skin homing by mediating E-selectin-dependent tethering and rolling within cutaneous venules, but the specific roles of CCR4 and CCR10 are unclear. We have generated an antihuman CCR10 monoclonal antibody (mAb; 1B5) to illuminate the individual contributions of these molecules. This mAb allows us to compare CCR10, CCR4, and CLA expression within human TH populations. The mAb 1B5 recognizes functional CCR10 expression, as chemotactic responsiveness to cutaneous T-cell-attracting chemokine (CTACK)/CCL27 (a CCR10 ligand) parallels the staining of TH subsets. We find CCR10 expressed by only a minority (approximately 30%) of blood-borne, skin-homing (CLA+/CCR4+) TH cells. However, essentially all members of the relatively small "effector" (CLA+/CCR4+/CD27-/CCR7-) skin-homing TH population express CCR10. Most skin-infiltrating lymphocytes in allergic delayed-type hypersensitivity (DTH) and bacterial chancroid skin lesions express both CCR4 and CLA, but only about 10% express CCR10. This suggests for the 2 models of TH skin homing studied here that CCR10+ TH cells have no advantage over other CLA+/CCR4+ TH cells in homing to cutaneous sites. We conclude that the skin-homing TH compartment is itself divided into distinct subpopulations, the smaller of which expresses both CCR4 and CCR10, and the larger of which expresses only CCR4. Thus, CCR10 is unlikely to be necessary for cutaneous homing of TH cells in the models studied here. CCR10 may instead play a role in the movement of specialized "effector" cutaneous TH cells to and/or within epidermal microenvironments.

  10. Interaction of Epstein-Barr virus (EBV) with human B-lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Klein, George, E-mail: Georg.Klein@ki.se [Karolinska Institutet, Department of Microbiology, Tumor and Cell Biology (MTC), Box 280, S171 77 Stockholm (Sweden); Klein, Eva; Kashuba, Elena [Karolinska Institutet, Department of Microbiology, Tumor and Cell Biology (MTC), Box 280, S171 77 Stockholm (Sweden)

    2010-05-21

    Epstein-Barr virus, EBV, and humans have a common history that reaches back to our primate ancestors. The virus co-evolved with man and has established a largely harmless and highly complex co-existence. It is carried as silent infection by almost all human adults. A serendipitous discovery established that it is the causative agent of infectious mononucleosis. Still, EBV became known first in 1964, in a rare, geographically prevalent malignant lymphoma of B-cell origin, Burkitt lymphoma BL. Its association with a malignancy prompted intensive studies and its capacity to immortalize B-lymphocytes in vitro was soon demonstrated. Consequently EBV was classified therefore as a potentially tumorigenic virus. Despite of this property however, the virus carrier state itself does not lead to malignancies because the transformed cells are recognized by the immune response. Consequently the EBV induced proliferation of EBV carrying B-lymphocytes is manifested only under immunosuppressive conditions. The expression of EBV encoded genes is regulated by the cell phenotype. The virus genome can be found in malignancies originating from cell types other than the B-lymphocyte. Even in the EBV infected B-cell, the direct transforming capacity is restricted to a defined window of differentiation. A complex interaction between virally encoded proteins and B-cell specific cellular proteins constitute the proliferation inducing program. In this short review we touch upon aspects which are the subject of our present work. We describe the mechanisms of some of the functional interactions between EBV encoded and cellular proteins that determine the phenotype of latently infected B-cells. The growth promoting EBV encoded genes are not expressed in the virus carrying BL cells. Still, EBV seems to contribute to the etiology of this tumor by modifying events that influence cell survival and proliferation. We describe a possible growth promoting mechanism in the genesis of Burkitt lymphoma

  11. The potent oncogene NPM-ALK mediates malignant transformation of normal human CD4(+) T lymphocytes.

    Science.gov (United States)

    Zhang, Qian; Wei, Fang; Wang, Hong Yi; Liu, Xiaobin; Roy, Darshan; Xiong, Qun-Bin; Jiang, Shuguang; Medvec, Andrew; Danet-Desnoyers, Gwenn; Watt, Christopher; Tomczak, Ewa; Kalos, Michael; Riley, James L; Wasik, Mariusz A

    2013-12-01

    With this study we have demonstrated that in vitro transduction of normal human CD4(+) T lymphocytes with NPM-ALK results in their malignant transformation. The transformed cells become immortalized and display morphology and immunophenotype characteristic of patient-derived anaplastic large-cell lymphomas. These unique features, which are strictly dependent on NPM-ALK activity and expression, include perpetual cell growth, proliferation, and survival; activation of the key signal transduction pathways STAT3 and mTORC1; and expression of CD30 (the hallmark of anaplastic large-cell lymphoma) and of immunosuppressive cytokine IL-10 and cell-surface protein PD-L1/CD274. Implantation of NPM-ALK-transformed CD4(+) T lymphocytes into immunodeficient mice resulted in formation of tumors indistinguishable from patients' anaplastic large-cell lymphomas. Our findings demonstrate that the key aspects of human carcinogenesis closely recapitulating the features of the native tumors can be faithfully reproduced in vitro when an appropriate oncogene is used to transform its natural target cells; this in turn points to the fundamental role in malignant cell transformation of potent oncogenes expressed in the relevant target cells. Such transformed cells should permit study of the early stages of carcinogenesis, and in particular the initial oncogene-host cell interactions. This experimental design could also be useful for studies of the effects of early therapeutic intervention and likely also the mechanisms of malignant progression.

  12. Grapevine fruit extract protects against radiation-induced oxidative stress and apoptosis in human lymphocyte

    International Nuclear Information System (INIS)

    Ionizing radiation (IR) causes oxidative stress through overwhelming generation of reactive oxygen species (ROS) in the living cells leading the oxidative damage further to biomolecules. Grapevine (Vitis vinifera L.) posses several bioactive phytochemicals and is the richest source of antioxidants. In this study, we investigated V. vinifera for its phytochemical content, enzymes profile and, ROS-and oxidant-scavenging activities. We have also studied the fruit extract of four different grapevine viz., Thompson seedless, Flame seedless, Kishmish chorni and Red globe for their radioprotective actions in human lymphocytes. The activities of ascorbic acid oxidase and catalase significantly (P < 0.01) differed among extracts within the same cultivar, while that of peroxidase and polyphenol oxidase did not differ significantly. The superoxide radical-scavenging activity was higher in the seed as compared to the skin or pulp of the same cultivar. Pretreatment with grape extracts attenuated the oxidative stress induced by 4 Gy γ-radiation in human lymphocytes in vitro. Further, γ-radiation-induced increase in caspase 3/7 activity was significantly attenuated by grape extracts. These results suggest that grape extract serve as a potential source of natural antioxidants against the IR-induced oxidative stress and also inhibit apoptosis. Furthermore, the protective action of grape depends on the source of extract (seed, skin or pulp) and type of the cultivars. (author)

  13. Studies on chromosome aberrations induced in human lymphocytes by very low-dose exposure to tritium

    International Nuclear Information System (INIS)

    Assessment of potential hazard from environmental tritium to man becomes very important with increasing the development of nuclear-power industry. However, little data are available as to the determination on the genetic effect of tritium especially at the low levels. The object of the present study is to obtain quantitative data for chromosome aberrations in human lymphocytes, as an indicator for genetic risk estimation, induced by tritium at very low dose levels. Leukocyte cultures of human peripheral blood were chronically exposed for 48h to tritiated water and 3H-thymidine using a wide range of tritium doses, and aberrations in lymphocyte chromosomes at the first metaphases were examined. In the experimental conditions, the types of aberrations induced by radiation emitted from both tritiated water and 3H-thymidine were mostly chromatid types, such as chromatid gaps and deletions. The dose-response relations for chromatid breaks per cell exhibited unusual dose-dependency in both cases. It was demonstrated that at higher dose range the yields of chromatid breaks increased linearly with dose, while those at lower dose range were significantly higher than would be expected by a downward extraporation from the linear relation. Partial-hit or partial-target kinetics events appeared at very low dose exposure. (author)

  14. Evaluation of the DNA damaging effects of amitraz on human lymphocytes in the Comet assay

    Indian Academy of Sciences (India)

    Milena Radakovic; Jevrosima Stevanovic; Ninoslav Djelic; Nada Lakic; Jelena Knezevic-Vukcevic; Branka Vukovic-Gacic; Zoran Stanimirovic

    2013-03-01

    Amitraz is formamidine pesticide widely used as insecticide and acaricide. In veterinary medicine, amitraz has important uses against ticks, mites and lice on animals. Also, amitraz is used in apiculture to control Varroa destructor. It this study, the alkaline Comet assay was used to evaluate DNA damaging effects of amitraz in human lymphocytes. Isolated human lymphocytes were incubated with varying concentrations of amitraz (0.035, 0.35, 3.5, 35 and 350 g/mL). The Comet assay demonstrated that all concentrations of amitraz caused statistically significant increase in the level of DNA damage, thus indicating that amitraz possesses genotoxic potential. The concentration of amitraz that produced the highest DNA damage (3.5 g/mL) was chosen for further analysis with the antioxidant catalase. The obtained results showed that co-treatment with antioxidant catalase (100 IU/mL or 500 IU/mL) significantly reduced the level of DNA damage, indicating the possible involvement of reactive oxygen species in DNA damaging effects of amitraz. Flow cytometric analysis revealed increase of the apoptotic index following treatment with amitraz. However, co-treatment with catalase reduced the apoptotic index, while treatment with catalase alone reduced the percentage of apoptotoc cells even in comparison with the negative control. Therefore, catalase had protective effects against ROS-mediated DNA damage and apoptosis.

  15. From lifetime to evolution: timescales of human gut microbiota adaptation

    OpenAIRE

    Sara eQuercia; Marco eCandela; Cristina eGiuliani; Silvia eTurroni; Donata eLuiselli; Simone eRampelli; Patrizia eBrigidi; Claudio eFranceschi; Maria Giulia eBacalini; Paolo eGaragnani; Chiara ePirazzini

    2014-01-01

    Human beings harbor gut microbial communities that are essential to preserve human health. Molded by the human genome, the gut microbiota is an adaptive component of the human superorganisms that allows host adaptation at different timescales, optimizing host physiology from daily life to lifespan scales and human evolutionary history. The gut microbiota continuously changes from birth up to the most extreme limits of human life, reconfiguring its metagenomic layout in response to daily varia...

  16. From lifetime to evolution: timescales of human gut microbiota adaptation

    OpenAIRE

    Quercia, Sara; Candela, Marco; Giuliani, Cristina; Turroni, Silvia; Luiselli, Donata; Rampelli, Simone; Brigidi, Patrizia; Franceschi, Claudio; Bacalini, Maria Giulia; Garagnani, Paolo; Pirazzini, Chiara

    2014-01-01

    Human beings harbor gut microbial communities that are essential to preserve human health. Molded by the human genome, the gut microbiota (GM) is an adaptive component of the human superorganisms that allows host adaptation at different timescales, optimizing host physiology from daily life to lifespan scales and human evolutionary history. The GM continuously changes from birth up to the most extreme limits of human life, reconfiguring its metagenomic layout in response to daily variations i...

  17. Membrane characteristics and functional analysis of human T and B lymphocytes : a contributions to the analysis of immunodeficiency in children

    NARCIS (Netherlands)

    R.K.B. Schuurman

    1980-01-01

    textabstractConcepts of the immune system in man change along with models based on experimental research (52). In the past three decennia the function of human lymphocytes~ their differentiation pathways and their disorders have been unraveled by a close collaboration between animal and human immuno

  18. The role of geography in human adaptation.

    Directory of Open Access Journals (Sweden)

    Graham Coop

    2009-06-01

    Full Text Available Various observations argue for a role of adaptation in recent human evolution, including results from genome-wide studies and analyses of selection signals at candidate genes. Here, we use genome-wide SNP data from the HapMap and CEPH-Human Genome Diversity Panel samples to study the geographic distributions of putatively selected alleles at a range of geographic scales. We find that the average allele frequency divergence is highly predictive of the most extreme F(ST values across the whole genome. On a broad scale, the geographic distribution of putatively selected alleles almost invariably conforms to population clusters identified using randomly chosen genetic markers. Given this structure, there are surprisingly few fixed or nearly fixed differences between human populations. Among the nearly fixed differences that do exist, nearly all are due to fixation events that occurred outside of Africa, and most appear in East Asia. These patterns suggest that selection is often weak enough that neutral processes -- especially population history, migration, and drift -- exert powerful influences over the fate and geographic distribution of selected alleles.

  19. Comparison of micronucleus frequency in human lymphocytes irradiated in vitro and in vivo

    International Nuclear Information System (INIS)

    A Lymphomas case was treated with whole body irradiation. The results showed that micronucleated cell frequency and micronucleus frequency were very similar between the blood samples irradiated in vitro and in vivo. The differences were not significant (p>0.5). The patterns of the curves obtained from regression analysis were identical, and the differences among the two regression equations of the same parameter were not significant, it is considered that dose effect was almost the same between the blood samples irradiated in vitro and in vivo in certain dose extent. The micronucleus frequency of human peripheral blood lymphocytes could be applied as a supplementary criterion for dose estimation to irradiated human at early stage of nuclear accident

  20. Radioprotective Properties of Allium sativum (Garlic Extract on Cultured Human Lymphocytes against Electron Beam Radiation

    Directory of Open Access Journals (Sweden)

    Shama N Rao

    2015-03-01

    Full Text Available The radioprotective effects of naturally occurring compounds from herbs have been investigated in vitro and in vivo considering their ethnopharmacological role in prevention and treatment of cancer. Allium sativum supplementation in diet has been shown to be beneficial to cancer patients. The present study was designed to detect the radioprotective effect of garlic extract (GE on cultured human peripheral blood lymphocytes. Garlic bulbs were extracted using ethanol and water separately followed by assays on antioxidant activities to assess the efficiency of radical scavenging capacity of various extracts. Lymphocytes were treated with different concentrations of GE for 2, 4, 6 and 24 hr periods. Cell survival was determined by tryphan blue dye exclusion assay, single strand DNA damage by alkaline comet assay and in vitro cytogenetic damages were evaluated by micronucleus assays. Ethanol boiled GE showed highest radical scavenging capacity and reducing property. Treatment of GE to lymphocytes before and after exposure to 4Gy of electron beam radiation (EBR the percentage of tail DNA was reduced from 24.06±3.92 to 2.87±0.18. The elevated micronucleus formation in radiation control group (13.15±0.75 was significantly reduced in various concentrations of GE treated groups (10.35±0.44, 7.05±1.17, 6.42±0.47 respectively. Cells treated with GE at 10µg/mL showed maximum viability after exposure to EBR. Present investigations indicate that ethanol boiled GE shows good radiation protection at 10µg/mL concentration. However, increase in concentration above this dose though resulted in higher protection, increased cell toxicity was also noticed.

  1. p53 mutations in human lymphoid malignancies: Association with Burkitt lymphoma and chronic lymphocytic leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Gaidano, G.; Ballerini, P.; Gong, J.Z.; Inghirami, G.; Knowles, D.M.; Dalla-Favera, R. (Columbia Univ., New York, NY (United States)); Neri, A, (Columbia Univ., New York, NY (United States) Centro Malattie del Sangue G. Marcora, Milan (Italy)); Newcomb, E.W. (New York Univ. School of Medicine, New York (United States)); Magrath, I.T. (National Cancer Institute, Bethesda, MD (United States))

    1991-06-15

    The authors have investigated the frequency of p53 mutations in B- and T-cell human lymphoid malignancies, including acute lymphoblastic leukemia, the major subtypes of non-Hodgkin lymphoma, and chronic lymphocytic leukemia. p53 exons 5-9 were studied by using genomic DNA from 197 primary tumors and 27 cell lines by single-strand conformation polymorphism analysis and by direst sequencing of PCR-amplified fragments. Mutations were found associated with (i) Burkitt lymphoma (9/27 biopsoes; 17/27 cell lines) and its leukemic counterpart L{sub 3}-type B-cell acute lymphoblastic leukemia (5/9), both of which also carry activated c-myc oncogenes, and (ii) B-cell chronic lymphocytic leukemia (6/40) and, in particular, its stage of progression known as Richter's transformation (3/7). Mutations were not found at any significant frequency in other types of non-Hodgkin lymphoma or acute lymphoblastic leukemia. In many cases, only the mutated allele was detectable, implying loss of the normal allele. These results suggest that (1) significant differences in the frequency of p53 mutations are present among subtypes of neoplasms derived from the same tissue; (2) p53 may play a role in tumor progression in B-cell chronic lymphocytic leukemia; (3) the presence of both p53 loss/inactivation and c-myc oncogene activation may be important in the pathogenesis of Burkitt lymphoma and its leukemia form L{sub 3}-type B-cell acute lymphoblastic leukemia.

  2. Rapid alterations of cell cycle control proteins in human T lymphocytes in microgravity

    Directory of Open Access Journals (Sweden)

    Thiel Cora S

    2012-01-01

    Full Text Available Abstract In our study we aimed to identify rapidly reacting gravity-responsive mechanisms in mammalian cells in order to understand if and how altered gravity is translated into a cellular response. In a combination of experiments using "functional weightlessness" provided by 2D-clinostats and real microgravity provided by several parabolic flight campaigns and compared to in-flight-1g-controls, we identified rapid gravity-responsive reactions inside the cell cycle regulatory machinery of human T lymphocytes. In response to 2D clinorotation, we detected an enhanced expression of p21 Waf1/Cip1 protein within minutes, less cdc25C protein expression and enhanced Ser147-phosphorylation of cyclinB1 after CD3/CD28 stimulation. Additionally, during 2D clinorotation, Tyr-15-phosphorylation occurred later and was shorter than in the 1 g controls. In CD3/CD28-stimulated primary human T cells, mRNA expression of the cell cycle arrest protein p21 increased 4.1-fold after 20s real microgravity in primary CD4+ T cells and 2.9-fold in Jurkat T cells, compared to 1 g in-flight controls after CD3/CD28 stimulation. The histone acetyltransferase (HAT inhibitor curcumin was able to abrogate microgravity-induced p21 mRNA expression, whereas expression was enhanced by a histone deacetylase (HDAC inhibitor. Therefore, we suppose that cell cycle progression in human T lymphocytes requires Earth gravity and that the disturbed expression of cell cycle regulatory proteins could contribute to the breakdown of the human immune system in space.

  3. HLA-G inhibits xenogenetic cytotoxicity mediated by human NK cells and T lymphocytes against PECs

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In order to investigate whether the non-classi-cal HLA-G classⅠmolecule protects the porcine endothelial cells (PECs) from the lysis mediated by human immune cells in pig to human discordant xenotransplantation, we have cloned HLA-G cDNA from a human placenta by RT-PCR. Mammalian expression vector, pEFG-neo, was constructed by insertion of HLA-G cDNA in pEF-neo. We obtained efficiently expressed PECs by stable transfection. Cytotoxicity assay showed that overexpression of HLA-G on PECs was sufficient to inhibit human NK-92 cell lysis. The level of lysis was equal to or less than that of the lysis of human umbilical vein endothelial cells mediated by human NK-92 cells. It also indicated that HLA-G inhibited the lysis of PECs mediated by xeno-antigen specific T lymphocytes. The reduction of lysis ranged between 59.1% and 88.9%. These findings suggest that the transgenic approach to overexpress HLA-G is believed to be a new immunotherapy in overcoming the immune rejections in xenotransplantion, including delayed xenograft rejection and cell-mediated rejection.

  4. Radioprotective effect of sesamol on γ-radiation induced DNA damage, lipid peroxidation and antioxidants levels in cultured human lymphocytes

    International Nuclear Information System (INIS)

    Sesamol pretreated (1, 5 and 10 μg/ml) lymphocytes were exposed to different doses of γ-radiation, i.e., 1, 2 and 4 Gray (Gy) and the cellular changes were estimated by using cytokinesis blocked micronucleus assay (MN), dicentric aberration (DC), thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH) and the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). Radiation significantly increased MN, DC frequencies, TBARS levels and decreased GSH and antioxidant enzyme levels in a dose dependent manner. The highest damage to lymphocytes was observed at 4 Gy irradiation. On the other hand, sesamol pretreatment significantly decreased MN, DC frequencies, TBARS levels and increased GSH levels and SOD, CAT and GPx activities in a concentration dependent manner. At 1 Gy irradiation all concentrations of sesamol (1, 5 and 10 μg/ml) significantly protects the lymphocytes from radiation damage. At 2 Gy irradiation 5 and 10 μg/ml of sesamol shows significant radioprotection. Since the highest damage was observed at 4 Gy irradiation both 1 and 5 μg/ml of sesamol pretreatment were not sufficient to protect the lymphocytes from radiation damage but 10 μg/ml of sesamol significantly (p < 0.05) protects the lymphocytes from radiation effect. Thus, sesamol pretreatment gives significant protection to cultured human lymphocytes against γ-radiation induced cellular damage. The possible mechanism involved in the radioprotective influence of sesamol is discussed

  5. Internalization of /sup 125/I-insulin by IM-9 cultured human lymphocytes: a comparison between A14-monoiodo-pork and biosynthetic human insulin

    Energy Technology Data Exchange (ETDEWEB)

    Carpentier, J.L.; Halban, P.A.; Renold, A.E.; Orci, L.

    Human insulin synthesized from A- and B-chains separately produced in Escherichia coli from cloned genes was characterized by examining its interaction biochemically and morphologically with IM-9 cultured human lymphocytes. Biosynthetic human insulin (BHI) behaves similarly to pork insulin with respect both to its binding properties and to the rate and magnitude at which it is internalized by the cells.

  6. Internalization of 125I-insulin by IM-9 cultured human lymphocytes: a comparison between A14-monoiodo-pork and biosynthetic human insulin

    International Nuclear Information System (INIS)

    Human insulin synthesized from A- and B-chains separately produced in Escherichia coli from cloned genes was characterized by examining its interaction biochemically and morphologically with IM-9 cultured human lymphocytes. Biosynthetic human insulin (BHI) behaves similarly to pork insulin with respect both to its binding properties and to the rate and magnitude at which it is internalized by the cells

  7. In-vitro carbofuran induced micronucleus formation in human blood lymphocytes.

    Science.gov (United States)

    Sharma, R K; Rai, D K; Sharma, B

    2012-12-22

    The farmers in general get exposed to different chemicals including pesticides. Many of these compounds are capable of inducing mutations in DNA and lead to several diseases including cancer. Carbofuran is a broad spectrum pesticide and frequently used in agricultural practices in India. In this study we intended to evaluate DNA damage inflicted by pesticide exposure in human blood lymphocytes under in vitro condition. The lymphocytes were exposed to varying concentrations of carbofuran (0—50μM) and analyzed by means of the micronucleus (MN) test. The results obtained showed significant increase in MN frequency after exposure to 5, 10, 25 and 50μM of carbofuran as compared to the control group. The frequencies of MN were observed to be in concentration dependent manner. As we further increase the concentration of carbofuran, we observed significant decrease in the mean percentage of binucleated cells (70—49%) and increase in the number of micronuclei formed per 1000 binucleated cells. Simultaneously, we also observed reduction in Cytokinesis—Block Proliferation index (CBPI) with increase in the carbofuran concentrations. The results indicate that this pesticide may exhibit genotoxic effect at higher concentrations. This study emphasizes the need to reinforce the good practices campaigns in order to enlighten those who work with pesticides and also to make them aware about the importance of using protective measures.

  8. Human yeast-specific CD8 T lymphocytes show a nonclassical effector molecule profile.

    Science.gov (United States)

    Breinig, Tanja; Scheller, Nicoletta; Glombitza, Birgit; Breinig, Frank; Meyerhans, Andreas

    2012-05-01

    Pathogenic yeast and fungi represent a major group of human pathogens. The consequences of infections are diverse and range from local, clinically uncomplicated mycosis of the skin to systemic, life-threatening sepsis. Despite extensive MHC class I-restricted frequencies of yeast-specific CD8 T lymphocytes in healthy individuals and the essential role of the cell-mediated immunity in controlling infections, the characteristics and defense mechanisms of antifungal effector cells are still unclear. Here, we describe the direct analysis of yeast-specific CD8 T lymphocytes in whole blood from healthy individuals. They show a unique, nonclassical phenotype expressing granulysin and granzyme K in lytic granules instead of the major effector molecules perforin and granzyme B. After stimulation in whole blood, yeast-specific CD8 T cells degranulated and, upon cultivation in the presence of IL-2, their granula were refilled with granulysin rather than with perforin and granzyme B. Moreover, yeast-specific stimulation through dendritic cells but not by yeast cells alone led to degranulation of the effector cells. As granulysin is the only effector molecule in lytic granules known to have antifungal properties, our data suggest yeast-specific CD8 T cells to be a nonclassical effector population whose antimicrobial effector machinery seems to be tailor-made for the efficient elimination of fungi as pathogens.

  9. Induction of sister chromatid exchanges by coal dust and tobacco snuff extracts in human peripheral lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Tucker, J.D.; Ong, T.

    1985-01-01

    The organic solvent extracts of sub-bituminous coal dust and tobacco snuff, both together and separately, were tested for the induction of sister chromatid exchanges (SCEs) in human peripheral lymphocytes. The results indicate that these extracts induced SCEs, and that when tested together synergistically induced SCEs in two of three donors. Studies with the organic solvent extracts of all five ranks of coal indicate that the extracts of bituminous, lignite, and peat, but not anthracite, induced SCEs. Similar experiments conducted with water extracts, induced SCEs, and that anthracite was equivocal. To determine whether individuals differed in their SCE responses to coal dust extracts, lymphocytes from five donors were tested with organic solvent extracts of bituminous and sub-bituminous coal. An analysis of variance indicates that the SCE response was significantly influenced by the donor and each of the two coal extracts. The findings presented here suggest that coal dust, with or without tobacco snuff, may play a role in the elevated incidence of gastric cancer in coal miners. Because water extracts of some ranks of coal induced SCEs, there exists the possibility of adverse environmental effects due to coal leachates.

  10. Effects of ascorbic acid and sodium ascorbate on cyclic nucleotide metabolism in human lymphocytes.

    Science.gov (United States)

    Atkinson, J P; Weiss, A; Ito, M; Kelly, J; Parker, C W

    1979-01-01

    L-ascorbic acid (LAA) augmented cGMP many-fold in highly purified human peripheral blood lymphocytes. The cGMP response occurred within 10 sec and persisted for at least 60 min. D-ascorbic acid (DAA) and dehydroascorbic acid (DHAA) were also equally active in enhancing cGMP concentrations but metabolic precursors of ascorbic acid and other inorganic acids did not increase cGMP levels. Determination of the amount of DHAA contaminating the LAA precluded the possibility that it was solely responsible for the enhanced cGMP levels. The sodium or calcium salts of ascorbic acid did not increase cGMP concentrations. If these neutralized preparations were acidified, increased cGMP concentrations were then noted. In broken cell preparations, LAA, DAA, and DHAA and to a lesser extent sodium ascorbate (NaA) enhanced guanylate cyclase activity while neither inhibited cAMP or cGMP phosphodiesterase (PDE) activity. The possible role of H2O2, fatty acid liberation, prostaglandin production, oxidizing-reducing agents, and free radical formation in mediating the effects of ascorbic acid on cGMP levels were evaluated, but none of these potential mechanisms were definitively proven to be a required intermediary for the cGMP enhancing activity of ascorbic acid. LAA, DHAA or NaA did not induce lymphocyte transformation or modulate lectin-induced mitogenesis. PMID:36416

  11. Chromosome aberration yields in human lymphocytes induced by fractionated doses of x-radiation

    International Nuclear Information System (INIS)

    Unstimulated (G0) human peripheral blood lymphocytes were exposed at 37degC to doses of 200 or 500 rad of X-rays delivered in two equal fractions. The dose fractions were separated by intervals of up to 7 h in the 200 rad study and up to 48 h for 500 rad. In both studies the mean levels of dicentrics and total unstable aberrations began to decline when fractions were delivered with intervals of greater than 2 h. With 200 rad the yield had decreased to an additive baseline (i.e. equal to only twice the yield of a single 100-rad fraction) by an interval of 4 h. Following 500 rad the yield declined until 8 h and then remained 20% above the expected additive baseline even when 48 h separated the fractions. Possible explanations for this discrepancy are discussed. In a second experiment PHA stimulated lymphocyte cultures were exposed to 2 doses of 125 rad of X-rays up to 7 h apart in an attempt to demonstrate the late peak in aberration yield originally reported by Lane. Control cultures received unsplit doses of 250 rad at the time of the corresponding second 125-rad fraction. No evidence of a late peak in dicentric yield was observed. The yield remained approximately the same irrespective of the time interval between fractions but these split dose yields were significantly different from the accompanying unsplit controls

  12. Differential Micronuclei Induction in Human Lymphocyte Cultures by Imidacloprid in the Presence of Potassium Nitrate

    Directory of Open Access Journals (Sweden)

    Polychronis Stivaktakis

    2010-01-01

    Full Text Available Humans are exposed to pesticides as a consequence of their application in farming or their persistence in a variety of media, including food, water, air, soil, plants, animals, and smoke. The interaction of pesticides with environmental factors may result in the alteration of their physicochemical properties. Square wave cathodic stripping voltammetry (SW-CSV, a technique that simulates electrodynamically the cellular membrane, is used to investigate whether the presence of potassium nitrate (KNO3 in the culture medium interferes with the genotoxic behavior of imidacloprid. The cytokinesis block micronuclei (CBMN method is used to evaluate imidacloprid's genotoxicity in the absence or presence of KNO3 in the culture medium and, as a consequence, its adsorption by lymphocytes. Comparing micronuclei (MN frequencies in control and imidacloprid-treated blood cell cultures, statistically significant differences were not detected. KNO3 did not induce MN frequencies compared to control. Statistically significant differences in MN frequencies were observed when blood cell cultures were treated with imidacloprid in the presence of increasing concentrations of KNO3. SW-CSV revealed that by increasing KNO3 molarity, imidacloprid's concentration in the culture medium decreased in parallel. This finding indicates that imidacloprid is adsorbed by cellular membranes. The present study suggests a novel role of a harmless environmental factor, such as KNO3, on the genotoxic behavior of a pesticide, such as imidacloprid. KNO3 rendered imidacloprid permeable to lymphocytes, resulting in elevated MN frequencies.

  13. Biological dosimetry: the potential use of radiation-induced apoptosis in human T-lymphocytes

    International Nuclear Information System (INIS)

    An assay for biological dosimetry based on the induction of apoptosis in human T-lymphocytes is described. Radiation-induced apoptosis was assessed by flow cytometric identification of cells displaying apoptosis-associated DNA condensation. CD4 and CD8 T-lymphocytes were analysed. They were recognized on the basis of their cell-surface antigens. Four parameters were measured for both cell types: cell size, granularity, antigen immunofluorescence and DNA content. Apoptosis was quantified as the fraction of CD4-, or CD8-positive cells with a characteristic reduction of cell size and DNA content. At doses below 1 Gy, levels of radiation-induced apoptosis increased for up to 5 days after irradiation. Optimal dose discrimination was observed 4 days after irradiation, at which time the dose-response curves were linear, with a slope of 8% ± 0.5% per 0.1 Gy. In controlled, dose-response experiments the lowest dose level at which the radiation-induced apoptosis frequency was still significantly above control was 0.05 Gy. After 5 days post-irradiation incubation, intra- and interdonor variations were measured and found to be similar; thus, apoptotic levels depend more on the dose than on the donor. The results demonstrate the potential of this assay as a biological dosimeter. (orig.)

  14. Clastogenic effect of atranorin, evernic acid, and usnic acid on human lymphocytes.

    Science.gov (United States)

    Stojanović, Gordana S; Stanković, Miroslava; Stojanović, Igor Z; Palić, Ivan; Milovanović, Vesna; Rancić, Sofija

    2014-04-01

    Three lichen secondary metabolites atranorin (1), evernic acid (2), and usnic acid (3), were evaluated for their in vitro clastogenic and antiproliferative effects on human lymphocytes using the cytochalasin-B blocked micronucleus (CBMN) assay at concentrations of 2 microg/mL, 4 microg/mL and 6 microg/mL of final culture solution. The frequency of micronucleus (MN) was scored in binucleated cells, and cytokinesis-block proliferation index (CBPI) was calculated. Among the tested compounds, 3 exhibited the most prominent effect decreasing the frequency of MN in the range of 42.5% - 48.9%, that is about double of the positive control amifostin WR-2721 that reduces MN frequency for 22.0%. The effect of evernic acid was approximately equal to action of amifostin (23.2% -32.9%). Atranorin at concentrations of 2 microg/mL and 4 microg/mL decreasing the frequency of MN only for 11.1% and 1.8%, while in concentration of 6 microg/mL increases the frequency of MN for 9.6 %. The comparable CBPI values of the investigated compounds and control suggested that they did not show a statistically significant inhibitory effect on lymphocyte cell proliferation at applied concentrations. PMID:24868868

  15. Effects of colcemid concentration on chromosome aberration analysis in human lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Kanda, Reiko; Hayata, Isamu; Kobayashi, Sadayoshi (National Inst. of Radiological Sciences, Chiba (Japan)); Jiang, Tao

    1994-03-01

    As a part of technical improvements of chromosome aberration analysis on human peripheral lymphocytes for biological radiation dosimetry, we examined the optimal conditions for the use of colcemid in chromosome preparation in order to obtain enough number of cells at metaphase in the first cell division. When treated with colcemid at concentrations below 0.01 [mu]g/ml from the beginning of culture, cultures harvested at 48 hours had low mitotic indices. Colcemid treatment at 0.025 to 0.05 [mu]g/ml during 48 hours resulted in high mitotic indices (8 to 15%) and almost of the mitotic cells remaining in the 1st cell division, suggesting that this range of colcemid concentration was appropriate for continuous treatment with colcemid. We further examined the effect of colcemid concentration on the quantitative consistency of the yields of radiation-induced chromosome aberration. Repeated experiments showed that the yield of dicentrics and centric rings in the culture having colcemid at 0.025 [mu]g/ml concentration were larger than that at 0.05 [mu]g/ml. These data indicate the importance of assuring the accuracy of colcemid concentration in the lymphocyte culture for cytogenetic radiation dosimetry. (author).

  16. Karyotypes of Human Lymphocytes Exposed to High-Energy Iron Ions

    Science.gov (United States)

    Durante, M.; George, K.; Wu, H.; Cucinotta, F. A.

    2002-01-01

    Chromosomal aberrations were analyzed using multicolor fluorescence in situ hybridization (mFISH) in human peripheral blood lymphocytes after in vitro exposure to gamma rays or accelerated (56)Fe ions (1 GeV/nucleon, 145 keV/microm) at Brookhaven National Laboratory (Upton, NY). Doses of 0.3 and 3 Gy were used for both radiation types. Chromosomes were prematurely condensed by a phosphatase inhibitor (calyculin A) to avoid the population selection bias observed at metaphase as a result of the severe cell cycle delays induced by heavy ions. A total of 1053 karyotypes (G(2) and M phases) were analyzed in irradiated lymphocytes. Results revealed different distribution patterns for chromosomal aberrations after low- and high-LET radiation exposures: Heavy ions induced a much higher fraction of cells with multiple aberrations, while the majority of the aberrant cells induced by low doses of gamma rays contained a single aberration. The high fraction of complex-type exchanges after heavy ions leads to an overestimation of simple-type asymmetrical interchanges (dicentrics) from analysis of Giemsa-stained samples. However, even after a dose of 3 Gy iron ions, about 30% of the cells presented no complex-type exchanges. The involvement of individual chromosomes in exchanges was similar for densely and sparsely ionizing radiation, and no statistically significant evidence of a nonrandom involvement of specific chromosomes was detected.

  17. Effect of propolis on mitotic and cellular proliferation indices in human blood lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Montoro, A.; Almonacid, M.; Villaescusa, J. [Valencia Hospital Univ. la Fe, Servicio de Proteccion Radiologica (Spain); Barquinero, J. [Barcelona Univ. Autonom, Servicio de Dosimetria Biologica, Unidad de Antropologia, Dept. de Biologia Animal, Vegetal y Ecologia, barcelona (Spain); Barrios, L. [Barcelona Univ. Autonoma, Dept. de Biologia Celular y Fisiologia. Unidad de Biologia Celular (Spain); Verdu, G. [Valencia Univ. Politecnica, Dept. de Ingenieria Quimica y Nuclear (Spain); Perez, J. [Hospital la Fe, Seccion de Radiofisica, Servicio de Radioterapia, valencia (Spain)

    2006-07-01

    The study of the frequency of chromosomal aberrations per cell is the tool used in Biological dosimetry studies. Using dose-effect calibration curve obtained in our laboratory, we can evaluate the radioprotector effect of the EEP (ethanolic extract of propolis) in cultures in vitro. Propolis is the generic name for resinous substance collected by honeybees. The results showed a reduction in chromosomal aberrations's frequency of up to 50 %. The following study consisted of analyzing human peripheral blood lymphocytes exposed to 2 Gy {gamma} rays, in presence and absence of EEP, the change in the frequency of chromosome aberrations was analysed with biological dosimetry. The protection against the formation of dicentric and ring was dose-dependent, but there seemed to be a maximum protection, i.e. a further increase in the concentration of EEP does not show additional protection. This work studies the effect of the EEP of the cellular cycle using the mitotic and cellular proliferation index, as an alternative for the screening cytostatic activity. The results indicate that the lymphocytes which were cultures in presence of EEP exhibited a significant and dependent-concentration decrease in mitotic index and proliferation kinetics. The possible mechanisms involved in the radioprotective influence of EEP are discussed. (authors)

  18. DNA repair capacity of cultured human lymphocytes exposed to mutagens measured by the comet assay and array expression analysis.

    Science.gov (United States)

    Bausinger, Julia; Speit, Günter

    2015-11-01

    Repair of mutagen-induced DNA lesions during transportation, storage and cultivation of lymphocytes may have a significant impact on results obtained in human biomonitoring after occupational and environmental exposure of human populations to genotoxic chemicals. Using the comet assay in combination with the repair inhibitor aphidicolin and array gene expression analysis of 92 DNA repair genes, we investigated the repair of DNA lesions induced by methyl methanesulfonate (MMS) and benzo[a]pyrenediolepoxide (BPDE) in phytohaemagglutinin (PHA)-stimulated cultured human lymphocytes in the time segment before replication. The comet assay indicated fast repair of MMS-induced damage during the first hours of cultivation. In contrast, removal of BPDE-induced lesions was slower and significant amounts of damage seem to persist until S-phase. Gene expression analysis revealed that PHA stimulation had a clear effect on gene regulation in lymphocytes already during the first 18h of cultivation. Under the conditions of this study, genotoxic concentrations of MMS did not induce significant changes in gene expression. In contrast, exposure to BPDE led to altered expression of several genes in a time- and concentration-related manner. Of the significantly up-regulated genes, only two genes (XPA and XPC) were directly related to nucleotide excision repair. Our results suggest that PHA stimulation of human lymphocytes influences the expression of DNA repair genes in human lymphocytes. The effect of induced DNA damage on gene expression is comparatively low and depends on the mutagens used. PHA-stimulated lymphocytes repair induced DNA damage before they start to replicate but the repair activity during the first 18h of cultivation is not affected by changes in the expression of DNA repair genes during this period of time.

  19. Effect of insulin and glucose on adenosine metabolizing enzymes in human B lymphocytes.

    Science.gov (United States)

    Kocbuch, Katarzyna; Sakowicz-Burkiewicz, Monika; Grden, Marzena; Szutowicz, Andrzej; Pawelczyk, Tadeusz

    2009-01-01

    In diabetes several aspects of immunity are altered, including the immunomodulatory action of adenosine. Our study was undertaken to investigate the effect of different glucose and insulin concentrations on activities of adenosine metabolizing enzymes in human B lymphocytes line SKW 6.4. The activity of adenosine deaminase in the cytosolic fraction was very low and was not affected by different glucose concentration, but in the membrane fraction of cells cultured with 25 mM glucose it was decreased by about 35% comparing to the activity in cells maintained in 5 mM glucose, irrespective of insulin concentration. The activities of 5'-nucleotidase (5'-NT) and ecto-5'-NT in SKW 6.4 cells depended on insulin concentration, but not on glucose. Cells cultured with 10(-8) M insulin displayed an about 60% lower activity of cytosolic 5'-NT comparing to cells maintained at 10(-11) M insulin. The activity of ecto-5'-NT was decreased by about 70% in cells cultured with 10(-8) M insulin comparing to cells grown in 10(-11) M insulin. Neither insulin nor glucose had an effect on adenosine kinase (AK) activity in SKW 6.4 cells or in human B cells isolated from peripheral blood. The extracellular level of adenosine and inosine during accelerated catabolism of cellular ATP depended on glucose, but not on insulin concentration. Concluding, our study demonstrates that glucose and insulin differentially affect the activities of adenosine metabolizing enzymes in human B lymphocytes, but changes in those activities do not correlate with the adenosine level in cell media during accelerated ATP catabolism, implying that nucleoside transport is the primary factor determining the extracellular level of adenosine.

  20. Ontogeny of innate T lymphocytes - some innate lymphocytes are more innate then others

    Directory of Open Access Journals (Sweden)

    David eVermijlen

    2014-10-01

    Full Text Available Innate lymphocytes have recently received a lot of attention. However, there are different ideas about the definition of what is innate in lymphocytes. Lymphocytes without V(DJ-rearranged antigen receptors are now termed innate lymphoid cells (ILCs and include cells formerly known as NK cells. Also, lymphocytes that are innate should be able to recognize microbial or stress-induced patterns and react rapidly without prior sensitization, as opposed to adaptive immune responses. Formally, genuine innate lymphocytes would be present before or at birth. Here we review the ontogeny of human and mouse innate T lymphocyte populations. We focus on γδ T cells, which are prototype lymphocytes that often use their V(DJ rearrangement machinery to generate genetically encoded predetermined recombinations of antigen receptors. We make parallels between the development of γδ T cells with that of innate aβ T cells (invariant (iNKT and mucosa-associated invariant T (MAIT cells and compare this with the ontogeny of innate B cells and innate lymphoid cells (ILCs, including NK cells. We conclude that some subsets are more innate than others, i.e. innate lymphocytes that are made primarily early in utero during gestation while others are made after birth. In practice, a ranking of innateness by ontogeny has implications for the reconstitution of innate lymphocyte subsets after hematopoietic stem cell transplantation (HSCT.

  1. Low-level pre-irradiation of human lymphocytes is not an absolutely beneficial phenomenon: on the problems of induced severe synergism

    International Nuclear Information System (INIS)

    Since the discovery of radioadaptive response in cultured human lymphocytes, one of the most important questions has been that of whether this low-level pre-irradiation is absolutely beneficial or not. Furthermore, there is a controversy on the possible implications of the adaptive response in the estimation of risks of low-level radiation exposures. Several recent reports indicate that radioadaptive response can induce beneficial phenomena which protect the cells against naturally occurring as well as radiation induced alterations that lead to cell transformation, and processes that increase the latency for development of AML, or even increase the survival rate of animals after a high-level irradiation. Surprisingly, it has even been indicated that chronic low doses can increase the life span of animals. On the other hand, there are reports indicating that the induction of radioadaptive response in some cases, such as radiotherapy, can be a problematic phenomenon. Despite the fact that there is growing evidence for the existence of radioadaptive response, some other investigators and we have reported entirely negative results as well as synergistic effect in many healthy individuals. In this regard, we found a young healthy donor who did not show adaptive response in any experiment. On the contrary, he showed a severe extraordinary hypersensitivity to subsequent irradiation (up to 200%) after a common adapting dose. Interestingly, this non-responder donor showed no adaptive response in all of our 12 subsequent experiments performed in 3 series. Despite the fact that we do not know the approximate frequency of individuals who show such an extraordinary synergistic effect in the population, it may be concluded that considering the low-level pre-irradiation of human lymphocytes as an absolutely beneficial phenomenon can be a great error. (author)

  2. Inhibiting the expression of CD28 costimulatory molecule on human lymphocytes by special siRNA

    Institute of Scientific and Technical Information of China (English)

    XU Kai-lin; ZHANG Ying; PAN Xiu-ying; LU Qun-xian

    2005-01-01

    Background The B7/CD28 pathway provides critical costimulatory signals for complete T cell activation, and members of this pathway have served as useful targets for immunotherapeutic strategies. In this study, we investigated the RNA interference (RNAi) effect induced by small interfering RNA (siRNA) targeting CD28 mRNA on human lymphocytes and its specificity.Methods According to CD28 gene sequence, we designed and synthysized three different siRNAs (siRNA-1, siRNA-2, siRNA-3) containing 21 bases using SilencerTM siRNA construction kit. These siRNAs were transfected into freshly isolated human lymphocytes with Lipofectamine 2000 reagent. At 24-hour, 48-hour and 72-hour post transfection, these cells were collected and analyzed. The changes of surface expression of CD28 gene were detected by flow cytometry, and the changes of CD28 mRNA levels were determined by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). The cell viability of transfected lymphocytes was determined by methyl thiazolyl tetrazolium (MTT) assay and trypan blue dye exclusion assay. Results Three siRNAs (siRNA-1, siRNA-2, siRNA-3) specifically targeting CD28 mRNA were successfully designed and constructed. Flow cytometry analysis showed that a decrease in CD28 expression was detectable at 24-hour post transfection. Different siRNA showed different inhibition effects on CD28 expression. At 48-hour post transfection, the degrees of reduction with siRNA-1, siRNA-2 and siRNA-3 were 22.10%±1.63%, 73.50%±1.02% and 42.90%±0.89% respectively compared with the control (P0.05). Moreover, lymphocytes treated with siRNA-co showed no marked reduction in CD28 expression (5.07%±0.96%) (P>0.05). The results of semi-quantitative RT-PCR assay indicated CD28 mRNA level was inhibited after transfection of specific siRNAs. At least 4-fold of reduction in siRNA-2 group occurred at 48-hour post transfection compared with the control (P0.05). Conclusions Three different siRNAs were

  3. The impact of lymphocyte isolation on induced DNA damage in human blood samples measured by the comet assay.

    Science.gov (United States)

    Bausinger, Julia; Speit, Günter

    2016-09-01

    The comet assay is frequently used in human biomonitoring for the detection of exposure to genotoxic agents. Peripheral blood samples are most frequently used and tested either as whole blood or after isolation of lymphocytes (i.e. peripheral blood mononuclear cells, PBMC). To investigate a potential impact of lymphocyte isolation on induced DNA damage in human blood samples, we exposed blood ex vivo to mutagens with different modes of genotoxic action. The comet assay was performed either directly with whole blood at the end of the exposure period or with lymphocytes isolated directly after exposure. In addition to the recommended standard protocol for lymphocyte isolation, a shortened protocol was established to optimise the isolation procedure. The results indicate that the effects of induced DNA strand breaks and alkali-labile sites induced by ionising radiation and alkylants, respectively, are significantly reduced in isolated lymphocytes. In contrast, oxidative DNA base damage (induced by potassium bromate) and stable bulky adducts (induced by benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide; BPDE) seem to be less affected. Our findings suggest that in vivo-induced DNA damage might also be reduced in isolated lymphocytes in comparison with the whole blood depending of the types of DNA damage induced. Because only small genotoxic effects can generally be expected in human biomonitoring studies with the comet assay after occupational and environmental exposure to genotoxic agents, any loss might be relevant and should be avoided. The possibility of such effects and their potential impact on variability of comet assay results in human biomonitoring should be considered when performing or evaluating such kind of studies. PMID:27154923

  4. HIV-1 Capsid Assembly Inhibitor (CAI) Peptide: Structural Preferences and Delivery into Human Embryonic Lung Cells and Lymphocytes

    OpenAIRE

    Braun, Klaus; Frank, Martin; Pipkorn, Rüdiger; Reed, Jennifer; Spring, Herbert; Debus, Jürgen; Didinger, Bernd; von der Lieth, Claus-Wilhelm; Wiessler, Manfred; Waldeck, Waldemar

    2008-01-01

    The Human immunodeficiency virus 1 derived capsid assembly inhibitor peptide (HIV-1 CAI-peptide) is a promising lead candidate for anti-HIV drug development. Its drawback, however, is that it cannot permeate cells directly. Here we report the transport of the pharmacologically active CAI-peptide into human lymphocytes and Human Embryonic Lung cells (HEL) using the BioShuttle platform. Generally, the transfer of pharmacologically active substances across membranes, demonstrated by confocal las...

  5. HIV-1 Capsid Assembly Inhibitor (CAI) Peptide: Structural Preferences and Delivery into Human Embryonic Lung Cells and Lymphocytes

    OpenAIRE

    Klaus Braun, Martin Frank, Rüdiger Pipkorn, Jennifer Reed, Herbert Spring, Jürgen Debus, Bernd Didinger, Claus-Wilhelm von der Lieth, Manfred Wiessler, Waldemar Waldeck

    2008-01-01

    The Human immunodeficiency 1 derived capsid assembly inhibitor peptide (HIV-1 CAI-peptide) is a promising lead candidate for anti-HIV drug development. Its drawback, however, is that it cannot permeate cells directly. Here we report the transport of the pharmacologically active CAI-peptide into human lymphocytes and Human Embryonic Lung cells (HEL) using the BioShuttle platform. Generally, the transfer of pharmacologically active substances across membranes, demonstrated by confocal laser sca...

  6. Measurement of in vivo HGPRT-deficient mutant cell frequency using a modified method for cloning human peripheral blood T-lymphocytes

    International Nuclear Information System (INIS)

    Approximately 80 % of human peripheral blood T-lymphocytes could be cloned in the presence of crude Interleukin-2, phytohemagglutinin, and X-irradiated autologous lymphocytes and Raji B-cells. This modified cloning method was used to measure the in vivo frequency of HGPRT-deficient mutant T-lymphocytes. Repeated experiments using blood from the same individuals revealed that the frequency of mutant cells was almost constant for each individual even though the cloning efficiency of lymphocytes varied somewhat from experiment to experiment. Approximately 80 % of both wild-type unselected and 6-thioguanine-resistant colonies had helper/inducer and about 20 % had suppressor/cytotoxic T-lymphocyte markers. No difference was observed in the distribution of lymphocyte subsets between wild and mutant lymphocyte colonies. (author)

  7. Isolation and evaluation of cytogenetic effect of Brahmi saponins on cultured human lymphocytes exposed in vitro.

    Science.gov (United States)

    Kalachaveedu, Mangathayaru; Papacchan, Sunu; Sanyal, Sudip; Koshy, Teena; Telapolu, Srivani

    2015-01-01

    Major saponins of Brahmi (Bacopa monniera, Fam: Scrophulariaceae) - bacosides A and B - were isolated from the total methanol extract and characterised based on melting point, TLC, IR, (1)H NMR and (13)C NMR. They were evaluated for their in vitro cytogenetic effects on human peripheral blood lymphocytes by chromosomal aberration (CA) assay and sister chromatid exchange (SCE) assay. The frequency of chromatid type aberrations and reciprocal interchanges between sister chromatids in the treated cells was scored in comparison to the untreated control. At 30 μg/mL dose, bacoside A showed a statistically significant increase in the frequency of both CA and SCE and bacoside B showed an increase only in SCE. Our report of the genotoxicity of the saponins is significant in view of the reports of anticancer activity of Brahmi extracts.

  8. The synergistic effect of ultrasound and ionising radiation on human lymphocytes

    International Nuclear Information System (INIS)

    Small lymphocytes in human peripheral blood were exposed to various sequences of ultrasound (2 W cm-2 for 30 min) 60Co γ-irradiation (45.32 rad min-1 for 200 rad total) to determine if a synergistic effect exists in producing chromosome damage. The results showed a statistically significant difference between controls and combined sequences where ultrasound was given either simultaneously with γ-rays or immediately after γ-rays. Both acentric fragments and dicentric chromosomes were significantly increased in the simultaneous sequences, but only fragments were significantly increased by ultrasound given immediately after γ-ray sequence. No significant difference were noted when ultrasound was used before γ-ray or when ultrasound was given later than 2 h after γ-ray. Several hypotheses that could explain this apparent synergism are discussed and a general description of further investigation is present. (author)

  9. Effects of 252Cf neutrons, transmitted through an iron block on human lymphocyte chromosome

    International Nuclear Information System (INIS)

    Chromosome aberration of human peripheral blood lymphocytes exposed to californium-252 (252Cf) neutrons transmitted through a 15 cm thick iron block was analysed. The spectrum of the filtered neutrons ranged from 0.1 to 2MeV with a peak at 0.7 MeV, simulating the Hiroshima atomic bomb neutron spectrum as shown in the Dosimetry System 1986 (DS86). Chromosome aberration frequencies after exposure to filtered and unfiltered 252Cf radiation were compared. Acentric ring chromosomes were significantly increased (p 0.1). The relative biological effectiveness (RBE) of the neutrons with respect to the formation of dicentrics and centric rings was 10.9 and 12.3 in the filtered and unfiltered conditions respectively, but the difference was not statistically significant. These results provide useful information for the re-evaluation of the biological effect of the Hiroshima atomic bomb radiations. (Author)

  10. Enhancement of chromosomal damage in human lymphocytes irradiated with X rays in the presence of iodine

    International Nuclear Information System (INIS)

    The production of chromosomal aberrations resulting from X irradiation of peripheral human blood lymphocytes in the presence or absence of Angioconray-80%, an iodised contrast medium, was investigated. This experiment confirmed an enhanced radiation effect, which is essentially explained by the increase of absorbed dose due to the high photoelectric cross section of iodine for X rays. Nevertheless the cytotoxicity of contrast medium alone cannot be neglected, and at a 0.1 M concentration in unirradiated blood it produced chromosome damage equivalent to 0.5 Gy. The distributions of aberrations among the cells, with and without contrast medium, were analysed using two statistical tests of goodness-of-fit for the Poissonian distribution. The results are discussed mostly in terms of dose enhancement factors. (author)

  11. Therapeutic activity of two xanthones in a xenograft murine model of human chronic lymphocytic leukemia

    Directory of Open Access Journals (Sweden)

    Berthou Christian

    2010-12-01

    Full Text Available Abstract Background We previously reported that allanxanthone C and macluraxanthone, two xanthones purified from Guttiferae trees, display in vitro antiproliferative and proapoptotic activities in leukemic cells from chronic lymphocytic leukemia (CLL and leukemia B cell lines. Results Here, we investigated the in vivo therapeutic effects of the two xanthones in a xenograft murine model of human CLL, developed by engrafting CD5-transfected chronic leukemia B cells into SCID mice. Treatment of the animals with five daily injections of either allanxanthone C or macluraxanthone resulted in a significant prolongation of their survival as compared to control animals injected with the solvent alone (p = 0.0006 and p = 0.0141, respectively. The same treatment of mice which were not xenografted induced no mortality. Conclusion These data show for the first time the in vivo antileukemic activities of two plant-derived xanthones, and confirm their potential interest for CLL therapy.

  12. Calcium transport by ionophorous peptides in dog and human lymphocytes detected by quin-2 fluorescence.

    Science.gov (United States)

    Deber, C M; Hsu, L C

    1986-01-29

    Synthetic peptides of structure cyclo(Glu(OBz)-Sar-Gly-(N-R)Gly)2 (I), electrogenic Ca2+-selective carriers in phospholipid vesicle membranes, are shown to mediate the uptake of Ca2+ ions into the cytoplasm of dog and human lymphocytes. Ca2+ transport by DECYL-2E (I, R = n-decyl) - monitored by measurements of the fluorescence of an intracellular dye, quin-2 - occurred at a rate comparable to that produced by electroneutral Ca2+ ionophores ionomycin and Br-A23187. Fluorescence quenching experiments using Mn2+ suggested a greater selectivity by DECYL-2E for Ca2+/Mn2+ vs. the other two ionophores. The result that Ca2+ ions can traverse biological membranes bound in a neutral cavity consisting exclusively of peptide carbonyl ligands may imply the functional significance of binding sites of similar structures in membrane transport proteins. PMID:3947349

  13. Failure to reproduce increased calcium uptake in human lymphocytes at purported cyclotron resonance exposure conditions

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, A.V.; Miller, M.W.; Azadniv, M.; Brayman, A.A. (Rochester Univ., NY (USA). Dept. of Biophysics); Carstensen, E.L. (Rochester Univ., NY (USA). Dept. of Electrical Engineering); Cox, C. (Rochester Univ., NY (USA). Dept. of Biostatistics)

    1991-10-01

    An attempt was made to verify a report (Liboff et al. 1987) that a unique combination of DC and AC magnetic field exposures at room temperature results in a 3-fold increase in {sup 45}Ca{sup 2+} uptake by human lymphocytes in vitro. Exposures at 'resonance condition', as well as at frequencies and amplitudes above and below the reported effective exposure conditions, were without effect, as were exposures at 37deg C. Treatment with ionomycin (0.25 {mu}M), a positive control, resulted in a highly significant increase {sup 45}Ca{sup 2+} uptake. Some experiments were performed simultaneously by different investigators. Their results did not differ significantly. All experiments were conducted 'double blindly'. (orig.).

  14. The changes of production of lymphokines from gamma irradiated human tonsillar lymphocytes: Pt. 2

    International Nuclear Information System (INIS)

    The human tonsillar lymphocytes were exposed to gamma rays in various doses (0 ∼ 40 Gy) and stimulated by PHA, then cultured for 24 to 96 hours. The activities of NKCF in the supernatants were assayed by MTT colorimetric method. The results showed: (1) The activity of NKCF was slightly inhibited by irradiation of 2.5 ∼ 40 Gy; (2) The activity of NKCF in the supernatants cultured for 48 to 96 hours is obviously higher than that for 24 hours. Both the irradiatiion doses and cultural periods had no interactiion on the changes of the production of NKCF. The radiation resistance of NK cells in the experiment is similar to other results. The tonsillar Nk cells activated in the state of chronic inflamation has higher radioresistance

  15. Alteration of membrane transductive mechanisms induced by ethanol in human lymphocyte cultures.

    Science.gov (United States)

    Fanò, G; Belia, S; Mariggiò, M A; Antonica, A; Agea, E; Spinozzi, F

    1993-03-01

    Ethanol, in millimolar concentrations, significantly modifies different transductive systems in human lymphocyte cultures. In particular, the presence of alcohol in the medium more than doubles the [Ca2+]i (from 70-90 to 200-250 nM), increasing Ca2+ fluxes from outside, and inhibits the active transport carried out by the calcium pump. The Ca2+ release from intracellular stores is not involved because 10 mM EGTA in the medium completely abolished the rise of [Ca2+]i. Since IP3 levels and cAMP concentrations are also involved in ethanol events (although with opposite effects), it seems that the alcohol may have a specific target on cell membranes (G-proteins) which influence many transductive pathways. PMID:8388700

  16. Adaptive differentiation of H-2- and Igh-restricted B lymphocyte in tetraparental bone marrow chimera

    International Nuclear Information System (INIS)

    Immunization of BALB/c mice with MOPC-104E myeloma protein induced idiotype-specific enhancing B cells that acted on anti-dextran antibody producing B cells. The enhancing cells have the surface phenotype of B cells. With the use of several H-2 or Igh congenic mice, it was found that the cooperation among B cells was controlled by both the major histocompatibility complex (MHC) and Igh. The capability to generate enhancing B cell activity was analyzed by using tetraparental bone marrow chimeras. (C57BL/6 X BALB/c)F1 mice, for example, were lethally irradiated and were reconstituted with C57BL/6 and BALB/c bone marrow cells. Nine to 12 wk after the reconstitution, the chimeras were immunized with the myeloma protein and were tested for their enhancing B cell activity. After the removal of C57BL/6 origin cells by treatment with anti-H-2b + complement, residual cells exhibited enhancing B cell activity on BALB.B, as well as BALB/c antidextran antibody response. This indicates that the generation of H-2-restricted, idiotype-specific enhancing B cell activity differentiated adaptively so as to recognize foreign MHC as self under chimeric conditions. On the other hand, splenic B cells treated with anti-H-2d + complement did not enhance the responses of BALB/c or BALB.B. Even in a chimeric environment, the B cells of C57BL/6 origin could not obtain the ability to generate enhancing B cell activity upon immunization of the idiotype. The results described here, taken in conjunction with our previous studies, suggest that the Ig heavy chain gene(s) predominantly control the Igh restriction properties of enhancing B cells, and the capability of MHC recognition by B cells is selected under chimeric conditions

  17. Expression profile of Eph receptors and ephrin ligands in healthy human B lymphocytes and chronic lymphocytic leukemia B-cells.

    Science.gov (United States)

    Alonso-C, Luis M; Trinidad, Eva M A; de Garcillan, Beatriz; Ballesteros, Monica; Castellanos, Milagros; Cotillo, Ignacio; Muñoz, Juan J; Zapata, Agustin G

    2009-03-01

    Increasing information relates some Eph receptors and their ligands, ephrins (EFN), with the immune system. Herein, we found that normal B-cells from peripheral blood (PB) and lymph nodes (LN) showed a differential expression of certain Eph/EFN members, some of them being modulated upon in vitro stimulation including EFNA1, EFNA4, EphB6 and EphA10. In contrast, PB CLL B-cells showed a more heterogeneous Eph/EFN profile than their normal PB B-cell counterparts, expressing Eph/EFN members frequently found within the LN and activated B-cells, specially EFNA4, EphB6 and EphA10. Two of them, EphB6 and EFNA4 were further related with the clinical course of CLL patients. EphB6 expression correlated with a high content of ZAP-70 mRNA and a poor prognosis. High serum levels of a soluble EFNA4 isoform positively correlated with increasing peripheral blood lymphocyte counts and lymphadenopathy. These findings suggest that Eph/EFN might be relevant in normal B-cell biology and could represent new potential prognostic markers and therapeutic targets for CLL. PMID:18819711

  18. Anomalous human behavior detection: an adaptive approach

    Science.gov (United States)

    van Leeuwen, Coen; Halma, Arvid; Schutte, Klamer

    2013-05-01

    Detection of anomalies (outliers or abnormal instances) is an important element in a range of applications such as fault, fraud, suspicious behavior detection and knowledge discovery. In this article we propose a new method for anomaly detection and performed tested its ability to detect anomalous behavior in videos from DARPA's Mind's Eye program, containing a variety of human activities. In this semi-unsupervised task a set of normal instances is provided for training, after which unknown abnormal behavior has to be detected in a test set. The features extracted from the video data have high dimensionality, are sparse and inhomogeneously distributed in the feature space making it a challenging task. Given these characteristics a distance-based method is preferred, but choosing a threshold to classify instances as (ab)normal is non-trivial. Our novel aproach, the Adaptive Outlier Distance (AOD) is able to detect outliers in these conditions based on local distance ratios. The underlying assumption is that the local maximum distance between labeled examples is a good indicator of the variation in that neighborhood, and therefore a local threshold will result in more robust outlier detection. We compare our method to existing state-of-art methods such as the Local Outlier Factor (LOF) and the Local Distance-based Outlier Factor (LDOF). The results of the experiments show that our novel approach improves the quality of the anomaly detection.

  19. Comparative analysis of chromosome aberrations induced in human lymphocytes in vitro by various types of ionizing radiations

    International Nuclear Information System (INIS)

    Certain problems of comparative analyses of radiation-induced dicentrics in human lymphocytes following various types of ionizing radiations are considered as follows: 1. Equations best fitting for dose-response kinetics; 2. Use of dicentrics for analysing the RBE of various types of radiations; 3. The relationship between RBE and LET as seen by the analysis of dicentrics. (author)

  20. [The dependence of the level of chromosome aberrations in human lymphocytes on the duration of their cultivation under ultraviolet irradiation].

    Science.gov (United States)

    Rushkovskiĭ, S R; Bezrukov, V F; Bariliak, I R

    1998-01-01

    The effect of duration of cultivation of lymphocytes of human UV-irradiated peripheral blood on the chromosomal aberration rate was studied. Under prolonged cultivation the more irradiated blood samples revealed higher level of chromosomal aberrations. The existence of UV-induced delayed chromosomal instability is supposed that may be found under prolonged cultivation. The mechanisms of this phenomenon are discussed.

  1. Functional and phenotypic changes in human lymphocytes after coincubation with Leishmania donovani in vitro

    DEFF Research Database (Denmark)

    Hviid, L; Sørensen, A L; Kharazmi, A;

    1990-01-01

    that the inhibition of the proliferative response to PHA by live L. donovani in vitro is associated with early processes in lymphocyte activation. Further studies on the inhibitory phenomena described may be of potential significance in the investigation of the suppressive mechanisms in human visceral leishmaniasis....

  2. Genotoxicity of the pesticide propoxur and its nitroso derivative, NO-propoxur, on human lymphocytes in vitro.

    Science.gov (United States)

    Gonzalez Cid, M; Loria, D; Matos, E

    1990-09-01

    The aim of this work was to investigate whether the pesticide propoxur and its nitroso derivative nitroso-propoxur increased the frequencies of sister-chromatid exchanges and micronuclei in human lymphocytes in vitro. The results show that both chemicals were genotoxic in the tested system.

  3. Dose-dependence of the chromosome aberration yield in a human lymphocyte culture after. gamma. -irradiation with high doses

    Energy Technology Data Exchange (ETDEWEB)

    Sevan' kaev, A.V. (Akademiya Meditsinskikh Nauk SSSR, Obninsk. Nauchno-Issledovatel' skij Inst. Meditsinskoj Radiologii)

    A study was made of the yield of chromosome aberrations in a human lymphocyte culture at the G/sub 0/ stage after /sup 60/Co-..gamma..-irradiation with doses of 5-12 Gy. It was shown that a linear-quadratic dependence of the aberration frequency observed with median doses became purely linear at high doses.

  4. The effect of ultraviolet radiation on early stages of activation of human lymphocytes: inhibition is independent of effects on DNA

    DEFF Research Database (Denmark)

    Castellanos, G; Owens, T; Rudd, C;

    1982-01-01

    Low doses (30-84 ergs/mm2, 1 erg = 10(7) J) of ultraviolet radiation (UV) caused severe inhibition of the proliferation of human lymphocytes in vitro. Greatest inhibition was produced when resting cells were irradiated immediately prior to stimulation with concanavalin A (Con A); this was true wh...

  5. The P2Z-purinoceptor of human lymphocytes: actions of nucleotide agonists and irreversible inhibition by oxidized ATP.

    OpenAIRE

    Wiley, J. S.; Chen, J. R.; Snook, M. B.; Jamieson, G P

    1994-01-01

    1. Extracellular adenosine triphosphate (ATP) is known to open a receptor-operated ion channel (P2Z class) in human lymphocytes which conducts a range of cationic permeants. The activity of a range of different agonists and inhibitors towards the P2Z-purinoceptor was investigated by measuring the agonist-induced influx of Ba2+ into fura-2 loaded lymphocytes. 2. The most potent agonist was 2' & 3'-0-(4-benzoylbenzoyl)-ATP (benzoylbenzoic ATP) which gave 2 fold greater maximum Ba2+ influx and h...

  6. The relationship between human T-lymphocyte subsets defined by monoclonal antibodies and by avidity differences to sheep erythrocytes

    DEFF Research Database (Denmark)

    Hokland, P; Hokland, M; Heron, I

    1982-01-01

    By E-rosette sedimentation procedures and fluorescence activated cell sorting of monoclonal antibody-coated T lymphocytes, we have investigated the relationship between the human T lymphocyte subsets defined by the monoclonal antibodies against the T4 and T8 antigens and those defined by avidity...... differences to sheep erythrocytes. Through a correlation was demonstrated between the T4+ (inducer) cells and the high avidity ("active") T cells and between the T8+ (suppressor) cells and low avidity T cells, these subsets were far from identical, and it is concluded that the application of monoclonal...

  7. Relation between clinical mature and immature lymphocyte cells in human peripheral blood and their spatial label free scattering patterns

    Science.gov (United States)

    Zhang, Lu; Zhao, Xin; Zhang, Zhenxi; Zhao, Hong; Chen, Wei; Yuan, Li

    2016-07-01

    A single living cell's light scattering pattern (LSP) in the horizontal plane, which has been denoted as the cell's "2D fingerprint," may provide a powerful label-free detection tool in clinical applications. We have recently studied the LSP in spatial scattering planes, denoted as the cell's "3D fingerprint," for mature and immature lymphocyte cells in human peripheral blood. The effects of membrane size, morphology, and the existence of the nucleus on the spatial LSP are discussed. In order to distinguish clinical label-free mature and immature lymphocytes, the special features of the spatial LSP are studied by statistical method in both the spatial and frequency domains. Spatial LSP provides rich information on the cell's morphology and contents, which can distinguish mature from immature lymphocyte cells and hence ultimately it may be a useful label-free technique for clinical leukemia diagnosis.

  8. A manual bead assay for the determination of absolute CD4+ and CD8+ lymphocyte counts in human immunodeficiency virus-infected individuals.

    OpenAIRE

    Carella, A V; Moss, M.W.; Provost, V; Quinn, T C

    1995-01-01

    CD4+ T lymphocytes are currently the most common surrogate marker indicating disease progression in individuals infected with human immunodeficiency virus (HIV). Since the cost of enumerating lymphocyte phenotypes is quite high, an inexpensive bead assay analyzed by light microscopy (cytosphere assay; Coulter Corporation, Hialeah, Fla.) was developed as an alternative method for counting CD4+ and CD8+ T lymphocytes. To evaluate the reliability of the cytosphere assay, heparinized blood was co...

  9. Antibody-dependent cell-mediated cytotoxicity (ADCC) toward human O+ red cells coated with anti-D antibody: comparison between lymphocyte and monocyte ADCC activity.

    OpenAIRE

    Sunada,Mitsutoshi; Suzuki, Shinya; Ota, Zensuke

    1985-01-01

    We investigated the antibody dependent cell-mediated cytotoxicity (ADCC) of lymphocytes and monocytes toward human O+ red cells coated with anti-D antibody using a 51Cr release assay. Lysis of sensitized red cells by lymphocytes occurred rapidly, but monocyte-mediated lysis occurred slowly. This difference might be due to postphagocytic 51Cr release by monocytes. ADCC of lymphocytes increased in proportion to the effector cell number, but large amounts of antibodies were required. In contrast...

  10. Frequency and distribution analysis of chromosomal translocations induced by x-ray in human lymphocytes

    International Nuclear Information System (INIS)

    The characteristic of ionizing radiation suggests that induced chromosomal damage in the form of translocations would appear to be randomly distributed. However, the outcome of tests performed in vitro and in vivo (irradiated individuals) are contradictories. The most translocation-related chromosomes, as far as some studies reveal on one hand, appear to be less involved in accordance with others. These data, together with those related to molecular mechanisms involved in translocations production suggest that in G0 -irradiated cells, the frequency and distribution of this kind of chromosomal rearrangement, does not take place at random. They seem to be affected by in-nucleus chromosome distribution, by each chromosome's DNA length and functional features, by the efficiency of DNA repair mechanisms, and by inter individual differences. The objective of this study was to establish the frequency pattern of each human chromosome involved in radio-induced translocations, as well as to analyze the importance the chromosome length, the activity of DNA polymerase- dependant repair mechanisms, and inter individual differences within the scope of such distribution. To achieve the goals, peripheral blood lymphocytes from healthy donors were irradiated in presence and absence of 2'-3' dideoxithimidine (ddThd), a Β - DNA polymerase inhibitor, which takes part in the base repair mechanism (B E R). The results showed that: The presence of ddThd during the irradiation increase the basal frequency of radioinduced translocations in 60 %. This result suggests that ddThd repair synthesis inhibition can be in itself a valid methodology for radiation-induced bases damage assessment, damage which if not BER-repaired may result in translocation-leading double strand breaks. A statistically significant correlation between translocation frequency and chromosome length, in terms of percentage of genome, has been noticed both in (basal) irradiation and in irradiation with ddThd inhibitor

  11. Autoradiographic detection of HPRT variants of human lymphocytes resistant to RNA synthesis inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Jones, I.M.; Zetterberg, G.; Strout, C.L.; Carrano, A.V.

    1985-01-01

    The feasibility of using RNA synthesis in freshly isolated, human peripheral blood lymphocytes to detect 6-thioguanine (TG)- and 8-azaguanine (AG)-resistant variants in an autoradiographic assay similar to that of Strauss and Albertini (1979) has been evaluated. In phytohemagglutinin (PHA)-stimulated cultures RNA synthesis and HPRT activity began well in advance of DNA synthesis and increased in parallel during the first 44 h of culture. Introduction of TG or AG with PHA at the beginning of culture completely inhibited DNA synthesis during the first 44 h and reduced RNA synthesis to low levels within 24 h. When TG or AG was added after cells had been in culture for 38 h, DNA synthesis was reduced quickly while RNA synthesis was inhibited more slowly. An autoradiographic assay is described in which freshly isolated lymphocytes are cultured with PHA for 24 h, with or without TG or AG, then labeled with (/sup 3/H)uridine for 1 h. TG-resistant and AG-resistant variant frequencies for 2 normal individuals and a Lesch-Nyhan individual were determined with this assay. The variant frequencies for the normal individuals ranged from 0.46 to 10.6 x 10/sup -5/ depending upon the selective conditions used. All the Lesch-Nyhan cells were resistant to 0.2 ..mu..M-2 mM AG; some were sensitive to 0.2 mM TG and most were sensitive to 2.0 mM TG. 24 references, 3 figures, 1 table.

  12. Melittin induced cytogenetic damage, oxidative stress and changes in gene expression in human peripheral blood lymphocytes.

    Science.gov (United States)

    Gajski, Goran; Domijan, Ana-Marija; Žegura, Bojana; Štern, Alja; Gerić, Marko; Novak Jovanović, Ivana; Vrhovac, Ivana; Madunić, Josip; Breljak, Davorka; Filipič, Metka; Garaj-Vrhovac, Vera

    2016-02-01

    Melittin (MEL) is the main constituent and principal toxin of bee venom. It is a small basic peptide, consisting of a known amino acid sequence, with powerful haemolytic activity. Since MEL is a nonspecific cytolytic peptide that attacks lipid membranes thus leading to toxicity, the presumption is that it could have significant therapeutic benefits. The aim was to evaluate the cyto/genotoxic effects of MEL in human peripheral blood lymphocytes (HPBLs) and the molecular mechanisms involved using a multi-biomarker approach. We found that MEL was cytotoxic for HPBLs in a dose- and time-dependent manner. It also induced morphological changes in the cell membrane, granulation and lysis of exposed cells. After treating HPBLs with non-cytotoxic concentrations of MEL, we observed increased DNA damage including oxidative DNA damage as well as increased formation of micronuclei and nuclear buds, and decreased lymphocyte proliferation determined by comet and micronucleus assays. The observed genotoxicity coincided with increased formation of reactive oxygen species, reduction of glutathione level, increased lipid peroxidation and phospholipase C activity, showing the induction of oxidative stress. MEL also modulated the expression of selected genes involved in DNA damage response (TP53, CDKN1A, GADD45α, MDM), oxidative stress (CAT, SOD1, GPX1, GSR and GCLC) and apoptosis (BAX, BCL-2, CAS-3 and CAS-7). Results indicate that MEL is genotoxic to HPBLs and provide evidence that oxidative stress is involved in its DNA damaging effects. MEL toxicity towards normal cells has to be considered if used for potential therapeutic purposes. PMID:26704293

  13. Bioprocess development for the cultivation of human T-lymphocytes in a clinical scale.

    Science.gov (United States)

    Bohnenkamp, H; Hilbert, U; Noll, T

    2002-01-01

    Adoptive transfer of large numbers of donor-derived T-lymphocytesmay offer a promising treatment of a variety of viral and malignant diseases. The key step in this approach is the ex vivo generation of sufficient quantities of these cells in a short time.We have investigated the influence of several important cultivation parameters on the proliferation of human T-lymphocytes to develop a large-scale fermentation process usingdifferent types of stirred bioreactors. Such systems offer manypotential advantages over the static culture systems commonlyused today.Peripheral blood mononuclear cells of healthy but CMV positive donors were stimulated with monoclonal antibodies (anti-CD3 and anti-CD28) and Interleukin-2. The influence of osmolality, Interleukin-2 concentration, pH, oxygen tension, feeding strategyand temperature on T-cell proliferation was investigated and theoptimised conditions were transferred to a novel stirred suspension bioreactor with an especially designed magnetic stirrbar to minimize the shear force (working volume 550 ml) and a standard stirred vessel (working volume 1000 ml).Preferable conditions for the cultivation of primary T-lymphocytes were an osmolality of 276-330 mOsmol kg(-1),an Interleukin-2 concentration of 100 U ml(-1), a pH rangeof 7.0 to 7.3, an oxygen tension of 5-50% and a temperature of 38.5 degrees C. After 238 h of cultivation 2.8 x 10(9) cells in the stirred vesseland 1.5 x 10(9) cells in the suspension bioreactor were obtained with a percentage of T-cells >94%. The specificity of the cells wasmaintained during cultivation as proven by IFN-gamma secretionafter exposure to a hCMV protein.

  14. Dose-rate effects for apoptosis and micronucleus formation in gamma-irradiated human lymphocytes

    International Nuclear Information System (INIS)

    We have compared dose-rate effects for γ-radiation-induced apoptosis and micronucleus formation in human lymphocytes. Long-term assessment of individual radiation-induced apoptosis showed little intraindividual variation but significant interindividual variation. The effectiveness of radiation exposure to cause apoptosis or micronucleus formation was reduced by low-dose-rate exposures, but the reduction was apparent at different dose rates for these two end points. Micronucleus formation showed a dose-rate effect when the dose rate was lowered to 0.29 cGy/min, but there was no accompanying cell cycle delay. A further increase in the dose-rate effect was seen at 0.15 cGy/min, but was now accompanied by cell cycle delay. There was no dose-rate effect for the induction of apoptosis until the dose rate was reduced to 0.15 cGy/min, indicating that the mechanisms or signals for processing radiation-induced lesions for these two end points must be different at least in part. There appear to be two mechanisms that contribute to the dose-rate effect for micronucleus formation. One of these does not affect binucleate cell frequency and occurs at dose rates higher than that required to produce a dose-rate effect for apoptosis, and one affects binucleate cell frequency, induced only at the very low dose rate which coincidentally produces a dose-rate effect for apoptosis. Since the dose rate at which cells showed reduced apoptosis as well as a further reduction in micronucleus formation was very low, we conclude that the processing of the radiation-induced lesions that induce apoptosis, and some micronuclei, is very slow in quiescent and PHA-stimulated lymphocytes, respectively. (author)

  15. Dose-rate effects for apoptosis and micronucleus formation in gamma-irradiated human lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Boreham, D.R.; Dolling, J.-A.; Maves, S.R. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Siwarungsun, N. [Chulalongkorn Univ., Bangkok (Thailand); Mitchel, R.E.J. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    2000-07-01

    We have compared dose-rate effects for {gamma}-radiation-induced apoptosis and micronucleus formation in human lymphocytes. Long-term assessment of individual radiation-induced apoptosis showed little intraindividual variation but significant interindividual variation. The effectiveness of radiation exposure to cause apoptosis or micronucleus formation was reduced by low-dose-rate exposures, but the reduction was apparent at different dose rates for these two end points. Micronucleus formation showed a dose-rate effect when the dose rate was lowered to 0.29 cGy/min, but there was no accompanying cell cycle delay. A further increase in the dose-rate effect was seen at 0.15 cGy/min, but was now accompanied by cell cycle delay. There was no dose-rate effect for the induction of apoptosis until the dose rate was reduced to 0.15 cGy/min, indicating that the mechanisms or signals for processing radiation-induced lesions for these two end points must be different at least in part. There appear to be two mechanisms that contribute to the dose-rate effect for micronucleus formation. One of these does not affect binucleate cell frequency and occurs at dose rates higher than that required to produce a dose-rate effect for apoptosis, and one affects binucleate cell frequency, induced only at the very low dose rate which coincidentally produces a dose-rate effect for apoptosis. Since the dose rate at which cells showed reduced apoptosis as well as a further reduction in micronucleus formation was very low, we conclude that the processing of the radiation-induced lesions that induce apoptosis, and some micronuclei, is very slow in quiescent and PHA-stimulated lymphocytes, respectively. (author)

  16. Inhibition of human peripheral blood lymphocyte function by protoporphyrin and longwave ultraviolet light

    Energy Technology Data Exchange (ETDEWEB)

    Barrett, K.E.; Yen, A.; Montisano, D.; Gigli, I.; Bigby, T.D. [Univ. of California, San Diego, CA (United States)

    1994-10-01

    Modulation of immunologic effector cells by exogenous photoactive substances has been advanced as an underlying mechanism for the efficacy of various photochemotherapeutic regimens. It is also possible that endogenous photosensitizers, such as protoporphyrin, could similarly modify the function of immune cell types. The authors examined the effects of protoporphyrin plus longwave UV light on the ability of human PBL to proliferate in response to mitogens. Noncytotoxic dosages of protoporphyrin plus UV light suppressed PHA-stimulated proliferation of both PBMC and enriched T cells. CD8{sup +} cells were more sensitive to this inhibitory effect than CD4{sup +} cells. The inhibitory effect was also observed when proliferation was induced by the combination of a phorbol ester and ionomycin. Inhibition of PBMC proliferation was associated with inhibition of IL-2 secretion but proliferation was not restored with exogenous IL-2. Instead, the effect of protoporphyrin plus UV light may be on IL-2R. Cells treated with protoporphyrin and UV light did not display the increase in CD25 and {beta}-chain of the IL-2R induced by PHA in control cells. In contrast to the effects of protoporphyrin and UV light on IL-2 and IL-2R {alpha}-chain protein expression, the accumulation of mRNA for these proteins induced by PHA was unaffected. None of the effects of protoporphyrin plus UV light on lymphocytes were observed in control experiments where cells were treated with either protoporphyrin or UV light alone. They conclude that biologically relevant dosages of protoporphyrin and UV light modify the function of circulating lymphocytes. 26 refs., 8 figs., 1 tab.

  17. Micronucleus assay in human lymphocytes as a bio dosimeter of in vivo acute and chronic exposures

    International Nuclear Information System (INIS)

    To assess the persistence over time of micronuclei (MN) in lymphocytes of cancer patients after radiotherapy and, consequently, to verify the suitability of MN test as a dosimeter for monitoring in vivo ionizing radiation damage, the cytokinesis-blocked MN assay was applied in peripheral blood lymphocytes of cervix and head and neck cancer patients (n = 34). The evaluation of data suggests that: 1) MN frequency increases linearly with the equivalent total-body absorbed dose (R2 = 0,9; P=0,015); 2) The distribution of the MN yields deviates significantly from Poisson with the increase of equivalent total-body dose (σ2/y = 1,14 mean value); 3) The comparison of spontaneous MN frequencies in healthy subjects with those in cancer patients, prior to radiotherapy, shows significant differences (p<0,01); and 4) It is observed a general decline in MN frequencies with time after radiotherapy, with considerable variations between patients. The kinetics of elimination of MN seems to follow a two-term exponential function, with a short and a long term. Patients with the highest equivalent total-body dose (total tumoral dose: 60-80 Gy) initially tend to have the fastest decline. At 6-18 months of follow-up time 11 of the 17 patients, evaluated 2-480 months post-treatment, showed higher frequencies of MN than their respective levels before radiation therapy, indicating persistence of radiation induced cytogenetic damage. Further studies modeling changes in chromosome aberrations with acute and chronic exposures should provide perspectives on biological dosimetry in accident situations in which there is a blood sampling delay and on biological monitoring of human populations exposed to ionizing radiation. (author)

  18. Early interferon-γ production in human lymphocyte subsets in response to nontyphoidal Salmonella demonstrates inherent capacity in innate cells.

    Directory of Open Access Journals (Sweden)

    Tonney S Nyirenda

    Full Text Available BACKGROUND: Nontyphoidal Salmonellae frequently cause life-threatening bacteremia in sub-Saharan Africa. Young children and HIV-infected adults are particularly susceptible. High case-fatality rates and increasing antibiotic resistance require new approaches to the management of this disease. Impaired cellular immunity caused by defects in the T helper 1 pathway lead to intracellular disease with Salmonella that can be countered by IFNγ administration. This report identifies the lymphocyte subsets that produce IFNγ early in Salmonella infection. METHODOLOGY: Intracellular cytokine staining was used to identify IFNγ production in blood lymphocyte subsets of ten healthy adults with antibodies to Salmonella (as evidence of immunity to Salmonella, in response to stimulation with live and heat-killed preparations of the D23580 invasive African isolate of Salmonella Typhimurium. The absolute number of IFNγ-producing cells in innate, innate-like and adaptive lymphocyte subpopulations was determined. PRINCIPAL FINDINGS: Early IFNγ production was found in the innate/innate-like lymphocyte subsets: γδ-T cells, NK cells and NK-like T cells. Significantly higher percentages of such cells produced IFNγ compared to adaptive αβ-T cells (Student's t test, P<0.001 and ≤0.02 for each innate subset compared, respectively, with CD4(+- and CD8(+-T cells. The absolute numbers of IFNγ-producing cells showed similar differences. The proportion of IFNγ-producing γδ-T cells, but not other lymphocytes, was significantly higher when stimulated with live compared with heat-killed bacteria (P<0.0001. CONCLUSION/SIGNIFICANCE: Our findings indicate an inherent capacity of innate/innate-like lymphocyte subsets to produce IFNγ early in the response to Salmonella infection. This may serve to control intracellular infection and reduce the threat of extracellular spread of disease with bacteremia which becomes life-threatening in the absence of protective antibody

  19. Functional role of HLA class I cell-surface molecules in human T-lymphocyte activation and proliferation.

    OpenAIRE

    Taylor, D S; Nowell, P C; Kornbluth, J

    1986-01-01

    This investigation addressed the role of major histocompatibility complex-encoded class I molecules in the activation and proliferation of human lymphocytes. We studied the effect of antibodies specific for HLA-A and HLA-B locus gene products on mitogen-stimulated peripheral blood mononuclear cell (PBMC) subpopulations. Three individually derived, well-characterized anti-HLA class I monoclonal antibodies were demonstrated to inhibit the proliferation of human PBMC stimulated by either OKT3 or...

  20. Effects of ISS equivalent ionizing radiation dose on Human T-lymphocytes

    Science.gov (United States)

    Meloni, Maria Antonia; Pani, Giuseppe; Benotmane, Rafi; Mastroleo, Felice; Aboul-El-Ardat, Khalil; Janssen, Ann; Leysen, Liselotte; Vanhavere, Filip; Leys, Natalie; Galleri, Grazia; Pippia, Proto; Baatout, Sarah

    One of the objectives of the current international space programs is to investigate the effects of cosmic environment on Humans. It is known that during a long exposure to the space conditions, including ionizing radiations and microgravity, the immune system of the astronauts is impaired. In past years several experiments were performed to identify responsible factors of in vitro mitogenic activation process in human T-lymphocytes under simulated microgravity effect and during dedicated space missions. It come out that the lack of immune response in microgravity occurs at the cellular and molecular level. In order to evaluate effects on pure primary T-lymphocytes from peripheral blood exposed to International Space Station (ISS)-like ionizing radiation, we applied a mixture of Cesium-137, as representative of low energy particles, and Californium-252, as representative of hight energy particles, with rate similar to those monitored inside the ISS during previous space mission (Goossens et all. 2006). This facility is available at SCK•CEN (Belgium) (Mastroleo et al., 2009). Although the dose received by the cells was relatively low, flow cytometry analysis 24 hours after irradiation showed a decrease in cell viability coupled with the increase of the caspase-3 activity. However, Bcl-2 activity did not seem to be affected by the radiation. Furthermore, activation of cells induced an increase of the cell size and alteration of cellular morphology. Cell cycle as well as 8-oxo-G were also modified upon radiation and activation. Gene expression analysis shows a modulation of genes rather as a consequence of exposure than with the activation status. 330 genes have been identified to be significantly modulated in function of the time and have been grouped in four different cluster representing significant expression profiles. Preliminary functional analysis shows mainly genes involved in the immune response and inflammatory diseases as well as oxidative stress and

  1. Erythropoietin receptor is expressed on human peripheral blood T and B lymphocytes and monocytes and is modulated by recombinant human erythropoietin treatment.

    Science.gov (United States)

    Lisowska, Katarzyna A; Debska-Slizień, Alicja; Bryl, Ewa; Rutkowski, Bolesław; Witkowski, Jacek M

    2010-08-01

    Erythropoietin receptor (EPO-R) appears on the cell surface in the early stages of erythropoiesis. It has also been found on endothelial cells and polymorphonuclear leukocytes, suggesting erythropoietin (EPO) role beyond erythropoiesis itself. Earlier reports have shown that treatment with recombinant human erythropoietin (rhEPO) in chronic renal failure (CRF) patients improves interleukin-2 production and restores the T lymphocyte function. We decided to investigate possible expression of EPO-R on circulating peripheral blood lymphocytes and monocytes of CRF patients in order to assess the possibility of rhEPO direct action on these cells. Flow cytometry was used for detection and quantification of EPO-R, and reverse transcription polymerase chain reaction for detection of the EPO receptor mRNA. Our results show for the first time the existence of EPO-R on cell surface of human T and B lymphocytes and monocytes as well as at the transcriptional activity of the EPO-R gene in these cells, both in healthy and CRF individuals. We have also found significant differences between the numbers of EPO-R molecules on T and B lymphocytes of CRF patients not treated and treated with rhEPO and healthy control. Discovery of EPO-R expression on human lymphocytes suggests that EPO is probably able to directly modulate some signaling pathways important for these cells. PMID:20528849

  2. Protective Effect of Prolactin against Methylmercury-Induced Mutagenicity and Cytotoxicity on Human Lymphocytes

    Directory of Open Access Journals (Sweden)

    Liz Carmem Silva-Pereira

    2014-09-01

    Full Text Available Mercury exhibits cytotoxic and mutagenic properties as a result of its effect on tubulin. This toxicity mechanism is related to the production of free radicals that can cause DNA damage. Methylmercury (MeHg is one of the most toxic of the mercury compounds. It accumulates in the aquatic food chain, eventually reaching the human diet. Several studies have demonstrated that prolactin (PRL may be differently affected by inorganic and organic mercury based on interference with various neurotransmitters involved in the regulation of PRL secretion. This study evaluated the cytoprotective effect of PRL on human lymphocytes exposed to MeHg in vitro, including observation of the kinetics of HL-60 cells (an acute myeloid leukemia lineage treated with MeHg and PRL at different concentrations, with both treatments with the individual compounds and combined treatments. All treatments with MeHg produced a significant increase in the frequency of chromatid gaps, however, no significant difference was observed in the chromosomal breaks with any treatment. A dose-dependent increase in the mitotic index was observed for treatments with PRL, which also acts as a co-mitogenic factor, regulating proliferation by modulating the expression of genes that are essential for cell cycle progression and cytoskeleton organization. These properties contribute to the protective action of PRL against the cytotoxic and mutagenic effects of MeHg.

  3. Mesenchymal stem cells derived from human placenta suppress allogeneic umbilical cord blood lymphocyte proliferation

    Institute of Scientific and Technical Information of China (English)

    Chang Dong LI; Wei Yuan ZHANG; He Lian LI; Xiao Xia JIANG; Yi ZHANG; Pei Hsien TANG; Ning MAO

    2005-01-01

    Human placenta-derived mononuclear cells (MNC) were isolated by a Percoll density gradient and cultured in mesenchymal stem cell (MSC) maintenance medium.The homogenous layer of adherent cells exhibited a typical fibroblastlike morphology,a large expansive potential,and cell cycle characteristics including a subset of quiescent cells.In vitro differentiation assays showed the tripotential differentiation capacity of these cells toward adipogenic,osteogenic and chondrogenic lineages.Flow cytometry analyses and immunocytochemistry stain showed that placental MSC was a homogeneous cell population devoid of hematopoietic cells,which uniformly expressed CD29,CD44,CD73,CD 105,CD166,laminin,fibronectin and vimentin while being negative for expression of CD31,CD34,CD45 and α-smooth muscle actin.Most importantly,immuno-phenotypic analyses demonstrated that these cells expressed class I major histocompatibility complex (MHC-Ⅰ),but they did not express MHC-Ⅱ molecules.Additionally these cells could suppress umbilical cord blood (UCB) lymphocytes proliferation induced by cellular or nonspecific mitogenic stimuli.This strongly implies that they may have potential application in allograft transplantation.Since placenta and UCB are homogeneous,the MSC derived from human placenta can be transplanted combined with hematopoietic stem cells (HSC) from UCB to reduce the potential graft-versus-host disease (GVHD) in recipients.

  4. Factors influencing the kinetics of heat shock protein expression in human lymphocytes

    International Nuclear Information System (INIS)

    Full text: All organisms, from bacteria to humans, respond to various forms of environmental stresses by inducing the synthesis of a highly conserved set of proteins, the heat shock proteins (hsps) or stress proteins. Many hsps are also expressed constitutively at lower levels and in this capacity perform essential cellular functions including protein trafficking and chaperone activity. Our approach was to follow the kinetics of hsp expression in both control and heat shocked human peripheral lymphocytes from young and old individuals. Heat shock treatment was at 42 deg C for 1 h and samples were taken at various time points during heat shock and following recovery at 37 deg C. Samples were analysed using both 35[S] methionine-labelling and western blot analysis. In addition, we investigated the possible role of phosphorylation in modulating the activity of hsps utilising phospho-specific antibodies in western blot analysis as well as metabolic 32[P] phosphate-labelling. Our study showed that hsp expression is elevated at the end of heat shock treatment, but can be seen at a lower level from 30 min during heat shock. The time taken to reach maximal induction varied for different hsps. For example hsp 70 appeared to peak at 3 h following recovery, which is consistent with previous findings. The results from western blots using phospho-specific antibodies and also the de novo synthesis of 32[P] phosphate-labelled hsps are preliminary and experiments are currently in progress

  5. Metallothionein 1 Isoform Gene Expression Induced by Cadmium in Human Peripheral Blood Lymphocytes

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    To study the gene expression of metallothionein 1 (MT-1) isoforms in human peripheral blood lymphocytes (HPBLs). Methods The expression of mRNA representing the seven active MT-1 genes was determined in HPBLs by quantitative RT-PCR before and after exposure to cadmium. Results Basal expressions of MT-1X, and MT-1A in HPBLs were similar to expression of housekeeping gene. In contrast, the basal gene expressions of MT-1H, 1F, 1E, and 1G were a little transcripts in human HPBLs. No signal was detected for MT-1B. There was a sex difference (P<0.05). in basal gene expression of MT-1E. The levels of gene expression of MT-1A, 1E, 1F, 1G, 1H, and 1X increased, but the level of MT-1B did not increase after exposure to cadmium. Conclusions Gene expressions of MT-1G, MT-1H, MT-1F, and MT-1X in HPBLs can be used as a potential biomarker of cadmium exposure.

  6. Studies on the cytotoxicity of diamond nanoparticles against human cancer cells and lymphocytes.

    Science.gov (United States)

    Adach, Kinga; Fijalkowski, Mateusz; Gajek, Gabriela; Skolimowski, Janusz; Kontek, Renata; Blaszczyk, Alina

    2016-07-25

    Detonation nanodiamonds (DND) are a widely studied group of carbon nanomaterials. They have the ability to adsorb a variety of biomolecules and drugs onto their surfaces, and additionally their surfaces may be subjected to chemical functionalization by covalent bonds. We present a procedure for the purification and surface oxidation of diamond nanoparticles, which were then tested by spectroscopic analysis such as ATR-FTIR, Raman spectroscopy, and thermogravimetric analysis. We also examined the zeta potential of the tested material. Analysis of the cytotoxic effect of nanodiamonds against normal lymphocytes derived from human peripheral blood, the non-small cell lung cancer cell line (A549) and the human colorectal adenocarcinoma cell line (HT29) was performed using MTT colorimetric assay. Evaluation of cell viability was performed after 1-h and 24-h treatment with the tested nanoparticles applied at concentrations ranging from 1 μg/ml to 100 μg/ml. We found that the survival of the examined cells was strongly associated with the presence of serum proteins in the growth medium. The incubation of cells with nanodiamonds in the presence of serum did not exert a significant effect on cell survival, while the cell treatment in a serum-free medium resulted in a decrease in cell survival compared to the negative control. The role of purification and functionalization of nanodiamonds on their cytotoxicity was also demonstrated. PMID:27270448

  7. Development of a serum-free medium for in vitro expansion of human cytotoxic T lymphocytes using a statistical design

    Directory of Open Access Journals (Sweden)

    Lee Gyun

    2010-09-01

    Full Text Available Abstract Background Serum-containing medium (SCM, which has a number of poorly defined components with varying concentrations, hampers standardization of lymphocyte cultures. In order to develop a serum-free medium (SFM for the expansion of human lymphocytes from peripheral blood mononuclear cells (PBMCs, a statistical optimization approach based on a fractional factorial method and a response surface method was adopted. A basal medium was prepared by supplementing RPMI1640 medium with insulin, albumin, ferric citrate, ethanolamine, fatty acids, glutamine, sodium pyruvate, 2-mercaptoethanol, 1-thioglycerol, nonessential amino acids, and vitamins. We identified additional positive determinants and their optimal concentrations for cell growth through a statistical analysis. Results From a statistical analysis using the fractional factorial method, cholesterol and polyamine supplement were identified as positive determinants for cell growth. Their optimal concentrations were determined by the response surface method. The maximum viable cell concentration in the developed SFM was enhanced by more than 1.5-fold when compared to that in RPMI1640 supplemented with 10% fetal bovine serum (FBS. Furthermore, a cytotoxicity assay and an enzyme-linked immunospot assay revealed that the effector function of cytotoxic T lymphocytes generated from PBMCs grown in SFM, by stimulation of peptide-presenting dendritic cells, was retained or even better than that in SCM. Conclusions The use of a developed SFM with cholesterol and polyamine supplement for human lymphocyte culture resulted in better growth without loss of cellular function when compared to SCM.

  8. Induction of micronuclei by X-radiation in human, mouse and rat peripheral blood lymphocytes

    International Nuclear Information System (INIS)

    The radiosensitivity of human, mouse and rat peripheral blood lymphocytes (PBLs) was compared by analyzing micronuclei (MN) in cyto-chalasin B-induced binucleated (BN) cells. For each species and dose 4-ml aliquots of whole blood were X-irradiated to obtain doses of 38, 75, 150 or 300 cGy. Controls were sham-irradiated. After exposure to X-rays, mononuclear leukocytes were isolated using density gradients and cultured in RPMI 1640 medium containing phytohemagglutinin to stimulate mitogenesis. At 21 h cytochalasin B was added to produce BN PBLs, and all cultures were harvested at 52 h post-initiation using a cyto-centrifuge. Significant dose-dependent increases in the percentage of micronucleated cells and the number of MN per BN cell were observed in all three species. The linear-quadratic regression curves for the total percentage of micronucleated cells for the three species were similar; however, the curve for the mouse PBLs had a larger quadratic component than either of the curves for the rat or the human PBLs. Although the correlation between the percentage of cells with MN and those with chromosome aberrations was high (r2>0.95), the mouse and rat PBLs were over twice as efficient as human PBLs in forming MN from presumed acentric fragments. These data indicate that the induction of MN in BN cells following ionizing radiation is similar in human, rat and mouse PBLs, but care must be taken in using the MN results to predict frequencies of cells with chromosomal aberrations. (author). 19 refs.; 3 figs.; 2 tabs

  9. Induction of micronuclei by X-radiation in human, mouse and rat peripheral blood lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Erexson, G.L.; Bryant, M.F. (Environmental Health Research and Testing, Inc. Research Triangle Park, NC (USA)); Kligerman, A.D. (U.S. Environmental Protection Agency, Research Triangle Park, NC (USA). Mutagenesis and Cellular Toxicology Branch); Sontag, M.R.; Halperin, E.C. (Duke University Medical center, Durham, NC (USA). Division of Radiation Oncology)

    1991-10-01

    The radiosensitivity of human, mouse and rat peripheral blood lymphocytes (PBLs) was compared by analyzing micronuclei (MN) in cyto-chalasin B-induced binucleated (BN) cells. For each species and dose 4-ml aliquots of whole blood were X-irradiated to obtain doses of 38, 75, 150 or 300 cGy. Controls were sham-irradiated. After exposure to X-rays, mononuclear leukocytes were isolated using density gradients and cultured in RPMI 1640 medium containing phytohemagglutinin to stimulate mitogenesis. At 21 h cytochalasin B was added to produce BN PBLs, and all cultures were harvested at 52 h post-initiation using a cyto-centrifuge. Significant dose-dependent increases in the percentage of micronucleated cells and the number of MN per BN cell were observed in all three species. The linear-quadratic regression curves for the total percentage of micronucleated cells for the three species were similar; however, the curve for the mouse PBLs had a larger quadratic component than either of the curves for the rat or the human PBLs. Although the correlation between the percentage of cells with MN and those with chromosome aberrations was high (r{sup 2}>0.95), the mouse and rat PBLs were over twice as efficient as human PBLs in forming MN from presumed acentric fragments. These data indicate that the induction of MN in BN cells following ionizing radiation is similar in human, rat and mouse PBLs, but care must be taken in using the MN results to predict frequencies of cells with chromosomal aberrations. (author). 19 refs.; 3 figs.; 2 tabs.

  10. Anticlastogenic Effect of Redistilled Cow's Urine Distillate in Human Peripheral Lymphocytes Challenged With Manganese Dioxide and Hexavalent Chromium

    Institute of Scientific and Technical Information of China (English)

    DIPANWITA DUTTA; S.SARAVANA DEVI; K. KRISHNAMURTHI; T. CHAKRABARTI

    2006-01-01

    Objective To study the anticlastogenic effect of redistilled cow's urine distillate (RCUD) in human peripheral lymphocytes (HLC) challenged with manganese dioxide and hexavalent chromium. Methods The anticlastogenic activity of redistilled cow's urine distillate was studied in human polymorphonuclear leukocytes (HPNLs) and human peripheral lymphocytes in vitro challenged with manganese dioxide and hexavalent chromium as established genotoxicants and clastogens which could cause induction of DNA strand break, chromosomal aberration and micronucleus. Three different levels of RCUD: 1 μL/mL, 50 μL/mL and 100μL/mL, were used in the study. Results Manganese dioxide and hexavalent chromium caused statistically significant DNA strand break, chromosomal aberration and micronucleus formation, which could be protected by redistilled cow's urine distillate. Conclusion The redistilled cow's urine distillate posseses strong antigenotoxic and anticlastogenic properties against HPNLs and HLC treated with Cr+6 and MnO2. This property is mainly due to the antioxidants present in RCUD.

  11. Exposure of human nasal epithelial cells to formaldehyde does not lead to DNA damage in lymphocytes after co-cultivation.

    Science.gov (United States)

    Neuss, Simone; Moepps, Barbara; Speit, Günter

    2010-07-01

    We performed in vitro co-cultivation experiments with primary human nasal epithelial cells (HNEC) and isolated lymphocytes to investigate whether reactive formaldehyde (FA) can be passed on from nasal epithelial cells (site of first contact) to lymphocytes located in close proximity and induce DNA damage in these cells. A modified comet assay was used as a sensitive method for the detection of FA-induced DNA-protein cross links (DPX) because DPX are the most relevant type of FA-induced DNA damage. Our results clearly indicate that co-cultivation of lymphocytes with HNEC exposed to FA for 1 h causes a concentration-related induction of DPX in lymphocytes when co-cultivation takes place in the exposure medium. However, when the exposure medium is changed after FA treatment of HNEC and before lymphocytes are added, no induction of DPX is measured in lymphocytes even after exposure of HNEC to high FA concentrations (300 microM) and extended co-cultivation (4 h). Direct measurement of FA in the cell culture medium by a sensitive fluorescent detection kit indicated that FA is actually not released even from highly exposed cells into the cell culture medium. These results suggest that FA that has entered nasal epithelial cells is not released and does not damage other cells in close proximity to the epithelial cells. If these results also apply to the in vivo situation, FA would only be genotoxic towards directly exposed cells (site of first contact) and there should be no significant delivery of inhaled FA to other cells and distant sites. Our results do not support a recently proposed hypothetic mechanism for FA-induced leukaemia by damaging circulating haematopoietic stem cells or haematopoietic progenitor cells in nasal passages, which then travel to the bone marrow and become initiated leukaemic stem cells.

  12. Radiation-induced bystander effect in healthy G{sub 0} human lymphocytes: Biological and clinical significance

    Energy Technology Data Exchange (ETDEWEB)

    Belloni, Paola; Latini, Paolo [Department of Agrobiology and Agrochemistry, University of Tuscia, Via San Camillo De Lellis, I-01100 Viterbo (Italy); Palitti, Fabrizio, E-mail: palitti@unitus.it [Department of Agrobiology and Agrochemistry, University of Tuscia, Via San Camillo De Lellis, I-01100 Viterbo (Italy)

    2011-08-01

    To study the bystander effects, G{sub 0} human peripheral blood lymphocytes were X-irradiated with 0.1, 0.5 and 3 Gy. After 24 h, cell-free conditioned media from irradiated cultures were transferred to unexposed lymphocytes. Following 48 h of medium transfer, viability, induction of apoptosis, telomere shortening, reactive oxygen species (ROS) levels and micronuclei (after stimulation) were analyzed. A statistically significant decrement in cell viability, concomitant with the loss of mitochondrial membrane potential, telomere shortening, increases in hydrogen peroxide (H{sub 2}O{sub 2}) and superoxide anion (O{sub 2}{sup -}) with depletion of intracellular glutathione (GSH) level, and higher frequencies of micronuclei, were observed in bystander lymphocytes incubated with medium from 0.5 and 3 Gy irradiated samples, compared to lymphocytes unexposed. Furthermore, no statistically significant difference between the response to 0.5 and 3 Gy of irradiation in bystander lymphocytes, was found. However, when lymphocytes were irradiated with 0.1 Gy, no bystander effect with regard to viability, apoptosis, telomere length, and micronuclei was observed, although a high production of ROS level persisted. Radiation in the presence of the radical scavenger dimethyl sulfoxide (DMSO) suppressed oxidative stress induced by 3 Gy of X-rays with the effective elimination of bystander effects, suggesting a correlation between ROS and bystander signal formation in irradiated cells. The data propose that bystander effect might be mostly due to the reactions of radiation induced free radicals on DNA, with the existence of a threshold at which the bystander signal is not operative (0.1 Gy dose of X-rays). Our results may have clinical implications for health risk associated with radiation exposure.

  13. Genetic determination of chromosomal radiosensitivities in G0- and G2-phase human lymphocytes

    International Nuclear Information System (INIS)

    Background and purpose: The radiosensitivity of human lymphocytes measured using a G0- or G2-assay has been linked with an individual's risk of developing normal tissue complications following radiotherapy. This study was performed to increase basic knowledge of the genetics of the human radiation response, and chromosomal aberration induction in particular. Materials and methods: The study was carried out with blood samples taken from 15 monozygotic twin pairs. G0-assay was performed for cells irradiated with 6 Gy counting only deletions and G2-assay for cells irradiated with 0.5 Gy scoring only chromatid breaks. Results: The mean number of deletions measured at 6 Gy for all 30 samples using the G0-assay amounted to 2.96 ± 0.37 (means ± SD), which corresponds to a coefficient of variation (CV) of 13%. There is a highly significant intra-pair correlation for this number among twins (r 2 = 0.911) demonstrating that this parameter is mostly determined by genetic factors. According to the mean number of deletions, a theoretical classification based on the definition =MV + SD as sensitive was made, identifying two pairs as sensitive or resistant, respectively, while nine were normal and two pairs are intermediate. For chromatid breaks measured at 0.5 Gy with the G2-assay the mean number was 1.35 ± 0.42 (means ± SD) corresponding to a CV of 31%. There was again a strong intra-pair correlation among twins with r 2 = 0.837 showing that this sensitivity is also determined mostly by genetic factors. There was, however, no inter-assay correlation between the G0- and G2-sensitivity (r 2 = 0.006) demonstrating that these two sensitivities depend on different genetic factors. Conclusion: The chromosomal radiosensitivity of lymphocytes as defined by G0- or G2-assay is largely determined by different genetic factors, which may allow the use of genetic profiling as an indicator of the respective individual radiosensitivity

  14. Human Adaptation and the Ingenuity Gap

    Directory of Open Access Journals (Sweden)

    Thomas Homer-Dixon

    2003-07-01

    Full Text Available I have been working for many years on the problem of adaptation: how societies or organisms, species, or systems of various kinds adapt to complex and rapid change. In this paper, I will outline my theories and my thinking about adaptation as summarized in the book, The Ingenuity Gap. I will also highlight five aspects of education for the future: education for complexity and what that means; education for reconnection to the micro and macro scales around us; education that increases our respect for experiential knowledge; education that will encourage a recognition of our connectivity through time, from the present into the future; and finally, education to broaden our conception of values. I’ll touch on each one of these points in my presentation today.

  15. Human gene transfer: Characterization of human tumor-infiltrating lymphocytes as vehicles for retroviral-mediated gene transfer in man

    International Nuclear Information System (INIS)

    Tumor-infiltrating lymphocytes (TILs) are cells generated from tumor suspensions cultured in interleukin 2 that can mediate cancer regression when adoptively transferred into mice or humans. Since TILs proliferate rapidly in vitro, recirculate, and preferentially localize at the tumor site in vivo, they provide an attractive model for delivery of exogenous genetic material into man. To determine whether efficient gene transfer into TILs is feasible. The authors transduced human TILs with the bacterial gene for neomycin-resistance (NeoR) using the retroviral vector N2. The transduced TIL populations were stable and polyclonal with respect to the intact NeoR gene integration and expressed high levels of neomycin phosphotransferase activity. The NeoR gene insertion did not alter the in vitro growth pattern and interleukin 2 dependence of the transduced TILs. Analyses of T-cell receptor gene rearrangement for β- and γ-chain genes revealed the oligoclonal nature of the TIL populations with no major change in the DNA rearrangement patterns or the levels of mRNA expression of the β and γ chains following transduction and selection of TILs in the neomycin analog G418. Human TILs expressed mRNA for tumor necrosis factors (α and β) and interleukin 2 receptor P55. This pattern of cytokine-mRNA expression was not significantly altered following the transduction of TILs. The studies demonstrate the feasibility of TILs as suitable cellular vehicles for the introduction of therapeutic genes into patients receiving autologous TILs

  16. B Lymphocyte Stimulator (BLyS is expressed in human adipocytes in vivo and is related to obesity but not to insulin resistance.

    Directory of Open Access Journals (Sweden)

    Nike Müller

    Full Text Available Inflammation and metabolism have been shown to be evolutionary linked and increasing evidence exists that pro-inflammatory factors are involved in the pathogenesis of obesity and type 2 diabetes. Until now, most data suggest that within adipose tissue these factors are secreted by cells of the innate immune system, e. g. macrophages. In the present study we demonstrate that B lymphocyte stimulator (BLyS is increased in human obesity. In contrast to several pro-inflammatory factors, we found the source of BLyS in human adipose tissue to be the adipocytes rather than immune cells. In grade 3 obese human subjects, expression of BLyS in vivo in adipose tissue is significantly increased (p<0.001. Furthermore, BLyS serum levels are elevated in grade 3 human obesity (862.5+222.0 pg/ml vs. 543.7+60.7 pg/ml in lean controls, p<0.001 and are positively correlated to the BMI (r = 0.43, p<0.0002. In the present study, bariatric surgery significantly altered serum BLyS concentrations. In contrast, weight loss due to a very-low-calorie-formula-diet (800 kcal/d had no such effect. To examine metabolic activity of BLyS, in a translational research approach, insulin sensitivity was measured in human subjects in vivo before and after treatment with the human recombinant anti-BLyS antibody belimumab. Since BLyS is known to promote B-cell proliferation and immunoglobulin secretion, the present data suggest that adipocytes of grade 3 obese human subjects are able to activate the adaptive immune system, suggesting that in metabolic inflammation in humans both, innate and adaptive immunity, are of pathophysiological relevance.

  17. Genomic instability after targeted irradiation of human lymphocytes: Evidence for inter-individual differences under bystander conditions

    International Nuclear Information System (INIS)

    Environmental 222radon exposure is a human health concern, and many studies demonstrate that very low doses of high LET α-particle irradiation initiate deleterious genetic consequences in both irradiated and non-irradiated bystander cells. One consequence, radiation-induced genomic instability (RIGI), is a hallmark of tumorigenesis and is often assessed by measuring delayed chromosomal aberrations. We utilised a technique that facilitates transient immobilization of primary lymphocytes for targeted microbeam irradiation and have reported that environmentally relevant doses, e.g. a single 3He2+ particle traversal to a single cell, are sufficient to induce RIGI. Herein we sought to determine differences in radiation response in lymphocytes isolated from five healthy male donors. Primary lymphocytes were irradiated with a single particle per cell nucleus. We found evidence for inter-individual variation in radiation response (RIGI, measured as delayed chromosome aberrations). Although this was not highly significant, it was possibly masked by high levels of intra-individual variation. While there are many studies showing a link between genetic predisposition and RIGI, there are few studies linking genetic background with bystander effects in normal human lymphocytes. In an attempt to investigate inter-individual variation in the induction of bystander effects, primary lymphocytes were irradiated with a single particle under conditions where fractions of the population were traversed. We showed a marked genotype-dependent bystander response in one donor after exposure to 15% of the population. The findings may also be regarded as a radiation-induced genotype-dependent bystander effect triggering an instability phenotype.

  18. PKCθ is required for the activation of human T lymphocytes induced by CD43 engagement

    International Nuclear Information System (INIS)

    The turnover of phosphoinositides leading to PKC activation constitutes one of the principal axes of intracellular signaling. In T lymphocytes, the enhanced and prolonged PKC activation resulting from the engagement of the TcR and co-receptor molecules ensures a productive T cell response. The CD43 co-receptor promotes activation and proliferation, by inducing IL-2 secretion and CD69 expression. CD43 engagement has been shown to promote phosphoinositide turnover and DAG production. Moreover, PKC activation was found to be required for the activation of the MAP kinase pathway in response to CD43 ligation. Here we show that CD43 engagement led to the membrane translocation and enzymatic activity of specific PKC isoenzymes: cPKC (α/β), nPKC (ε and θ), aPKC (ζ) and PKCμ. We also show that activation of PKCθ resulting from CD43 ligation induced CD69 expression through an ERK-dependent pathway leading to AP-1, NF-κB activation and an ERK independent pathway promoting NFAT activation. Together, these data suggest that PKCθ plays a critical role in the co-stimulatory functions of CD43 in human T cells

  19. Induction of chromosome aberration in human lymphocytes and its dependence on X ray energy

    International Nuclear Information System (INIS)

    The variations of dose response with X ray energy observed with the human lymphocyte dicentric assay is examined. In order to determine reliably the initial slopes (RBEm) many cells need to be analysed at low doses. Insufficient analysis may explain some reported interlaboratory differences in fitted dose-response coefficients. One such discrepancy at 150 kVp, E(mean) = 70 keV is examined. Data are also presented for an X ray spectrum of 80 kVp, E(mean) = 58 keV. Over the photon energy range 20 keV X rays to 1.25 MeV gamma rays RBEm varies by about a factor of 5, with the lower energies being more effective. This is consistent with microdosimetric theory. By contrast, in radiological protection a radiation weighting factor of 1.0 is assumed for all photons when assessing the risk of inducing cancer at low doses. The measured variations of biological effect with photon energy have led to suggestions that the lower energies, as used for some diagnostic radiology, carry a greater risk per unit dose than is normally assumed by those involved in radiological protection. Interpretation of the data reported in this paper does not support this view. (author)

  20. Interaction between nitric oxide and subsets of human T lymphocytes with differences in glutathione metabolism

    Science.gov (United States)

    Roozendaal, Ramon; Kauffman, Henk F; Dijkhuis, Anne-Jan; Ommen, Elisabeth T V; Postma, Dirkje S; De Monchy, Jan G R; Vellenga, Edo

    2002-01-01

    Nitric oxide (NO) modulates human T-lymphocyte responses through several mechanisms. In the current study we show that interactions between NO and glutathione (GSH) metabolism are related to the selective persistent inhibition of interferon-γ (IFN-γ) production by NO, which we previously identified. T cells were exposed to NO using the NO-donor compound Spermine-nonoate (Sper) and activated using anti-CD3 plus anti-CD28 monoclonal antibodies. Persistent inhibition of IFN-γ by Sper was prevented by addition of the GSH precursor l-cysteine, which inhibits Sper induced GSH depletion. Subsets of cells were either susceptible (GSHlow) or resistant (GSHhigh) to NO-induced GSH depletion. The GSHlow subset was characterized by enhanced numbers of CD4+ cells, reduced numbers of activated cells as characterized by CD25 and CD69, and reduced numbers of memory (CD45RO+) cells relative to the GSHhigh population. Rather than directly affecting susceptibility to NO, these surface markers reflected different expression patterns. Particularly, the GSHlow subset was further characterized by decreased activity of the GSH synthesis related enzymes multi-drug resistance related protein (MRP)-1 and γ-glutamyltranspeptidase (γ-GT). Blocking γ-GT, using acivicin was shown to exacerbate NO-induced GSH depletion and NO-induced apoptosis. Since NO induced apoptosis selectively affects IFN-γ production these findings implicate GSH metabolism in the modulation and maintenance of the T helper (Th)1/Th2 balance. PMID:12423309

  1. Radiosensitivity of different aged human lymphocytes following electron irradiation in vitro

    International Nuclear Information System (INIS)

    Cytochalasin B-blocking micronucleus test and chromosomal aberration analysis were used in this study to estimate the yield of individual variability in radiation response of different aged human lymphocytes. Both analyses were performed in three groups of adults, aged 18-65 years, on two sampling times, following irradiation by therapeutical dose of 2 G in vitro. No statistically significant difference in the induced yield of exchange aberrations between individuals under consideration was found. The yield of total aberration data showed greater variability and was statistically significant in the oldest group against two other adult groups. Regarding to fixation times no statistically significant differences in the induced yield of chromosomal aberration (exchanges as well as total aberrations) were observed. The study has shown a slight increase in spontaneously occurring micronuclei with age. Almost equal mean number of radiation induced micronuclei was observed in the groups of adult aged 18-20 and 45-55 years. The highest mean number was observed in the oldest group. Evident variation in number of radiation induced micronuclei among individuals from the same age group was observed. The results of micronuclei assay for for all individuals under consideration show statistically significant difference in the yield of radiation-induced micronuclei regarding the second fixation time. This study has shown that cytochalasin-B blocking micronucleus test is more sensitive assay than chromosomal aberration analysis for the estimation of individual radiosensitivity. (author)

  2. Effect of tritiated compounds on sister-chromatid exchanges (SCE) in human lymphocytes in vitro

    International Nuclear Information System (INIS)

    Human lymphocytes treated in vitro with various activities of 3H-TdR and 3H-UdR were cultured to understand the effects of tritium on the cell cycle and the frequency of SCE. The results of these experiments indicated that both tritiated compounds make the frequency of SCE increase and the cell cycle delay. The frequency of SCE increased markedly with activity of 3H. With respect to delaying cell cycle, 3H-UdR was more effective than 3H-TdR. The average frequencies of SCE for 3H-UdR were higher than those for 3H-TdR. With the exception of 3.7 x 103 Bq/mL group and differences between other 3H-UdR groups and corresponding 3H-TdR group were significant (t test, p < 0.01). These results suggest that tritiated compounds may have the effect on the cell proliferating rate. The cell proliferating rate index (PRI) seems to be related with the frequency of SCE: the higher the frequency of SCE, the lower the PRI is

  3. Analysis of centromeres in radiation-induced micronuclei in human peripheral lymphocytes by means of Fish

    International Nuclear Information System (INIS)

    The micronucleus assay is frequently used in mutagenicity testing. Micronuclei can arise either from acentric fragments that fail to be incorporated into daughter nuclei or from whole chromosomes that lag in anaphase due to centromere dysfunction, defective spindle apparatus or complex chromosomal rearrangements. Several studies have shown that many micronuclei which arise spontaneously contain whole chromosomes. Relatively few data are available on the frequency of centromere positive micronuclei following exposure to ionizing radiation. In the present study we have analyzed the occurrence of centromere positive micronuclei in human peripheral lymphocytes of three donors following irradiation with X-rays. The centromeres were made visible with commercially available alpha-satellite probes labelled with biotin and detected with FITC-labelled avidin. Additionally, the micronucleus frequencies per bi-nucleated cells were estimated in Giemsa-stained slides. Our results show that the majority of control micronuclei contain whole chromosomes. With increasing dose the fraction of centromere positive micronuclei decreases indicating that the micronuclei contain predominantly acentric fragments. Individual differences in frequencies of centromere containing micronuclei were observed between the donors. There appears to be a negative correlation between the frequency of micronuclei and centromere within them. Further experiments with more donors are presently being carried out to substantiate this result. (authors)

  4. Stepwise maturation of lytic granules during differentiation and activation of human CD8+ T lymphocytes.

    Directory of Open Access Journals (Sweden)

    Yovan Sanchez-Ruiz

    Full Text Available During differentiation, cytotoxic T lymphocytes (CTL acquire their killing potential through the biogenesis and maturation of lytic granules that are secreted upon target cell recognition. How lytic granule load in lytic molecules evolves during CTL differentiation and which subsets of lytic granules are secreted following activation remains to be investigated. We set up a flow cytometry approach to analyze single lytic granules isolated from primary human CTL according to their size and molecular content. During CTL in vitro differentiation, a relatively homogeneous population of lytic granules appeared through the progressive loading of Granzyme B, Perforin and Granzyme A within LAMP1(+ lysosomes. PMA/ionomycin-induced lytic granule exocytosis was preceded by a rapid association of the docking molecule Rab27a to approximately half of the lytic granules. Activated CTL were found to limit exocytosis by sparing lytic granules including some associated to Rab27a. Our study provides a quantification of key steps of lytic granule biogenesis and highlights the potential of flow cytometry to study organelle composition and dynamics.

  5. Effects of anti-human T lymphocyte immune globulins in patients: new or old.

    Science.gov (United States)

    Wang, Diane C; Wang, Xiangdong; Chen, Chengshui

    2016-09-01

    Multiple studies demonstrated that anti-human T lymphocyte immune globulins (ATG) can decrease the incidence of acute and chronic graft rejection in cell or organ transplants. However, further in-depth study indicates that different subgroups may benefit from either different regimes or alteration of them. Studies among renal transplant patients indicate that low immunological risk patients may not gain the same amount of benefit and thus tilt the risk versus benefit consideration. This may hold true for low immunological risk patients receiving other organ transplants and would be worth further investigation. The recovery time of T cells and natural killer (NK) cells also bears consideration and the impact that it has on the severity and incidence of opportunistic infections closely correlated with the dosage of ATG. The use of lower doses of ATG in combination with other induction medications may offer a solution. The finding that ATG may lose efficacy in cases of multiple transplants or re-transplants in the case of heart transplants may hold true for other transplantations. This may lead to reconsideration of which induction therapies would be most beneficial in the clinical setting. These studies on ATG done on different patient groups will naturally not be applicable to all, but the evidence accrued from them as a whole may offer us new and different perspectives on how to approach and potentially solve the clinical question of how to best reduce the mortality associated with chronic host-versus-graft disease. PMID:27084794

  6. Unusually high frequencies of HIV-specific cytotoxic T lymphocytes in humans.

    Science.gov (United States)

    Hoffenbach, A; Langlade-Demoyen, P; Dadaglio, G; Vilmer, E; Michel, F; Mayaud, C; Autran, B; Plata, F

    1989-01-15

    CTL specific for the HIV belong to the CD8 subset of T lymphocytes, and their activity is restricted by class I HLA transplantation Ag. In this report, HIV-specific CTL and their precursor cells were quantified by limiting dilution analysis. CTL were recovered from the lungs, lymph nodes, and blood of asymptomatic seropositive carriers and of patients with AIDS. HIV was found to be very immunogenic. High frequencies of both HIV-specific CTL and CTL precursor cells were detected in infected individuals. These CTL killed autologous HIV-infected macrophages and T4 lymphoblasts. They also killed doubly transfected P815-A2-env-LAV mouse tumor cells, which express the human HLA-A2 gene and the HIV-1 env gene. In the longitudinal studies of two HIV-infected patients, CTL and CTL precursor cell frequencies decreased as the clinical and immunologic status of the patients deteriorated. Most surprisingly, PBL from seronegative donors also responded to HIV stimulation in vitro and generated large numbers of HLA-restricted, HIV-specific CTL.

  7. Induction of complete and incomplete chromosome aberrations by bleomycin in human lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Benkhaled, L.; Xuncla, M.; Caballin, M.R. [Universitat Autonoma de Barcelona, Unitat d' Antropologia Biologica, Departament de Biologia Animal, Biologia Vegetal i Ecologia, E-08193 Bellaterra (Spain); Barrios, L. [Universitat Autonoma de Barcelona, Unitat de Biologia Cel.lular, Departament de Biologia Cel.lular, Fisiologia i Immunologia (Spain); Barquinero, J.F. [Universitat Autonoma de Barcelona, Unitat d' Antropologia Biologica, Departament de Biologia Animal, Biologia Vegetal i Ecologia, E-08193 Bellaterra (Spain)], E-mail: Francesc.Barquinero@uab.es

    2008-01-01

    Bleomycin (BLM) is a clastogenic compound, which due to the overdispersion in the cell distribution of induced dicentrics has been compared to the effect of high-LET radiation. Recently, it has been described that in fibroblast derived cell lines BLM induces incomplete chromosome elements more efficiently than any type of ionizing radiation. The objective of the present study was to evaluate in human lymphocytes the induction of dicentrics and incomplete chromosome elements by BLM. Peripheral blood samples have been treated with different concentrations of BLM. Two cytogenetic techniques were applied, fluorescence plus Giemsa (FPG) and FISH using pan-centromeric and pan-telomeric probes. The observed frequency of dicentric equivalents increases linearly with the BLM concentration, and for all BLM concentrations the distribution of dicentric equivalents was overdispersed. In the FISH study the ratio between total incomplete elements and multicentrics was 0.27. The overdispersion in the dicentric cell distribution, and the linear BLM-concentration dependence of dicentrics can be compared to the effect of high-LET radiation, on the contrary the ratio of incomplete elements and multicentrics is similar to the one induced by low-LET radiation ({approx}0.40). The elevated proportion of interstitial deletions in relation to total acentric fragments, higher than any type of ionizing radiation could be a characteristic signature of the clastogenic effect of BLM.

  8. Study on the cytogenetic changes induced by benzene and hydroquinone in human lymphocytes.

    Science.gov (United States)

    Peng, D; Jiaxing, W; Chunhui, H; Weiyi, P; Xiaomin, W

    2012-04-01

    Benzene (BN) is a prototypical hematotoxicant, genotoxic carcinogen, and ubiquitous environmental pollutant. Although the molecular mechanisms of BN-induced cytotoxicity and genotoxic damage are poorly understood in humans, previous studies suggested that bioactivated BN metabolites are capable of oxidative stress, cell cycle arrest, apoptosis, and DNA damage. The objective of the current study was to investigate the BN-induced cytogenetic changes and underlying mechanisms based on these hypotheses. Peripheral blood lymphocytes (PBLs) might be the targets for BN-induced cytotoxicity and genotoxicity, and therefore DNA damage responses of PBLs after exposure to different concentrations of BN (0.25, 3.5, 50 μmol/L) or BN metabolite, hydroquinone (HQ; 50, 150, 450 μmol/L) were studied in vitro. Microculture tetrazolium assay, flow cytometry, 2',7'-dichlorodihydrofluorescein-diacetate assay, comet assay, micronuclei assay, and attenuated total reflectance microspectroscope were chosen for this study. Based on the results, we reached the conclusion that different concentrations of BN or HQ significantly inhibited cell growth, induced the arrest of S phase and G2/M phase, and increased late apoptosis in a concentration-dependent manner. Furthermore, evidence was also provided to support the conclusion that BN and HQ induced DNA strand breaks and chromosomal mutations in PBL, which indicated the genotoxicity of BN and HQ. Current evidence has indicated that multiple mechanisms including dysfunction of cell cycle, programmed cell death, oxidative stress, and DNA lesions are likely to contribute to BN-induced cytogenetic changes. PMID:22297702

  9. Dual adaptation and adaptive generalization of the human vestibulo-ocular reflex

    Science.gov (United States)

    Welch, R. B.; Bridgeman, B.; Williams, J. A.; Semmler, R.

    1998-01-01

    In two experiments, we examined the possibility that the human vestibulo-ocular reflex (VOR) is subject to dual adaptation (the ability to adapt to a sensory rearrangement more rapidly and/or more completely after repeated experience with it) and adaptive generalization (the ability to adapt more readily to a novel sensory rearrangement as a result of prior dual adaptation training). In Experiment 1, the subjects actively turned the head during alternating exposure to a visual-vestibular rearrangement (target/head gain = 0.5) and the normal situation (target/head gain = 0.0). These conditions produced both adaptation and dual adaptation of the VOR but no evidence of adaptive generalization when tested with a target/head gain of 1.0. Experiment 2, in which exposure to the 0.5 gain entailed externally controlled (i.e., passive) whole body rotation, resulted in VOR adaptation but no dual adaptation. As in Experiment 1, no evidence of adaptive generalization was found.

  10. Charybdotoxin inhibits proliferation and interleukin 2 production in human peripheral blood lymphocytes.

    OpenAIRE

    Price, M; Lee, S. C.; Deutsch, C.

    1989-01-01

    We demonstrate that blockade of the lymphocyte voltage-gated K+ channel by charybdotoxin (CTX) inhibits lymphocyte mitogenesis. Charybdotoxin blocks conductance with a Ki of 0.3 nM and inhibits mitogen- and antigen-stimulated proliferation with a Ki of 0.5 nM. As opposed to the other blockers of the lymphocyte K+ channel, the inhibition of mitogenesis by CTX can be overcome selectively by exogenous recombinant interleukin 2 (IL-2); endogenous levels of IL-2 in the culture supernatants of stim...

  11. CR2-mediated activation of the complement alternative pathway results in formation of membrane attack complexes on human B lymphocytes

    DEFF Research Database (Denmark)

    Nielsen, C H; Marquart, H V; Prodinger, W M;

    2001-01-01

    Normal human B lymphocytes activate the alternative pathway of complement via complement receptor type 2 (CR2, CD21), that binds hydrolysed C3 (iC3) and thereby promotes the formation of a membrane-bound C3 convertase. We have investigated whether this might lead to the generation of a C5...... convertase and consequent formation of membrane attack complexes (MAC). Deposition of C3 fragments and MAC was assessed on human peripheral B lymphocytes in the presence of 30% autologous serum containing 4.4 mM MgCl2/20 mM EGTA, which abrogates the classical pathway of complement without affecting...... the alternative pathway. Blockade of the CR2 ligand-binding site with the monoclonal antibody FE8 resulted in 56 +/- 13% and 71 +/- 9% inhibition of the C3-fragment and MAC deposition, respectively, whereas the monoclonal antibody HB135, directed against an irrelevant CR2 epitope, had no effect. Blockade...

  12. Methods for defining distinct bioenergetic profiles in platelets, lymphocytes, monocytes, and neutrophils, and the oxidative burst from human blood

    OpenAIRE

    Chacko, Balu K; Kramer, Philip A.; Ravi, Saranya; Johnson, Michelle S.; Hardy, Robert W.; Ballinger, Scott W.; Darley-Usmar, Victor M.

    2013-01-01

    Peripheral blood mononuclear cells and platelets have long been recognized as having the potential to act as sensitive markers for mitochondrial dysfunction in a broad range of pathological conditions. However, the bioenergetic function of these cells has not been examined from the same donors, yet this is important for the selection of cell types for translational studies. Here, we demonstrate the measurement of cellular bioenergetics in isolated human monocytes, lymphocytes, and platelets, ...

  13. Reversal of DNA methylation with 5-azacytidine alters chromosome replication patterns in human lymphocyte and fibroblast cultures.

    OpenAIRE

    Shafer, D A; Priest, J H

    1984-01-01

    Prior studies demonstrated that developmental or induced methylation of DNA can inactivate associated gene loci. Such DNA methylation can be reversed and specific genes reactivated by treatment with 5-azacytidine (5- azaC ). The present cytogenetic studies using replication banding methods show that 5- azaC treatment also results in an increase or decrease in replication staining at one or more band locations in human lymphocyte and fibroblast chromosomes. New replication band locations are n...

  14. Evaluation of Genotoxic and Cytotoxic Effects in Human Peripheral Blood Lymphocytes Exposed In Vitro to Neonicotinoid Insecticides News

    OpenAIRE

    María Elena Calderón-Segura; Sandra Gómez-Arroyo; Rafael Villalobos-Pietrini; Carmen Martínez-Valenzuela; Yolanda Carbajal-López; María del Carmen Calderón-Ezquerro; Josefina Cortés-Eslava; Rocío García-Martínez; Diana Flores-Ramírez; María Isabel Rodríguez-Romero; Patricia Méndez-Pérez; Enrique Bañuelos-Ruíz

    2012-01-01

    Calypso (thiacloprid), Poncho (clothianidin), Gaucho (imidacloprid), and Jade (imidacloprid) are commercial neonicotinoid insecticides, a new class of agrochemicals in México. However, genotoxic and cytotoxic studies have not been performed. In the present study, human peripheral blood lymphocytes (PBL) were exposed in vitro to different concentrations of the four insecticides. The genotoxic and cytotoxic effects were evaluated using the alkaline comet and trypan blue dye exclusion assays. DN...

  15. Polymerase chain reaction detection of adenovirus DNA sequences in human lymphocytes

    Directory of Open Access Journals (Sweden)

    Araújo Aufra A.

    2001-01-01

    Full Text Available Human lymphoid cells frequently carry adenoviruses and DNA sequences have been identified in peripheral blood lymphocytes by Southern blot and PCR, although these cells are not permissive for virus replication, suggesting persistence of the viral genome. In order to investigate this phenomenon we screened non-symptomatic volunteers for adenovirus DNA presence and E1A gene expression. DNA samples extracted from peripheral blood mononuclear cells of 51 volunteers were submitted to PCR using primers for a conserved hexon sequence, followed by nested PCR. Adenovirus sequences were detected in 27 samples (52.9%. After more than one year, new samples of these positive volunteers were analyzed and in 70.8% of the cases the result was maintained. Since this could be due to a possible persistence we checked if the early gene E1A was involved analyzing its expression by RT-PCR. For that purpose we developed a pair of primers to target a conserved region in the E1A gene. The RT-PCR results for E1A were negative for all samples. Using these primers it was possible to detect adenovirus sequences directly by PCR in DNA samples and we found 84% agreement in comparison to the hexon analysis. Our data suggest a high occurrence and persistence of adenovirus genome sequences in human lymphoid cells, and an indication that a region other than E1A is involved in persistence. We also can say that E1A gene is a good choice for amplification as a tool in adenovirus detection, avoiding the high risk of contamination in the nested PCR procedure necessary for hexon detection.

  16. Inhibitory Effects of Berberine on the Activation and Cell Cycle Progression of Human Peripheral Lymphocytes

    Institute of Scientific and Technical Information of China (English)

    Lihui Xu; Yi Liu; Xianhui He

    2005-01-01

    The immunosuppressive property of berberine, an isoquinoline alkaloid, has been well documented, but the mechanism of its action on lymphocytes has not been completely elucidated. The present study is to investigate the effect of berberine on the activation and proliferation of lymphocytes, in particular T lymphocytes. Whole peripheral blood from healthy donors was stimulated with phytohemagglutinin (PHA) alone or phorbol dibutyrate (PDB) plus ionomycin, and the expression of CD69 and CD25 on T lymphocytes was evaluated with flow cytometry.The distribution of cell cycles and cell viability were analyzed by staining with propidium iodide (PI) and 7-aminoactinomycin D (7-AAD), respectively. The results showed that 100 μmol/L and 50 μmol/L of berberine significantly inhibited CD69 expression on T cells stimulated with PDB plus ionomycin or PHA, whereas the effect of 25 μmol/L berberine was not significant. As the incubation time increased, the extent of inhibition decreased.Similarly, the expression of CD25 was also reduced by berberine in a dose-dependent manner over the concentration range of 25-100 μmol/L. Besides, this alkaloid could block lymphocyte cell cycle progression from G0/G1 phase to S and G2/M phase without phase specificity. Moreover, analysis following 7-AAD staining revealed that berberine had no significant cytotoxicity on lymphocytes. Taken together, berberine significantly inhibits the expression of activation antigens on T lymphocytes and also blocks the progression of cell cycles of lymphocytes,suggesting that berberine may exert immunosuppressive effect through inhibiting the activation and proliferation of T cells.

  17. Human circulating plasma DNA significantly decreases while lymphocyte DNA damage increases under chronic occupational exposure to low-dose gamma-neutron and tritium β-radiation

    International Nuclear Information System (INIS)

    Highlights: • The chronic exposure to low-dose IR induces DSBs in human lymphocytes (TM index). • Exposure to IR decreases the level of human circulating DNA (cfDNA index). • IR induces an increase of DNase1 activity (DNase1 index) in plasma. • IR induces an increase of the level of antibodies to DNA (Ab DNA index) in plasma. • The ratio cfDNA/(DNase 1 × Ab DNA × TM) is a potential marker of human exposure to IR. - Abstract: The blood plasma of healthy people contains cell-fee (circulating) DNA (cfDNA). Apoptotic cells are the main source of the cfDNA. The cfDNA concentration increases in case of the organism’s cell death rate increase, for example in case of exposure to high-dose ionizing radiation (IR). The objects of the present research are the blood plasma and blood lymphocytes of people, who contacted occupationally with the sources of external gamma/neutron radiation or internal β-radiation of tritium N = 176). As the controls (references), blood samples of people, who had never been occupationally subjected to the IR sources, were used (N = 109). With respect to the plasma samples of each donor there were defined: the cfDNA concentration (the cfDNA index), DNase1 activity (the DNase1 index) and titre of antibodies to DNA (the Ab DNA index). The general DNA damage in the cells was defined (using the Comet assay, the tail moment (TM) index). A chronic effect of the low-dose ionizing radiation on a human being is accompanied by the enhancement of the DNA damage in lymphocytes along with a considerable cfDNA content reduction, while the DNase1 content and concentration of antibodies to DNA (Ab DNA) increase. All the aforementioned changes were also observed in people, who had not worked with the IR sources for more than a year. The ratio cfDNA/(DNase1 × Ab DNA × TM) is proposed to be used as a marker of the chronic exposure of a person to the external low-dose IR. It was formulated the assumption that the joint analysis of the cfDNA, DNase1, Ab

  18. Human circulating plasma DNA significantly decreases while lymphocyte DNA damage increases under chronic occupational exposure to low-dose gamma-neutron and tritium β-radiation

    Energy Technology Data Exchange (ETDEWEB)

    Korzeneva, Inna B., E-mail: inna.korzeneva@molgen.vniief.ru [Russian Federal Nuclear Center – All-Russian Research Institute of Experimental Physics (RFNC-VNIIEF) 607190, Sarov, 37 Mira ave., Nizhniy Novgorod Region (Russian Federation); Kostuyk, Svetlana V.; Ershova, Liza S. [Research Centre for Medical Genetics, Russian Academy of Medical Sciences, 115478 Moscow, 1 Moskvorechye str. (Russian Federation); Osipov, Andrian N. [Federal Medial and Biological Center named after Burnazyan of the Federal Medical and Biological Agency (FMBTz named after Burnazyan of FMBA), Moscow (Russian Federation); State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Zhivopisnaya, 46, Moscow, 123098 (Russian Federation); Zhuravleva, Veronika F.; Pankratova, Galina V. [Russian Federal Nuclear Center – All-Russian Research Institute of Experimental Physics (RFNC-VNIIEF) 607190, Sarov, 37 Mira ave., Nizhniy Novgorod Region (Russian Federation); Porokhovnik, Lev N.; Veiko, Natalia N. [Research Centre for Medical Genetics, Russian Academy of Medical Sciences, 115478 Moscow, 1 Moskvorechye str. (Russian Federation)

    2015-09-15

    Highlights: • The chronic exposure to low-dose IR induces DSBs in human lymphocytes (TM index). • Exposure to IR decreases the level of human circulating DNA (cfDNA index). • IR induces an increase of DNase1 activity (DNase1 index) in plasma. • IR induces an increase of the level of antibodies to DNA (Ab DNA index) in plasma. • The ratio cfDNA/(DNase 1 × Ab DNA × TM) is a potential marker of human exposure to IR. - Abstract: The blood plasma of healthy people contains cell-fee (circulating) DNA (cfDNA). Apoptotic cells are the main source of the cfDNA. The cfDNA concentration increases in case of the organism’s cell death rate increase, for example in case of exposure to high-dose ionizing radiation (IR). The objects of the present research are the blood plasma and blood lymphocytes of people, who contacted occupationally with the sources of external gamma/neutron radiation or internal β-radiation of tritium N = 176). As the controls (references), blood samples of people, who had never been occupationally subjected to the IR sources, were used (N = 109). With respect to the plasma samples of each donor there were defined: the cfDNA concentration (the cfDNA index), DNase1 activity (the DNase1 index) and titre of antibodies to DNA (the Ab DNA index). The general DNA damage in the cells was defined (using the Comet assay, the tail moment (TM) index). A chronic effect of the low-dose ionizing radiation on a human being is accompanied by the enhancement of the DNA damage in lymphocytes along with a considerable cfDNA content reduction, while the DNase1 content and concentration of antibodies to DNA (Ab DNA) increase. All the aforementioned changes were also observed in people, who had not worked with the IR sources for more than a year. The ratio cfDNA/(DNase1 × Ab DNA × TM) is proposed to be used as a marker of the chronic exposure of a person to the external low-dose IR. It was formulated the assumption that the joint analysis of the cfDNA, DNase1, Ab

  19. Phenytoin influence on human lymphocyte mitogen response: a prospective study of epileptic and nonepileptic patients.

    Science.gov (United States)

    Gabourel, J D; Davies, G H; Bardana, E J; Ratzlaff, N A

    1982-08-01

    The results of this prospective study fail to confirm previously reported phenytoin suppression of lymphocyte responsiveness to mitogens. Our data show a significantly greater than expected percentage (p less than 0.0001) of patients requiring phenytoin treatment have low lymphocyte responsiveness to mitogens prior to phenytoin therapy. Analysis of changes in each individual's response during phenytoin treatment as compared with their pre-phenytoin responses shows a consistent trend to increased responsiveness to concanavalin A, pokeweed mitogen, and to a suboptimal concentration of phytohemagglutinin. This trend was most pronounced for patients whose serum IgA concentration was decreased while taking phenytoin, whereas there was no such trend for individuals whose serum IgA levels were not decreased. This phenomenon was not related to neurological disease classification. Phenytoin added directly to lymphocyte cultures depressed lymphocyte responses to all mitogens in a small (less than 20%) but significant degree, confirming similar in vitro studies by other investigators. Because of limited serum proteins for phenytoin binding in culture medium, these in vitro studies have little application to possible phenytoin effects on lymphocytes of patients taking it to prevent seizures. Thus, the suggestion that phenytoin causes depressed lymphocyte responses to mitogens in epileptic patients appears unwarranted. PMID:7094904

  20. Variation of the symmetrical/asymmetrical ratio in chromatid interchanges during the various phases of the cell cycle of human lymphocytes 'in vitro'

    International Nuclear Information System (INIS)

    Experiments have been performed to verify whether in a human euploid cell system, such as lymphocyte cultures in vitro, there is a differential pattern of induction of chromatid exchanges in the various phases of the cycle. (Auth.)

  1. Cognitive adaptations for gathering-related navigation in humans

    Science.gov (United States)

    Krasnow, Max M.; Truxaw, Danielle; Gaulin, Steven J.C.; New, Joshua; Ozono, Hiroki; Uono, Shota; Ueno, Taiji; Minemoto, Kazusa

    2013-01-01

    Current research increasingly suggests that spatial cognition in humans is accomplished by many specialized mechanisms, each designed to solve a particular adaptive problem. A major adaptive problem for our hominin ancestors, particularly females, was the need to efficiently gather immobile foods which could vary greatly in quality, quantity, spatial location and temporal availability. We propose a cognitive model of a navigational gathering adaptation in humans and test its predictions in samples from the US and Japan. Our results are uniformly supportive: the human mind appears equipped with a navigational gathering adaptation that encodes the location of gatherable foods into spatial memory. This mechanism appears to be chronically active in women and activated under explicit motivation in men. PMID:23833551

  2. Radiation-induced changes in expression of genes related to DNA damage response in lymphocytes of human peripheral blood

    International Nuclear Information System (INIS)

    Objective: To detect the expression of DNA damage response genes induced by radiation in human peripheral blood lymphocyte, and to explore the new biomarkers of radiation. Methods: The human peripheral blood cells were irradiated to X-rays at different doses of 0, 1, 2, 3, 4, and 5 Gy. The quantitative real, time qPCR wag used to detect the expressions of cyclin-dependent kinase inhibitor l a gene (Cdkn1 a) and growth arrest and DNA damage inducible gene (Gadd45α) in lymphocytes at 4 and 24 h post-irradiation, respectively.The method of CB micronucleus was used to determine the change of micronucleus ratio. Results: The expression of Cdkn1 a in peripheral blood lymphocytes wag increased significantly at 4 and 24 h post-irradiation to 0-5 Gy, reached the peak at 4 Gy and began to decrease at 5 Gy, which showed a dose-dependent manner (r=0.946, 0.975, P<0.05). Similarly, the expression of Gadd45α in human peripheral blood lymphocytes was also increased significantly at 4 and 24 h post-irradiation to 0-5 Gy in a dose-dependent manner,while the expression of Gadd45α at 4 h wag higher than that at 24 h (r=0.936, 0.797, P<0.05). The ratio of micronuclei wag increased significantly at 4 and 24 h post-irradiation to 0-5 Gy (r=0.990, 0.984, P<0.05). Conclusions: Cdkn1 a and Gadd45α expression could be increased significantly at 4 and 24 h post-irradiation to 0-5 Gy, showing a good linear relationship, which might be candidate for radiation biological dosimeter. (authors)

  3. Investigation into the Role of Phosphatidylserine in Modifying the Susceptibility of Human Lymphocytes to Secretory Phospholipase A2 using Cells Deficient in the Expression of Scramblase

    OpenAIRE

    Nelson, Jennifer; Francom, Lyndee L.; Anderson, Lynn; Damm, Kelly; Baker, Ryan; Chen, Joseph; Franklin, Sarah; Hamaker, Amy; Izidoro, Izadora; Moss, Eric; Orton, Mikayla; Stevens, Evan; Yeung, Celestine; Allan M. Judd; Bell, John D.

    2012-01-01

    Normal human lymphocytes resisted the hydrolytic action of secretory phospholipase A2 but became susceptible to the enzyme following treatment with a calcium ionophore, ionomycin. To test the hypothesis that this susceptibility requires exposure of the anionic lipid phosphatidylserine on the external face of the cell membrane, experiments were repeated with a human Burkitt’s lymphoma cell line (Raji cells). In contrast to normal lymphocytes or S49 mouse lymphoma cells, most of the Raji cells ...

  4. Platelet-Activating Factor Antagonists Decrease Follicular Dendritic-Cell Stimulation of Human B Lymphocytes

    Directory of Open Access Journals (Sweden)

    Halickman Isaac

    2005-06-01

    Full Text Available Abstract Both B-lymphoblastoid cell lines and tonsillar B lymphocytes express receptors for platelet-activating factor (PAF. In lymph node germinal centres, B lymphocytes interact with follicular dendritic cells (FDCs, which present antigen-containing immune complexes to B lymphocytes. FDCs have phenotypic features that are similar to those of stromal cells and monocytes and may therefore be a source of lipid mediators. In this study, we evaluated the effects of the PAF antagonist WEB 2170 on the activation of tonsillar B lymphocytes by FDCs. FDCs were isolated from tonsils by Bovine Serum Albumin (BSA gradient centrifugation. After being cultured for 6 to 10 days, they were incubated with freshly isolated B cells in the presence or absence of the specific PAF receptor antagonist WEB 2170. B-lymphocyte proliferation was assessed by [3H]-thymidine incorporation, and immunoglobulin (Ig G and IgM secretion was assessed by enzyme-linked immunosorbent assay (ELISA. WEB 2170 (10-6 to 10-8 M inhibited [3H]-thymidine incorporation by up to 35% ± 3%. Moreover, the secretion of IgG and IgM was inhibited by up to 50% by WEB 2170 concentrations ranging from 10-6 to 10-8 M. There was no evidence of toxicity by trypan blue staining, and the addition of WEB 2170 to B cells in the absence of FDCs did not inhibit the spontaneous production of IgG or IgM. The effect of the PAF antagonist is primarily on B lymphocytes, as reverse transcription polymerase chain reaction detected little PAF receptor messenger ribonucleic acid (mRNA from FDCs. These data suggest that endogenous production of PAF may be important in the interaction of B lymphocytes with FDCs.

  5. Quantitative study on La3+ influx mediated by sodium-calcium exchanger in human lymphocytes

    Institute of Scientific and Technical Information of China (English)

    魏春英; 杨频

    2002-01-01

    Whether La3+ can enter human peripheral blood lymphocytes by the Na+/Ca2+ exchanger or not and the effect of La3+ on the Na+/Ca2+ exchanger activity are examined by fura-2 technique. And that whether La3+ is sequestered by intracellular organelles (mainly endoplasmic reticulum and mitochondria) is studied by this method. La3+ uptake is obviously stimulated by pretreating the cells with ouabain and by removing extracellular Na+, and intracellular La3+ concentration ([La3+]i) is directly proportional to its extracellular concentration ([La3+]o). But when [La3+]o exceeds 0.4 mmol/L, the 340/380 nm ratio of fluorescence is no longer varied and the maximum [La3+]i is 1.5×10-12 mol@L-1. The higher concentration of La3+ (0.1 mmol/L) increases Na+/Ca2+ exchange-mediated calcium influx, but lower concentration (10 mmol/L) appears to block calcium influx. The results also suggest that cytosolic La3+ is transported by the ATP-dependent Ca2+ pump. Intracellular Ca2+ stores are depleted by ionomycin, and then ionomycin is added again during the period of La3+ uptake, the 340/380 nm ratio of fluorescence is also increased, these results indicate that La3+ is sequestered by intracellular organelles. A characterization of fura-2-La3+ interaction in solution simulating intracellular ionic composition (pH 7.05) shows that La3+ forms a 1:1 fura-2-La3+complex, and the apparent dissociation constant of La3+ for fura-2 (Kd) is 1.7×10-12 mol@L-1. In addition, the limit of detection of fura-2 for La3+ and Ca2+ is 10?12 and 10?8 mol@L-1 respectively.

  6. SPECIFIC UPTAKE OF MONOCLONAL ANTIBODY-CONJUGATED METHOTREXATE BY HUMAN LYMPHOCYTIC LEUKEMIC B CELLS

    Institute of Scientific and Technical Information of China (English)

    Zhu Zhenping; Yang Chunzheng; Tarunendu Ghose; Jaroslav Kralovec

    1998-01-01

    Objective: To analysis the uptake of free MTX and MTX conjugated to tumor specific monoclonal antibody by target and non-target cells. Methods: The folate antagonist methotrexate (MTX) was conjugated to two monoclonal antibodies (Mab) directed against human chronic lymphocytic leukemia (CLL), Dal B01 and Dal B02, by an active ester method. Both conjugates were more cytotoxic toward the target tumor cell line D10-1than to the non-target cell line MOLT-3, and Dal B02-MTX conjugate was more inhibitory to D10-1 cells than free MTX in a 6 h pulse exposure assay. Results: Drug uptake studies revealed that D10-1 cells took up much more Dal B01 and Dal B02-conjugated MTX than free MTX. The amounts of drug taken up by D10-1 cells incubated with Dal B01 and Dal B02-conjugated MTX were always 3 to 5-fold higher than that taken up by MOLT-3 cells, although the latter took up more drug when incubated with free MTX. Furthermore, tumor cells incubated with Dal B01 or Dal B02-conjugated MTX retained much larger amounts of drug for a prolonged period of time than those incubated with free MTX.Conclusion: The enhanced specific cytotoxicity of Dal B01 and Dal B02-MTX conjugates toward target tumor cells is therefore likely due to (Ⅰ) delivery of larger amounts of MTX to target cells when the drug is conjugated to Mab;(ii) longer retention of Mab-conjugated MTX by target cells; and (iii) slow, prolonged release of MTX from the surface-bound or endocytosed conjugates, rendering them into a sustained release dosage form.

  7. Cytosine arabinoside enhancement of gamma irradiation induced mutations in human T-lymphocytes

    International Nuclear Information System (INIS)

    The frequency of 6-thioguanine resistant (TGr) mutants induced in human G0 phase T-lymphocytes by 200 cGy of gamma irradiation is greatly enhanced by incubation with cytosine arabinoside (ara-C) after irradiation. The mutant frequency increased with increasing incubation time in ara-C for up to 2 hr. This mutation induction required a phenotypic expression time of 5-8 days mass culture growth, similar to that found with mutants induced by 300 cGy of irradiation alone. Southern blot analysis of 40 isolated mutant clones revealed 8 independent mutations by T-cell receptor (TCR) gene rearrangement patterns. Four of these eight showed hprt gene structural alterations (0.50). An alternative method to allow phenotypic expression was developed to minimize the isolation of hprt/TCR sibling mutants. The use of in situ expression in the microtiter dish wells resulted in the isolation of 17 independent mutations in 19 mutant clones. Ten of these 17 mutations showed hprt structural alterations (0.59). The high fraction of mutations involving structural alterations detected by Southern blot analysis is consistent with the known induction of chromosome aberrations by irradiation plus ara-C treatment. We propose that both the increase in Mf and the increase in the incidence of hprt gene structural alterations are due to the accumulation of strand breaks in repairing regions of DNA under these conditions of ara-C induced inhibition of repair. We further propose that upon release of the ara-C inhibition, these repairing regions can interact to yield both gene mutations and chromosome aberrations

  8. Studying the genotoxicity of vincristine on human lymphocytes using comet assay, micronucleus assay and TCR gene mutation test in vitro

    International Nuclear Information System (INIS)

    The results of our previous investigation for workers occupationally exposed to vincristine (VCR) indicated that the genetic damage was detectable with comet assay, cytokinesis-block micronucleus (CBMN) assay and housekeeping gene mutation tests. In order to determine the results of above investigation and to inquire further the characteristics of genotoxicity of VCR, the cytogenetic effects of VCR on human lymphocytes were assessed with comet assay, CBMN assay and T-cell receptor (TCR) gene mutation test in vitro. The lymphocytes from two healthy donors were incubated for 24 h at doses of 0.00, 0.01, 0.02, 0.04, and 0.08 μg ml-1 VCR. The results of the present experiment showed that VCR not only could induce DNA damage, increase significantly micronucleus frequencies and the apoptotic cell ratios and decrease the nuclear division index (NDI) with dose-response relationship, but also could produce nucleoplasmic bridges (NPBs), a biomarker of DNA misrepair and/or telomere end-fusions and nuclear buds (NBUDs), a biomarker of elimination of amplified DNA and/or DNA repair complexes. Moreover, VCR could enhance TCR gene mutation frequency (Mf-TCR) of human lymphocytes. There was good correlation between the parameters (mean tail length, mean tail moment, micronucleus frequency, micronucleated frequency and Mf-TCR). The results of present study supported the results of our previous investigation for workers occupationally exposed to VCR, and the genotoxicity of VCR was determined at the different genetic end-points in vitro

  9. Syzygium cumini (Jamun) reduces the radiation-induced DNA damage in the cultured human peripheral blood lymphocytes: a preliminary study.

    Science.gov (United States)

    Jagetia, Ganesh Chandra; Baliga, Manjeshwar Shrinath

    2002-06-01

    The effects of various concentrations (0.0, 1.56, 3.125, 6.25, 12.5, 25, 50 and 100 microg/ml) of the leaf extract of Syzygium cumini Linn. or Eugenia cumini (SC; black plum, Jamun, family Myrtaceae) was studied on the alteration in the radiation-induced micronuclei formation in the cultured human peripheral blood lymphocytes. Treatment of lymphocytes to various concentrations of SC resulted in a dose dependent increase in the micronuclei-induction, especially after 25-100 microg/ml extract. The exposure of human lymphocytes to various concentrations of SC extract before 3 Gy gamma-irradiation resulted in a significant decline in the micronuclei-induction at all the drug doses when compared with the non-drug treated irradiated cultures. A nadir in MNBNC frequency was observed for 12.5 microg/ml drug concentration, where the MNBNC frequency was approximately fourfold lower than that of the non-drug treated irradiated cultures. Therefore, this dose may be considered as an optimum dose for radiation protection. Our study demonstrates that the leaf extract of S. cumini, a plant traditionally used to treat diabetic disorders protects against the radiation-induced DNA damage. PMID:12084616

  10. gp140, the C3d receptor of human B lymphocytes, is also the Epstein-Barr virus receptor.

    Science.gov (United States)

    Frade, R; Barel, M; Ehlin-Henriksson, B; Klein, G

    1985-03-01

    The relationship between gp140, the membrane C3d receptor (CR2) of human B lymphocytes, and the Epstein-Barr virus receptor (EBVR) was analyzed by using the polyclonal anti-gp140, previously prepared by immunizing rabbits with highly purified gp140 (isolated by some of us) from CR2/EBVR-positive Raji cells. Polyclonal anti-gp72, a C3-binding membrane component, not related to the EBVR but also expressed on the Raji cell surface, was used as a control. Binding of rabbit IgG and EBV on cells was assessed by using immunofluorescence techniques with analysis by flow cytofluorometry. A semiquantitative bioassay was also used to measure the EBV binding. Polyclonal monospecific anti-gp140 IgG inhibits directly the binding of EBV to Raji cells at the same concentration that inhibits the binding of EC3d on cells, whereas a 35 times higher concentration of anti-gp72 IgG or preimmune serum IgG does not. Anti-gp140 IgG treatment also inhibits the induction of EBV-determined nuclear antigen in normal tonsil B lymphocytes or in EBV-negative Ramos cells, whereas high concentrations of anti-gp72 IgG or preimmune serum IgG have no effect. These data strongly suggest that gp140, the CR2 of human B lymphocytes, is also the EBVR. PMID:2983347

  11. Learning, menopause, and the human adaptive complex.

    Science.gov (United States)

    Kaplan, Hillard; Gurven, Michael; Winking, Jeffrey; Hooper, Paul L; Stieglitz, Jonathan

    2010-08-01

    This paper presents a new two-sex learning- and skills-based theory for the evolution of human menopause. The theory proposes that the role of knowledge, skill acquisition, and transfers in determining economic productivity and resource distribution is the distinctive feature of the traditional human ecology that is responsible for the evolution of menopause. The theory also proposes that male reproductive cessation and post-reproductive investment in descendants is a fundamental characteristic of humans living in traditional foraging and simple horticultural economies. We present evidence relevant to the theory. The data show that whereas reproductive decline is linked to increasing risks of mortality in chimpanzees, human reproductive senescence precedes somatic senescence. Moreover under traditional conditions, most human males undergo reproductive cessation at the same time as their wives. We then present evidence that after ceasing to reproduce, both men and women provide net economic transfers to children and grandchildren. Given this pattern of economic productivity, delays in menopause would produce net economic deficits within families. PMID:20738273

  12. Analysis of purine metabolic enzymes in human CD4 Leu 8- and CD4 Leu 8+ lymphocyte subpopulations.

    Science.gov (United States)

    Fernandez-Mejia, C; Polmar, S H; Peralta-Zaragoza, O; Madrid-Marina, V

    1993-02-01

    1. Specific activities of adenosine deaminase, purine nucleoside phosphorylase, adenosine kinase, 5'-nucleotidase, S-adenosyl-L-homocysteine hydrolase, AMP deaminase, adenine phosphoribosyl transferase, and hypoxanthine phosphoribosyl transferase were analyzed in human CD4 T-lymphocyte subsets. 2. CD4 Leu 8- (helper/inducer) and CD4 Leu 8+ (suppressor/inducer) subpopulations were obtained by panning or fluorescence activated cell sorting techniques using specific monoclonal antibodies. 3. A 45% decrease of 5'-NT AMP activity in the CD4 Leu 8- cells (suppressor/inducer) compared with CD4 total cell population. 4. No statistical significant differences in enzyme activity were found between the subsets analyzed in other purine enzymes. 5. These results suggest that the distribution of purine metabolic enzymes is homogeneous in CD4 Leu 8- and CD4 Leu 8+ T-lymphocyte subpopulations. PMID:8444317

  13. Influence of nitroimidazole derivatives and irradiation on the DNA synthesis of L5178Y cells and human lymphocytes

    International Nuclear Information System (INIS)

    The radiosensitizing effect of 4-nitroimidazoles a further substance similar to the known 2-nitroderivative misonidazole was involved in the testing. The investigation with four different nitroimidazole derivatives carried out under the same conditions permit a good comparison of their effectiveness for the selected criteria. The influence of these substances on the DNA synthesis before and after irradiation was examined in vitro in L5178Y cells and human lymphocytes. Regarding their inhibitory effect on DNA synthesis, all substances in a radiotherapeutically relevant concentration are without effect for well oxygenated cells. This also applies to hypoxic cultures, except the 2-nitroimidazole. The radiation-induced inhibition of the DNA synthesis is considerably intensified by all derivatives only under hypoxia. The radiation-induced DNA synthesis in lymphocytes is not influenced. (author)

  14. Inhibition of human lymphocyte proliferation and cleavage of interleukin-2 by Pseudomonas aeruginosa proteases

    DEFF Research Database (Denmark)

    Theander, T G; Kharazmi, A; Pedersen, B K;

    1988-01-01

    This study was undertaken to determine the effect of Pseudomonas aeruginosa alkaline protease (AP) and elastase (ELA) on human lymphocyte function. AP at 50 micrograms/ml and ELA at 12 micrograms/ml caused a 50% inhibition of phytohemagglutinin-induced proliferation. There was no difference...... in the effect of proteases on CD4- and CD8-positive cells. To determine the effect of proteases on interleukin-2 (IL-2)-induced cell proliferation, the proteases and IL-2 were added to the IL-2-dependent CTLL-2 cell line. AP and ELA inhibited the proliferation of these cells. When IL-2 was added in excess......, the inhibition was partly reversed. ELA at 10 micrograms/ml cleaved IL-2, as judged by size chromatography of a reaction mixture containing 125I-labeled IL-2 and the proteases. The ELA-digested IL-2 exhibited a reduced binding capacity to IL-2 receptors on the lymphocytes. Furthermore, treatment...

  15. From lifetime to evolution: timescales of human gut microbiota adaptation

    Directory of Open Access Journals (Sweden)

    Sara eQuercia

    2014-11-01

    Full Text Available Human beings harbor gut microbial communities that are essential to preserve human health. Molded by the human genome, the gut microbiota is an adaptive component of the human superorganisms that allows host adaptation at different timescales, optimizing host physiology from daily life to lifespan scales and human evolutionary history. The gut microbiota continuously changes from birth up to the most extreme limits of human life, reconfiguring its metagenomic layout in response to daily variations in diet or specific host physiological and immunological needs at different ages. On the other hand, the microbiota plasticity was strategic to face changes in lifestyle and dietary habits along the course of the recent evolutionary history, that has driven the passage from Paleolithic hunter-gathering societies to Neolithic agricultural farmers to modern Westernized societies.

  16. From lifetime to evolution: timescales of human gut microbiota adaptation.

    Science.gov (United States)

    Quercia, Sara; Candela, Marco; Giuliani, Cristina; Turroni, Silvia; Luiselli, Donata; Rampelli, Simone; Brigidi, Patrizia; Franceschi, Claudio; Bacalini, Maria Giulia; Garagnani, Paolo; Pirazzini, Chiara

    2014-01-01

    Human beings harbor gut microbial communities that are essential to preserve human health. Molded by the human genome, the gut microbiota (GM) is an adaptive component of the human superorganisms that allows host adaptation at different timescales, optimizing host physiology from daily life to lifespan scales and human evolutionary history. The GM continuously changes from birth up to the most extreme limits of human life, reconfiguring its metagenomic layout in response to daily variations in diet or specific host physiological and immunological needs at different ages. On the other hand, the microbiota plasticity was strategic to face changes in lifestyle and dietary habits along the course of the recent evolutionary history, that has driven the passage from Paleolithic hunter-gathering societies to Neolithic agricultural farmers to modern Westernized societies. PMID:25408692

  17. Diminution of Oxidative Damage to Human Erythrocytes and Lymphocytes by Creatine: Possible Role of Creatine in Blood.

    Directory of Open Access Journals (Sweden)

    Neha Qasim

    Full Text Available Creatine (Cr is naturally produced in the body and stored in muscles where it is involved in energy generation. It is widely used, especially by athletes, as a staple supplement for improving physical performance. Recent reports have shown that Cr displays antioxidant activity which could explain its beneficial cellular effects. We have evaluated the ability of Cr to protect human erythrocytes and lymphocytes against oxidative damage. Erythrocytes were challenged with model oxidants, 2, 2'-azobis(2-amidinopropane dihydrochloride (AAPH and hydrogen peroxide (H2O2 in the presence and absence of Cr. Incubation of erythrocytes with oxidant alone increased hemolysis, methemoglobin levels, lipid peroxidation and protein carbonyl content. This was accompanied by decrease in glutathione levels. Antioxidant enzymes and antioxidant power of the cell were compromised while the activity of membrane bound enzyme was lowered. This suggests induction of oxidative stress in erythrocytes by AAPH and H2O2. However, Cr protected the erythrocytes by ameliorating the AAPH and H2O2 induced changes in these parameters. This protective effect was confirmed by electron microscopic analysis which showed that oxidant-induced cell damage was attenuated by Cr. No cellular alterations were induced by Cr alone even at 20 mM, the highest concentration used. Creatinine, a by-product of Cr metabolism, was also shown to exert protective effects, although it was slightly less effective than Cr. Human lymphocytes were similarly treated with H2O2 in absence and presence of different concentrations of Cr. Lymphocytes incubated with oxidant alone had alterations in various biochemical and antioxidant parameters including decrease in cell viability and induction of DNA damage. The presence of Cr attenuated all these H2O2-induced changes in lymphocytes. Thus, Cr can function as a blood antioxidant, protecting cells from oxidative damage, genotoxicity and can potentially increase their

  18. CCR5 susceptibility to ligand-mediated down-modulation differs between human T lymphocytes and myeloid cells.

    Science.gov (United States)

    Fox, James M; Kasprowicz, Richard; Hartley, Oliver; Signoret, Nathalie

    2015-07-01

    CCR5 is a chemokine receptor expressed on leukocytes and a coreceptor used by HIV-1 to enter CD4(+) T lymphocytes and macrophages. Stimulation of CCR5 by chemokines triggers internalization of chemokine-bound CCR5 molecules in a process called down-modulation, which contributes to the anti-HIV activity of chemokines. Recent studies have shown that CCR5 conformational heterogeneity influences chemokine-CCR5 interactions and HIV-1 entry in transfected cells or activated CD4(+) T lymphocytes. However, the effect of CCR5 conformations on other cell types and on the process of down-modulation remains unclear. We used mAbs, some already shown to detect distinct CCR5 conformations, to compare the behavior of CCR5 on in vitro generated human T cell blasts, monocytes and MDMs and CHO-CCR5 transfectants. All human cells express distinct antigenic forms of CCR5 not detected on CHO-CCR5 cells. The recognizable populations of CCR5 receptors exhibit different patterns of down-modulation on T lymphocytes compared with myeloid cells. On T cell blasts, CCR5 is recognized by all antibodies and undergoes rapid chemokine-mediated internalization, whereas on monocytes and MDMs, a pool of CCR5 molecules is recognized by a subset of antibodies and is not removed from the cell surface. We demonstrate that this cell surface-retained form of CCR5 responds to prolonged treatment with more-potent chemokine analogs and acts as an HIV-1 coreceptor. Our findings indicate that the regulation of CCR5 is highly specific to cell type and provide a potential explanation for the observation that native chemokines are less-effective HIV-entry inhibitors on macrophages compared with T lymphocytes.

  19. Robot path adaptation for shared human-robot workspaces

    OpenAIRE

    Zube, Angelika; Jung, A.; Frese, Christian

    2014-01-01

    In shared human-robot workspaces, safety has to be ensured by monitoring humans and other obstacles in the robot’s environment and by performing suitable robot motions to avoid collisions. In this contribution, information from multiple depth sensors is fused in an octree representing the current obstacles in consideration of occlusions. Based on this octree, the previously planned robot path is adapted using elastic bands in order to prevent collisions with humans.

  20. Inverse correlation between PDGFC expression and lymphocyte infiltration in human papillary thyroid carcinomas

    International Nuclear Information System (INIS)

    Members of the PDGF family have been suggested as potential biomarkers for papillary thyroid carcinomas (PTC). However, it is known that both expression and stimulatory effect of PDGF ligands can be affected by inflammatory cytokines. We have performed a microarray study in a collection of PTCs, of which about half the biopsies contained tumour-infiltrating lymphocytes or thyroiditis. To investigate the expression level of PDGF ligands and receptors in PTC we measured the relative mRNA expression of all members of the PDGF family by qRT-PCR in 10 classical PTC, eight clinically aggressive PTC, and five non-neoplastic thyroid specimens, and integrated qRT-PCR data with microarray data to enable us to link PDGF-associated gene expression profiles into networks based on recognized interactions. Finally, we investigated potential influence on PDGF mRNA levels by the presence of tumour-infiltrating lymphocytes. qRT-PCR was performed on PDGFA, PDGFB, PDGFC, PDGFD, PDGFRA PDGFRB and a selection of lymphocyte specific mRNA transcripts. Semiquantitative assessment of tumour-infiltrating lymphocytes was performed on the adjacent part of the biopsy used for RNA extraction for all biopsies, while direct quantitation by qRT-PCR of lymphocyte-specific mRNA transcripts were performed on RNA also subjected to expression analysis. Relative expression values of PDGF family members were combined with a cDNA microarray dataset and analyzed based on clinical findings and PDGF expression patterns. Ingenuity Pathway Analysis (IPA) was used to elucidate potential molecular interactions and networks. PDGF family members were differentially regulated at the mRNA level in PTC as compared to normal thyroid specimens. Expression of PDGFA (p = 0.003), PDGFB (p = 0.01) and PDGFC (p = 0.006) were significantly up-regulated in PTCs compared to non-neoplastic thyroid tissue. In addition, expression of PDGFC was significantly up-regulated in classical PTCs as compared to clinically aggressive PTCs

  1. Wavefront sensorless adaptive optics ophthalmoscopy in the human eye

    OpenAIRE

    Hofer, Heidi; Sredar, Nripun; Queener, Hope; Li, Chaohong; Porter, Jason

    2011-01-01

    Wavefront sensor noise and fidelity place a fundamental limit on achievable image quality in current adaptive optics ophthalmoscopes. Additionally, the wavefront sensor ‘beacon’ can interfere with visual experiments. We demonstrate real-time (25 Hz), wavefront sensorless adaptive optics imaging in the living human eye with image quality rivaling that of wavefront sensor based control in the same system. A stochastic parallel gradient descent algorithm directly optimized the mean intensity in ...

  2. Modulatory Effect of Distillate of Ocimum sanctum Leaf Extract(Tulsi)on Human Lymphocytes Against Genotoxicants

    Institute of Scientific and Technical Information of China (English)

    DIPANWITA DUTTA; S.SARAVANA DEVI; K.KRISHNAMURTHI; KOEL KUMAR; PRIYANKA VYAS; P.L.MUTHAL; P.NAOGHARE; T.CHAKRABARTI

    2007-01-01

    Objective To study the modulatory effect of distillate of Ocimum sanctum(traditionally known as Tulsi)leaf extract (DTLE)on genotoxicants.Methods In the present investigation,we studied the antigenotoxic and anticlastogenic effect of distillate of Tlulsi leaf extract on(i)human polymorphonuclear leukocytes by evaluating the DNA strand break without metabolic activation against mitomycin C(MMC)and hexavalent chromium(Cr+6)and(ii)human peripheral lymphocytes (in vitro)with or without metabolic activation against mitomycin C(MMC),hexavalent chromium(Cr+6)and B[a]P by evaluating chromosomal aberration(CA)and micronucleus assay(MN).Three different doses of DTLE,50 μL/mL,100 μL/mL,and 200 μL/mL were selected on the basis of cytotoxicity assay and used for studying DNA strand break,chromosomal aberration and micronucleus emergence.The following positive controls were used for inducing genotoxicity and clastogenicity:MMC(0.29 μmol/L)for DNA strand break,chromosomal aberration and 0.51 μmol/L for micronucleus assay;Potassium dichromate(Cr+6)600 μmol/L for DNA strand break and 5 μmol/L for chromosomal aberration and micronucleus assay;Benzo[a]pyrene(30 μmol/L)for chromosomal aberration and 40 μmol/L for micronucleus assay.The active ingredients present in the distillate of Tulsi leaf extract were identified by HPLC and LC-MS.Results Mitomycin C(MMC)and hexavalent chromium(Cr+6) induced statistically significant DNA strand break of respectively 69%and 71%(P<0.001)as revealed by fluorometric analysis of DNA unwinding.Furthermore,thedamage could be protected with DTLE(50 μL/mL,100 μL/mL,and 200 μL/mL) on simultaneous treatment.Chromosomal aberration and micronucleus formation induced by MMC,Cr+6 and B[a]P were significantly protected(P<0.001)by DTLE with and without metabolic activation.Conclusion Distillate of Tulsi leaf extract possesses antioxidants contributed mainly by eugenol,luteolin and apigenin as identified by LC-MS.These active ingredients may have

  3. Human Adaptation to the Control of Fire

    OpenAIRE

    Wrangham, Richard W.; Carmody, Rachel Naomi

    2010-01-01

    Charles Darwin attributed human evolutionary success to three traits. Our social habits and anatomy were important, he said, but the critical feature was our intelligence, because it led to so much else, including such traits as language, weapons, tools, boats, and the control of fire. Among these, he opined, the control of fire was “probably the greatest ever [discovery] made by man, excepting language.” Despite this early suggestion that the control of fire was even more important than tool...

  4. Protective effect of peach kernel extracts on radiation-induced DNA damage in human blood lymphocytes in the comet assay

    International Nuclear Information System (INIS)

    The alkaline single-cell gel electrophoresis (SCGE) assay, the comet assay, has been applied to the detection of DNA damage from a number of chemical and biological factors in vivo and in vitro. The comet assay is a novel method to assess DNA single-strand breaks, alkali-labile sites in individual cells. We evaluated the effect of peach kernel extracts on radiation-induced DNA damage in human blood lymphocytes using the comet assay. The lymphocytes, with or without pretreatment of the extracts, were exposed to 0, 0.1, 0.3, 0.5, 1.0 and 2.0 Gy of 60Co gamma ray. Significantly increased tail moment, which was a marker of DNA strand breaks in the comet assay, showed an excellent dose-response relationship. The treatment of the peach kernel extracts prominently reduced the DNA damage in irradiated groups compared to that in non-treated control groups. The result indicated that the extracts showed radioprotective effect on lymphocyte DNA when assessed by the comet assay

  5. Long-term increases in lymphocytes and platelets in human T-lymphotropic virus type II infection.

    Science.gov (United States)

    Bartman, Melissa T; Kaidarova, Zhanna; Hirschkorn, Dale; Sacher, Ronald A; Fridey, Joy; Garratty, George; Gibble, Joan; Smith, James W; Newman, Bruce; Yeo, Anthony E; Murphy, Edward L

    2008-11-15

    Human T-lymphotropic viruses types I and II (HTLV-I and HTLV-II) cause chronic infections of T lymphocytes that may lead to leukemia and myelopathy. However, their long-term effects on blood counts and hematopoiesis are poorly understood. We followed 151 HTLV-I-seropositive, 387 HTLV-II-seropositive, and 799 HTLV-seronegative former blood donors from 5 U.S. blood centers for a median of 14.0 years. Complete blood counts were performed every 2 years. Multivariable repeated measures analyses were conducted to evaluate the independent effect of HTLV infection and potential confounders on 9 hematologic measurements. Participants with HTLV-II had significant (P platelet counts (+16 544 and +21 657 cells/mm(3); P platelet count and lymphocyte counts, and to increases in MCV and monocytes. Sex, race, smoking, and alcohol consumption all had significant effects on blood counts. The HTLV-II effect on lymphocytes is novel and may be related to viral transactivation or immune response. HTLV-I and HTLV-II associations with higher platelet counts suggest viral effects on hematopoietic growth factors or cytokines.

  6. Broad T-cell receptor repertoire in T-lymphocytes derived from human induced pluripotent stem cells.

    Directory of Open Access Journals (Sweden)

    Chia-Wei Chang

    Full Text Available Human induced pluripotent stem cells (hiPSCs have enormous potential for the treatment of inherited and acquired disorders. Recently, antigen-specific T lymphocytes derived from hiPSCs have been reported. However, T lymphocyte populations with broad T cell receptor (TCR diversity have not been generated. We report that hiPSCs derived from skin biopsy are capable of producing T lymphocyte populations with a broad TCR repertoire. In vitro T cell differentiation follows a similar developmental program as observed in vivo, indicated by sequential expression of CD7, intracellular CD3 and surface CD3. The γδ TCR locus is rearranged first and is followed by rearrangement of the αβ locus. Both γδ and αβ T cells display a diverse TCR repertoire. Upon activation, the cells express CD25, CD69, cytokines (TNF-α, IFN-γ, IL-2 and cytolytic proteins (Perforin and Granzyme-B. These results suggest that most, if not all, mechanisms required to generate functional T cells with a broad TCR repertoire are intact in our in vitro differentiation protocol. These data provide a foundation for production of patient-specific T cells for the treatment of acquired or inherited immune disorders and for cancer immunotherapy.

  7. Comparison of Changes in Immunological Parameters in Human Lymphocytes in 2D Versus 3D Clinostats-Goal Towards Microgravity Analog Calibration for Future Space Experiments

    Science.gov (United States)

    Sundaresan, Alamelu; Russomano, Thais; Pellis, Neal R.

    2008-06-01

    Exposure to microgravity may produce changes in the performance of the immunological system at the cellular level as well as in the major physiological systems of the body. Studies in true spaceflight and similar studies in 2D clinostats (Rotating wall vessels) related to decreased immune function in astronaut blood and normal human lymphocytes indicate a decrease in cell proliferation, T cell activation, locomotion and altered lymphocyte signal transduction (Sundaresan and Pellis, 2008, Sundaresan et al., 2004). The present study was designed to investigate whether the proliferation and viability of lymphocytes are reduced by exposure to rotation in a 3D-Clinostat, which is used to simulate microgravity for cells.

  8. Changes in membrane receptors of B and T human lymphocytes exposed to 60Co gamma rays

    International Nuclear Information System (INIS)

    The present report describes the effect of 50 to 2500 rad of 60Co gamma rays on the membrane receptors of B and T lymphocytes. Surface membrane immunoglobulins and Fc receptors were used as markers for B cells, while the formation of rosettes with sheep red blood cells was used as a marker for T cells. The effect of radiation is expressed as the percentage of viable cells that bear membrane receptors. The radiation effects were studied after 2, 24, 36 hr of culture. For B lymphocytes no reduction in SmIg and Fc receptors was seen 2 hr after radiation, whereas a dose-related reduction was observed after 24 and 36 hr. A dose-related inhibition of the ''capping'' of SmIg was observed. For T lymphocytes a reduction of E rosette formation was seen starting 2 hr after irradiation. Electron microscopy of separated B and T cells showed a higher sensitivity of T cells as well as a different structural arrangement of the chromatin as a consequence of radiation damage. These data suggest differentiated behavior of B and T lymphocyte membrane receptors after exposure to radiation

  9. N-(4-F-18-Fluorobenzoyl)Interleukin-2 for PET of Human-Activated T Lymphocytes

    NARCIS (Netherlands)

    Di Gialleonardo, Valentina; Signore, Alberto; Glaudemans, Andor W. J. M.; Dierckx, Rudi A. J. O.; De Vries, Erik F. J.

    2012-01-01

    Interleukin-2 (IL2) binds with high affinity to the IL2 receptors overexpressed on activated T lymphocytes in various pathologic conditions. Radiolabeling of IL2 with a positron-emitting isotope could provide a tool for noninvasive PET of activated T cells in immune-mediated diseases. We report the

  10. Heritability of Susceptibility to Ionizing Radiation-Induced Apoptosis of Human Lymphocyte Subpopulations

    International Nuclear Information System (INIS)

    Purpose: To evaluate the heritability of intrinsic radiosensitivity, the induction of apoptosis in lymphocyte subpopulations was determined on samples from related individuals belonging to large kindred families. Methods and Materials: Quiescent lymphocytes from 334 healthy individuals were gamma-irradiated in vitro. Apoptosis was determined 18 h after irradiation by eight-color flow cytometry. Radiosensitivity was quantified from dose-effect curves. Intrafamilial correlations and heritability were computed for 199 father-mother-offspring trios using the programs SOLAR (Sequential Oligogenic Linkage Analysis Routines) and SAGE (Statistical Analysis for Genetic Epidemiology). Segregation analyses were conducted using SAGE. Results: Marked differential susceptibility of naive and memory T lymphocytes was demonstrated. Also, although age and gender were significant covariates, their effects only accounted for a minor part of the inter-individual variation. Parent-offspring and sib-sib correlations were significant for the radiosensitivity of B cells, T4, and T8 and of effector memory T4 and T8 subpopulations. In the T4-effector memory subpopulation, the phenotype showed correlations most consistent with dominant or additive genetic effects, and the results of the segregation analysis were consistent with the contribution of a bi-allelic dominant locus. Conclusions: Heritability was demonstrated for the susceptibility to ionizing radiation-induced apoptosis of lymphocyte populations, and the segregation of the T4-effector memory radiosensitivity phenotype was consistent with a simple mendelian transmission model involving one major gene

  11. A double antibody radioimmunoassay for measurement of IgG, IgA and IgM synthesized by human lymphocytes in vitro.

    Directory of Open Access Journals (Sweden)

    Asano,Taro

    1981-11-01

    Full Text Available To investigate cellular interactions between human T and B lymphocytes in various diseases, we established a technique to prove terminal differentiation of B lymphocytes into immunoglobulin synthesizing and secreting cells. We also established a double antibody radioimmunoassay to measure the amount of IgG, IgA and IgM synthesized and secreted in culture supernatants. Purified immunoglobulins were obtained from sera of patients with myeloma or macroglobulinemia. The peripheral blood lymphocytes from 25 normal individuals had the geometric mean synthetic rates of 1886 ng for IgG, 1607 ng for IgA and 1173 ng for IgM per 1 X 10(6 cells when cultured for nine days in the presence of pokeweed mitogen. The method is simple and sensitive, and is thought to be useful for examining human lymphocyte function in vitro.

  12. Behavior of exposed human lymphocytes to a neutron beam of the reactor TRIGA Mark III

    International Nuclear Information System (INIS)

    Excessive exposure to ionizing radiation occurs in people who require radiation treatment, also in those for work can come to receive doses above the permitted levels. A third possibility of exposure is the release of radioactive material in which the general population is affected. Most of the time the exhibition is partial and only rarely occurs throughout the body. For various reasons, situations arise where it is impossible to determine by conventional physical methods, the amount of radiation you were exposed to the affected person and in these cases where the option to follow is the Biological Dosimetry, where the analysis of chromosomes dicentrics is used to estimate the dose of ionizing radiation exposure. A calibration curve is generated from in vitro analysis of dicentric chromosome, which are found in human lymphocytes, treated with different types and doses of radiation. The dicentric is formed from two lesions, one on each chromosome and their union results in a structure having two centromeres, acentric fragment with her for the union of several chromosomes leads to more complex structures as tri-centric s, tetra or penta-centric s, which have the same origin. The dose-response curve is estimated by observing the frequency of dicentrics and extrapolated to a dose-effect curve previously established, for which it is necessary that each lab has its own calibration curves, taking into account that for a Let low radiation, dose-effect curve follows a linear-quadratic model Y=C + αD + βD. The production of dicentric chromosomes with a high Let, was studied using a beam of neutrons generated in the reactor TRIGA Mark III with an average energy of 1 MeV, adjusting the linear model Y=αD. The dose-response relationship is established in blood samples from the same donor, the coefficient α of the dose-response is Y = (0.3692 ± 0.011 * D), also shows that saturation is reached in system 4 Gy. (Author)

  13. The Biological Effectiveness of Different Radiation Qualities for the Induction of Chromosome Damage in Human Lymphocytes

    Science.gov (United States)

    Hada, M.; George, Kerry; Cucinotta, F. A.

    2011-01-01

    Chromosome aberrations were measured in human peripheral blood lymphocytes after in vitro exposure to Si-28-ions with energies ranging from 90 to 600 MeV/u, Ti-48-ions with energies ranging from 240 to 1000 MeV/u, or to Fe-56-ions with energies ranging from 200 to 5,000 MeV/u. The LET of the various Si beams in this study ranged from 48 to 158 keV/ m, the LET of the Ti ions ranged from 107 to 240 keV/micron, and the LET of the Fe-ions ranged from 145 to 440 keV/ m. Doses delivered were in the 10- to 200-cGy range. Dose-response curves for chromosome exchanges in cells at first division after exposure, measured using fluorescence in situ hybridization (FISH) with whole-chromosome probes, were fitted with linear or linear-quadratic functions. The relative biological effectiveness (RBE) was estimated from the initial slope of the dose-response curve for chromosome damage with respect to gamma-rays. The estimates of RBEmax values for total chromosome exchanges ranged from 4.4+/-0.4 to 31.5+/-2.6 for Fe ions, 21.4+/-1.7 to 28.3+/-2.4 for Ti ions, and 11.8+/-1.0 to 42.2+/-3.3 for Si ions. The highest RBEmax value for Fe ions was obtained with the 600 MeV/u beam, the highest RBEmax value for Ti ions was obtained 1000 MeV/u beam, and the highest RBEmax value for Si ions was obtained with the 170 MeV/u beam. For Si and Fe ions the RBEmax values increased with LET, reaching a maximum at about 180 keV/micron for Fe and about 100 keV/micron for Si, and decreasing with further increase in LET. Additional studies for low doses Si-28-ions down to 0.02 Gy will be discussed.

  14. Inhibition of clinical human immunodeficiency virus (HIV) type 1 isolates in primary CD4+ T lymphocytes by retroviral vectors expressing anti-HIV genes.

    OpenAIRE

    Vandendriessche, T.; Chuah, M. K.; L. Chiang; Chang, H K; Ensoli, B; Morgan, R A

    1995-01-01

    Gene therapy may be of benefit in human immunodeficiency virus type 1 (HIV-1)-infected individuals by virtue of its ability to inhibit virus replication and prevent viral gene expression. It is not known whether anti-HIV-1 gene therapy strategies based on antisense or transdominant HIV-1 mutant proteins can inhibit the replication and expression of clinical HIV-1 isolates in primary CD4+ T lymphocytes. We therefore transduced CD4+ T lymphocytes from uninfected individuals with retroviral vect...

  15. Microwell Devices with Finger-like Channels for Long-Term Imaging of HIV-1 Expression Kinetics in Primary Human Lymphocytes

    OpenAIRE

    Razooky, Brandon; Gutierrez, Edgar; Terry, Valeri H.; Spina, Celsa A; Groisman, Alex; Weinberger, Leor

    2012-01-01

    A major obstacle in the treatment of human immunodeficiency virus type 1 (HIV-1) is a sub-population of latently infected CD4+ T lymphocytes. The cellular and viral mechanisms regulating HIV-1 latency are not completely understood, and a promising technique for probing the regulation of HIV-1 latency is single-cell time-lapse microscopy. Unfortunately, CD4+ T lymphocytes rapidly migrate on substrates and spontaneously detach, making them exceedingly difficult to track and hampering single-cel...

  16. Chromosome aberrations and sister chromatid exchanges in cultured human lymphocytes treated with sodium metabisulfite, a food preservative.

    Science.gov (United States)

    Rencüzogullari, E; Ila, H B; Kayraldiz, A; Topaktaş, M

    2001-02-20

    The aim of this study was to investigate the ability of sodium metabisulfite (SMB) which is used as an antimicrobial substance in food, to induce chromosome aberrations (CA) and sister chromatid exchanges (SCE) in human lymphocytes. SMB-induced CAs and SCEs at all concentrations (75, 150 and 300 microg/ml) and treatment periods (24 and 48h) dose-dependently. However, SMB decreased the replication index (RI) and the mitotic index (MI) at the concentrations of 150 and 300 microg/ml for 24 and 48h treatment periods. This decrease was dose-dependent as well.

  17. [Effect of x-rays on the intracellular transport of thymidine in human lymphocytes stimulated by phytohemagglutinins].

    Science.gov (United States)

    Catena, C; Mattoni, A

    1984-08-31

    The effect of X-irradiation on thymidine transport in human lymphocytes PHA stimulated was investigated. Mediated transport sistem, the predominant mechanism at low extracellular concentration of thymidine (less than 10(-7) M) in the medium is highly radiosensitive. The transport sistem was damaged considerably by high doses of X-rays (at least until 10 Krad); the decrease of thymidine uptake was a function of the time of incubation after irradiation. It suggest that repair mechanisms are not involved at high doses of X-rays within 120 minutes of incubation. PMID:6497982

  18. Chromosomal aberrations in lymphocytes predict human cancer: a report from the European Study Group on Cytogenetic Biomarkers and Health (ESCH)

    DEFF Research Database (Denmark)

    Hagmar, L; Bonassi, S; Strömberg, U;

    1998-01-01

    . No association was seen between the SCEs or the MN frequencies and subsequent cancer incidence/mortality. The present study further supports our previous observation on the cancer predictivity of the CA biomarker, which seems to be independent of age at test, gender, and time since test. The risk patterns were...... similar within each national cohort. This result suggests that the frequency of CAs in peripheral blood lymphocytes is a relevant biomarker for cancer risk in humans, reflecting either early biological effects of genotoxic carcinogens or individual cancer susceptibility....

  19. gp140, the C3d receptor of human B lymphocytes, is also the Epstein-Barr virus receptor.

    OpenAIRE

    Frade, R; Barel, M; Ehlin-Henriksson, B.; Klein, G

    1985-01-01

    The relationship between gp140, the membrane C3d receptor (CR2) of human B lymphocytes, and the Epstein-Barr virus receptor (EBVR) was analyzed by using the polyclonal anti-gp140, previously prepared by immunizing rabbits with highly purified gp140 (isolated by some of us) from CR2/EBVR-positive Raji cells. Polyclonal anti-gp72, a C3-binding membrane component, not related to the EBVR but also expressed on the Raji cell surface, was used as a control. Binding of rabbit IgG and EBV on cells wa...

  20. In vitro radiosensitivity of human fresh T-lymphocytes by colony formation assay using PHA and recombinant Interleukin-2

    International Nuclear Information System (INIS)

    In vitro culture conditions for colony formation of human fresh peripheral T-cells using phytohemagglutinin (PHA) and recombinant Interleukin-2 are defined. Peripheral lymphocytes, from six individuals, were exposed to X or gamma rays in vitro, and dose-survival curves were obtained. The results showed typical sigmoid curves similar to those observed when other mammalian cells are exposed to radiation. The D10 (dose required to kill 90 % of the cells) was found to be 3.0 to 3.5 Gy. (author)

  1. In vitro radiosensitivity of human fresh T-lymphocytes by colony formation assay using PHA and recombinant interleukin-2

    International Nuclear Information System (INIS)

    In vitro culture conditions for colony formation of human fresh peripheral T-cells using PHA and recombinant Interleukin-2 are defined. Peripheral lymphocytes, from six individuals, were exposed to X or gamma rays in vitro, and dose-survival curves were obtained. The results showed typical sigmoid curves similar to those observed when other mammalian cells are exposed to radiation. The D10 (dose required to kill 90 % of the cells) was found to be 3.0 to 3.5 Gy. (author)

  2. Application of Comet assay to assess the effects of white bean meal on DNA of human lymphocytes

    OpenAIRE

    Luciana Lopes Silva Pereira; Silvana Marcussi; Lívia Cabral Sátiro; Chrystian Araujo Pereira; Larissa Fonseca Andrade; Lisete Chamma Davide; Custódio Donizete dos Santos

    2012-01-01

    This study was conducted to evaluate the potential induction of genotoxic effects of white bean flour using the Comet assay. The test was conducted with human lymphocytes present in whole blood immediately after collection, by incubation with white bean flour in three concentrations (3.92, 9.52 and 18.18 mg/mL) at 37 ºC for 4 h followed by preparation of slides. Samples were considered positive (above 20% damage) when the damage observed to cellular DNA was higher than the negative control. N...

  3. Genetic Evidence of Human Adaptation to a Cooked Diet

    OpenAIRE

    Carmody, Rachel N.; Dannemann, Michael; Briggs, Adrian W; Nickel, Birgit; Groopman, Emily E.; Wrangham, Richard W.; Kelso, Janet

    2016-01-01

    Humans have been argued to be biologically adapted to a cooked diet, but this hypothesis has not been tested at the molecular level. Here, we combine controlled feeding experiments in mice with comparative primate genomics to show that consumption of a cooked diet influences gene expression and that affected genes bear signals of positive selection in the human lineage. Liver gene expression profiles in mice fed standardized diets of meat or tuber were affected by food type and cooking, but n...

  4. Adaptive Response to ionizing Radiation Induced by Low Doses of Gamma Rays in Human Lymphoblastoid Cell Lines

    International Nuclear Information System (INIS)

    When cells are exposed to low doses of a mutagenic or clastogenic agents, they often become less sensitive to the effects of a higher does administered subsequently. Such adaptive responses were first described in Escherichia coli and mammalian cells to low doses of an alkylating agent. Since most of the studies have been carried out with human lymphocytes, it is urgently necessary to study this effect in different cellular systems. Its relation with inherent cellular radiosensitivity and underlying mechanism also remain to be answered. In this study, adaptive response by 1 cGy of gamma rays was investigated in three human lymphoblastoid cell lines which were derived from ataxia telangiectasia homozygote, ataxia telangiectasia heterozygote, and normal individual. Experiments were carried out by delivering 1 cGy followed by 50 cGy of gamma radiation and chromatid breaks were scored as an endpoint. The results indicate that prior exposure to 1 cGy of gamma rays reduces the number of chromatid breaks induced by subsequent higher does (50 cGy). The expression of this adaptive response was similar among three cell lines despite of their different radiosensitivity. When 3-aminobenzamide, an inhibitor of poly (ADP-ribose) polymerase, was added after 50 cGy, adaptive responses were abolished in all the tested cell lines. Therefore it is suggested that the adaptive response can be observed in human lymphoblastoid cell lines. Which was first documented through this study. The expression of adaptive response was similar among the cell lines regardless of their radiosensitivity. The elimination of the adaptive response by 3-aminobenzamide is consistent with the proposal that this adaptive response is the result of the induction of a certain chromosomal repair mechanism

  5. Sequencing of 50 human exomes reveals adaptation to high altitude

    DEFF Research Database (Denmark)

    Yi, Xin; Liang, Yu; Huerta-Sanchez, Emilia;

    2010-01-01

    Residents of the Tibetan Plateau show heritable adaptations to extreme altitude. We sequenced 50 exomes of ethnic Tibetans, encompassing coding sequences of 92% of human genes, with an average coverage of 18x per individual. Genes showing population-specific allele frequency changes, which...... represent strong candidates for altitude adaptation, were identified. The strongest signal of natural selection came from endothelial Per-Arnt-Sim (PAS) domain protein 1 (EPAS1), a transcription factor involved in response to hypoxia. One single-nucleotide polymorphism (SNP) at EPAS1 shows a 78% frequency...... difference between Tibetan and Han samples, representing the fastest allele frequency change observed at any human gene to date. This SNP's association with erythrocyte abundance supports the role of EPAS1 in adaptation to hypoxia. Thus, a population genomic survey has revealed a functionally important locus...

  6. Wavefront sensorless adaptive optics ophthalmoscopy in the human eye

    Science.gov (United States)

    Hofer, Heidi; Sredar, Nripun; Queener, Hope; Li, Chaohong; Porter, Jason

    2011-07-01

    Wavefront sensor noise and fidelity place a fundamental limit on achievable image quality in current adaptive optics ophthalmoscopes. Additionally, the wavefront sensor `beacon' can interfere with visual experiments. We demonstrate real-time (25 Hz), wavefront sensorless adaptive optics imaging in the living human eye with image quality rivaling that of wavefront sensor based control in the same system. A stochastic parallel gradient descent algorithm directly optimized the mean intensity in retinal image frames acquired with a confocal adaptive optics scanning laser ophthalmoscope (AOSLO). When imaging through natural, undilated pupils, both control methods resulted in comparable mean image intensities. However, when imaging through dilated pupils, image intensity was generally higher following wavefront sensor-based control. Despite the typically reduced intensity, image contrast was higher, on average, with sensorless control. Wavefront sensorless control is a viable option for imaging the living human eye and future refinements of this technique may result in even greater optical gains.

  7. Emigrating Beyond Earth Human Adaptation and Space Colonization

    CERN Document Server

    Smith, Cameron M

    2012-01-01

    For four million years humankind has been actively expanding geographically and in doing so has adapted to a wide variety of hostile environments. Now we are looking towards the ultimate adaptation - the colonization of space. Emigrating Beyond Earth illustrates that this is not a technocratic endeavor, but a natural continuation of human evolution; a journey not just for the engineer and rocket scientist, but for everyman. Based on the most current understanding of our universe, human adaptation and evolution, the authors explain why space colonization must be planned as an adaptation to, rather than the conquest of, space. Emigrating Beyond Earth argues that space colonization is an insurance policy for our species, and that it isn't about rockets and robots, it's about humans doing what we've been doing for four million years: finding new places and new ways to live. Applying a unique anthropological approach, the authors outline a framework for continued human space exploration and offer a glimpse of a po...

  8. The human vestibulo-ocular reflex : effects of adaptation

    NARCIS (Netherlands)

    L.J.J.M. Boumans (Leon)

    1982-01-01

    textabstractThis thesis systematically investigates the influence of adaptation on the human VOR-response. Various types of angular acceleration around the vertical axis are used to determine the time constants of the VOR-system. Care is taken as far as possible to avoid fatigue, habituation and the

  9. Localizing recent adaptive evolution in the human genome

    DEFF Research Database (Denmark)

    Williamson, Scott H; Hubisz, Melissa J; Clark, Andrew G;

    2007-01-01

    , clusters of olfactory receptors, genes involved in nervous system development and function, immune system genes, and heat shock genes. We also observe consistent evidence of selective sweeps in centromeric regions. In general, we find that recent adaptation is strikingly pervasive in the human genome...

  10. Genomic signatures reveal geographic adaption and human selection in cattle

    Science.gov (United States)

    We investigated geographic adaptation and human selection using high-density SNP data of five diverse cattle breeds. Based on allele frequency differences, we detected hundreds of candidate regions under positive selection across Holstein, Angus, Charolais, Brahman, and N'Dama. In addition to well-k...

  11. In vitro Safety Evaluation and Anticlastogenic Effect of BacoMindTM on Human Lymphocytes

    Institute of Scientific and Technical Information of China (English)

    DIPANWITA DUTTADEB; PREETI KAPOOR; R.P.DIGHE; R.PADMAJA; M.S.ANAND; P.D'SOUZA; M.DEEPAK; B.MURALI; AAMIT AGARWAL

    2008-01-01

    Objective BacoMindTM (BM) is a standardized extract of Bacopa monnieri,which belongs to the family Scrophulariaceae and is a creeping annual plant found throughout the Indian subcontinent.It has been used by Ayurvedic medicinal practitioners in India for almost 3000 years and is classified as a medharasayana,a substance which improves memory and intellect.With the widespread traditional use as well as scientific validation of Bacopa monnieri for nootropic activity,a bioactive-rich unique Phvtochemical composition-BacoMindTM was developed from B.monnieri for use as a cognition and memory enhancing agent. The present study aimed to investigate the in vitro toxicity of this formulation of BacoMindTM on human lymphocytes and to rule out its possible contribution to mutagenicity. Methods In the present investigation the active ingredients present in BM were identified and quantified by high performance liquid chromatography (HPLC)and high performance thin-layer chromatography(HPTLC).Antioxidant and anticlastogenic properties of BM were studied in vitro with and without metabolic activation.Doses of BM were chosen on the basis of mitotic index(MI)and cytokinesis-block proliferation index(CBPI).Clastogenicity assays were performed at 31.2 μg/mL,62.5 μg/mL,and 125 μg/mL,while the Salmonella reverse mutation assay (Ames test)was performed at doses of 61.72,185.18,555.55,1666.67,and 5000.00 μg/plate. Results HPLC and HPTLC analysis of BM revealed the presence of bacosidc A3,bacopaside I,bacopaside Ⅱ,iujubogenin isomer of bacopasaponin C,bacosine,luteolin,apigemn,bacosine,and β-sitosterol D glucoside.BM demonstrated significant antioxidant activity.The number of chromosomal aberrations and the frequency of micronuclei induced by BM were not statistically significant up to a dose of 62.5 μg/mL.A subsequent dose of 125 μg/mL prior to metabolic activation induced mild clastogenicity,but it was found to be biologically insignificant as this effect was not seen post

  12. Natural and artefactual aneuploidy in human lymphocytes in extreme old age.

    Science.gov (United States)

    Lezhava, T; Khmaladze, E; Lokhadze, T; Buadze, T

    2008-04-01

    At present it is generally believed that aging is accompanied by an increase in the numbers of cells with altered chromosome sets. However, the problem of aneuploidy in extreme old age (80 years and over) has hardly been subjected to systematic investigation. The purpose of this study was to examine quantitative chromosome changes and relationship between "artefactual" and "natural" aneuploidy in subjects from 80 to 114 years of age using karyotype analyses. Chromosomes were studied in 1136 karyotypes of relatively round metaphases from 40 lymphocyte cultures obtained from 40 apparently normal subjects aged from 80 to 114 ( including 26 men and 14 women). 964 karyotypes from 48 donors aged 20 to 48 served as control. Lymphocytes were cultivation by modification method (Lezhava, 2006). It is suggested that the probability of natural aneuploidy rises substantially among elderly women; while that of artefactual aneuploidy is increased among elderly men; the problem of natural aneuploidy in males remains unclear.

  13. Effects of Ephedrine and Ephedra fragilis Crude Extracts on Human Peripheral Lymphocytes

    Directory of Open Access Journals (Sweden)

    E Attard

    2009-01-01

    Full Text Available Ephedra fragilis Desf. (Ephedraceae, a locally cultivated medicinal plant, is a source of ephedrine and pseudoephedrine, two important alkaloids, which have long played an important pharmacological role. The present study investigated the in vitro effects of ephedrine and the Ephedra branch extract on unstimulated lymphocytes. Ephedra alkaloids were extracted from various plant parts and after phytochemical analysis, the brine shrimp lethality test was used to determine the activity of the extracts. The LC 50 of the branch extract was 581.395 μg/ml, showing no statistical difference from that of ephedrine (208.203 μg/ml. The ephedrine and extract did not show toxic effects on lymphocytes but exhibited immunostimulant activity. Although ephedrine cannot be used as an immune booster, it can be used as a lead drug for further immunological research.

  14. Effects of low dose radiation on repair processes in human lymphocytes

    International Nuclear Information System (INIS)

    DNA excision repair was investigated in lymphocytes of persons occupationally exposed to low dose radiation of 222Rn. Autoradiographic studies of unscheduled DNA synthesis and measurement of 3H-thymidine incorporation by repair replication into double stranded and single-strand containing DNA fractions obtained by BND cellulose chromatography seem to indicate a stimulatory effect of repeated low dose radiation on repair enzymes. (author)

  15. Dengue virus-specific cross-reactive CD8+ human cytotoxic T lymphocytes.

    OpenAIRE

    Bukowski, J F; Kurane, I; Lai, C J; Bray, M; Falgout, B; Ennis, F A

    1989-01-01

    Stimulation with live dengue virus of peripheral blood mononuclear cells from a dengue virus type 4-immune donor generated virus-specific, serotype-cross-reactive, CD8+, class I-restricted cytotoxic T lymphocytes (CTL) capable of lysing dengue virus-infected cells and cells pulsed with dengue virus antigens of all four serotypes. These CTL lysed autologous fibroblasts infected with vaccinia virus-dengue virus recombinant viruses containing the E gene or several nonstructural dengue virus type...

  16. The in vitro genotoxic effects of a commercial formulation of alpha-cypermethrin in human peripheral blood lymphocytes.

    Science.gov (United States)

    Kocaman, Ayşe Yavuz; Topaktaş, Mehmet

    2009-01-01

    alpha-Cypermethrin, a highly active pyrethroid insecticide, is effective against a wide range of insects encountered in agriculture and animal husbandry. The potential genotoxicity of a commercial formulation of alpha-cypermethrin (Fastac 100 EC, containing 10% alpha-cypermethrin as the active ingredient) on human peripheral lymphocytes was examined in vitro by sister chromatid exchange (SCE), chromosomal aberrations (CAs), and micronucleus (MN) tests. The human lymphocytes were treated with 5, 10, 15, and 20 microg/ml of alpha-cypermethrin for 24- and 48-hr. alpha-Cypermethrin induced SCEs and CAs significantly at all concentrations and treatment times and MN formation was significantly induced at 5 and 10 microg/ml of alpha-cypermethrin when compared with both the control and solvent control. Binuclear cells could not be detected sufficiently in the highest two concentration of alpha-cypermethrin (15 and 20 microg/ml) for both the 24- and 48-hr treatment times. alpha-Cypermethrin decreased the proliferation index (PI) at three high concentrations (10, 15, and 20 microg/ml) for both treatment periods as compared with the control groups. In addition, alpha-cypermethrin reduced both the mitotic index (MI) and nuclear division index (NDI) significantly at all concentrations for two treatment periods. The PI and MI were reduced by alpha-cypermethrin in a concentration-dependent manner during both treatment times. In general, alpha-cypermethrin showed higher cytotoxic and cytostatic effects than positive control (MMC) at the two highest concentrations for the 24- and 48-hr treatment periods. The present study is the first to report the genotoxic and cytotoxic effects of commercial formulation of alpha-cypermethrin in peripheral blood lymphocytes.

  17. Radioprotective effect of methanolic root extract of Loeseneriella arnottiana on radiation induced DNA damage in human lymphocytes in vitro

    International Nuclear Information System (INIS)

    Intense exposure to ionization radiation by accidental, occupational or therapeutical purpose causes cellular damage mainly by formation of excessive reactive oxygen species (ROS) or by free radicals. Humans are intentionally exposed to ionising radiation for diagnostic or therapeutic purposes. The use of ionising radiation in cancer therapy may lead to transient and/or permanent injury to normal tissues within the treatment field. To increase the therapeutic index of radiation therapy, various modes of radioprotection have been developed that selectively reduce cytotoxic effects to normal tissues. Because radiation-induced cellular damage is attributed primarily to the harmful effects of free radicals, molecules with radical scavenging properties are particularly promising as radioprotectors. Loeseneriella arnottiana, a member of family Hippocrateaceae, is a climbing shrub used by traditional medicine practitioners. To study the antioxidant activity and radioprotective effect of methanolic root extract of Loeseneriella arnottiana against electron beam radiation induced DNA damage in human lymphocytes. Loeseneriella arnottiana roots were dried and extracted using methanol by solvent extraction method. Antioxidant activity was measured by DPPH method. DNA damage was assessed by comet assay parameters. The lymphocytes were incubated for one hour with two different concentrations 10 μg and 50 μg of root extract before exposure to 2 Gy electron beam radiation. 30 μg of methanolic root extract of Loeseneriella arnottiana exhibited 96% radical scavenging activity comparable to 15 μg of ascorbic acid. In reducing power assay it showed dose dependent increase in absorbance indicating that extract is capable of donating hydrogen atoms. Pretreatment of lymphocytes with 10 μg and 50 μg of root extract before irradiation resulted in reduction in the Comet length, Olive tail moment, percentage of DNA in tail when compared to the radiation control group. Results of this

  18. Induction and repair of DNA damage measured by the comet assay in human T lymphocytes separated by immunomagnetic cell sorting.

    Science.gov (United States)

    Bausinger, Julia; Speit, Günter

    2014-11-01

    The comet assay is widely used in human biomonitoring to measure DNA damage in whole blood or isolated peripheral blood mononuclear cells (PBMC) as a marker of exposure to genotoxic agents. Cytogenetic assays with phytohemagglutinin (PHA)-stimulated cultured T lymphocytes are also frequently performed in human biomonitoring. Cytogenetic effects (micronuclei, chromosome aberrations, sister chromatid exchanges) may be induced in vivo but also occur ex vivo during the cultivation of lymphocytes as a consequence of DNA damage present in lymphocytes at the time of sampling. To better understand whether DNA damage measured by the comet assay in PBMC is representative for DNA damage in T cells, we comparatively investigated DNA damage and its repair in PBMC and T cells obtained by immunomagnetic cell sorting. PBMC cultures and T cell cultures were exposed to mutagens with different modes of genotoxic action and DNA damage was measured by the comet assay after the end of a 2h exposure and after 18h post-incubation. The mutagens tested were methyl methanesulfonate (MMS), (±)-anti-B[a]P-7,8-dihydrodiol-9,10-epoxide (BPDE), 4-nitroquinoline-1-oxide (4NQO), styrene oxide and potassium bromate. MMS and potassium bromate were also tested by the modified comet assay with formamido pyrimidine glycosylase (FPG) protein. The results indicate that the mutagens tested induce DNA damage in PBMC and T cells in the same range of concentrations and removal of induced DNA lesions occurs to a comparable extent. Based on these results, we conclude that the comet assay with PBMC is suited to predict DNA damage and its removal in T cells.

  19. Characterization of human γδ T lymphocytes infiltrating primary malignant melanomas.

    Directory of Open Access Journals (Sweden)

    Adriana Cordova

    Full Text Available T lymphocytes are often induced naturally in melanoma patients and infiltrate tumors. Given that γδ T cells mediate antigen-specific killing of tumor cells, we studied the representation and the in vitro cytokine production and cytotoxic activity of tumor infiltrating γδ T cells from 74 patients with primary melanoma. We found that γδ T cells represent the major lymphocyte population infiltrating melanoma, and both Vδ1(+ and Vδ2(+ cells are involved. The majority of melanoma-infiltrating γδ cells showed effector memory and terminally-differentiated phenotypes and, accordingly, polyclonal γδ T cell lines obtained from tumor-infiltrating immune cells produced IFN-γ and TNF-α and were capable of killing melanoma cell lines in vitro. The cytotoxic capability of Vδ2 cell lines was further improved by pre-treatment of tumor target cells with zoledronate. Moreover, higher rate of γδ T cells isolation and percentages of Vδ2 cells correlate with early stage of development of melanoma and absence of metastasis. Altogether, our results suggest that a natural immune response mediated by γδ T lymphocytes may contribute to the immunosurveillance of melanoma.

  20. Fluoxetine suppresses calcium signaling in human T lymphocytes through depletion of intracellular calcium stores.

    Science.gov (United States)

    Gobin, V; De Bock, M; Broeckx, B J G; Kiselinova, M; De Spiegelaere, W; Vandekerckhove, L; Van Steendam, K; Leybaert, L; Deforce, D

    2015-09-01

    Selective serotonin reuptake inhibitors, such as fluoxetine, have recently been shown to exert anti-inflammatory and immunosuppressive effects. Although the effects on cytokine secretion, proliferation and viability of T lymphocytes have been extensively characterized, little is known about the mechanism behind these effects. It is well known that Ca(2+) signaling is an important step in the signaling transduction pathway following T cell receptor activation. Therefore, we investigated if fluoxetine interferes with Ca(2+) signaling in Jurkat T lymphocytes. Fluoxetine was found to suppress Ca(2+) signaling in response to T cell receptor activation. Moreover, fluoxetine was found to deplete intracellular Ca(2+) stores, thereby leaving less Ca(2+) available for release upon IP3- and ryanodine-receptor activation. The Ca(2+)-modifying effects of fluoxetine are not related to its capability to block the serotonin transporter, as even a large excess of 5HT did not abolish the effects. In conclusion, these data show that fluoxetine decreases IP3- and ryanodine-receptor mediated Ca(2+) release in Jurkat T lymphocytes, an effect likely to be at the basis of the observed immunosuppression.

  1. Adaptations to climate-mediated selective pressures in humans.

    Directory of Open Access Journals (Sweden)

    Angela M Hancock

    2011-04-01

    Full Text Available Humans inhabit a remarkably diverse range of environments, and adaptation through natural selection has likely played a central role in the capacity to survive and thrive in extreme climates. Unlike numerous studies that used only population genetic data to search for evidence of selection, here we scan the human genome for selection signals by identifying the SNPs with the strongest correlations between allele frequencies and climate across 61 worldwide populations. We find a striking enrichment of genic and nonsynonymous SNPs relative to non-genic SNPs among those that are strongly correlated with these climate variables. Among the most extreme signals, several overlap with those from GWAS, including SNPs associated with pigmentation and autoimmune diseases. Further, we find an enrichment of strong signals in gene sets related to UV radiation, infection and immunity, and cancer. Our results imply that adaptations to climate shaped the spatial distribution of variation in humans.

  2. A ROBUST ADAPTIVE VIDEO ENCODER BASED ON HUMAN VISUAL MODEL

    Institute of Scientific and Technical Information of China (English)

    Yin Hao; Zhang Jiangshan; Zhu Yaoting; Zhu Guangxi

    2003-01-01

    A Robust Adaptive Video Encoder (RAVE) based on human visual model is proposed. The encoder combines the best features of Fine Granularity Scalable (FGS) coding, framedropping coding, video redundancy coding, and human visual model. According to packet loss and available bandwidth of the network, the encoder adjust the output bit rate by jointly adapting quantization step-size instructed by human visual model, rate shaping, and periodically inserting key frame. The proposed encoder is implemented based on MPEG-4 encoder and is compared with the case of a conventional FGS algorithm. It is shown that RAVE is a very efficient robust video encoder that provides improved visual quality for the receiver and consumes equal or less network resource. Results are confirmed by subjective tests and simulation tests.

  3. A ROBUST ADAPTIVE VIDEO ENCODER BASED ON HUMAN VISUAL MODEL

    Institute of Scientific and Technical Information of China (English)

    YinHao; ZhangJiangshan

    2003-01-01

    A Robust Adaptive Video Encoder (RAVE) based on human visual model is proposed.The encoder combines the best features of Fine Granularity Scalabla (FGS) coding,frame-dropping coding,video redundancy coding,and human visual model.According to packet loss and available bandwidth of the network,the encoder adjust the output bit rate by jointly adapting quantization step-size instructed by human visual model,rate shaping,and periodically inserting key frame.The proposed encoder is implemented based on MPEG-4 encoder and is compared with the case of a conventional FGS algorithm.It is shown that RAVE is a very efficient robust videl encoder that provides improved visual quality for the receiver and consumes equal or less network resource.Results are confirmed by subjective tests and simulation tests.

  4. Recovery of human lymphocytes damaged with. gamma. -radiation or enzymatically produced oxygen radicals: different effects of poly(ADP-ribosyl)polymerase inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Marini, M.; Zunica, G. (Ist. di Istologia ed Embriologia Generale, Bologna (Italy)); Tamba, M. (Consiglio Nazionale delle Ricerche, Bologna (Italy). Lab. di Fotochimica e Radiazioni d' Alta Energia); Cossarizza, A.; Monti, D.; Franceschi, C. (Ist. di Patologia Generale, Modena (Italy))

    1990-08-01

    Quiescent human lymphocytes were damaged in two different ways, both producing toxic oxygen radicals: xanthine oxidase plus hypoxanthine (XOD/HYP), or {gamma}-rays. Under conditions where DNA synthesis was reduced to 10-20% of control, inhibitors of poly(ADP-ribosyl)polymerase (ADPRP, an enzyme that becomes activated in the presence of DNA strand breaks) allowed lymphocytes to recover completely when the damage was caused by XOD/HYP, but they did not affect DNA synthesis of irradiated cells. However, a protective effect of ADPRP inhibitors was observed with irradiated lymphocytes receiving doses {ge}50Gy. Unscheduled DNA synthesis was significantly increased when lymphocytes were damaged by high radiation doses in the presence of ADPRP inhibitors. (author).

  5. Fluorometric determination of 2'-beta-fluoro-2',3'-dideoxyadenosine 5'-triphosphate, the active metabolite of a new anti-human immunodeficiency virus drug, in human lymphocytes.

    Science.gov (United States)

    Dai, F; Kelley, J A; Zhang, H; Malinowski, N; Kavlick, M F; Lietzau, J; Welles, L; Yarchoan, R; Ford, H

    2001-01-01

    A sensitive precolumn derivatization method has been developed to measure the 5'-triphosphate of 2'-beta-fluoro-2',3'-dideoxyadenosine (F-ddA, lodenosine), a new anti-HIV drug, in human lymphocytes by HPLC using fluorescence detection. Reaction of chloroacetaldehyde with F-ddA triphosphate in extracts from human lymphocytes produces a highly fluorescent etheno adduct. This derivative is then separated and quantitated by reverse-phase paired-ion chromatography. Degradation of natural nucleic acid ribosides, such as ATP, using periodate oxidation simplifies the chromatogram and minimizes interference with detection of the target analyte. This method, modeled using cultured MOLT-4 T-lymphocytes, achieves a linear detector response for peak area measurements over the range 2.5 to 22.5 pmol (50-450 nM using 50 microl sample). Analyte recovery is greater than 90%, and the method achieves a limit of detection and limit of quantitation of 1.4 and 2.5 pmol per HPLC injection (50 microl sample containing cellular extract from 2.5 x 10(6) cells), respectively. Application of this method to measure F-ddATP in peripheral blood mononuclear cells from HIV-infected patients treated with F-ddA at 3.2 mg/kg twice daily for 22 days shows F-ddATP levels which range from 1.5 to 3.5 pmol/10(6) cells. PMID:11141306

  6. Event driven adaptation, land use and human coping strategies

    DEFF Research Database (Denmark)

    Reenberg, Anette; Birch-Thomsen, Torben; Fog, Bjarne

    and the concept of coupled human-environmental timelines. Secondly, with point of departure in a baseline characterization of Bellona Island derived from a comprehensive survey in the late 1960s and resent fieldwork in late 2006, we present the case of Bellona Island. Key issues addressed concern climatic events......The paper focuses on assessing the wider perspectives of adaptive resource management strategies in former subsistence agriculture societies in the SW Pacific. Firstly, we will briefly introduce the theoretical context related to the livelihood framework, adaptation to socio-environmental change...... of main drivers of change, incl. climatic and socio-economic changes in the recent past....

  7. Dose-response calibration curves of {sup 137}Cs gamma rays for dicentric chromosome aberrations in human lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Wol Soon; Oh, Su Jung; Jeong, Soo Kyun; Yang, Kwang Mo [Dept. of Research center, Dong Nam Institute of Radiological and Medical Sciences, Busan (Korea, Republic of); Jeong, Min Ho [Dept. of Microbiology, Dong A University College of Medicine, Busan (Korea, Republic of)

    2012-11-15

    Recently, the increased threat of radiologically industrial accident such as radiation nondestructive inspection or destruction of nuclear accident by natural disaster such as Fukushima accident requires a greater capacity for cytogenetic biodosimetry, which is critical for clinical triage of potentially thousands of radiation-exposed individuals. Dicentric chromosome aberration analysis is the conventional means of assessing radiation exposure. Dose–response calibration curves for {sup 13}'7Cs gamma rays have been established for unstable chromosome aberrations in human peripheral blood lymphocytes in many laboratories of international biodosimetry network. In this study, therefore, we established dose– response calibration curves of our laboratory for {sup 137}Cs gamma raysaccording to the IAEA protocols for conducting the dicentric chromosome assay We established in vitro dose–response calibration curves for dicentric chromosome aberrations in human lymphocytes for{sup 13}'7Cs gamma rays in the 0 to 5 Gy range, using the maximum likelihood linear-quadratic model, Y = c+αD+βD2. The estimated coefficients of the fitted curves were within the 95% confidence intervals (CIs) and the curve fitting of dose–effect relationship data indicated a good fit to the linear-quadratic model. Hence, meaningful dose estimation from unknown sample can be determined accurately by using our laboratory’s calibration curve according to standard protocol.

  8. Biochemical and molecular evidences on the protection by magnesium oxide nanoparticles of chlorpyrifos-induced apoptosis in human lymphocytes

    Directory of Open Access Journals (Sweden)

    Vida Heydary

    2015-01-01

    Full Text Available Background: Chlorpyrifos (CP is one of the most widely used organophosphate (OP insecticides in agricultural and residential pest control with its attendant adverse health effect. In the present study, it is proposed to investigate the possible modulatory role of magnesium oxide nanoparticles (MgO NPs against CP-induced toxicity in human lymphocytes and determine the mechanisms lying behind this protection by viability and biochemical assays. Materials and Methods: Isolated lymphocytes were exposed to 12 μg/mL CP either alone or in combination with different concentrations of MgO NPs (0.1 μg/mL, 1 μg/mL, 10 μg/mL, and 100 μg/mL. After a 3-day incubation, the viability and oxidative stress markers including cellular mitochondrial activity, caspase-3 and -9 activities, total antioxidant power, lipid peroxidation, and myeloperoxidase (MPO activity were measured. Also, the levels of tumor necrosis factor-α (TNF-α as inflammatory index, along with acetylcholinesterase (AChE activity were measured. Statistical differences were determined using one-way analysis of variance (ANOVA and Dunnett′s multiple comparison tests. Results: It is indicated that CP-exposed lymphocytes treated with MgO NPs resulted in a substantial reduction in the pace of mortality as well as the stages of oxidative stress in a dose-dependent manner. Also, MgO NPs (100 μg/mL meaningfully restored CP-induced increase of TNF-α (P < 0.001 and decrease of AChE activity (P < 0.001 and were capable of preventing CP-treated human lymphocytes from apoptosis (P < 0.001. Conclusion: Our results demonstrate that MgO NPs in approximate 100 nm diameter not only make cells resistant to the toxic properties of CP but also attenuate toxic effects of CP, which is demonstrating the potential of MgO NPs to be applied in future immune deficiency therapeutic strategies.

  9. Alpharetroviral self-inactivating vectors produced by a superinfection-resistant stable packaging cell line allow genetic modification of primary human T lymphocytes.

    Science.gov (United States)

    Labenski, Verena; Suerth, Julia D; Barczak, Elke; Heckl, Dirk; Levy, Camille; Bernadin, Ornellie; Charpentier, Emmanuelle; Williams, David A; Fehse, Boris; Verhoeyen, Els; Schambach, Axel

    2016-08-01

    Primary human T lymphocytes represent an important cell population for adoptive immunotherapies, including chimeric-antigen and T-cell receptor applications, as they have the capability to eliminate non-self, virus-infected and tumor cells. Given the increasing numbers of clinical immunotherapy applications, the development of an optimal vector platform for genetic T lymphocyte engineering, which allows cost-effective high-quality vector productions, remains a critical goal. Alpharetroviral self-inactivating vectors (ARV) have several advantages compared to other vector platforms, including a more random genomic integration pattern and reduced likelihood for inducing aberrant splicing of integrated proviruses. We developed an ARV platform for the transduction of primary human T lymphocytes. We demonstrated functional transgene transfer using the clinically relevant herpes-simplex-virus thymidine kinase variant TK.007. Proof-of-concept of alpharetroviral-mediated T-lymphocyte engineering was shown in vitro and in a humanized transplantation model in vivo. Furthermore, we established a stable, human alpharetroviral packaging cell line in which we deleted the entry receptor (SLC1A5) for RD114/TR-pseudotyped ARVs to prevent superinfection and enhance genomic integrity of the packaging cell line and viral particles. We showed that superinfection can be entirely prevented, while maintaining high recombinant virus titers. Taken together, this resulted in an improved production platform representing an economic strategy for translating the promising features of ARVs for therapeutic T-lymphocyte engineering. PMID:27162078

  10. An in vitro study of liposomal curcumin: stability, toxicity and biological activity in human lymphocytes and Epstein-Barr virus-transformed human B-cells.

    Science.gov (United States)

    Chen, Changguo; Johnston, Thomas D; Jeon, Hoonbae; Gedaly, Roberto; McHugh, Patrick P; Burke, Thomas G; Ranjan, Dinesh

    2009-01-21

    Curcumin is a multi-functional and pharmacologically safe natural agent. Used as a food additive for centuries, it also has anti-inflammatory, anti-virus and anti-tumor properties. We previously found that it is a potent inhibitor of cyclosporin A (CsA)-resistant T-cell co-stimulation pathway. It inhibits mitogen-stimulated lymphocyte proliferation, NFkappaB activation and IL-2 signaling. In spite of its safety and efficacy, the in vivo bioavailability of curcumin is poor, and this may be a major obstacle to its utility as a therapeutic agent. Liposomes are known to be excellent carriers for drug delivery. In this in vitro study, we report the effects of different liposome formulations on curcumin stability in phosphate buffered saline (PBS), human blood, plasma and culture medium RPMI-1640+10% FBS (pH 7.4, 37 degrees C). Liposomal curcumin had higher stability than free curcumin in PBS. Liposomal and free curcumin had similar stability in human blood, plasma and RPMI-1640+10% FBS. We looked at the toxicity of non-drug-containing liposomes on (3)H-thymidine incorporation by concanavalin A (Con A)-stimulated human lymphocytes, splenocytes and Epstein-Barr virus (EBV)-transformed human B-cell lymphoblastoid cell line (LCL). We found that dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylglycerol (DMPG) were toxic to the tested cells. However, addition of cholesterol to the lipids at DMPC:DMPG:cholesterol=7:1:8 (molar ratio) almost completely eliminated the lipid toxicity to these cells. Liposomal curcumin had similar or even stronger inhibitory effects on Con A-stimulated human lymphocyte, splenocyte and LCL proliferation. We conclude that liposomal curcumin may be useful for intravenous administration to improve the bioavailability and efficacy, facilitating in vivo studies that could ultimately lead to clinical application of curcumin.

  11. An in vitro study of liposomal curcumin: stability, toxicity and biological activity in human lymphocytes and Epstein-Barr virus-transformed human B-cells.

    Science.gov (United States)

    Chen, Changguo; Johnston, Thomas D; Jeon, Hoonbae; Gedaly, Roberto; McHugh, Patrick P; Burke, Thomas G; Ranjan, Dinesh

    2009-01-21

    Curcumin is a multi-functional and pharmacologically safe natural agent. Used as a food additive for centuries, it also has anti-inflammatory, anti-virus and anti-tumor properties. We previously found that it is a potent inhibitor of cyclosporin A (CsA)-resistant T-cell co-stimulation pathway. It inhibits mitogen-stimulated lymphocyte proliferation, NFkappaB activation and IL-2 signaling. In spite of its safety and efficacy, the in vivo bioavailability of curcumin is poor, and this may be a major obstacle to its utility as a therapeutic agent. Liposomes are known to be excellent carriers for drug delivery. In this in vitro study, we report the effects of different liposome formulations on curcumin stability in phosphate buffered saline (PBS), human blood, plasma and culture medium RPMI-1640+10% FBS (pH 7.4, 37 degrees C). Liposomal curcumin had higher stability than free curcumin in PBS. Liposomal and free curcumin had similar stability in human blood, plasma and RPMI-1640+10% FBS. We looked at the toxicity of non-drug-containing liposomes on (3)H-thymidine incorporation by concanavalin A (Con A)-stimulated human lymphocytes, splenocytes and Epstein-Barr virus (EBV)-transformed human B-cell lymphoblastoid cell line (LCL). We found that dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylglycerol (DMPG) were toxic to the tested cells. However, addition of cholesterol to the lipids at DMPC:DMPG:cholesterol=7:1:8 (molar ratio) almost completely eliminated the lipid toxicity to these cells. Liposomal curcumin had similar or even stronger inhibitory effects on Con A-stimulated human lymphocyte, splenocyte and LCL proliferation. We conclude that liposomal curcumin may be useful for intravenous administration to improve the bioavailability and efficacy, facilitating in vivo studies that could ultimately lead to clinical application of curcumin. PMID:18840516

  12. Regulation of DNA synthesis and the cell cycle in human prostate cancer cells and lymphocytes by ovine uterine serpin

    Directory of Open Access Journals (Sweden)

    Hansen Peter J

    2008-01-01

    Full Text Available Abstract Background Uterine serpins are members of the serine proteinase inhibitor superfamily. Like some other serpins, these proteins do not appear to be functional proteinase inhibitors. The most studied member of the group, ovine uterine serpin (OvUS, inhibits proliferation of several cell types including activated lymphocytes, bovine preimplantation embryos, and cell lines for lymphoma, canine primary osteosarcoma and human prostate cancer (PC-3 cells. The goal for the present study was to evaluate the mechanism by which OvUS inhibits cell proliferation. In particular, it was tested whether inhibition of DNA synthesis in PC-3 cells involves cytotoxic actions of OvUS or the induction of apoptosis. The effect of OvUS in the production of the autocrine and angiogenic cytokine interleukin (IL-8 by PC-3 cells was also determined. Finally, it was tested whether OvUS blocks specific steps in the cell cycle using both PC-3 cells and lymphocytes. Results Recombinant OvUS blocked proliferation of PC-3 cells at concentrations as low as 8 μg/ml as determined by measurements of [3H]thymidine incorporation or ATP content per well. Treatment of PC-3 cells with OvUS did not cause cytotoxicity or apoptosis or alter interleukin-8 secretion into medium. Results from flow cytometry experiments showed that OvUS blocked the entry of PC-3 cells into S phase and the exit from G2/M phase. In addition, OvUS blocked entry of lymphocytes into S phase following activation of proliferation with phytohemagglutinin. Conclusion Results indicate that OvUS acts to block cell proliferation through disruption of the cell cycle dynamics rather than induction of cytotoxicity or apoptosis. The finding that OvUS can regulate cell proliferation makes this one of only a few serpins that function to inhibit cell growth.

  13. Modulation of gamma ray induced chromosome aberrations in human peripheral blood lymphocytes by Hippophae rhammnoides leaf extract, SBL-1

    International Nuclear Information System (INIS)

    Hippophae rhammnoides L. commonly known as seabuckthorn is a temperate shrub and native of Asia and Europe. It has high antioxidant potential and is known to the traditional Indian, Chinese and Tibetan medicinal system for treatment of multiple disorders viz., circulatory and digestive disorders, hepatic injuries, neoplasia etc. One time treatment with the standardized leaf extract from H. rhammnoides (SBL-1) before whole body irradiation with 60Co (10 Gy), rendered more than 90% survival in non SBL-1 treated irradiated animals (J herbs, spices medi plants, 2009). Present study investigated the effects of SBL-1 treatment on chromosomal damage in human peripheral blood lymphocytes (PBL), with or without 60Co-gamma-radiation. The lymphocytes were isolated from the blood drawn from different donors. The isolated lymphocytes were divided into several groups: Group 1-untreated control, Group 2-irradiated (2 Gy), Group 3, 4 and 5 were treated with different concentration of SBL-1, 30 min. after irradiation with 60Co-gamma-rays (2 Gy). Group 6 was treated with the maximum concentration of SBL-1 used in the study. The metaphase spreading technique was used as per standard procedure to record chromosome breaks, dicentrics, acentrics and rings. The results were also recorded in terms of total aberrant metaphase and frequency of aberrant metaphase per 100 cells. In comparison to the untreated control, in the irradiated PBL culture, there was 8-fold increase in breaks, 211-folds in dicentrics, 75-folds in acentrics and 3-folds in rings (average data). SBL-1 alone at the highest concentration did not cause any significant change in number of breaks, dicentrics, acentrics and rings. The radiation induced aberrations decreased significantly by treatment with SBL-1 and the maximum decrease was observed when the cells were treated with 22μg/ml of SBL-1. These results demonstrated the anti-clastogenic activity of SBL-1 against gamma radiation induced damage. (author)

  14. Activation of human T lymphocytes by Leishmania lipophosphoglycan

    DEFF Research Database (Denmark)

    Kemp, M; Theander, T G; Handman, E;

    1991-01-01

    This study describes Leishmania antigen-induced activation of lymphocytes isolated from Kenyan donors, previously treated for visceral leishmaniasis, and from Danish and Kenyan controls. Peripheral blood mononuclear cells (PBMC) from cured Kala-Azar patients proliferated and produced Interferon...... 63 failed to activate PBMC from any of the donors tested. These results show that the individuals cured from visceral leishmaniasis had expanded T-cell clones recognizing LPG, conceivably as a result of Leishmania infection. The LPG preparation was without detectable protein contamination. Thus...

  15. Interleukin 1-induced down-regulation of antibody binding to CD4 molecules on human lymphocytes

    DEFF Research Database (Denmark)

    Tvede, N; Christensen, L D; Ødum, Niels;

    1988-01-01

    Interleukin 1 (IL-1) is involved in the early activation of T lymphocytes. The CD4 antigen, described as a phenotypic marker of helper T cells, is also important in early T-cell activation by its ability to bind to MHC class II molecules on antigen-presenting cells, and to transmit positive (and......+ cells. Under optimal growth conditions, the initial reduction in antibody binding to CD4 was followed by an apparent re-expression of the CD4 antigen even in the presence of high concentrations of IL-1. This re-expression did not occur if the cells were cultured at 4 degrees C, or after treatment...

  16. Modelling Adaptive Learning Behaviours for Consensus Formation in Human Societies

    Science.gov (United States)

    Yu, Chao; Tan, Guozhen; Lv, Hongtao; Wang, Zhen; Meng, Jun; Hao, Jianye; Ren, Fenghui

    2016-06-01

    Learning is an important capability of humans and plays a vital role in human society for forming beliefs and opinions. In this paper, we investigate how learning affects the dynamics of opinion formation in social networks. A novel learning model is proposed, in which agents can dynamically adapt their learning behaviours in order to facilitate the formation of consensus among them, and thus establish a consistent social norm in the whole population more efficiently. In the model, agents adapt their opinions through trail-and-error interactions with others. By exploiting historical interaction experience, a guiding opinion, which is considered to be the most successful opinion in the neighbourhood, can be generated based on the principle of evolutionary game theory. Then, depending on the consistency between its own opinion and the guiding opinion, a focal agent can realize whether its opinion complies with the social norm (i.e., the majority opinion that has been adopted) in the population, and adapt its behaviours accordingly. The highlight of the model lies in that it captures the essential features of people’s adaptive learning behaviours during the evolution and formation of opinions. Experimental results show that the proposed model can facilitate the formation of consensus among agents, and some critical factors such as size of opinion space and network topology can have significant influences on opinion dynamics.

  17. Lymphocyte Trafficking to Mucosal Tissues

    DEFF Research Database (Denmark)

    Mikhak, Zamaneh; Agace, William Winston; Luster, Andrew D.

    2015-01-01

    Lymphocytes are the key cells of the adaptive immune system that provide antigen-specific responses tailored to the context of antigen exposure. Through cytokine release and antibody production, lymphocytes orchestrate and amplify the recruitment and function of other immune cells and contribute to...... host defense against invading pathogens and the pathogenesis of many inflammatory diseases. Lymphocyte function is critically dependent on their ability to traffic into the correct anatomic locations at the appropriate times. This process is highly regulated and requires that lymphocytes interact with...

  18. Binding, uptake and degradation of human recombinant interleukin-2 (125 ala) in activated human T- and B-lymphocytes and in monocytemacrophages

    International Nuclear Information System (INIS)

    High-affinity receptors for IL-2 (ala 125) were demonstrated in PHA-, antigen- and/or alloantigen-activated human T-cells (both proliferative and cytotoxic), in PWM-activated human B-cells and in human monocyte-macrophages. Binding in PHA-blasts was irreversible and Ca++-independent, and labelled IL-2 (ala 125) bound at 4 deg. C could not be removed by trypsin treatment. Binding was strongly pH-dependent, and lowering of pH caused release of nearly all cell associated radioactivity at 4 deg. C. In T- and B-lymphocytes, additional binding at high ligand concentrations was accounted for by receptors of much lower affinity. Binding to low-affinity receptors appeared reversible. At 4 deg. C, 2.2 pM labelled IL-2 (ala 125) bound to PHA-blasts (3.6 x 106/ml) with a half time of about 15 min, and the association rate constant was approximately 8 x 109 M-1 min -1. The number of high affinity receptors per T-cell was determined as 9.7 ± 0.5 x 102. At 37 deg. C, 60% of the tracer bound at 4 deg. C was rapidly internalized (Kint = 0.89 x 10-1 min-1), and radioactivity comprising small MW products and iodotyrosine was released following a sigmoidal curve after a 20 min lag period. Similar results were obtained in PWM-activated B-lymphocytes and in cultured monocytes. It is concluded that high-affinity receptors mediate binding, uptake and degradation of IL-2 in activated human T- and B-lymphocytes and in monocyte-macrophages. (author)

  19. The origins of music as an adaptive trait in humans

    OpenAIRE

    Amodeo, Martín Raúl

    2014-01-01

    Throughout human history, people have developed the faculty to appreciate and create music. Musical thinking implies the development of cognitive and emotional faculties by complex neural processes. How could such a complex behavior as music be originated by evolution? This article reviews the main evolutionary approaches that have been proposed to explain this process. The main hypotheses state that music has emerged from adaptive processes such as communication and emotional coordination be...

  20. Influence of occupational exposure to pesticides on the level of DNA damage induced in human lymphocytes (Polish group) by UV-C and X-rays

    International Nuclear Information System (INIS)

    The aim of this study was to find out whether occupational exposure to pesticides might affect the individual susceptibility of various donors to the induction of DNA damage by genotoxic agents (UV-C, X-rays) and the efficiency of cellular repair. Previously cryo preserved lymphocytes were defrosted, and DNA damage in the lymphocytes prior to any in vitro studies was investigated with the application of the Comet assay. In order to evaluate the susceptibilities of human lymphocytes to genotoxic agents and the variability of repair capacities, the DNA migrations were estimated immediately after exposure to UV-C light or X-rays and after two hours. On average, the DNA damage detected in untreated lymphocytes was significantly higher in the group exposed to pesticides than in reference group. UV-C treated lymphocytes from group exposed to pesticides shows a greater statistically significant level of DNA migration compared to the reference group, detected after 2 hours incubation in the absence of PHA. Significantly lower responses to X-rays and higher levels of residual DNA damage were detected in the lymphocytes of donors from the group exposed to pesticides compared with the reference group. In conclusion, our results suggest that occupational exposure to pesticides influences the level of induced DNA damage, and the cellular capabilities of repair. (author)

  1. Comparison of transformation, DNA single strand breaks and its repair in human blood lymphocytes stimulated with PHA, ConA and PWM following exposure to γ-rays

    International Nuclear Information System (INIS)

    The transformation, DNA single strand breaks and its repair in human peripheral blood lymphocytes stimulated with PHA, ConA and PWM respectively following exposure to 60Co γ-rays were analyzed by 3H-thymidine incorporation and hydroxylapatite chromatography. The transformation of lymphocytes stimulated with PHA, ConA and PWM were suppressed by γ-rays and the dose-effect curves were biphasic within the range of 0-8 Gy. The lymphocytes stimulated with PWM were the most resistant to γ-rays. The extent of DNA single strand breaks in lymphocytes induced by γ-rays was linearly related to the dose within the range of 0-30 Gy and there was no marked difference in the three kinds of lymphocytes. After a period of post-irradiation (15 Gy) incubation at 37 deg C, the DNA single strand breaks could be rejoined but incompletely. The rejoined strands broke again if the cells were incubated longer. The repair ratio of single strand breaks in the lymphocytes stimulated with PWM was the highest among the cells with three mitogens. The results suggest that the difference of the radiation effect on transformation in different lytphocytes is probably related to the repair ability of DNA single strand breaks

  2. Evaluation of antigenotoxic effects of carotenoids from green algae Chlorococcum humicola using human lymphocytes

    Institute of Scientific and Technical Information of China (English)

    Bhagavathy S; Sumathi P

    2012-01-01

    Objective:To identify the available phytochemicals and carotenoids in the selected green algae and evaluate the potential genotoxic/antigenotoxic effect using lymphocytes. Methods:Organic solvent extracts of Chlorococcum humicola (C. humicola) were used for the phytochemical analysis. The available carotenoids were assessed by HPLC, and LC-MS analysis. The genotoxicity was induced by the benzo(a)pyrene in the lymphocyte culture, the genotoxic and antigenotoxic effects of algal carotenoids with and without genotoxic inducer were evaluated by chromosomal aberration (CA), sister chromatid exchange (SCE) and micronucleus assay (MN). Results: The results of the analysis showed that the algae were rich in carotenoids and fatty acids. In the total carotenoids lutein,β-carotene and α-carotene were found to be present in higher concentration. The frequency of CA and SCE increased by benzo(a)pyrene were significantly decreased by the carotenoids (P<0.05 for CA, P<0.001 for SCE). The MN frequencies of the cells were significantly decreased by the treatment with carotenoids when compared with the positive controls (P<0.05). Conclusions:The findings of the present study demonstrate that, the green algae C. humicola is a rich source of bioactive compounds especially carotenoids which effectively fight against environmental genotoxic agents, the carotenoids itself is not a genotoxic substance and should be further considered for its beneficial effects.

  3. Cytogenetic study of Ascaris trypsin inhibitor in cultured human lymphocytes with metabolic activation

    Indian Academy of Sciences (India)

    Joanna Blaszkowska; Wanda Bratkowska; Dobroslawa Lopaczynska; Tomasz Ferenc

    2009-04-01

    The trypsin inhibitor (ATI) isolated from gastrointestinal nematode Ascaris suum was tested in vitro for induction of chromosome aberrations and sister chromatid exchanges (SCE). Genotoxicity assessment of purified ATI was carried out on metaphase plates received from peripheral blood lymphocyte macroculture (48 h test of structural chromosome aberrations and 72 h test of SCE) with exogenous metabolic activation. ATI was tested in dose of 25, 50 and 100 μg per ml of culture. Kinetics of cell divisions were determined by the replication index (RI). The mitotic index (MI) was expressed as a number of metaphases per 1000 nuclei analysed. Analysis of chromosome aberrations showed that higher doses of ATI (50 and 100 /ml) significantly increased the frequency of chromosome aberrations (mainly of chromatid gaps and breaks) compared to the negative control. All concentrations of ATI caused a statistically significant reduction in the MI and RI. In comparison with the negative control, a significant increase in the SCE frequency was observed in all applied doses of ATI. Thus, in the presence of S9 activation, the Ascaris trypsin inhibitor showed potential clastogenic activity and inhibition of the dynamics of lymphocyte divisions.

  4. IL-17-Expressing CD4+ and CD8+ T Lymphocytes in Human Toxoplasmosis

    Directory of Open Access Journals (Sweden)

    Jéssica Líver Alves Silva

    2014-01-01

    Full Text Available This study aimed to measure the synthesis of Th1 and Th2 cytokines by mononuclear cells after culture with live T. gondii and identified Th17 (CD4+ and Tc17 (CD8+ cells in toxoplasma-seronegative and toxoplasma-seropositive parturient and nonpregnant women. Cytometric bead arrays were used to measure cytokine levels (IL-2, TNF-α, IFN-γ, IL-4, IL-5, and IL-10; immunophenotyping was used to characterize Th17 and Tc17 cells, and the cells were stained with antibodies against CD4+ and CD8+ T cells expressing IL-17. The addition of tachyzoites to cell cultures induced the synthesis of IL-5, IL-10, and TNF-α by cells from seronegative parturient women and of IL-5 and IL-10 by cells from seropositive, nonpregnant women. We observed a lower level of IL-17-expressing CD4+ and CD8+ T lymphocytes in cultures of cells from seronegative and seropositive parturient and nonpregnant women that were stimulated with tachyzoites, whereas analysis of the CD4+ and CD8+ T cell populations showed a higher level of CD4+ T cells compared with CD8+ T cells. These results suggest that the cytokine pattern and IL-17-expressing CD4+ and CD8+ T lymphocytes may have important roles in the inflammatory response to T. gondii, thus contributing to the maintenance of pregnancy and control of parasite invasion and replication.

  5. Investigating chromosome damage and gammaH2AX response in human lymphocytes and lymphocyte subsets as potential biomarkers of radiation sensitivity

    Science.gov (United States)

    Beaton, Lindsay A.

    This thesis examines in vitro irradiated blood samples from prostate cancer patients exhibiting late normal tissue damage after receiving radiotherapy, for lymphocyte response. Chromosomal aberrations, translocations and proliferation rate are measured, as well as gammaH2AX response in lymphocytes and lymphocyte subsets. The goal of this thesis is to determine whether the lymphocyte response to in vitro radiation could be used as a marker for radiosensitivity. Patients were selected from a randomized clinical trial evaluating the optimal timing of Dose Escalated Radiation and short course Androgen Deprivation Therapy. Of 438 patients, 3% developed Grade 3 late radiation proctitis and were considered to be radiosensitive. Blood was drawn from 10 of these patients along with 20 matched samples from patients with grade 0 proctitis. The samples were irradiated and were analyzed for dicentric chromosomes, excess fragments and proliferation rates (at 6 Gy), translocations, stable and unstable damage (at 4 Gy), and dose response (up to 10 Gy), along with time response after 2 Gy (0 -- 24 h). Chromosome aberrations, excess fragments per cell, translocations per cell and proliferation rates were analyzed by brightfield and fluorescent microscopy, while the gammaH2AX response in lymphocytes and lymphocyte subsets was analyzed by flow cytometry. Both groups were statistically similar for all endpoints at 0 Gy. At 6 Gy, there were statistically significant differences between the radiosensitive and control cohorts for three endpoints; the mean number of dicentric chromosomes per cell, the mean number of excess fragments per cell and the proportion of cells in second metaphase. At 4 Gy, there were statistically significant differences between the two cohorts for three endpoints; the mean number of translocations per cell, the mean number of dicentric chromosomes per cell and the mean number of deletions per cell. There were no significant differences between the gammaH2AX

  6. Assessment of individual radiosensitivity in human lymphocytes of cancer patients and its correlation with adverse side effects to radiation therapy

    International Nuclear Information System (INIS)

    Background and purpose: Individual radiosensitivity is an inherent characteristic, associated with an increased reaction to ionizing radiation on the human body. Biological endpoints such as clonogenic survival, chromosome aberration formation and repair capacity of radiation-induced damage have been applied to evaluate individual radiosensitivity in vitro. 5%-7% of cancer patients develop adverse side effects to radiation therapy in normal tissues within the treatment field, which are referred as 'clinical radiation reactions' and include acute effects, late effects and cancer induction. It has been hypothesized that the occurrence and severity of these reactions are mainly influenced by genetic susceptibility to radiation. Additionally, the nature of the genetic disorders associated with hypersensitivity to radiotherapy suggests that DNA repair mechanisms are involved. Consequently, the characterization of DNA repair in lymphocytes through cytokinesis blocked micronucleus (MN) and alkaline single-cell micro gel electrophoresis (comet) assays could be suitable approaches to evaluate individual radiosensitivity in vitro. The MN assay is an established cytogenetic technique to evaluate intrinsic cell radiosensitivity in tumor cells and lymphocytes; comet assay is a sensitive and rapid method for measuring DNA damage and repair in individual cells. The aims of this study were: 1) To assess the in vitro radiosensitivity of peripheral blood lymphocytes from two groups of cancer patients (retrospectively and prospectively studied), using MN and comet assays, in comparison with the observed clinical response; and 2) To test the predictive potential of both techniques. Materials and methods: 38 cancer patients receiving radiation therapy were enrolled in this study. The tumor sites were: head and neck (n 25) and cervix (n = 13). Nineteen patients were evaluated about 6-18 month after radiotherapy (retrospective group) and 19 patients were evaluated prior, mid-way and on

  7. In vitro assessment of genotoxic effects of electric arc furnace dust on human lymphocytes using the alkaline comet assay.

    Science.gov (United States)

    Garaj-Vrhovac, Vera; Orescanin, Visnja; Ruk, Damir; Gajski, Goran

    2009-02-15

    In vitro genotoxic effects of leachates of electric arc furnace dust (EAFD) on human peripheral lymphocytes, assessed prior and following the treatment with a strong alkaline solution were investigated using the alkaline comet assay. Prior and following the treatment, lymphocytes were incubated with leachate of EAFD for 6 and 24 hours at 37 degrees C. Negative controls were also included. Mean values of the tail lengths established in the samples treated with the leachate stemming from the original dust for 6 and 24 hours, were 15.70 microm and 16.78 microm, respectively, as compared to 12.33 microm found in the control sample. Slight, but significant increase in the tail length was also found with the dust treated with a strong alkaline solution (13.37 microm and 13.60 microm). In case of high heavy metal concentrations (the extract of the original furnace dust), the incubation period was revealed to be of significance as well. The obtained results lead to the conclusion that alkaline comet assay could be used as a rapid, sensitive and low-cost tool when assessing genotoxicity of various waste materials, such as leachates of the electric arc furnace dust.

  8. Genotoxic and cytotoxic effects of iron sulfate in cultured human lymphocytes treated in different phases of cell cycle.

    Science.gov (United States)

    Lima, P D L; Vasconcellos, M C; Montenegro, R A; Sombra, C M L; Bahia, M O; Costa-Lotufo, L V; Pessoa, C O; Moraes, M O; Burbano, R R

    2008-04-01

    Iron (Fe) is a common chemical element that is essential for organisms as a co-factor in oxygen transport, but that in high amounts presents a significant risk of neurodegenerative disorders. The objective of this study was to evaluate the mutagenic potential of iron sulfate. The comet assay and chromosome aberration (CA) analysis were applied to determine the DNA-damaging and clastogenic effects of iron sulfate. Human lymphocytes were treated in the quiescent phase for the comet assay and proliferative phase during the G1, G1/S, S (pulses of 1 and 6 h), and G2 phases of the cell cycle for CA analysis, with 1.25, 2.5 and 5 microg/mL concentrations of FeSO(4).7H2O. All tested concentrations were cytotoxic and reduced significantly the mitotic index (MI) in all phases of the cell cycle. They also induced CA in G1, G1/S and S (pulses of 1 and 6 h) phases. Iron sulfate also induced polyploidy in cells treated during G1. In the comet assay, this metal did not induce significant DNA damage. Our results show that Fe causes alteration and inhibition of DNA synthesis only in proliferative cells, which explain the concomitant occurrence of mutagenicity and cytotoxicity, respectively, in the lymphocytes studied.

  9. The use of the differential staining of sister chromatids in the study of the cytogenetic radiation effects in human lymphocytes

    International Nuclear Information System (INIS)

    Differential staining of sister chromatides is performed, cells of the 1-st and the following mitoses are identified, chromosome aberrations are accounted, and statistic processing of data is performed. Venous blood of healthy donors is used as material for analysis. It is irradiated in flasks by 60Co gamma-quanta in the doses of 1, 1.5, 2, 3, 4, 5, 6, and 8 Gy. Lymphocytes of the peripheral blood are cultivated at 37 deg C in the medium containing antibiotics, phytohemaggluninin and 5-bromiurnedeoxyidine (BDU). The observed distributions of dicentrics in cells are compared with theoretic Poisson distribution. The dependence of frequency of dicentrics on radiation dose is studied by the method of regressive analysis. The importance of applying this technique in radiation cytogenetic investigations to increase the accuracy of chromosome aberration account in stimulated phytohemagglutinin cultures of lymphocytes of human peripheral blood and to study regularities of their elimination after cells pass the 1-st and the second mitoses, is shown

  10. Subpopulations of lymphocytes and their bearing on the radiation dose-response of the human lymphocyte (cell survival, mitogenic stimulation and chromosome aberration frequency)

    International Nuclear Information System (INIS)

    To determine whether in the lymphocyte the frequency of chromosome aberrations might be influenced by a differential radiation response of the varying types of cells, as well as interactions among them, subpopulations were separated on the basis of differences in cell surface receptors. The subpopulations, namely, T and B lymphocytes and three T subsets, T-M, T-G, T-null, were found to differ in radiosensitivity as measured by survival in culture and mitotic index after PHA stimulation. All the populations studied are represented to varying degrees among the mitotic cells of unirradiated samples 48 hours after PHA stimulation. At increasing doses of 6Co gamma rays (50, 100, 250, 500 rads), however, their proportions change both as a direct result of irradiation, such as cell killing, and as an indirect effect, such as the reduction in suppressor cell action

  11. [Potency determination of horse anti-human-lymphocyte serum (ALS) by means of the lymphocyte resistance test, a modification of Schroder's leukocyte resistance test].

    Science.gov (United States)

    Mundt, B; Preussner, S; Frick, G; Bast, G

    1975-01-01

    The leukocyte resistance test of Schröder was used for the purpose of modifying the in vitro determination of cytotoxic potency of ALS during the course of immunization. In contrast to the original method, where the test was carried out with whole blood, the incubation was made with pure lymphocyte cell suspensions. The results obtained show that the extensive procedure of examination enables the cytotoxic effectiveness of antilymphocytic antibodies to be evaluated. PMID:54295

  12. Cytogenetic investigation of contrast media effects in human peripheral blood lymphocytes

    International Nuclear Information System (INIS)

    The aim of present investigation is to detect the cytogenetic effect in peripheral blood lymphocytes of patients subjected to radiodiagnostic examination with contrast media. Material and method: The investigation was performed on 17 patients subjected to radio diagnostic examinations with different kinds of contrast media.The skin dose obtained by diagnostic x-ray exposure is measured by thermoluminescence dosimetry. Cytogenetic analyses are performed before, as well as immediately after the examination. Chromosomal aberrations are used as a bio marker for cytogenetic effects analysis. Results show an increase of mean level of chromosomal damage after the radio diagnostic examination in comparison to the mean level before exposure. This increase is statistically significant. Further work on the investigation of cytogenetic effects of diagnostic dose x-rays and contrast media used in invasive radiological examinations is in progress. (authors)

  13. DNA damage in subpopulations of human lymphocytes irradiated with doses in the range of 0-1 Gy of X-radiation

    International Nuclear Information System (INIS)

    We compared three methods usually applied in biological dosimetry for estimation of radiation-induced DNA damage in human T and B lymphocytes: alkaline comet assay, micronucleus (MN) test and formation of histone gamma-H2AX foci. Human peripheral blood lymphocytes were fractionated using T cells and B cells isolation kits. Cells were irradiated with doses in the range of 0-1 Gy of X-rays. Induction of DNA damage was assessed by the standard alkaline comet assay, MN test and histone gamma-H2AX foci immunofluorescence assay. Notwithstanding different end-points measured by the applied methods, all tests revealed a similar induction of DNA damage in B lymphocytes as compared with T lymphocytes. The results indicated that all three tests detect DNA damage with similar sensitivity, the lowest dose being approximately 0.3 Gy. The difference between irradiated and control cells was expressed as the ratio of the value obtained for irradiated cells (1 Gy) to that for control cells. The highest ratio was obtained for formation of gamma-H2AX foci and was 6.2 for T and 13.8 for B lymphocytes, whereas those for comet assay and micronucleus test were 3.5; 3.6 and 5.6; 4.8, respectively. (authors)

  14. Histological analysis of gamma delta T lymphocytes infiltrating human triple-negative breast carcinomas

    Directory of Open Access Journals (Sweden)

    Jose Villacorta Hidalgo

    2014-12-01

    Full Text Available Breast cancer is the leading cause of cancer death in women and the second most common cancer worldwide after lung cancer. The remarkable heterogeneity of breast cancers influences numerous diagnostic, therapeutic and prognostic factors. Triple-negative breast cancers (TNBCs lack expression of HER2 and the estrogen and progesterone receptors and often contain lymphocytic infiltrates. Most of TNBCs are invasive ductal carcinomas (IDCs with poor prognosis, whereas prognostically more favorable subtypes such as medullary breast carcinomas (MBCs are somewhat less frequent. Infiltrating T cells have been associated with an improved clinical outcome in TNBCs. The prognostic role of γδ T cells within CD3+ tumor-infiltrating T lymphocytes remains unclear. We analyzed 26 TNBCs, 14 IDCs and 12 MBCs, using immunohistochemistry for the quantity and patterns of γδ T-cell infitrates within the tumor microenvironment. In both types of TNBCs, we found higher numbers of γδ T cells in comparison with normal breast tissues and fibroadenomas. The numbers of infiltrating γδ T cells were higher in MBCs than in IDCs. γδ T cells in MBCs were frequently located in direct contact with tumor cells, within the tumor and at its invasive border. In contrast, most γδ T cells in IDCs were found in clusters within the tumor stroma. These findings could be associated with the fact that the patient’s prognosis in MBCs is better than that in IDCs. Further studies to characterize these γδ T cells at the molecular and functional level are in progress.

  15. Chromosome breakage in lymphocytes from humans with body burdens of 226Ra

    International Nuclear Information System (INIS)

    Peripheral lymphocytes from 10 controls and 40 patients with body burdens of 226Ra ranging from below the limit of detection to 8.6 μCi were scored for unstable chromosome aberrations. The patient population was divided into four groups: a group with body burdens below the limit of detection (less than 0.003 μCi, 12 patients); a low-burden group (0.003 to 0.099 μCi, 13 patients); a moderate-burden group (0.1 to 0.99 μCi, 11 patients); and a high-burden group (greater than 1.0 μCi, 4 patients). In none of these groups was the frequency of cells with unstable aberrations significantly elevated above that in the controls. The rate of occurrence of dicentric and ring chromosomes was above the control frequency in only the two patients with the highest burdens (3.55 and 8.6 μCi). Our results are consistent with the expectation derived from a recent calculation of alpha dose delivered to blood by bone-deposited radium and its decay products. Marshall and Hoegerman have estimated that the blood dose for an individual with a radium burden of 1.0 μCi is 0.09 +- 0.03 rad/year. The value is compared with the dose estimate used by Boyd et al. in their study of British radium-dial painters, and the relevance of the blood dose to the lymphocyte dose is discussed

  16. 1,2:3,4-Diepoxybutane Induces Multipolar Mitosis in Cultured Human Lymphocytes.

    Science.gov (United States)

    Barajas Torres, Reyna Lucía; Domínguez Cruz, Martín Daniel; Borjas Gutiérrez, César; Ramírez Dueñas, María de Lourdes; Magaña Torres, María Teresa; González García, Juan Ramón

    2016-01-01

    1,3-Butadiene, a colorless gas regularly used in the production of plastics, thermoplastic resins, and styrene-butadiene rubber, poses an increased leukemia mortality risk to workers in this field. 1,3-Butadiene is also produced by incomplete combustion of motor fuels or by tobacco smoking. It is absorbed principally through the respiratory system and metabolized by several enzymes rendering 1,2:3,4-diepoxybutane (DEB), which has the highest genotoxic potency of all metabolites of 1,3-butadiene. DEB is considered a carcinogen mainly due to its high potential as clastogen, which induces structural chromosome aberrations such as sister chromatid exchanges, chromosomal breaks, and micronuclei. Due to its clastogenic effect, DEB is one of the most used agents for diagnostic studies of Fanconi anemia, a recessively inherited disease related to mutations affecting several genes involved in a common DNA repair pathway. When performing Fanconi anemia diagnostic tests in our laboratory, we have observed occasional multipolar mitosis (MM) in lymphocyte cultures exposed to 0.1 μg/ml of DEB and harvested in the absence of any mitotic spindle inhibitor. Although previous studies reported an aneugenic effect (i.e. it induces aneuploidy) of DEB, no mechanism was suggested to explain such observations. Therefore, the aim of this study was to investigate whether exposure to 0.1 μg/ml of DEB is significantly associated with the occurrence of MM. We blindly assessed the frequency of MM in lymphocyte cultures from 10 nonsmoking healthy individuals. Two series of 3 cultures were performed from each sample under different conditions: A, without DEB; B, with 0.1 μg/ml of DEB, and C, with 25 μM of mitomycin C as positive control. Cultures exposed to DEB showed higher frequencies of MM (23 of 2,000 cells) than did the unexposed ones (3 of 2,000 cells). PMID:27193269

  17. Extended interferon-alpha therapy accelerates telomere length loss in human peripheral blood T lymphocytes.

    Directory of Open Access Journals (Sweden)

    Joel M O'Bryan

    Full Text Available BACKGROUND: Type I interferons have pleiotropic effects on host cells, including inhibiting telomerase in lymphocytes and antiviral activity. We tested the hypothesis that long-term interferon treatment would result in significant reduction in average telomere length in peripheral blood T lymphocytes. METHODS/PRINCIPAL FINDINGS: Using a flow cytometry-based telomere length assay on peripheral blood mononuclear cell samples from the Hepatitis-C Antiviral Long-term Treatment against Cirrhosis (HALT-C study, we measured T cell telomere lengths at screening and at months 21 and 45 in 29 Hepatitis-C virus infected subjects. These subjects had failed to achieve a sustained virologic response following 24 weeks of pegylated-interferon-alpha plus ribavirin treatment and were subsequently randomized to either a no additional therapy group or a maintenance dose pegylated-IFNα group for an additional 3.5 years. Significant telomere loss in naïve T cells occurred in the first 21 months in the interferon-alpha group. Telomere losses were similar in both groups during the final two years. Expansion of CD8(+CD45RA(+CD57(+ memory T cells and an inverse correlation of alanine aminotransferase levels with naïve CD8(+ T cell telomere loss were observed in the control group but not in the interferon-alpha group. Telomere length at screening inversely correlated with Hepatitis-C viral load and body mass index. CONCLUSIONS/SIGNIFICANCE: Sustained interferon-alpha treatment increased telomere loss in naïve T cells, and inhibited the accumulation of T cell memory expansions. The durability of this effect and consequences for immune senescence need to be defined.

  18. Assessment of individual radiosensitivity in human lymphocytes of cancer patients and its correlation with adverse side effects to radiation therapy

    CERN Document Server

    Di Giorgio, M; Busto, E; Mairal, L; Menendez, P; Roth, B; Sardi, M; Taja, M R; Vallerga, M B

    2003-01-01

    Background and purpose: Individual radiosensitivity is an inherent characteristic, associated with an increased reaction to ionizing radiation on the human body. Biological endpoints such as clonogenic survival, chromosome aberration formation and repair capacity of radiation-induced damage have been applied to evaluate individual radiosensitivity in vitro. 5%-7% of cancer patients develop adverse side effects to radiation therapy in normal tissues within the treatment field, which are referred as 'clinical radiation reactions' and include acute effects, late effects and cancer induction. It has been hypothesized that the occurrence and severity of these reactions are mainly influenced by genetic susceptibility to radiation. Additionally, the nature of the genetic disorders associated with hypersensitivity to radiotherapy suggests that DNA repair mechanisms are involved. Consequently, the characterization of DNA repair in lymphocytes through cytokinesis blocked micronucleus (MN) and alkaline single-cell micro...

  19. CR2-mediated activation of the complement alternative pathway results in formation of membrane attack complexes on human B lymphocytes

    DEFF Research Database (Denmark)

    Nielsen, C H; Marquart, H V; Prodinger, W M;

    2001-01-01

    Normal human B lymphocytes activate the alternative pathway of complement via complement receptor type 2 (CR2, CD21), that binds hydrolysed C3 (iC3) and thereby promotes the formation of a membrane-bound C3 convertase. We have investigated whether this might lead to the generation of a C5...... the alternative pathway. Blockade of the CR2 ligand-binding site with the monoclonal antibody FE8 resulted in 56 +/- 13% and 71 +/- 9% inhibition of the C3-fragment and MAC deposition, respectively, whereas the monoclonal antibody HB135, directed against an irrelevant CR2 epitope, had no effect. Blockade...... processes on CR2, indicate that MAC formation is a consequence of alternative pathway activation....

  20. Genetic adaptation of the antibacterial human innate immunity network

    Directory of Open Access Journals (Sweden)

    Lazarus Ross

    2011-07-01

    Full Text Available Abstract Background Pathogens have represented an important selective force during the adaptation of modern human populations to changing social and other environmental conditions. The evolution of the immune system has therefore been influenced by these pressures. Genomic scans have revealed that immune system is one of the functions enriched with genes under adaptive selection. Results Here, we describe how the innate immune system has responded to these challenges, through the analysis of resequencing data for 132 innate immunity genes in two human populations. Results are interpreted in the context of the functional and interaction networks defined by these genes. Nucleotide diversity is lower in the adaptors and modulators functional classes, and is negatively correlated with the centrality of the proteins within the interaction network. We also produced a list of candidate genes under positive or balancing selection in each population detected by neutrality tests and showed that some functional classes are preferential targets for selection. Conclusions We found evidence that the role of each gene in the network conditions the capacity to evolve or their evolvability: genes at the core of the network are more constrained, while adaptation mostly occurred at particular positions at the network edges. Interestingly, the functional classes containing most of the genes with signatures of balancing selection are involved in autoinflammatory and autoimmune diseases, suggesting a counterbalance between the beneficial and deleterious effects of the immune response.

  1. Native and recombinant herpes simplex virus type 1 envelope proteins induce human immune T-lymphocyte responses.

    Science.gov (United States)

    Torseth, J W; Cohen, G H; Eisenberg, R J; Berman, P W; Lasky, L A; Cerini, C P; Heilman, C J; Kerwar, S; Merigan, T C

    1987-05-01

    The abilities of whole herpes simplex virus type 1 (HSV-1) antigen (HSV-ag) and purified HSV-1 native and recombinant envelope proteins to stimulate in vitro T-lymphocyte responses were compared in patients with recurrent herpes labialis. Immunochemically purified preparations of native glycoproteins B, C, and D (ngB, ngC, ngD) from cultured HSV-1 as well as expressed recombinant plasmid preparations of gD (rgD-1t, rgD-45K) elicited lymphocyte proliferation (LT) and production of gamma interferon (IFN-gamma) and interleukin-2 (IL-2) only in seropositive individuals. The IFN-gamma induced by rgD-1t correlated with the time to the next herpetic lesion in 19 volunteers followed to recurrence (r = 0.69, P less than 0.008), although the magnitude and frequency of LT and IFN-gamma responses were lower with either recombinant or native purified antigens than with the whole-virus antigen. Combinations of ngB plus ngD or ngB plus ngC plus ngD stimulated more IFN-gamma, equivalent to whole-virus-antigen responses. Recombinant-derived human IL-2 also specifically increased LT and IFN-gamma responses in antigen-driven cultures. ngD stimulated IL-2 and LT responses similar to those of whole-virus antigen and higher than those of ngC. HSV-ag and ngB induced significantly higher titers of total IFN than could be accounted for by IFN-gamma; this was not seen for the other antigens, which induced only IFN-gamma. HSV-ag-driven Leu 2a-, plastic-nonadherent blood cells, unlike whole peripheral blood mononuclear cells, showed evidence of an increase and then a decline in the frequency of HSV-responsive cells after a lesion recurrence. These studies suggest that HSV-1 envelope proteins are capable of stimulating an immune T-helper-cell response which is associated with the prevention of human herpes simplex lesion recurrence. Although the whole virus probably contains additional important antigens, increasing concentrations or combinations of certain purified glycoproteins or the

  2. Unilateral adaptation of the human angular vestibulo-ocular reflex.

    Science.gov (United States)

    Migliaccio, Americo A; Schubert, Michael C

    2013-02-01

    A recent study showed that the angular vestibulo-ocular reflex (VOR) can be better adaptively increased using an incremental retinal image velocity error signal compared with a conventional constant large velocity-gain demand (×2). This finding has important implications for vestibular rehabilitation that seeks to improve the VOR response after injury. However, a large portion of vestibular patients have unilateral vestibular hypofunction, and training that raises their VOR response during rotations to both the ipsilesional and contralesional side is not usually ideal. We sought to determine if the vestibular response to one side could selectively be increased without affecting the contralateral response. We tested nine subjects with normal vestibular function. Using the scleral search coil and head impulse techniques, we measured the active and passive VOR gain (eye velocity / head velocity) before and after unilateral incremental VOR adaptation training, consisting of self-generated (active) head impulses, which lasted ≈ 15 min. The head impulses consisted of rapid, horizontal head rotations with peak-amplitude 15°, peak-velocity 150°/s and peak-acceleration 3,000°/s(2). The VOR gain towards the adapting side increased after training from 0.92 ± 0.18 to 1.11 ± 0.22 (+22.7 ± 20.2 %) during active head impulses and from 0.91 ± 0.15 to 1.01 ± 0.17 (+11.3 ± 7.5 %) during passive head impulses. During active impulses, the VOR gain towards the non-adapting side also increased by ≈ 8 %, though this increase was ≈ 70 % less than to the adapting side. A similar increase did not occur during passive impulses. This study shows that unilateral vestibular adaptation is possible in humans with a normal VOR; unilateral incremental VOR adaptation may have a role in vestibular rehabilitation. The increase in passive VOR gain after active head impulse adaptation suggests that the training effect is robust.

  3. Construction of a human recombinant polyclonal Fab fragment antibody library using peripheral blood lymphocytes of snake bitten victims

    Directory of Open Access Journals (Sweden)

    Motedayen, M.H.

    2015-12-01

    Full Text Available Human snake bitten poisoning is a serious threat in many tropical and subtropical countries such as Iran. The best acceptable treatment of envenomated humans is antivenoms; however they have a series of economic and medical problems and need more improvements. In this study a combinatorial human immunoglobulin gene library against some of Iranian snakes venoms was constructed. Total RNA prepared from peripheral blood lymphocytes of two recovered snake victims. RT-PCR was used for cDNA synthesis and amplification of the heavy (Fd segment and kappa light chains of IgG antibody. After digestion of the heavy chain with SpeI and XhoI and light chain with XbaI and SacI enzymes, inserted successively into the cloning vector pComb3x, and then recombinant vector transformed to TG1 bacteria to construct the Fab library. For determination insertion rate of Fab segment into cloning vector, plasmids of 12 clones of library were extracted and digested with SfiI. Length of amplified Fd and κ chains, were 650 - 750 bp. Primary library size was determined to contain 4.9×105 members out of which half of them contained the same size of Fab fragment. This result is comparable to some researchers and shows that this method could be appropriate tool for the production of human polyclonal Fab fragment antibodies for management of poisonous snake bitted victims.

  4. Adaptive Human aware Navigation based on Motion Pattern Analysis

    DEFF Research Database (Denmark)

    Tranberg, Søren; Svenstrup, Mikael; Andersen, Hans Jørgen;

    2009-01-01

    Respecting people’s social spaces is an important prerequisite for acceptable and natural robot navigation in human environments. In this paper, we describe an adaptive system for mobile robot navigation based on estimates of whether a person seeks to interact with the robot or not. The estimates...... are based on run-time motion pattern analysis compared to stored experience in a database. Using a potential field centered around the person, the robot positions itself at the most appropriate place relative to the person and the interaction status. The system is validated through qualitative tests...... in a real world setting. The results demonstrate that the system is able to learn to navigate based on past interaction experiences, and to adapt to different behaviors over time....

  5. Immune responses to recombinant hepatitis B virus vaccine in human immunodeficiency virus-1-infected patients with different CD4~+ T-lymphocyte

    Institute of Scientific and Technical Information of China (English)

    蔡琳

    2014-01-01

    Objective.To compare the difference of immune responses to hepatitis B virus(HBV)vaccine in human immunodeficiency virus(HIV)-1-infected patients with different CD4+T-lymphocyte counts.Methods HIV-1 infected patients who visited clinic at the Public Health Clinical Center of Chengdu were enrolled and divided in-+

  6. In Vitro genotoxic and antigenotoxic studies of Thai Noni fruit juice by chromosomal aberration and sister chromatid exchange assays in human lymphocytes

    OpenAIRE

    Treetip Ratanavalachai; Sumon Thitiorul; Pranee Nandhasri

    2008-01-01

    The genotoxic and antigenotoxic effects of Noni fruit juice produced in Thailand have been studied in human lymphocytes for chromosome aberration assay and sister chromatid exchange (SCE) assay in vitro. Treatment of Noni fruit juice(3.1-50 mg/ml) alone for 3 h did not significantly induce chromosomal aberration or SCE (p

  7. T-cell maturation in the human thymus and tonsil: peanut agglutinin binding T lymphocytes in thymus and tonsil differ in maturation stage.

    NARCIS (Netherlands)

    Schuurman, H J; Brekelmans, Pieter; Daemen, Toos; Broekhuizen, Roel; Kater, L

    1983-01-01

    The finding of peanut agglutinin (PNA) binding capacity, supposed to be a marker of immature lymphocytes, within the T-cell population of the human thymus (58%) and tonsil (10%) prompted the comparison of maturation stages of PNA binding (PNA+) and nonbinding (PNA-) T cells in both organs. The proli

  8. Folate depletion in human lymphocytes up-regulates p53 expression despite marked induction of strand breaks in exons 5 – 8 of the gene

    Science.gov (United States)

    Low dietary folate intake is associated with an elevated risk for carcinogenesis. One putative mechanism by which folate depletion promotes carcinogenesis is by inducing gene-specific strand breakage and impaired expression of affected genes. Primary human lymphocytes were cultured in media containi...

  9. Dose-dependence of the yield of chromosomal aberrations in human lymphocytes after irradiation of peripheral blood with monoenergetic neutrons of 2, 4 and 6 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Sevan' kaev, A.V.; Obaturov, G.M.; Nasonova, V.A.; Izmajlova, N.N. (Akademiya Meditsinskikh Nauk SSSR, Obninsk. Nauchno-Issledovatel' skij Inst. Meditsinskoj Radiologii)

    A study was made of the dose-dependence of the yield of chromosome aberrations in human lymphocyte culture irradiated at the G/sub 0/ stage with monoenergetic neutrons of 2, 4 and 6 MeV. The dose dependence was found to be linear all types of aberrations. The RBE of neutrons under study increased with the decrease in their energy.

  10. The magnitude and specificity of influenza A virus-specific cytotoxic T-lymphocyte responses in humans is related to HLA-A and -B phenotype

    NARCIS (Netherlands)

    A.C.M. Boon (Adrianus); G. de Mutsert (Gerrie); Y.M.F. Graus; R.A.M. Fouchier (Ron); K. Sintnicolaas (Krijn); G.F. Rimmelzwaan (Guus); A.D.M.E. Osterhaus (Albert)

    2002-01-01

    textabstractThe repertoire of human cytotoxic T-lymphocytes (CTL) in response to influenza A viruses has been shown to be directed towards multiple epitopes, with a dominant response to the HLA-A2-restricted M1(58-66) epitope. These studies, however, were performed with peripheral blood mononuclear

  11. Calcium-Sensing Receptor in Human Peripheral Blood T Lymphocytes Is Involved in the AMI Onset and Progression through the NF-κB Signaling Pathway.

    Science.gov (United States)

    Zeng, Jing-Ya; Du, Jing-Jing; Pan, Ying; Wu, Jian; Bi, Hai-Liang; Cui, Bao-Hong; Zhai, Tai-Yu; Sun, Yong; Sun, Yi-Hua

    2016-01-01

    Acute myocardial infarction (AMI) is a condition triggered by an inflammatory process that seriously affects human health. Calcium-sensing receptor (CaSR) in T lymphocytes is involved during the inflammation reaction. However, the relationship between them is not very clear. In this study, we collected human peripheral blood T lymphocytes from patients with AMI and in different stages of percutaneous coronary intervention (PCI) (at the onset of AMI, the first day after PCI (PCI-1), PCI-3, and PCI-5) to study the CaSR and NF-κB pathway protein expression, cytokine release and T cell apoptosis. The results showed that the expressions of CaSR, P-p65, Caspase-12, and the secretions of Th-1 and Th-2 type cytokines were increased at the onset of AMI, especially on the PCI-1. Meanwhile, the apoptosis rate of CD(3+), CD(4+) and CD(8+) T lymphocytes also increased. However, from PCI-3, all the indicators began to decline. In addition, we also found that positive CaSR small interfering RNA (siRNA) transfection in T lymphocytes and NF-κB pathway blocker Bay-11-7082 reversed the increased expressions of CaSR, P-p65, Caspase-12, reduced the secretions of Th-1 and Th-2 type cytokines, and decreased T lymphocytes apoptosis rate not only in the AMI patients but also in the normal controls. All of these results indicated that CaSR in the human peripheral blood T lymphocytes were involved in the AMI onset and progression, which probably was related to the NF-κB pathway. Our study demonstrated the relationship between AMI and CaSR, and will provide new effective prevention theory and new targets for drug treatment. PMID:27563892

  12. Microgravity and Cellular Consequences in Lymphocyte Function

    Science.gov (United States)

    Pellis, Neal R.; Sundaresan, Alamelu

    2004-01-01

    Mammalian cells adapt to the environment of low gravity and express a series of responses, some possibly from direct effects on cells and others based on environmental conditions created by microgravity. Human lymphocytes in microgravity culture are functionally diminished in activation and locomotion. Both processes are integral to optimal immune response to fight pathogens. The NASA Rotating-wall vessel (RWV) is a well-accepted analog for microgravity culture on the ground. Gene array experiments and immunoblotting identified upstream events in human lymphocytes adapting to microgravity analog culture. Microgravity induces selective changes, many of which are cell membrane related. Results showed that upstream of PKC in the T cell activation cascade, PLC-gamma and LAT are significantly diminished. ZAP 70 which controls LAT activation is also down regulated in modeled microgravity. Thus events governing cell shape might warrant attention in microgravity conditions. The goal of this study is to delineate response suites that are consequential, direct or indirect effects of the microgravity environment and which of these are essential to lymphocytes

  13. Study on the Interferation of the Concentration of Free Calcium in Peripheral Human Lymphocyte by Low Dose Penicillin, Using Fura-2 as Fluorescent Probe

    Institute of Scientific and Technical Information of China (English)

    Hai Yan WANG; Dan Dan WANG; Chun Gui ZHAO; Ye Hong ZHOU; Shao Min SHUANG; Chuan DONG

    2006-01-01

    The effect of penicillin on the human peripheral lymphocytes was studied by steady fluorescent technique and ratiometric fluorescence dye, Fura-2. The change of the free calcium concentration in cytosol was examined under different conditions. A characterization of Fura-2-Ca interaction in an isotonic saline solution showed that Ca2+ formed a 1:1 Fura-2-Ca complex with the apparent dissociation constant 1.81×10-7 mol/L. The mechanism, by which penicillin induced the decrease of [Ca2+]i, was discussed in detail. The low dose of penicillin might modify the lymphocytes' immunology response by interfering the increase in the intracellular free calcium concentration.

  14. In vitro genotoxicity and cytotoxicity of five new chemical compounds of plant origin by means of the human lymphocyte micronucleus assay.

    Science.gov (United States)

    Scarpato, R; Pistelli, L; Bertoli, A; Nieri, E; Migliore, L

    1998-04-01

    The micronucleus test in human peripheral lymphocytes is widely used in toxicology for the assessment of the genotoxic profile of chemical compounds of environmental concern. The aim of this study was to evaluate the genotoxic, cytotoxic and antimitotic activity of five new compounds isolated from Prunus africana Hook or from Bupleurum fruticosum L. The experiments were conducted only in vitro. Results showed that none of the plant extracts, tested over a wide range of concentrations, increased the frequency of micronuclei. Only compounds 2 and 5 were found to be toxic for phytohaemagglutinin-stimulated lymphocytes at the maximum dose used. reserved.

  15. Identification of a 145,000 Mr membrane protein as the C3d receptor (CR2) of human B lymphocytes.

    OpenAIRE

    Weis, J J; Tedder, T F; D.T. Fearon

    1984-01-01

    The C3d receptor (CR2) of human B lymphocytes mediates the binding to these cells of immune complexes that have activated the complement system and bear the fragments of C3, iC3b, C3d,g, and C3d. A 145,000 Mr membrane protein previously described as being recognized by the monoclonal antibody HB-5 and shown to be expressed only by B lymphocytes and B lymphoblastoid cell lines, such as Raji, was assessed for its possible identity as CR2. Treatment of Raji cells with HB-5 and goat F(ab')2 anti-...

  16. Lentiviral vector delivery of human interleukin-7 (hIL-7 to human immune system (HIS mice expands T lymphocyte populations.

    Directory of Open Access Journals (Sweden)

    Ryan M O'Connell

    Full Text Available Genetically modified mice carrying engrafted human tissues provide useful models to study human cell biology in physiologically relevant contexts. However, there remain several obstacles limiting the compatibility of human cells within their mouse hosts. Among these is inadequate cross-reactvitiy between certain mouse cytokines and human cellular receptors, depriving the graft of important survival and growth signals. To circumvent this problem, we utilized a lentivirus-based delivery system to express physiologically relevant levels of human interleukin-7 (hIL-7 in Rag2-/-gammac-/- mice following a single intravenous injection. hIL-7 promoted homeostatic proliferation of both adoptively transferred and endogenously generated T-cells in Rag2-/-gammac-/- Human Immune System (HIS mice. Interestingly, we found that hIL-7 increased T lymphocyte numbers in the spleens of HIV infected HIS mice without affecting viral load. Taken together, our study unveils a versatile approach to deliver human cytokines to HIS mice, to both improve engraftment and determine the impact of cytokines on human diseases.

  17. Human neutrophil elastase inhibitors in innate and adaptive immunity.

    Science.gov (United States)

    Fitch, P M; Roghanian, A; Howie, S E M; Sallenave, J-M

    2006-04-01

    Recent evidence shows that human neutrophil elastase inhibitors can be synthesized locally at mucosal sites. In addition to efficiently targeting bacterial and host enzymes, they can be released in the interstitium and in the lumen of mucosa, where they have been shown to have antimicrobial activities, and to activate innate immune responses. This review will address more particularly the pleiotropic functions of low-molecular-mass neutrophil elastase inhibitors [SLPI (secretory leucocyte proteinase inhibitor) and elafin] and, more specifically, their role in the development of the adaptive immune response. PMID:16545094

  18. Cytogenetic damage in human blood lymphocytes exposed in vitro and in vivo to space-relevant HZE-particles

    Science.gov (United States)

    Lee, Ryonfa; Nasonova, Elena; Sommer, Sylvester; Hartel, Carola; Ritter, Sylvia

    During space missions astronauts are exposed to cosmic radiations which are different from natural background radiation on Earth in both quantity and quality. Dose rate in space environment is at least 100 times higher than that on Earth. In addition, the natural radiation on Earth consists mainly of X-, γ-rays and α-emitters, while in space charged particles from protons to iron ions are predominant. The composition of radiation environment of outer space is well understood, however, due to a lack of data on the biological effects of dose, dose-rate and especially HZE (high charge Z and energy E) particles, large uncertainties exist in estimating the health risks for long-term space mission. To contribute to this issue, we investigated cytogenetic damage induced by heavy charged particles in human lymphocytes, since chromosome aberration yield is a biomarker showing an association with cancer risk. Lymphocytes collected from a healthy donor were irradiated with carbon ions (C-ions) in vitro with various energies (11.4 to 400 MeV/u; LET values 11 to 175 keV/µm) at either UNILAC or SIS facility (GSI, Germany) or exposed to X-rays. Additionally, peripheral blood was obtained from prostate cancer patients, treated with intensity modulated radiation therapy (IMRT) or IMRT combined with C-ion boost. Samples were taken before, during and after the radiotherapy. Chromosome samples were stained with FPG-technique to enable aberration analysis in 1st cycle metaphases. After in vitro exposure to C-ions, RBE values for the induction of chromosome aberrations increased with sampling time. The effect was most pronounced in samples exposed to 175 keV/µm C-ions and can be attributed to a pronounced cell cycle delay of heavily damaged cells. Thus, for a reliable risk assessment, the effect of selective cell cycle delay following particle exposure should be taken into account. M-FISH analysis of selected samples to assess aberration quality revealed higher frequencies of

  19. Cloning, sequence analysis, and expression of the large subunit of the human lymphocyte activation antigen 4F2

    Energy Technology Data Exchange (ETDEWEB)

    Lumadue, J.A.; Glick, A.B.; Ruddle, F.H.

    1987-12-01

    Among the earliest expressed antigens on the surface of activated human lymphocytes is the surface antigen 4F2. The authors have used DNA-mediated gene transfer and fluorescence-activated cell sorting to obtain cell lines that contain the gene encoding the large subunit of the human 4F2 antigen in a mouse L-cell background. Human DNAs cloned from these cell lines were subsequently used as hybridization probes to isolate a full-length cDNA clone expressing 4F2. Sequence analysis of the coding region has revealed an amino acid sequence of 529 residues. Hydrophobicity plotting has predicted a probable structure for the protein that includes an external carboxyl terminus, an internal leader sequence, a single hydrophobic transmembrane domain, and two possible membrane-associated domains. The 4F2 cDNA detects a single 1.8-kilobase mRNA in T-cell and B-cell lines. RNA gel blot analysis of RNA derived from quiescent and serum-stimulated Swiss 3T3 fibroblasts reveals a cell-cycle modulation of 4F2 gene expression: the mRNA is present in quiescent fibroblasts but increases 8-fold 24-36 hr after stimulation, at the time of maximal DNA synthesis.

  20. Characterization of CRTAM gene promoter: AP-1 transcription factor control its expression in human T CD8 lymphocytes.

    Science.gov (United States)

    Valle-Rios, Ricardo; Patiño-Lopez, Genaro; Medina-Contreras, Oscar; Canche-Pool, Elsy; Recillas-Targa, Felix; Lopez-Bayghen, Esther; Zlotnik, Albert; Ortiz-Navarrete, Vianney

    2009-10-01

    Class-I MHC-restricted T-cell associated molecule (CRTAM) is a member of the Nectin-like adhesion molecule family. It is rapidly induced in NK, NKT and CD8(+) T cells. Interaction with its ligand Nectin-like 2 results in increased secretion of IFN-gamma by activated CD8(+) T lymphocytes. Through sequential bioinformatic analyses of the upstream region of the human CRTAM gene, we detected cis-elements potentially important for CRTAM gene transcription. Analyzing 2kb upstream from the ATG translation codon by mutation analysis in conjunction with luciferase reporter assays, electrophoretic mobility shify assay (EMSA) and supershift assays, we identified an AP-1 binding site, located at 1.4kb from the ATG translation codon of CRTAM gene as an essential element for CRTAM expression in activated but not resting human CD8(+) T cells. CRTAM expression was reduced in activated CD8(+) T cells treated with the JNK inhibitor SP600125, indicating that CRTAM expression is driven by the JNK-AP-1 signaling pathway. This study represents the first CRTAM gene promoter analysis in human T cells and indicates that AP-1 is a positive transcriptional regulator of this gene, a likely important finding because CRTAM has recently been shown to play a role in IFN-gamma and IL-17 production and T cell proliferation.

  1. HIV-1 Capsid Assembly Inhibitor (CAI Peptide: Structural Preferences and Delivery into Human Embryonic Lung Cells and Lymphocytes

    Directory of Open Access Journals (Sweden)

    Klaus Braun, Martin Frank, Rüdiger Pipkorn, Jennifer Reed, Herbert Spring, Jürgen Debus, Bernd Didinger, Claus-Wilhelm von der Lieth, Manfred Wiessler, Waldemar Waldeck

    2008-01-01

    Full Text Available The Human immunodeficiency 1 derived capsid assembly inhibitor peptide (HIV-1 CAI-peptide is a promising lead candidate for anti-HIV drug development. Its drawback, however, is that it cannot permeate cells directly. Here we report the transport of the pharmacologically active CAI-peptide into human lymphocytes and Human Embryonic Lung cells (HEL using the BioShuttle platform. Generally, the transfer of pharmacologically active substances across membranes, demonstrated by confocal laser scanning microscopy (CLSM, could lead to a loss of function by changing the molecule's structure. Molecular dynamics (MD simulations and circular dichroism (CD studies suggest that the CAI-peptide has an intrinsic capacity to form a helical structure, which seems to be critical for the pharmacological effect as revealed by intensive docking calculations and comparison with control peptides. This coupling of the CAI-peptide to a BioShuttle-molecule additionally improved its solubility. Under the conditions described, the HIV-1 CAI peptide was transported into living cells and could be localized in the vicinity of the mitochondria.

  2. HIV-1 Capsid Assembly Inhibitor (CAI) Peptide: Structural Preferences and Delivery into Human Embryonic Lung Cells and Lymphocytes

    Science.gov (United States)

    Braun, Klaus; Frank, Martin; Pipkorn, Rüdiger; Reed, Jennifer; Spring, Herbert; Debus, Jürgen; Didinger, Bernd; von der Lieth, Claus-Wilhelm; Wiessler, Manfred; Waldeck, Waldemar

    2008-01-01

    The Human immunodeficiency virus 1 derived capsid assembly inhibitor peptide (HIV-1 CAI-peptide) is a promising lead candidate for anti-HIV drug development. Its drawback, however, is that it cannot permeate cells directly. Here we report the transport of the pharmacologically active CAI-peptide into human lymphocytes and Human Embryonic Lung cells (HEL) using the BioShuttle platform. Generally, the transfer of pharmacologically active substances across membranes, demonstrated by confocal laser scanning microscopy (CLSM), could lead to a loss of function by changing the molecule's structure. Molecular dynamics (MD) simulations and circular dichroism (CD) studies suggest that the CAI-peptide has an intrinsic capacity to form a helical structure, which seems to be critical for the pharmacological effect as revealed by intensive docking calculations and comparison with control peptides. This coupling of the CAI-peptide to a BioShuttle-molecule additionally improved its solubility. Under the conditions described, the HIV-1 CAI peptide was transported into living cells and could be localized in the vicinity of the mitochondria. PMID:18695744

  3. T Lymphocyte Potential Marks the Emergence of Definitive Hematopoietic Progenitors in Human Pluripotent Stem Cell Differentiation Cultures

    Directory of Open Access Journals (Sweden)

    Marion Kennedy

    2012-12-01

    Full Text Available The efficient generation of hematopoietic stem cells from human pluripotent stem cells is dependent on the appropriate specification of the definitive hematopoietic program during differentiation. In this study, we used T lymphocyte potential to track the onset of definitive hematopoiesis from human embryonic and induced pluripotent stem cells differentiated with specific morphogens in serum- and stromal-free cultures. We show that this program develops from a progenitor population with characteristics of hemogenic endothelium, including the expression of CD34, VE-cadherin, GATA2, LMO2, and RUNX1. Along with T cells, these progenitors display the capacity to generate myeloid and erythroid cells. Manipulation of Activin/Nodal signaling during early stages of differentiation revealed that development of the definitive hematopoietic progenitor population is not dependent on this pathway, distinguishing it from primitive hematopoiesis. Collectively, these findings demonstrate that it is possible to generate T lymphoid progenitors from pluripotent stem cells and that this lineage develops from a population whose emergence marks the onset of human definitive hematopoiesis.

  4. Comparative cytotoxic and genotoxic effects of permethrin and its nanometric form on human erythrocytes and lymphocytes in vitro.

    Science.gov (United States)

    Sundaramoorthy, Rajiv; Velusamy, Yuvaraj; Balaji, A P B; Mukherjee, Amitava; Chandrasekaran, Natarajan

    2016-09-25

    The research on the novel pesticides such as nanopesticides has become inevitable to control the mosquito population. Nanopermethrin (NP), one of such kind was formulated in pesticide loaded oil-in-water (o/w) microemulsion by rapid evaporation. Even though NP possess improved efficacy against the target pests, the toxicological investigation on the human or mammalian system remains unexplored. So, the present study focused on a comparative investigation of the cytotoxic and genotoxic effects of NP in vitro and its commercial parental bulk form of permethrin (BP) on human peripheral erythrocyte/lymphocyte by erythrocyte morphology analysis, cell viability assay, and cytokinesis-block micronucleus (CBMN) assay. The NP and BP concentrations (10, 25, 50 and 100 μg/ml) interacted with human blood cells, and the morphological changes were observed using a phase contrast microscope. The drastic increase of echinocyte was observed at 24, 48 and 72 h treatment as compared with the control. The cell viability studies have shown the significant decrease with increase in NP and BP concentration. CBMN study showed a series correlation in the number of micronuclei, bridge, bud, trinucleated and tetranucleated when interacted with different levels of NP and BP, as comparative to control *p < 0.05, **p < 0.001, ***p < 0.0001. PMID:27502151

  5. Effects of Sterigmatocystin, Deoxynivalenol and Aflatoxin G1 on Apoptosis of Human Peripheral Blood Lymphocytes in vitro

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective To explore the effects of Sterigmatocystin (ST), Deoxynivalenol (DON) and Aflatoxin G1 (AFG1) on apoptosis of human peripheral blood lymphocytes (HPBLs) in vitro and thus to further elucidate the putative roles of these three mycotoxins on human immunosystem. Methods The effects of ST, DON and AFG1 on apoptosis of HPBLs were studied with cell culture, flow cytometric (FCM) DNA analysis and DNA agarose gel electrophoresis. Results DNA agarose gel electrophoresis results showed the characteristic "ladder" pattern of apoptosis in HPBLs treated with ST, DON and AFG1. Flow cytometric DNA analysis revealed that typical subdiploid peaks of apoptosis in DNA histogram could be seen in all groups treated with the three mycotoxins. Significant time-effect and dose-effect relationships were found between the apoptosis rates and treatment time as well as concentrations of the three mycotoxins. Conclusion ST, DON and AFG1 can induce apoptosis of HPBLs in vitro and may have some negative effects on human immunosystem.

  6. Rapid rejoining of DNA strand breaks in resting human lymphocytes after irradiation by low doses of 60Co γ rays or 14.6-MeV neutrons

    International Nuclear Information System (INIS)

    The production and repair of DNA strand breaks was studied in human lymphocytes by means of a sensitive fluorometric technique. Lymphocytes were isolated by conventional methods and air-equilibrated suspensions were irradiated by low doses (less than or equal to 2 Gy) of either 60Co γ rays or 14.6-MeV neutrons at 00C. The apparent yield of initial strand breaks induced by neutrons was only 36% of that induced by γ rays, in agreement with the observations of other workers. Resting lymphocytes were found to be proficient in their ability to rejoin γ-induced strand breaks at 370C; rejoining followed biphasic kinetics, with 70% of the breaks disappearing with a half-life of about 3 min. Although the initial number of breaks induced by neutron irradiation was low, after 20 min of incubation the residual number of breaks was very similar for the two forms of radiation

  7. Human lymphocyte damage and phosphorylation of H2AX and ATM induced by γ-rays

    International Nuclear Information System (INIS)

    Objective: To investigate 60Co γ-ray induced damage in lymphocytes and the relationship between doses of 60Co γ-ray irradiation and the levels of phosphorylated H2AX and ATM. Methods: Cells were irradiated with 60Co γ-rays in the range of 0-8 Gy. The levels of phosphorylated H2AX and ATM were detected by Western blot and FACScan,respectively. The micronucleus(MN)was analyzed by CB method to evaluate DNA damage. Results: FACScan results showed the dose-effect relationship of γ-H2AX expression were linear.square at 0.5 h post-irradiation to different doses, and the fitting curve was shown as Y=3.96+11.29D-0.45D2. The level of phosphorylated ATM (p-ATM) was not changed significantly by using the same method. Western blot showed that p-ATM protein expression was significantly increased after irradiation compared with sham, irradiated group. The MN assay which represented DNA damage was sensitive to different doses. Conclusions: γ-ray irradiation could induce the phosphorylation of H2AX and ATM, which may play an important role in indicating DNA damage. Both of H2AX and ATM have the potential as sensitive biomarker and biodosimeter for radiation damage. (authors)

  8. Growth hormone-like factor produced by the tapeworm, Spirometra mansonoides, displaces human growth hormone (hGH) from its receptors on cultured human lymphocytes

    International Nuclear Information System (INIS)

    An analogue of hGH isolated from plerocercoids of the tapeworm Spirometra mansonoides displaces [125I]hGH from its receptors in rabbit, rat, and hamster liver membranes. Biologically, plerocercoid growth factor (PGF) is more similar to hGH than to other mammalian GH's but has not been shown to bond human cells. Receptors specific for hGH have been described on cultured human lymphocytes (IM-9). In this study, the authors compared the binding of PGF and hGH in IM-9 cells and in rabbit hepatic membranes. IM-9 lymphocytes (12 x 106 cells/tube) were incubated with [125I]hGH and increasing concentrations of hGH (ng/ml) or PGF (serial dilutions) for 90 min at 300 C. Specific binding (B0 - NSB) was determined for each dose of hGH or PGF and the binding curves were analyzed by logit-log regression. The results show that PGF displaced [125I]hGH from human cells in a dose dependent manner (r = 0.98). Based on the IM-9 assay, 1 ml of the PGF had an activity equivalent to 625 ng of the hGH standard (ngE). However, the binding activity of the PGF in the rabbit liver RRA was 1653 ngE/ml, indicating that the binding potency of PGF in IM-9 cells was only 38% of that in the rabbit liver. These results clearly demonstrate that PGF binds hGH receptors in cells of human origin, suggesting that PGF will be effective in humans

  9. Cytogenetic status and oxidative DNA-damage induced by atorvastatin in human peripheral blood lymphocytes: Standard and Fpg-modified comet assay

    International Nuclear Information System (INIS)

    To investigate the genotoxic potential of atorvastatin on human lymphocytes in vitro standard comet assay was used in the evaluation of basal DNA damage and to investigate possible oxidative DNA damage produced by reactive oxygen species (ROS) Fpg-modified version of comet assay was also conducted. In addition to these techniques the new criteria for scoring micronucleus test were applied for more complete detection of baseline damage in binuclear lymphocytes exposed to atorvastatin 80 mg/day in different time periods by virtue of measuring the frequency of micronuclei, nucleoplasmic bridges and nuclear buds. All parameters obtained with the standard comet assay and Fpg-modified comet assay were significantly higher in the treated than in control lymphocytes. The Fpg-modified comet assay showed a significantly greater tail length, tail intensity, and tail moment in all treated lymphocytes than did the standard comet assay, which suggests that oxidative stress is likely to be responsible for DNA damage. DNA damage detected by the standard comet assay indicates that some other mechanism is also involved. In addition to the comet assay, a total number of micronuclei, nucleoplasmic bridges and nuclear buds were significantly higher in the exposed than in controlled lymphocytes. Regression analyses showed a positive correlation between the results obtained by the comet (Fpg-modified and standard) and micronucleus assay. Overall, the study demonstrated that atorvastatin in its highest dose is capable of producing damage on the level of DNA molecule and cell

  10. In vitro lymphocyte proliferation response to therapeutic insulin components. Evidence for genetic control by the human major histocompatibility complex.

    OpenAIRE

    Mann, D L; Mendell, N; Kahn, C R; Johnson, A H; Rosenthal, A

    1983-01-01

    Genes in the major histocompatibility complex of mice and guinea pigs control immunologic responsiveness to insulins from other animal species. In order to determine if similar genetic control exists in man, we have examined lymphocyte proliferation responses to components of therapeutic insulins by employing lymphocytes from diabetic patients that receive insulin. Distinct groups of individuals demonstrated positive lymphocyte proliferative responses to beef insulin, beef and pork insulin, b...

  11. Changes in human lymphocyte subpopulations in tonsils and regional lymph nodes of human head and neck squamous carcinoma compared to control lymph nodes

    Directory of Open Access Journals (Sweden)

    González-Femandez África

    2001-04-01

    Full Text Available Abstract Background Lymphoid tissues constitute basic structures where specific immune responses take place. This leads to the development of germinal centres (GCs, migration of cells and the generation of memory cells. Here, we have compared human tumour reactive lymph nodes and tonsils with control lymph nodes. Results The study by flow cytometry shows that in control lymph nodes the majority of cells were naive T-lymphocytes (CD45RA+/CD7+. In reactive nodes, although the percentage of CD45RO+ T cells remains constant, there is an increase in the number of B-lymphocytes, and a reduction in naive T cells. The percentage of cells expressing CD69 was similar in reactive nodes and in controls. In both cases, we have found two populations of B cells of either CD69- or CD69dull. Two populations of T cells, which are either negative for CD69 or express it in bright levels (CD69bright, were also found. The analysis of tissue sections by confocal microscopy revealed differences between control, tonsils and tumor reactive lymph nodes. In control lymph nodes, CD19 B cells are surrounded by a unique layer of CD69bright/CD45RO+ T cells. GCs from tonsils and from tumour reactive nodes are mainly constituted by CD19 B cells and have four distinct layers. The central zone is composed of CD69- B cells surrounded by CD69bright/CD45RO+ T cells. The mantle region has basically CD69dull B-lymphocytes and, finally, there is an outer zone with CD69-/CD45RO+ T cells. Conclusions Human secondary lymphoid organs react with an increase in the proportion of B lymphocytes and a decrease in the number of CD45RA+ T cells (naive. In tonsils, this is due to chronic pathogen stimulation, whereas in lymph nodes draining head and neck carcinomas the reaction is prompted by surrounded tumors. During this process, secondary lymphoid organs develop secondary follicles with a special organization of T and B cells in consecutive layers, that are described here by confocal microscopy

  12. Studying the synergistic damage effects induced by 1.8 GHz radiofrequency field radiation (RFR) with four chemical mutagens on human lymphocyte DNA using comet assay in vitro

    International Nuclear Information System (INIS)

    The aim of this investigation was to study the synergistic DNA damage effects in human lymphocytes induced by 1.8 GHz radiofrequency field radiation (RFR, SAR of 3 W/kg) with four chemical mutagens, i.e. mitomycin C (MMC, DNA crosslinker), bleomycin (BLM, radiomimetic agent), methyl methanesulfonate (MMS, alkylating agent), and 4-nitroquinoline-1-oxide (4NQO, UV-mimetic agent). The DNA damage of lymphocytes exposed to RFR and/or with chemical mutagens was detected at two incubation time (0 or 21 h) after treatment with comet assay in vitro. Three combinative exposure ways were used. Cells were exposed to RFR and chemical mutagens for 2 and 3 h, respectively. Tail length (TL) and tail moment (TM) were utilized as DNA damage indexes. The results showed no difference of DNA damage indexes between RFR group and control group at 0 and 21 h incubation after exposure (P > 0.05). There were significant difference of DNA damage indexes between MMC group and RFR + MMC co-exposure group at 0 and 21 h incubation after treatment (P 0.05). The experimental results indicated 1.8 GHz RFR (SAR, 3 W/kg) for 2 h did not induce the human lymphocyte DNA damage effects in vitro, but could enhance the human lymphocyte DNA damage effects induced by MMC and 4NQO. The synergistic DNA damage effects of 1.8 GHz RFR with BLM or MMS were not obvious

  13. The Pavonia xanthogloea (Ekman, Malvaceae: Phenolic compounds quantification, anti-oxidant and cytotoxic effect on human lymphocytes cells

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    Clarice Pinheiro Mostardeiro

    2014-01-01

    Full Text Available Introduction: Pavonia xanthogloea is traditionally used as an antimicrobial and anti-tumour medicine in Southern Brazilian region. However, investigations about this species are still incipient. Hypothesis Tested: The study postulated that P. xanthologea specie present some phenolic compound and present some biological properties as anti-oxidant and cytoprotective effect against oxidative stress. Materials and Methods: The content of eight phenolic molecules in the crude ethanolic extract of the aerial part of P. xanthogloea and its five fractions (hexane, dichloromethane, ethyl-acetate, n-butanol, and water was determined by heterotrophic plate count method. The anti-oxidant capacity of the extract and the fractions was determined by 1,1-diphenyl-2-picryl-hydrazyl assay. The potential anti-oxidant and cytoprotective effect was also analyzed in human lymphocyte culture treated with extract/fractions at different concentrations with and without oxidative stress generated by hydrogen peroxide (H 2 O 2 and sodium nitroprusside (SNP exposition. Results: Tiliroside was the molecule detected in all extract. Water and ethyl-acetate fractions showed the highest radical-scavenging activity. The crude extract, hexane, water, and n-butanol reversed the higher reactive oxygen specie levels generated by H 2 O 2 and SNP to levels similar to those observed in the control group. In addition, crude extract, hexane, ethyl-acetate and n-butanol did not caused cytotoxicity, whereas water fraction was cytotoxic at higher concentration tested here (300 μg/mL. The cytotoxicity reversion caused by SNP exposition was concentration-dependent of the extract and fractions. However, dichloromethane fraction increased cell mortality in all concentrations investigated and was not able to decrease cell death in the lymphocytes exposed to SNP. Conclusion: The results suggest potential medicine use of this species.

  14. Human lung tissue macrophages, but not alveolar macrophages, express matrix metalloproteinases after direct contact with activated T lymphocytes.

    Science.gov (United States)

    Ferrari-Lacraz, S; Nicod, L P; Chicheportiche, R; Welgus, H G; Dayer, J M

    2001-04-01

    Human alveolar macrophages (AM) and lung tissue macrophages (LTM) have a distinct localization in the cellular environment. We studied their response to direct contact with activated T lymphocytes in terms of the production of interstitial collagenase (MMP-1), 92-kD gelatinase (MMP-9), and of TIMP-1, one of the counter-regulatory tissue inhibitors of metalloproteinases. Either AM obtained by bronchoalveolar lavage or LTM obtained by mincing and digestion of lung tissue were exposed for 48 h to plasma membranes of T lymphocytes previously activated with phorbol myristate acetate and phytohemagglutinin for 24 h. Membranes of activated T cells strongly induced the production of MMP-1, MMP-9, and TIMP-1 exclusively in LTM but not in AM, whereas membranes from unstimulated T cells failed to induce the release of MMPs. Both populations of mononuclear phagocytes spontaneously released only small amounts of MMPs and TIMP-1. Similar results were obtained when MMP and TIMP-1 expression was analyzed at pretranslational and biosynthetic levels, respectively. Blockade experiments with cytokine antagonists revealed the involvement of T-cell membrane-associated interleukin-1 and tumor necrosis factor-alpha in MMP production by LTM upon contact with T cells. These data suggest that the ability of lung macrophages to produce MMPs after direct contact with activated T cells is related to the difference in phenotype of mononuclear phagocytes and cell localization. In addition, these observations indicate that cell-cell contact represents an important biological mechanism in potentiating the inflammatory response of mononuclear phagocytes in the lungs. PMID:11306438

  15. Age and smoking habit influence on the spontaneous and radiation induced frequencies of the micronucleus in human lymphocytes

    International Nuclear Information System (INIS)

    Several endpoints have been used for monitoring human population that have been exposed at work or in the environment to genotoxic agents, particularly to ionizing radiation. The cytokinesis-block micronucleus (MN) assay in peripheral lymphocytes is a reliable method for evaluating radiation induced chromosomal damage (DNA breaks and mitotic spindle disturbances) and thus, a suitable dosimeter for estimating in vivo whole body exposures. A research to determine the influence of age, sex and life style factors (smoking habits) on the MN spontaneous and radiation induced frequencies was carried out in order to define the use of this assay in Biological Dosimetry. The estimation of MN frequencies was analyzed in lymphocytes cultures from 50 health donors aged between 4 and 60 years. Based on the smoking habits, they were divided into 2 groups. A fraction of the sample was irradiated in vitro with γ-rays in the range of 0.35 Gy to 4 Gy. A statistically significant influence on the spontaneous MN frequency was observed (R2 = 0.59) when the variables age and smoking habit were analyzed, and a statistically significant influence on the radiation induced MN frequency was also obtained (R2 = 0.86) when dose, age and smoking habit were studied. Sex did not influence significantly MN variability, but there was a greater dispersion in the results obtained from female donors, when compared to males, possibly due to the loss of X chromosomes. The comparison of the data from smoking donors to the data from non smoking donors supports the convenience of taking into account the smoking habit for estimating in vivo whole body exposure to γ-rays for doses below 2 Gy. (authors). 8 refs., 3 figs., 2 tabs

  16. Adaptation or exaptation? The case of the human hand

    Indian Academy of Sciences (India)

    Marta Linde-Medina

    2011-09-01

    A controversy of relevance to the study of biological form involves the concept of adaptation. This controversy is illustrated by the structure and function of the human hand. A review of the principal definitions of adaptation points to two main problems: (1) they are qualitative and make reference to the whole structure (or substructural feature) and (2) they are based on the idea of natural selection as a moulding factor. The first problem would be solved by a definition that encompasses quantitative measures of the effects of selection, drawing on new advances in the comparative method. The second problem is deeper and presents greater conceptual difficulties. I will argue that the idea of natural selection as a moulding factor depends on the notion of a genetic program for development. But regarding the hand, experimental evidence on limb development challenges the idea of a genetic program for skeletal pattern formation, undermining a simple application of standard adaptationist concepts. These considerations lead to a revised definition of adaptation and interpretation of the evolutionary determinants of the hand’s form.

  17. Cardiovascular adaptations supporting human exercise-heat acclimation.

    Science.gov (United States)

    Périard, Julien D; Travers, Gavin J S; Racinais, Sébastien; Sawka, Michael N

    2016-04-01

    This review examines the cardiovascular adaptations along with total body water and plasma volume adjustments that occur in parallel with improved heat loss responses during exercise-heat acclimation. The cardiovascular system is well recognized as an important contributor to exercise-heat acclimation that acts to minimize physiological strain, reduce the risk of serious heat illness and better sustain exercise capacity. The upright posture adopted by humans during most physical activities and the large skin surface area contribute to the circulatory and blood pressure regulation challenge of simultaneously supporting skeletal muscle blood flow and dissipating heat via increased skin blood flow and sweat secretion during exercise-heat stress. Although it was traditionally held that cardiac output increased during exercise-heat stress to primarily support elevated skin blood flow requirements, recent evidence suggests that temperature-sensitive mechanisms may also mediate an elevation in skeletal muscle blood flow. The cardiovascular adaptations supporting this challenge include an increase in total body water, plasma volume expansion, better sustainment and/or elevation of stroke volume, reduction in heart rate, improvement in ventricular filling and myocardial efficiency, and enhanced skin blood flow and sweating responses. The magnitude of these adaptations is variable and dependent on several factors such as exercise intensity, duration of exposure, frequency and total number of exposures, as well as the environmental conditions (i.e. dry or humid heat) in which acclimation occurs. PMID:26905458

  18. Protection by antioxidants against toxicity and apoptosis induced by the sulphur mustard analog 2-chloroethylethyl sulphide (CEES) in Jurkat T cells and normal human lymphocytes

    OpenAIRE

    Han, Suhua; Espinoza, Luis A; Liao, Hongling; Boulares, A Hamid; Smulson, Mark E.

    2004-01-01

    The mechanism of toxicity of sulphur mustard was investigated by examining the biochemical effects of the analog 2-chloroethylethyl sulphide (CEES) in both human Jurkat cells as well as normal human lymphocytes.Exposure of both types of cells to CEES resulted in a marked decrease in the intracellular concentration of the reduced form of glutathione (GSH), and CEES-induced cell death was potentiated by L-buthionine sulphoximine, an inhibitor of GSH synthesis.CEES increased the endogenous produ...

  19. Serum amyloid A-derived peptides, present in human rheumatic synovial fluids, induce the secretion of interferon-gamma by human CD(4)(+) T-lymphocytes.

    Science.gov (United States)

    Yavin, E J; Preciado-Patt, L; Rosen, O; Yaron, M; Suessmuth, R D; Levartowsky, D; Jung, G; Lider, O; Fridkin, M

    2000-04-28

    Serum amyloid A (SAA) is a major acute-phase protein whose biochemical functions remain largely obscure. Human rheumatic synovial fluids were screened by high performance liquid chromatography mass spectrometry for SAA-derived peptides, specifically the sequence AGLPEKY (SAA(98-104)) which was previously shown to modulate various leukocyte functions. Two such fluids were found to contain a truncated version of SAA(98-104). Synthetic SAA(98-104) and several of its analogs were shown capable of binding isolated human CD(4)(+) T-lymphocytes and stimulating them to produce interferon-gamma. Given the high acute-phase serum level of SAA and its massive proteolysis by inflammatory related enzymes, SAA-derived peptides may be involved in host defense mechanisms. PMID:10788622

  20. Exposure to negatively charged-particle dominant air-conditions on human lymphocytes in vitro activates immunological responses.

    Science.gov (United States)

    Nishimura, Yasumitsu; Takahashi, Kazuaki; Mase, Akinori; Kotani, Muneo; Ami, Kazuhisa; Maeda, Megumi; Shirahama, Takashi; Lee, Suni; Matsuzaki, Hidenori; Kumagai-Takei, Naoko; Yoshitome, Kei; Otsuki, Takemi

    2015-12-01

    Indoor air-conditions may play an important role in human health. Investigation of house conditions that promote health revealed that negatively charged-particle dominant indoor air-conditions (NAC) induced immune stimulation. NAC was established using fine charcoal powder on walls and ceilings and utilizing forced negatively charged particles (approximate diameter: 20 nm) dominant in indoor air-conditions created by applying an electric voltage (72 V) between the backside of the walls and the ground. We reported previously that these conditions induced a slight and significant increase of interleukin-2 during 2.5 h stay, and an increase of natural killer (NK) cell cytotoxicity, when examining human subjects after a two-week night stay under these conditions. In the present study, we investigated whether exposure to NAC in vitro affects immune conditions. Although the concentrations of particles were different, an incubator for cell culture with NAC was set and cellular compositions and functions of various freshly isolated human lymphocytes derived from healthy donors were assayed in the NAC incubator and compared with those of cultures in a standard (STD) incubator. Results showed that NAC cultivation caused an increase of CD25 and PD-1 expressing cells in the CD4 positive fraction, enhancement of NK cell cytotoxicity, production of interferon-y (IFNγ), and slight enhancement of regulatory T cell function. In addition, the formula designated as the "immune-index" clearly differed between STD and NAC culture conditions. Thus, NAC conditions may promote human health through slight activation of the immune system against cancer cells and virus infection as shown by this in vitro study and our previously reported human studies.

  1. Quantifying the impact of human immunodeficiency virus-1 escape from cytotoxic T-lymphocytes.

    Directory of Open Access Journals (Sweden)

    Ulrich D Kadolsky

    Full Text Available HIV-1 escape from the cytotoxic T-lymphocyte (CTL response leads to a weakening of viral control and is likely to be detrimental to the patient. To date, the impact of escape on viral load and CD4(+ T cell count has not been quantified, primarily because of sparse longitudinal data and the difficulty of separating cause and effect in cross-sectional studies. We use two independent methods to quantify the impact of HIV-1 escape from CTLs in chronic infection: mathematical modelling of escape and statistical analysis of a cross-sectional cohort. Mathematical modelling revealed a modest increase in log viral load of 0.051 copies ml(-1 per escape event. Analysis of the cross-sectional cohort revealed a significant positive association between viral load and the number of "escape events", after correcting for length of infection and rate of replication. We estimate that a single CTL escape event leads to a viral load increase of 0.11 log copies ml(-1 (95% confidence interval: 0.040-0.18, consistent with the predictions from the mathematical modelling. Overall, the number of escape events could only account for approximately 6% of the viral load variation in the cohort. Our findings indicate that although the loss of the CTL response for a single epitope results in a highly statistically significant increase in viral load, the biological impact is modest. We suggest that this small increase in viral load is explained by the small growth advantage of the variant relative to the wildtype virus. Escape from CTLs had a measurable, but unexpectedly low, impact on viral load in chronic infection.

  2. 1α,25-Dihydroxyvitamin D3 inhibits γ-interferon synthesis by normal human peripheral blood lymphocytes

    International Nuclear Information System (INIS)

    1α,25-Dihydroxyvitamin D3 [1,25-(OH)2D3], the biologically active metabolite of vitamin D3, inhibited synthesis of γ-interferon (IFN-γ) by phytohemagglutinin-activated peripheral blood lymphocytes (PBLs). A significant reduction of IFN-γ protein levels in PBL culture medium was achieved with a physiologic 1,25-(OH)2D3 concentration, 1,25-(OH)2D3 also inhibited accumulation of IFN-γ mRNA in activated PBLs in a dose-dependent fashion. The ability of 1,25-(OH)2D3 to modulate IFN-γ protein synthesis was unaltered in the presence of high concentrations of recombinant human interleukin 2. The suppression of IFN-γ synthesis by PBLs was specific for 1,25-(OH)2D3; the potencies of other vitamin D3 metabolites were correlated with their affinities for the cellular 1,25-(OH)2D3 receptor. The time course of 1,25-(OH)2D3 receptor expression in phytohemagglutinin-activated PBLs was correlated with the time course of 1,25-(OH)2D3-mediated inhibition of IFN-γ synthesis. Finally, the authors examined the effects of 1,25-(OH)2D3 on the constitutive IFN-γ production by two human T-lymphocyte lines transformed by human T-lymphotropic virus type I. The cell lines were established from a normal donor (cell line S-LB1) and from a patient with vitamin D-dependent rickets type 2 (cell line Ab-VDR). IFN-γ synthesis by S-LB1 cells was inhibited in a dose-dependent fashion by 1,25-(OH)2D3, whereas IFN-γ synthesis by Ab-VDR cells was not altered by 1,25-(OH)2D3. The data presented in this study provide evidence for a role of 1,25-(OH)2D3 in immunoregulation

  3. 1. cap alpha. ,25-Dihydroxyvitamin D/sub 3/ inhibits. gamma. -interferon synthesis by normal human peripheral blood lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Reichel, H.; Koeffler, H.P.; Tobler, A.; Norman, A.W.

    1987-05-01

    1..cap alpha..,25-Dihydroxyvitamin D/sub 3/ (1,25-(OH)/sub 2/D/sub 3/), the biologically active metabolite of vitamin D/sub 3/, inhibited synthesis of ..gamma..-interferon (IFN-..gamma..) by phytohemagglutinin-activated peripheral blood lymphocytes (PBLs). A significant reduction of IFN-..gamma.. protein levels in PBL culture medium was achieved with a physiologic 1,25-(OH)/sub 2/D/sub 3/ concentration, 1,25-(OH)/sub 2/D/sub 3/ also inhibited accumulation of IFN-..gamma.. mRNA in activated PBLs in a dose-dependent fashion. The ability of 1,25-(OH)/sub 2/D/sub 3/ to modulate IFN-..gamma.. protein synthesis was unaltered in the presence of high concentrations of recombinant human interleukin 2. The suppression of IFN-..gamma.. synthesis by PBLs was specific for 1,25-(OH)/sub 2/D/sub 3/; the potencies of other vitamin D/sub 3/ metabolites were correlated with their affinities for the cellular 1,25-(OH)/sub 2/D/sub 3/ receptor. The time course of 1,25-(OH)/sub 2/D/sub 3/ receptor expression in phytohemagglutinin-activated PBLs was correlated with the time course of 1,25-(OH)/sub 2/D/sub 3/-mediated inhibition of IFN-..gamma.. synthesis. Finally, the authors examined the effects of 1,25-(OH)/sub 2/D/sub 3/ on the constitutive IFN-..gamma.. production by two human T-lymphocyte lines transformed by human T-lymphotropic virus type I. The cell lines were established from a normal donor (cell line S-LB1) and from a patient with vitamin D-dependent rickets type 2 (cell line Ab-VDR). IFN-..gamma.. synthesis by S-LB1 cells was inhibited in a dose-dependent fashion by 1,25-(OH)/sub 2/D/sub 3/, whereas IFN-..gamma.. synthesis by Ab-VDR cells was not altered by 1,25-(OH)/sub 2/D/sub 3/. The data presented in this study provide evidence for a role of 1,25-(OH)/sub 2/D/sub 3/ in immunoregulation.

  4. Clusters of adaptive evolution in the human genome

    Directory of Open Access Journals (Sweden)

    Laura B. Scheinfeldt

    2011-09-01

    Full Text Available Considerable work has been devoted to identifying regions of the human genome that have been subjected to recent positive selection. Although detailed follow-up studies of putatively selected regions are critical for a deeper understanding of human evolutionary history, such studies have received comparably less attention. Recently, we have shown that ALMS1 has been the target of recent positive selection acting on standing variation in Eurasian populations. Here, we describe a careful follow-up analysis of genetic variation across the ALMS1 region, which unexpectedly revealed a cluster of substrates of positive selection. Specifically, through the analysis of SNP data from the HapMap and HGDP-CEPH samples as well sequence data from the region, we find compelling evidence for three independent and distinct signals of recent positive selection across this 3 Mb region surrounding ALMS1. Moreover, we analyzed the HapMap data to identify other putative clusters of independent selective events and conservatively discovered 19 additional clusters of adaptive evolution. This work has important implications for the interpretation of genome-scans for positive selection in humans and more broadly contributes to a better understanding of how recent positive selection has shaped genetic variation across the human genome.

  5. In-Vitro Carbofuran Induced Genotoxicity in Human Lymphocytes and Its Mitigation by Vitamins C and E

    Directory of Open Access Journals (Sweden)

    Ratnesh Kumar Sharma

    2012-01-01

    Full Text Available Various efforts have been made in past in order to predict the underlying mechanism of pesticide-induced toxicity using in vitro and animal models, however, these predictions may or may not be directly correlated with humans. The present study was designed to investigate the carbofuran induced genotoxicity and its amelioration by vitamins C and E by treating human peripheral blood lymphocytes (PBLs with different concentrations (0, 0.5, 1.25, 2.5, 3.75 and 5.0 μM of this compound. The treatment of PBLs with carbofuran displayed significant DNA damage in concentration dependent manner. The carbofuran induced genotoxicity could be ameliorated to considerable extent by pretreatment of PBLs with equimolar (10 μM concentration of each of the vitamins C and E; the magnitude of protection by vitamin E being higher than by vitamin C. Also, it was found that the level of protection by these vitamins was higher when PBLs were treated with lower concentrations of pesticide. The significant DNA damage as observed by H2O2, a positive control in the present study, and its amelioration by natural antioxidants (vitamins C and E lend an evidence to suggest that carbofuran would have caused genotoxicity via pesticide induced oxidative stress.

  6. In-vitro carbofuran induced genotoxicity in human lymphocytes and its mitigation by vitamins C and E.

    Science.gov (United States)

    Sharma, Ratnesh Kumar; Sharma, Bechan

    2012-01-01

    Various efforts have been made in past in order to predict the underlying mechanism of pesticide-induced toxicity using in vitro and animal models, however, these predictions may or may not be directly correlated with humans. The present study was designed to investigate the carbofuran induced genotoxicity and its amelioration by vitamins C and E by treating human peripheral blood lymphocytes (PBLs) with different concentrations (0, 0.5, 1.25, 2.5, 3.75 and 5.0 μM) of this compound. The treatment of PBLs with carbofuran displayed significant DNA damage in concentration dependent manner. The carbofuran induced genotoxicity could be ameliorated to considerable extent by pretreatment of PBLs with equimolar (10 μM) concentration of each of the vitamins C and E; the magnitude of protection by vitamin E being higher than by vitamin C. Also, it was found that the level of protection by these vitamins was higher when PBLs were treated with lower concentrations of pesticide. The significant DNA damage as observed by H_{2}O_{2}, a positive control in the present study, and its amelioration by natural antioxidants (vitamins C and E) lend an evidence to suggest that carbofuran would have caused genotoxicity via pesticide induced oxidative stress.

  7. Promising anticancer activity of a lichen, Parmelia sulcata Taylor, against breast cancer cell lines and genotoxic effect on human lymphocytes.

    Science.gov (United States)

    Ari, Ferda; Ulukaya, Engin; Oran, Seyhan; Celikler, Serap; Ozturk, Sule; Ozel, Mustafa Zafer

    2015-05-01

    Plants are still to be explored for new anti-cancer compounds because overall success in cancer treatment is still not satisfactory. As a new possible source for such compounds, the lichens are recently taking a great attention. We, therefore, explored both the genotoxic and anti-growth properties of lichen species Parmelia sulcata Taylor. The chemical composition of P. sulcata was analyzed with comprehensive gas chromatography-time of flight mass spectrometry. Anti-growth effect was tested in human breast cancer cell lines (MCF-7 and MDA-MB-231) by the MTT and ATP viability assays, while the genotoxic activity was studied by assays for micronucleus, chromosomal aberration and DNA fragmentation in human lymphocytes culture. Cell death modes (apoptosis/necrosis) were morphologically assessed. P. sulcata inhibited the growth in a dose-dependent manner up to a dose of 100 μg/ml and induced caspase-independent apoptosis. It also showed genotoxic activity at doses (>125 μg/ml) higher than that required for apoptosis. These results suggest that P. sulcata may induce caspase-independent apoptotic cell death at lower doses, while it may be genotoxic at relatively higher doses. PMID:24676908

  8. Resveratrol mobilizes endogenous copper in human peripheral lymphocytes leading to oxidative DNA breakage: a putative mechanism for chemoprevention of cancer.

    Science.gov (United States)

    Hadi, S M; Ullah, M F; Azmi, A S; Ahmad, A; Shamim, U; Zubair, H; Khan, H Y

    2010-06-01

    Plant polyphenols are important components of human diet, and a number of them are considered to possess chemopreventive and therapeutic properties against cancer. They are recognized as naturally occurring anti-oxidants but also act as pro-oxidants catalyzing DNA degradation in the presence of metal ions such as copper. The plant polyphenol resveratrol confers resistance to plants against fungal agents and has been implicated as a cancer chemopreventive agent. Of particular interest is the observation that resveratrol has been found to induce apoptosis in cancer cell lines but not in normal cells. Over the last few years, we have shown that resveratrol is capable of causing DNA breakage in cells such as human lymphocytes. Such cellular DNA breakage is inhibited by copper specific chelators but not by iron and zinc chelating agents. Similar results are obtained by using permeabilized cells or with isolated nuclei, indicating that chromatin-bound copper is mobilized in this reaction. It is well established that tissue, cellular and serum copper levels are considerably elevated in various malignancies. Therefore, cancer cells may be more subject to electron transfer between copper ions and resveratrol to generate reactive oxygen species responsible for DNA cleavage. The results are in support of our hypothesis that anti-cancer mechanism of plant polyphenols involves mobilization of endogenous copper and the consequent pro-oxidant action. Such a mechanism better explains the anti-cancer effects of resveratrol, as it accounts for the preferential cytotoxicity towards cancer cells.

  9. Differences in genotoxic activity of alpha-Ni3S2 on human lymphocytes from nickel-hypersensitized and nickel-unsensitized donors.

    Science.gov (United States)

    Arrouijal, F Z; Marzin, D; Hildebrand, H F; Pestel, J; Haguenoer, J M

    1992-05-01

    The genotoxic activity of alpha-Ni3S2 was assessed on human lymphocytes from nickel-hypersensitized (SSL) and nickel-unsensitized (USL) subjects. Three genotoxicity tests were performed: the sister chromatid exchange (SCE) test, the metaphase analysis test and the micronucleus test. (i) The SCE test (3-100 micrograms/ml) showed a weak but statistically significant increase in the number of SCE in both lymphocyte types with respect to controls, USL presenting a slightly higher SCE incidence but only at one concentration. (ii) The metaphase analysis test demonstrated a high dose-dependent clastogenic activity of alpha-Ni3S2 in both lymphocyte types. The frequency of chromosomal anomalies was significantly higher in USL than in SSL for all concentrations applied. (iii) The micronucleus test confirmed the dose-dependent clastogenic activity of alpha-Ni3S2 and the differences already observed between USL and SSL, i.e. the number of cells with micronuclei was statistically higher in USL. Finally, the incorporation study with alpha-63Ni3S2 showed a higher uptake of its solubilized fraction by USL. This allows an explanation of the different genotoxic action of nickel on the two cell types. In this study we demonstrated that hypersensitivity has an influence on the incorporation of alpha-Ni3S2 and subsequently on the different induction of chromosomal aberrations in human lymphocytes. PMID:1602972

  10. Radio-protective effect of cinnamic acid, a phenolic phytochemical, on genomic instability induced by X-rays in human blood lymphocytes in vitro.

    Science.gov (United States)

    Cinkilic, Nilufer; Tüzün, Ece; Çetintaş, Sibel Kahraman; Vatan, Özgür; Yılmaz, Dilek; Çavaş, Tolga; Tunç, Sema; Özkan, Lütfi; Bilaloğlu, Rahmi

    2014-08-01

    The present study was designed to determine the protective activity of cinnamic acid against induction by X-rays of genomic instability in normal human blood lymphocytes. This radio-protective activity was assessed by use of the cytokinesis-block micronucleus test and the alkaline comet assay, with human blood lymphocytes isolated from two healthy donors. A Siemens Mevatron MD2 (Siemens AG, USA, 1994) linear accelerator was used for the irradiation with 1 or 2 Gy. Treatment of the lymphocytes with cinnamic acid prior to irradiation reduced the number of micronuclei when compared with that in control samples. Treatment with cinnamic acid without irradiation did not increase the number of micronuclei and did not show a cytostatic effect in the lymphocytes. The results of the alkaline comet assay revealed that cinnamic acid reduces the DNA damage induced by X-rays, showing a significant radio-protective effect. Cinnamic acid decreased the frequency of irradiation-induced micronuclei by 16-55% and reduced DNA breakage by 17-50%, as determined by the alkaline comet assay. Cinnamic acid may thus act as a radio-protective compound, and future studies may focus on elucidating the mechanism by which cinnamic acid offers radioprotection.

  11. Selective destruction of mouse islet beta cells by human T lymphocytes in a newly-established humanized type 1 diabetic model

    International Nuclear Information System (INIS)

    Research highlights: → Establish a human immune-mediated type 1 diabetic model in NOD-scid IL2rγnull mice. → Using the irradiated diabetic NOD mouse spleen mononuclear cells as trigger. → The islet β cells were selectively destroyed by infiltrated human T cells. → The model can facilitate translational research to find a cure for type 1 diabetes. -- Abstract: Type 1 diabetes (T1D) is caused by a T cell-mediated autoimmune response that leads to the loss of insulin-producing β cells. The optimal preclinical testing of promising therapies would be aided by a humanized immune-mediated T1D model. We develop this model in NOD-scid IL2rγnull mice. The selective destruction of pancreatic islet β cells was mediated by human T lymphocytes after an initial trigger was supplied by the injection of irradiated spleen mononuclear cells (SMC) from diabetic nonobese diabetic (NOD) mice. This resulted in severe insulitis, a marked loss of total β-cell mass, and other related phenotypes of T1D. The migration of human T cells to pancreatic islets was controlled by the β cell-produced highly conserved chemokine stromal cell-derived factor 1 (SDF-1) and its receptor C-X-C chemokine receptor (CXCR) 4, as demonstrated by in vivo blocking experiments using antibody to CXCR4. The specificity of humanized T cell-mediated immune responses against islet β cells was generated by the local inflammatory microenvironment in pancreatic islets including human CD4+ T cell infiltration and clonal expansion, and the mouse islet β-cell-derived CD1d-mediated human iNKT activation. The selective destruction of mouse islet β cells by a human T cell-mediated immune response in this humanized T1D model can mimic those observed in T1D patients. This model can provide a valuable tool for translational research into T1D.

  12. Selective Elimination of Human Regulatory T Lymphocytes In Vitro With the Recombinant Immunotoxin LMB-2

    OpenAIRE

    Attia, Peter; Daniel J Powell; Maker, Ajay V; Kreitman, Robert J.; Pastan, Ira; Rosenberg, Steven A.

    2006-01-01

    CD4+CD25+ T-regulatory cells (Treg) can inhibit the proliferation and cytokine secretion of CD4+CD25− helper T cells in mice and humans. In murine tumor models, the presence of these Treg cells can inhibit the antitumor effectiveness of T-cell transfer and active immunization approaches. We have thus initiated efforts to eliminate Treg cells selectively from human peripheral blood mononuclear cells (PBMCs) to potentially bolster antitumor responses. LMB-2 is a recombinant immunotoxin that is ...

  13. Ontogeny of Innate T Lymphocytes – Some Innate Lymphocytes are More Innate than Others

    OpenAIRE

    Vermijlen, David; Prinz, Immo

    2014-01-01

    Innate lymphocytes have recently received a lot of attention. However, there are different ideas about the definition of what is “innate” in lymphocytes. Lymphocytes without V(D)J-rearranged antigen receptors are now termed innate lymphoid cells (ILCs) and include cells formerly known as natural killer (NK) cells. Also, lymphocytes that are innate should be able to recognize microbial or stress-induced patterns and react rapidly without prior sensitization, as opposed to adaptive immune respo...

  14. Ontogeny of innate T lymphocytes - some innate lymphocytes are more innate then others

    OpenAIRE

    David eVermijlen; Immo ePrinz

    2014-01-01

    Innate lymphocytes have recently received a lot of attention. However, there are different ideas about the definition of what is innate in lymphocytes. Lymphocytes without V(D)J-rearranged antigen receptors are now termed innate lymphoid cells (ILCs) and include cells formerly known as NK cells. Also, lymphocytes that are innate should be able to recognize microbial or stress-induced patterns and react rapidly without prior sensitization, as opposed to adaptive immune responses. Formally, gen...

  15. The specificity of stimulus-specific adaptation in human auditory cortex increases with repeated exposure to the adapting stimulus.

    Science.gov (United States)

    Briley, Paul M; Krumbholz, Katrin

    2013-12-01

    The neural response to a sensory stimulus tends to be more strongly reduced when the stimulus is preceded by the same, rather than a different, stimulus. This stimulus-specific adaptation (SSA) is ubiquitous across the senses. In hearing, SSA has been suggested to play a role in change detection as indexed by the mismatch negativity. This study sought to test whether SSA, measured in human auditory cortex, is caused by neural fatigue (reduction in neural responsiveness) or by sharpening of neural tuning to the adapting stimulus. For that, we measured event-related cortical potentials to pairs of pure tones with varying frequency separation and stimulus onset asynchrony (SOA). This enabled us to examine the relationship between the degree of specificity of adaptation as a function of frequency separation and the rate of decay of adaptation with increasing SOA. Using simulations of tonotopic neuron populations, we demonstrate that the fatigue model predicts independence of adaptation specificity and decay rate, whereas the sharpening model predicts interdependence. The data showed independence and thus supported the fatigue model. In a second experiment, we measured adaptation specificity after multiple presentations of the adapting stimulus. The multiple adapters produced more adaptation overall, but the effect was more specific to the adapting frequency. Within the context of the fatigue model, the observed increase in adaptation specificity could be explained by assuming a 2.5-fold increase in neural frequency selectivity. We discuss possible bottom-up and top-down mechanisms of this effect.

  16. Expression of Growth Hormone Receptors by Lymphocyte subpopulations in the Human tonsil

    OpenAIRE

    Olivier Thellin; Bernard Coumans; Willy Zorzi; Ross Barnard; Georges Hennen; Ernst Heinen; Ahmed Igout

    1998-01-01

    The ability of human tonsillar lymphoid cells to express growth hormone receptor (hGH-N-R) was analyzed by flow cytometry. FITC-coupled recombinant human growth hormone (hGH-N) was used to reveal the receptors, in combination with phenotype markers. Unlike T cells, tonsillar B cells constitutively express the hGH-N receptor. Quiescent cells separated from activated cells by Percoll-gradient centrifugation bear fewer receptors than activated ones. Activated T cells express hGH-N-R, but the typ...

  17. Adaptive image contrast enhancement based on human visual properties

    International Nuclear Information System (INIS)

    Existing methods for image contrast enhancement focus mainly on the properties of the image to be processed while excluding any consideration of the observer characteristics. In several applications, particularly in the medical imaging area, effective contrast enhancement for diagnostic purposes can be achieved by including certain basic human visual properties. In this paper the authors present a novel adaptive algorithm that tailors the required amount of contrast enhancement based on the local contrast of the image and the observer's Just-Noticeable-Difference (JND). This algorithm always produces adequate contrast in the output image, and results in almost no ringing artifacts even around sharp transition regions, which is often seen in images processed by conventional contrast enhancement techniques. By separating smooth and detail areas of an image and considering the dependence of noise visibility on the spatial activity of the image, the algorithm treats them differently and thus avoids excessive enhancement of noise, which is another common problem for many existing contrast enhancement techniques. The present JND-Guided Adaptive Contrast Enhancement (JGACE) technique is very general and can be applied to a variety of images. In particular, it offers considerable benefits in digital radiography applications where the objective is to increase the diagnostic utility of images. A detailed performance evaluation together with a comparison with the existing techniques is given to demonstrate the strong features of JGACE

  18. Recombinant human B7-H4 expressed in Escherichia coli inhibits T lymphocyte proliferation and IL-2 secretion in vitro

    Institute of Scientific and Technical Information of China (English)

    Yi-xiang MAO; Xue-guang ZHANG; Yong-Jing CHEN; Van GE; Hong-bing MA; Jian-feng YU; Hong-ya WU; Yu-min HU; Qin WANG; Qin SHI

    2006-01-01

    Aim: To explore the biofunctions of human B7-H4 generated from prokaryotic system. Methods: The gene of human B7-H4 extracellular region (IgⅤ-like and IgC-like domains) was obtained by PCR from human cDNA FLJ22418 and then inserted into the prokaryotic expression vector pGEX-5X-3 expressing glutathione. r-transferase (GST) fusion protein. After being identified by restriction enzyme digestion and sequencing, the recombinant vector was transferred into host strain E coli BL21-RIL(DE3). A 47 kDa fusion protein (GST/hB7-H4) was induced by isopropyl-beta-D-thiogalactopyranoside (IPTG) and purified by standard methods reported in the prokaryotic system. The inhibitory effect of GST/hB7-H4 on proliferation of T cells was observed in vitro by CD3mAb activated T-cell cultur-ing system and [3H]-thymidine incorporation assay. The concentrations of interleukin-2 and iterferon-g in the supernatants of T cells were determined by ELISA. Results: We successfully constructed the method for high-level expression and purification of the hB7-H4 extracellular domain as GST fusion protein from E coli. The GST/hB7-H4 fusion protein produced in bacteria had obvious biological activity to inhibit T-lymphocyte proliferation and IL-2 secretion. Conclusion: The prokaryote expression system could be used to generate hB7-H4 protein with natural spatial conformations and biological functions, which provided an efficient and economical way for the preparation of this target protein.

  19. The origins of music as an adaptive trait in humans

    Directory of Open Access Journals (Sweden)

    Amodeo, Martín Raúl

    2014-04-01

    Full Text Available Throughout human history, people have developed the faculty to appreciate and create music. Musical thinking implies the development of cognitive and emotional faculties by complex neural processes. How could such a complex behavior as music be originated by evolution? This article reviews the main evolutionary approaches that have been proposed to explain this process. The main hypotheses state that music has emerged from adaptive processes such as communication and emotional coordination between mother and infant, the conformation of large cohesive groups, mate selection or the development of cognitive and emotional flexibility through play. Natural selection could have enabled the establishment of this faculty, whereas cultural evolution and gene-culture interaction could have led to the establishment of music as we know it.

  20. Clofazimine inhibits human Kv1.3 potassium channel by perturbing calcium oscillation in T lymphocytes.

    Directory of Open Access Journals (Sweden)

    Yunzhao R Ren

    Full Text Available The Kv1.3 potassium channel plays an essential role in effector memory T cells and has been implicated in several important autoimmune diseases including multiple sclerosis, psoriasis and type 1 diabetes. A number of potent small molecule inhibitors of Kv1.3 channel have been reported, some of which were found to be effective in various animal models of autoimmune diseases. We report herein the identification of clofazimine, a known anti-mycobacterial drug, as a novel inhibitor of human Kv1.3. Clofazimine was initially identified as an inhibitor of intracellular T cell receptor-mediated signaling leading to the transcriptional activation of human interleukin-2 gene in T cells from a screen of the Johns Hopkins Drug Library. A systematic mechanistic deconvolution revealed that clofazimine selectively blocked the Kv1.3 channel activity, perturbing the oscillation frequency of the calcium-release activated calcium channel, which in turn led to the inhibition of the calcineurin-NFAT signaling pathway. These effects of clofazimine provide the first line of experimental evidence in support of a causal relationship between Kv1.3 and calcium oscillation in human T cells. Furthermore, clofazimine was found to be effective in blocking human T cell-mediated skin graft rejection in an animal model in vivo. Together, these results suggest that clofazimine is a promising immunomodulatory drug candidate for treating a variety of autoimmune disorders.

  1. Improvement of lymphocyte proliferation in human immunodeficiency virus infection after recombinant interleukin-2 treatment

    DEFF Research Database (Denmark)

    Afzelius, P; Nielsen, S D; Nielsen, Jens Ole;

    1999-01-01

    In this study, the effect of recombinant interleukin-2 (rIL-2) on the function of peripheral blood mononuclear cells (PBMC) from human immunodeficiency virus (HIV)-infected patients was examined. Using polymerase chain reaction (PCR), an impaired ability of PBMC from 8 patients to respond upon...

  2. Inhibition of human lymphocyte proliferative response by serum from Plasmodium falciparum infected patients

    DEFF Research Database (Denmark)

    Theander, T G; Svenson, M; Bygbjerg, I C;

    1987-01-01

    Malaria infection has been shown to induce alterations in immune reactivity. This report describes the effect of serum obtained from Plasmodium falciparum infected patients on in vitro proliferation of human blood mononuclear cells (BMNC) isolated from healthy individuals. Serum obtained before...

  3. Improvement of lymphocyte proliferation in human immunodeficiency virus infection after recombinant interleukin-2 treatment

    DEFF Research Database (Denmark)

    Afzelius, P; Nielsen, S D; Nielsen, Jens Ole;

    1999-01-01

    In this study, the effect of recombinant interleukin-2 (rIL-2) on the function of peripheral blood mononuclear cells (PBMC) from human immunodeficiency virus (HIV)-infected patients was examined. Using polymerase chain reaction (PCR), an impaired ability of PBMC from 8 patients to respond upon mi...

  4. Ketamine induces apoptosis via the mitochondrial pathway in human lymphocytes and neuronal cells

    NARCIS (Netherlands)

    S. Braun; N. Gaza; R. Werdehausen; H. Hermanns; I. Bauer; M.E. Durieux; M.W. Hollmann; M.F. Stevens

    2010-01-01

    BACKGROUND: Ketamine has been shown to have neurotoxic properties, when administered neuraxially. The mechanism of this local toxicity is still unknown. Therefore, we investigated the mechanism of cytotoxicity in different human cell lines in vitro. METHODS: We incubated the following cell types for

  5. The Biological Effectiveness of Four Energies of Neon Ions for the Induction of Chromosome Damage in Human Lymphocytes

    Science.gov (United States)

    George, Kerry; Hada, Megumi; Cucinotta, F. A.

    2011-01-01

    Chromosomal aberrations were measured in human peripheral blood lymphocytes after in vitro exposure to neon ions at energies of 64, 89, 142, or 267. The corresponding LET values for these energies of neon ranged from 38-103 keV/micrometers and doses delivered were in the 10 to 80 cGy range. Chromosome exchanges were assessed in metaphase and G2 phase cells at first division after exposure using fluorescence in situ hybridization (FISH) with whole chromosome probes and dose response curves were generated for different types of chromosomal exchanges. The yields of total chromosome exchanges were similar for the 64, 89, and 142 MeV exposures, whereas the 267 MeV/u neon with LET of 38 keV/micrometers produced about half as many exchanges per unit dose. The induction of complex type chromosome exchanges (exchanges involving three or more breaks and two or more chromosomes) showed a clear LET dependence for all energies. The ratio of simple to complex type exchanges increased with LET from 18 to 51%. The relative biological effectiveness (RBE) was estimated from the initial slope of the dose response curve for chromosome damage with respect to gamma-rays. The RBE(sub max) values for total chromosome exchanges for the 64 MeV/u was around 30.

  6. Use of γ-H2AX Foci Assay on Human Peripheral Blood Lymphocytes as Sensitive Biomarker of Exposure

    International Nuclear Information System (INIS)

    In modern medicine, it is impossible to imagine diagnostics and treatments without equipment that emit radiation (X-ray, CT, PET, etc.). At the same time there is a need to minimize the amount of radiation that the patient will gain during such medical examination. In that manner ALARA (As Low As Reasonably Achievable) principle and dosimetry are the bases of assuring patients safety. The induction of gamma phosphorylated H2AX histone is newly developed tool in biodosimetry, which is more sensitive for the detection of radiation caused DNA damage than currently used micronucleus and comet assay. Gamma phosphorylation of H2AX histone is a consequence of DNA double strand breaks and its role is to trigger the DNA repair mechanisms. In this study, we tested the effect of 2 and 4 Gy X-rays on human peripheral blood lymphocytes from two healthy volunteers using γ-H2AX foci assay. The FITC signal from labelled antibodies was monitored using flow cytometry and clearly demonstrated the difference in control samples and irradiated samples. There was also the difference between the exposed blood samples from the two volunteers. The results of present study reveal new sensitive method that is capable of detecting changes in DNA when exposed to different doses of radiation, and thus potentially optimizing the ALARA principle.(author)

  7. Dose Response for Chromosome Aberrations in Human Lymphocytes and Fibroblasts after Exposure to Very Low Doses of High LET Radiation

    Science.gov (United States)

    Hada, M.; George, Kerry; Cucinotta, Francis A.

    2011-01-01

    The relationship between biological effects and low doses of absorbed radiation is still uncertain, especially for high LET radiation exposure. Estimates of risks from low-dose and low-dose-rates are often extrapolated using data from Japanese atomic bomb survivors with either linear or linear quadratic models of fit. In this study, chromosome aberrations were measured in human peripheral blood lymphocytes and normal skin fibroblasts cells after exposure to very low dose (1-20 cGy) of 170 MeV/u Si-28- ions or 600 MeV/u Fe-56-ions. Chromosomes were analyzed using the whole chromosome fluorescence in situ hybridization (FISH) technique during the first cell division after irradiation, and chromosome aberrations were identified as either simple exchanges (translocations and dicentrics) or complex exchanges (involving greater than 2 breaks in 2 or more chromosomes). The curves for doses above 10 cGy were fitted with linear or linear-quadratic functions. For Si-28- ions no dose response was observed in the 2-10 cGy dose range, suggesting a non-target effect in this range.

  8. Comparison of effects of six tritiated compounds on chromosomal aberrations in human lymphocytes in vitro and dose-response relationships

    International Nuclear Information System (INIS)

    The effects of six tritiated compounds on chromosomal aberrations were compared in cultured human lymphocytes, and dose-response relationships were analysed. According to the efficiency of inducing aberrations, these compounds could be arranged in decreasing order as follows: 3H-TdR > 3H-UdR > 3H-lysine > 3H-thymine > 3H-leucine > HTO, when the dose-response relationship was expressed in radioactivity/ml of the medium. This order is determined mainly by the radioactivities incorporated into the nuclei or the cells. However, when compared in terms of the dose absorbed by the nuclei or the cells, the differences among various compounds would be much more reduced. The data of aberration yields for different tritium activities (or absorbed dsoes) were fitted satisfactorily to the linear-quadratic dose-response equation Y = A + BX + CX2. The yields of chromatid-type and chromosometype aberrations induced by various tritiated compounds were quite different. These differences are related to the metabolism of the compounds

  9. Drinking-Water Arsenic Exposure Modulates Gene Expression in Human Lymphocytes from a U.S. Population

    Science.gov (United States)

    Andrew, Angeline S.; Jewell, David A.; Mason, Rebecca A.; Whitfield, Michael L.; Moore, Jason H.; Karagas, Margaret R.

    2008-01-01

    Background Arsenic exposure impairs development and can lead to cancer, cardiovascular disease, and diabetes. The mechanism underlying these effects remains unknown. Primarily because of geologic sources of contamination, drinking-water arsenic levels are above the current recommended maximum contaminant level of 10 μg/L in the northeastern, western, and north central regions of the United States. Objectives We investigated the effects of arsenic exposure, defined by internal biomarkers at levels relevant to the United States and similarly exposed populations, on gene expression. Methods We conducted separate Affymetrix microarray-based genomewide analyses of expression patterns. Peripheral blood lymphocyte samples from 21 controls interviewed (1999–2002) as part of a case–control study in New Hampshire were selected based on high- versus low-level arsenic exposure levels. Results The biologic functions of the transcripts that showed statistically significant abundance differences between high- and low-arsenic exposure groups included an overrepresentation of genes involved in defense response, immune function, cell growth, apoptosis, regulation of cell cycle, T-cell receptor signaling pathway, and diabetes. Notably, the high-arsenic exposure group exhibited higher levels of several killer cell immunoglobulin-like receptors that inhibit natural killer cell activity. Conclusions These findings define biologic changes that occur with chronic arsenic exposure in humans and provide leads and potential targets for understanding and monitoring the pathogenesis of arsenic-induced diseases. PMID:18414638

  10. Relationship between osteosarcoma and ionizing radiation hypersensitive human B lymphocyte cells lacking RecQL4 helicase

    International Nuclear Information System (INIS)

    Japanese society is now facing a transition period from aging society to super aging society. Concomitant with this situation, it is estimated that number of cancer patients and the requirement of less invasive Radiation Therapy (RT) for cancers will increase. Therefore, understanding of mechanisms without delay on second cancers caused by RT is indispensable. Osteosarcoma, an aggressive bone tumor frequently occurring 5% of cancers in young adult and children, increase statistically after RT for cancers. Although, mutation in p53, Rb and RecQL4 genes statistically relate with osteosarcoma incidence, precise mechanisms of osteosarcoma development by ionizing Radiation (IR) remain to be elucidated. Genome instability is one of the tumor promoting factors and we focused on RecQL4 in RecQ helicase family, which is involved in aging and cancer. We established RecQL4 knock-in human B lymphocyte Nalm-6 cells and found their hypersensitivity to IR, replication fork stall/collapses after IR. In this review, we summarize recently published studies on genetic cancer-predisposing syndrome and possible origins of bone cancers induced by IR. Then, we discuss what and how we address molecular mechanisms on osteosarcoma induced by IR in the future. (author)

  11. Radiographic resolution of lymphocytic interstitial pneumonitis (LIP) in children with human immunodeficiency virus (HIV): not a sign of clinical deterioration

    Energy Technology Data Exchange (ETDEWEB)

    Lynch, J.L.; Blickman, J.G.; TerMeulen, D.C. [Dept. of Radiology, Boston Medical Center, Boston University School of Medicine, Boston, MA (United States); Babl, F.E. [Div. of Pediatric Infections Diseases, Boston Medical Center, MA (United States); Dept. of Pediatrics, Boston Univ. School of Medicine, Boston, MA (United States); Moloney, C.H.; Pelton, S.I. [Dept. of Pediatrics, Boston Univ. School of Medicine, Boston, MA (United States)

    2001-04-01

    Background. The literature and anecdotal evidence associate the resolution of radiographic findings of lymphocytic interstitial pneumonitis (LIP) with a decline in immune and clinical status of human immunodeficiency virus (HIV) infected children. Objective. As our clinical impression was the opposite, we sought to elucidate this contradiction. Materials and methods. Of 52 pediatric patients infected with the HIV currently being followed at our institution, 20 (38.5 %) carried the diagnosis of LIP and 13 (65 %) of these have had complete resolution of radiographic findings of LIP. We retrospectively reviewed the chest radiographs, CD4 counts, and clinical history of these 13 patients. Results. Of the 13 patients who had resolution of radiographic findings, 11 (84.6 %) had no significant change in CD4 count at the time of resolution and remained clinically stable during a mean follow-up period of 32 months. Two patients (15.3 %) developed severe CD4 lymphocytopenia at the time of resolution of LIP, but clinically remained stable. None of these 13 patients had a recurrence of LIP, even with subsequent increases in CD4 count. Conclusion. We suggest that in contradiction to previously published data, resolution of LIP on chest radiographs is not an indicator for poor prognosis for the HIV-infected pediatric patient. (orig.)

  12. Lack of genotoxic effects (micronucleus induction) in human lymphocytes exposed in vitro to 900 MHz electromagnetic fields.

    Science.gov (United States)

    Zeni, O; Chiavoni, A S; Sannino, A; Antolini, A; Forigo, D; Bersani, F; Scarfì, M R

    2003-08-01

    In the present study, we investigated the induction of genotoxic effects in human peripheral blood lymphocytes after exposure to electromagnetic fields used in mobile communication systems (frequency 900 MHz). For this purpose, the incidence of micronuclei was evaluated by applying the cytokinesis-block micronucleus assay. Cytotoxicity was also investigated using the cytokinesis-block proliferation index. The experiments were performed on peripheral blood from 20 healthy donors, and several conditions were tested by varying the duration of exposure, the specific absorption rate (SAR), and the signal [continuous-wave (CW) or GSM (Global System of Mobile Communication) modulated signal]. The following exposures were carried out: (1) CW intermittent exposure (SAR = 1.6 W/kg) for 6 min followed by a 3-h pause (14 on/off cycles); (2) GSM signal, intermittent exposure as described in (1); (3) GSM signal, intermittent exposure as described in (1) 24 h before stimulation with phytohemagglutinin (8 on/off cycles); (4) GSM signal, intermittent exposure (SAR = 0.2 W/kg) 1 h per day for 3 days. The SARs were estimated numerically. No statistically significant differences were detected in any case in terms of either micronucleus frequency or cell cycle kinetics.

  13. Anti-genotoxic effect of naringin against bleomycin-induced genomic damage in human lymphocytes in vitro.

    Science.gov (United States)

    Yilmaz, Dilek; Teksoy, Ozgun; Bilaloglu, Rahmi; Çinkilic, Nilufer

    2016-01-01

    Naringin is a flavonoid found in grapefruit and other citrus fruits that shows antioxidant activity. The aim of the present study was to determine the anti-genotoxic and protective effects of naringin on the chemotherapeutic/radiomimetic agent bleomycin (BLM) in human blood lymphocyte cultures in vitro using micronucleus test and chromosomal aberrations (CA) assay. We tested the three doses of naringin (1, 2, 3 µg/mL) and a single dose of BLM (20 µg/mL). BLM significantly increased the total CAs and micronucleus frequency at a concentration of 20 µg/mL. Naringin did not show any toxicity in doses of 1, 2, and 3 µg/mL. Combined treatments of BLM and naringin (2 and 3 µg/mL) significantly reduced micronucleus formation. Naringin dose-dependently decreased the total chromosome aberrations frequency induced by BLM. These results indicate that naringin could prevent BLM (20 µg/mL)-induced genotoxicity. PMID:25941869

  14. The effects of biological and life-style factors on baseline frequencies of chromosome aberrations in human lymphocytes

    Directory of Open Access Journals (Sweden)

    Hilada Nefic

    2014-01-01

    Full Text Available Objective: This study investigated the influence of sex and ageing on chromosomal damage and the role of life-style habits on the frequency of chromosomal aberrations (CAs in peripheral blood lymphocytes (PBLs of healthy Bosnian subjects. Materials and Methods: Peripheral blood samples were obtained from 100 healthy, unrelated individuals in Bosnia and Herzegovina during 2010 and 2011. Chromosome preparations were made by dropping and air drying and slides were stained with 10% Giemsa solution (pH 6.8. The cytogenetic analysis was carried out in a cytogenetic laboratory in the Department of Biology of the Faculty of Science in Sarajevo. The category of total structural CAs was sub classified as chromosome-type aberrations (CSAs and chromatid-type aberrations (CTAs while the category of total numerical CAs was sub classified as aneuploid and polyploid mitoses. All statistical analyses were carried out using Microsoft Excel 2010 (Microsoft Corporation and the Windows Kwikstat Winks SDA 7.0.2 statistical software package (Texa Soft Cedar Hill, Texas. Results: Cytogenetic analysis revealed the average number of structural CAs was 2.84 and of numerical CAs was 9.56. There was a significant increase in the frequency of chromosome-type aberrations (1.92 compared with chromatid-type aberrations (CTAs (0.92 and a significant increase in the frequency of aneuploid (8.83 compared with polyploid (0.73 mitoses. Significant positive correlations between age and CTAs in human PBLs were also demonstrated. Additional statistical analysis showed that ageing increase number of numerical CAs in lymphocytes of drinkers. The frequency of structural CAs of females exposed to radiation was significantly greater than in males. Analysis indicates the presence of a positive association between CAs and smoking in younger subjects but a negative correlation between aberrant cells frequencies and alcohol in older drinkers. Conclusion: The results of the study support the

  15. Chlamydia pneumoniae Inhibits Activated Human T Lymphocyte Proliferation by the Induction of Apoptotic and Pyroptotic Pathways

    OpenAIRE

    Olivares-Zavaleta, Norma; Carmody, Aaron; Messer, Ronald; Whitmire, William M.; Caldwell, Harlan D.

    2011-01-01

    Chlamydia pneumoniae is an omnipresent obligate intracellular bacterial pathogen that infects numerous host species. C. pneumoniae infections of humans are a common cause of community acquired pneumonia but have also been linked to chronic diseases such as atherosclerosis, Alzheimer’s disease, and asthma. Persistent infection and immune avoidance are believed to play important roles in the pathophysiology of C. pneumoniae disease. We found that C. pneumoniae organisms inhibited activated but ...

  16. Heterogeneity of clones from a human metastatic melanoma detected by autologous cytotoxic T lymphocyte clones

    OpenAIRE

    1986-01-01

    The possibility that a single human tumor may be composed of an heterogeneous population of cells with respect to susceptibility to lysis by autologous CTL clones was investigated by testing six cytolytic clones derived by micromanipulation against the autologous metastatic melanoma, Me28, and against 31 clones derived from Me28 by cloning in soft agar. Highly significant differences in the lysis of many tumor clones were observed by three of the CTL effectors in comparison with the cytotoxic...

  17. Different subtypes of GABA-A receptors are expressed in human, mouse and rat T lymphocytes.

    Directory of Open Access Journals (Sweden)

    Suresh K Mendu

    Full Text Available γ-Aminobutyric acid (GABA is the most prominent neuroinhibitory transmitter in the brain, where it activates neuronal GABA-A receptors (GABA-A channels located at synapses and outside of synapses. The GABA-A receptors are primary targets of many clinically useful drugs. In recent years, GABA has been shown to act as an immunomodulatory molecule. We have examined in human, mouse and rat CD4(+ and CD8(+ T cells which subunit isoforms of the GABA-A channels are expressed. The channel physiology and drug specificity is dictated by the GABA-A receptor subtype, which in turn is determined by the subunit isoforms that make the channel. There were 5, 8 and 13 different GABA-A subunit isoforms identified in human, mouse and rat CD4(+ and CD8(+ T cells, respectively. Importantly, the γ2 subunit that imposes benzodiazepine sensitivity on the GABA-A receptors, was only detected in the mouse T cells. Immunoblots and immunocytochemistry showed abundant GABA-A channel proteins in the T cells from all three species. GABA-activated whole-cell transient and tonic currents were recorded. The currents were inhibited by picrotoxin, SR95531 and bicuculline, antagonists of GABA-A channels. Clearly, in both humans and rodents T cells, functional GABA-A channels are expressed but the subtypes vary. It is important to bear in mind the interspecies difference when selecting the appropriate animal models to study the physiological role and pharmacological properties of GABA-A channels in CD4(+ and CD8(+ T cells and when selecting drugs aimed at modulating the human T cells function.

  18. Differential Micronuclei Induction in Human Lymphocyte Cultures by Imidacloprid in the Presence of Potassium Nitrate

    OpenAIRE

    Polychronis Stivaktakis; Dimitris Vlastos; Evangelos Giannakopoulos; Matthopoulos, Demetrious P.

    2010-01-01

    Humans are exposed to pesticides as a consequence of their application in farming or their persistence in a variety of media, including food, water, air, soil, plants, animals, and smoke. The interaction of pesticides with environmental factors may result in the alteration of their physicochemical properties. Square wave cathodic stripping voltammetry (SW-CSV), a technique that simulates electrodynamically the cellular membrane, is used to investigate whether the presence of potassium nitrate...

  19. In vitro effect of chloroquine, mefloquine and quinine on human lymphocyte proliferative responses to malaria antigens and other antigens/mitogens

    DEFF Research Database (Denmark)

    Bygbjerg, I C; Theander, T G; Andersen, B J;

    1986-01-01

    The effect of 3 antimalarial quinoline derivatives, chloroquine, mefloquine and quinine on human blood mononuclear cells in vitro was studied. High concentrations profoundly suppressed the proliferation of mitogen- and antigen-stimulated lymphocytes, as indicated by decreased 14C-thymidine incorp......The effect of 3 antimalarial quinoline derivatives, chloroquine, mefloquine and quinine on human blood mononuclear cells in vitro was studied. High concentrations profoundly suppressed the proliferation of mitogen- and antigen-stimulated lymphocytes, as indicated by decreased 14C......-thymidine incorporation. On a weight base, the most potent drug was mefloquine. At clinically relevant doses, chloroquine and mefloquine did not affect the response to malaria antigens, but mefloquine decreased the response to phytohaemagglutinin; quinine suppressed the response to all mitogens (with the exception...

  20. The Regularities of the Induction and Reparation of DNA Double Strand Breaks in Human Lymphocytes after Irradiation by Carbon Ions with High Energy

    CERN Document Server

    Boreyko, A V

    2005-01-01

    The regularities of the induction of DNA double strand breaks (DSB) in human lymphocytes after irradiation by different doses of accelerated carbon ions (480 MeV/nucleon, LET = 10.6 keV/$\\mu $m) and $\\gamma $-rays $^{60}$?? by using of comet assay were investigated. It was shown that dependence of DSB formation increases linearly with growing of the dose of carbon ions and $\\gamma $-rays. The biological effectiveness of carbon ions with high energy was similar to $\\gamma $-rays. The kinetics of DSB reparation in human lymphocytes after irradiation by both carbon ions and $\\gamma $-rays was studied. It is revealed that the reparation proceeds effectively with heavy ion and $\\gamma $-ray irradiation.

  1. The regularities of the induction and reparation of DNA double strand breaks in human lymphocytes after irradiation by carbon ions with high energy

    International Nuclear Information System (INIS)

    The regularities of the induction of DNA double strand breaks (DSB) in human lymphocytes after irradiation by different doses of accelerated carbon ions (480 MeV/nucleon, LET = 10.6 keV/μm) and γ-rays 60Co by using of comet assay were investigated. It was shown that dependence of DSB formation increases linearly with growing of the dose of carbon ions and γ-rays. The biological effectiveness of carbon ions with high energy was similar to γ-rays. The kinetics of DSB reparation in human lymphocytes after irradiation by both carbon ions and γ-rays was studied. It is revealed that the reparation proceeds effectively with heavy ions and γ-ray irradiation

  2. Inhibition of Pro-oxidant induced DNA Damage in isolated human peripheral lymphocytes by methanolic extract of Guduchi (Tinospora cordifolia) leaves.

    OpenAIRE

    Chandrashekar S; Umesha S,; Chethan Kumar M,; Chandan S

    2010-01-01

    The present preliminary investigation reveals the anti-oxidant effects of Guduchi (Tinospora cordifolia) leaves. Dried and powdered leaves of Tinospora cordifolia was subjected to methanol extraction, and total phenols, sugars and proteins were determined. DNA fragmentation was carried out using isolated human peripheral lymphocytes and Calf thymus DNA as a model system. The results showed that the methanol extract of Tinospora cordifolia is rich in total polyphenols (>3 mg/g) in comparison t...

  3. A novel mode of human immunodeficiency virus type 1 (HIV-1) activation: ligation of CD28 alone induces HIV-1 replication in naturally infected lymphocytes.

    OpenAIRE

    1993-01-01

    Induction of human immunodeficiency virus (HIV) replication in infected CD4+ T lymphocytes requires cellular activation. The ligation of CD28, a signal-transducing receptor with a natural ligand on activated B cells and antigen-presenting cells, provides a costimulating signal for interleukin 2 production and T-cell proliferation as well as coactivation of the transfected HIV long terminal repeat in Jurkat cells. The aim of the present study was to investigate the ability of CD28 ligation to ...

  4. Constitutive expression of genes encoding notch receptors and ligands in developing lymphocytes, nTreg cells and dendritic cells in the human thymus.

    Science.gov (United States)

    Bento-de-Souza, Luciana; Victor, Jefferson R; Bento-de-Souza, Luiz C; Arrais-Santos, Magaly; Rangel-Santos, Andréia C; Pereira-Costa, Érica; Raniero-Fernandes, Elaine; Seixas-Duarte, Maria I; Oliveira-Filho, João B; Silva Duarte, Alberto J

    2016-01-01

    The thymus is the site of T cell maturation. Notch receptors (Notch1-4) and ligands (DLL1-3 and Jagged1-2) constitute one of several pathways involved in this process. Our data revealed differential constitutive expression of Notch genes and ligands in T lymphocytes and thymic dendritic cells (tDCs), suggesting their participation in human thymocyte maturation. nTreg analyses indicated that the Notch components function in parallel to promote maturation in the thymus. PMID:27504259

  5. Microwaves from GSM Mobile Telephones Affect 53BP1 and γ-H2AX Foci in Human Lymphocytes from Hypersensitive and Healthy Persons

    OpenAIRE

    Markovà, Eva; Hillert, Lena; Malmgren, Lars; Persson, Bertil R R; Belyaev, Igor Y.

    2005-01-01

    The data on biologic effects of nonthermal microwaves (MWs) from mobile telephones are diverse, and these effects are presently ignored by safety standards of the International Commission for Non-Ionizing Radiation Protection (ICNIRP). In the present study, we investigated effects of MWs of Global System for Mobile Communication (GSM) at different carrier frequencies on human lymphocytes from healthy persons and from persons reporting hypersensitivity to electromagnetic fields (EMFs). We meas...

  6. Adaptive Ensemble with Human Memorizing Characteristics for Data Stream Mining

    Directory of Open Access Journals (Sweden)

    Yanhuang Jiang

    2015-01-01

    Full Text Available Combining several classifiers on sequential chunks of training instances is a popular strategy for data stream mining with concept drifts. This paper introduces human recalling and forgetting mechanisms into a data stream mining system and proposes a Memorizing Based Data Stream Mining (MDSM model. In this model, each component classifier is regarded as a piece of knowledge that a human obtains through learning some materials and has a memory retention value reflecting its usefulness in the history. The classifiers with high memory retention values are reserved in a “knowledge repository.” When a new data chunk comes, most useful classifiers will be selected (recalled from the repository and compose the current target ensemble. Based on MDSM, we put forward a new algorithm, MAE (Memorizing Based Adaptive Ensemble, which uses Ebbinghaus forgetting curve as the forgetting mechanism and adopts ensemble pruning as the recalling mechanism. Compared with four popular data stream mining approaches on the datasets with different concept drifts, the experimental results show that MAE achieves high and stable predicting accuracy, especially for the applications with recurring or complex concept drifts. The results also prove the effectiveness of MDSM model.

  7. Zoledronic acid enhances Vδ2 T-lymphocyte antitumor response to human glioma cell lines.

    Science.gov (United States)

    Cimini, E; Piacentini, P; Sacchi, A; Gioia, C; Leone, S; Lauro, G M; Martini, F; Agrati, C

    2011-01-01

    Glioblastoma multiforme (GBM), the most frequent and aggressive primary brain tumor in humans, responds modestly to treatment: most patients survive less than one year after diagnosis, despite both classical and innovative treatment approaches. A recent paper focused on γδ T-cell response in GBM patients, suggesting the application of an immunomodulating strategy based on γδ T-cells which is already in clinical trials for other tumors. Human Vγ2 T-cells recognize changes in the mevalonate metabolic pathway of transformed cells by activating cytotoxic response, and by cytokine and chemokine release. Interestingly, this activation may also be induced in vivo by drugs, such as zoledronic acid, that induce the accumulation of Vγ2 T-cell ligand Isopentenyl-pyrophosphate by blocking the farnesyl pyrophosphate synthase enzyme. The aim of our work is to confirm whether bisphosphonate treatment would make glioma cell lines more susceptible to lysis by in vitro expanded γδ T-cells, improving their antitumor activity. We expanded in vitro human Vγ2 T-cells by phosphoantigen stimulation and tested their activity against glioma cell lines. Co-culture with glioma cells induced Vγ2 T-cell differentiation in effector/memory cells, killing glioma cells by the release of perforin. Interestingly, glioma cells were directly affected by zoledronic acid; moreover, treatment increased their activating ability on Vγ2 T-cells, inducing an effective antitumor cytotoxic response. Taken together, our results show that aminobisphosphonate drugs may play a dual role against GBM, by directly affecting tumor cells, and by enhancing the antitumor response of Vγ2 T-cells. Our results confirm the practicability of this approach as a new immunotherapeutic strategy for GBM treatment.

  8. Regulation of IL-13 synthesis in human lymphocytes: implications for asthma therapy

    OpenAIRE

    Pahl, Andreas; Zhang, Meixia; Kuss, Hildegard; Szelenyi, Istvan; Brune, Kay

    2002-01-01

    IL-13 is an important mediator in inflammatory diseases such as asthma. IL-13 is mainly produced by T cells. However, signalling pathways leading to induction of this cytokine are not well-characterized. We analysed the regulation of IL-13 in human peripheral blood mononuclear cells and CD4+ T cells.Cyclosporine (CsA) and FK-506 inhibited IL-13 synthesis, when cells were stimulated by TPA/ionomycin. However, stimulation by α-CD3/α-CD28 led to an enhanced IL-13 synthesis.NF-κB inhibitor N-tosy...

  9. Study of synergistic DNA-damaging effects of low-intensity 2450 MHz microwave and 4-nitroquinoline on human lymphocytes in vitro

    International Nuclear Information System (INIS)

    Objective: To study the synergistic DNA-damaging effects of low-intensity 2450 MHz micro-wave (MW, 5.0 mW/cm2) and 4-nitroquinoline (4-NQO) on human lymphocytes. Methods: The DNA damages of human lymphocytes treated with microwave and 4-NQO were detected using the comet assay. Three combination-exposure ways of MW and 4-NQO were used: MW irradiation before 4-NQO exposure (MW+4-NQO), simultaneous exposure to MW and 4-NQO(MW-4-NQO), and MW irradiation after 4-NQO exposure (4-NQO+MW). Results: The differences of DNA-damage indexes (comet tail length, comet shape and total comet length) between MW group and control group were not significant (P>0.05).When the dose of 4-NQO was 50 μmol/L or 25 μmol/L, the differences of DNA-damage indexes between MW+4-NQO group and corresponding 4-NQO group were significant (P0.05). Conclusion: Low-intensity 2450 MHz microwave does not induce DNA-damage directly, but could enhance the DNA-damaging effects induced by 4-NQO when human lymphocytes have been treated with MW irradiation before 4-NQO exposure

  10. Human Recombinant B7-H3 Expressed in E.coli Enhances T Lymphocyte Proliferation and IL-10 Secretion in Vitro

    Institute of Scientific and Technical Information of China (English)

    Guang-Bo ZHANG; Yong-Jing CHEN; Qin SHI; Hong-Bing MA; Yan GE; Qin WANG; Zhi JIANG; Ying XU; Xue-Guang ZHANG

    2004-01-01

    To explore the biofunctions of human B7-H3 on activated T lymphocyte,the gene of human B7-H3 encoding the extracellular region (IgV-like and IgC-like domains) was obtained by RT-PCR from human lung cells and subcloned into the prokaryotic expression vector pGEX-5X-3 to express glutathione S-transferase (GST) fusion protein.A 49 kD fusion protein (named as GST/hB7-H3 hereafter) was induced by IPTG and purified by standard methods reported in prokaryotic system.In the presence of the first signal imitated by anti-CD3 monoclonal antibody,T lymphocyte proliferation was observed by incubating purified T cells with soluble GST/hB7-H3 fusion protein by MTT assay.The concentrations of IFN-γ and IL-10 in the supernatants of T cells were determined by ELISA.The results showed that the GST/hB7-H3 protein produced in bacteria had modest biological activities to proliferate the T lymphocyte and enhance IFN-γ as well as IL-10 secretion.

  11. In vitro demonstration of a fundamental difference in the proliferation of murine and human bone marrow and lymphocytes following ultraviolet irradiation: relevance to bone marrow transplantation

    International Nuclear Information System (INIS)

    Exposure of rodent allogeneic donor marrow and splenocyte grafts to ultraviolet radiation (UVR) has been shown to permit durable engraftment at doses that abolish graft-versus-host disease (GVHD) and graft rejection. We have compared both murine and human alloreactive and mitogen induced lymphoid responses and bone marrow proliferation in mixed lymphocyte culture (MLC), phytomagglutinin (PHA)-induced proliferation and colony-forming unit granulocyte/macrophage (CFU-GM) assays using germicidal UVC (200-290 nm), broadband and narrowband UVB (290-320 nm) and UVA (320-400 nm) sources. Our data show a wavelength and dose-dependent reduction in lymphoid proliferation in the mouse with CFU-GM survival of 50-75% of control at doses required to abolish allogeneic lymphocyte responses for all lamps. In contrast, human lymphocyte responses are more resistant to UVC with CFU-GM proliferation reduced to zero when allostimulation is abolished. Mitogen-induced lymphoid responses show a similar wavelength-dependent sensitivity. Abolition of response in MLC using UV-irradiated stimulator cells was less sensitive than proliferation with UV-irradiated responder cells at all wavelengths in both species. With all sources, murine CFU-GM proliferation is less susceptible to UVR than human marrow at doses required to abolish lymphoid responses. (Author)

  12. Effect of low dose radiation in lymphocytes from children exposed to ionizing radiation after the Chernobyl accident. Cytogenetic, chromosome painting, GPA and adaptive response studies

    International Nuclear Information System (INIS)

    The present study concerns the monitoring of some children coming from Byelorussian, Ukrainian and Russian republics, exposed to the fall-out, or to the initial acute dose of radiation with the aim of assessing the effects of ionizing radiation on human health and of verifying the persisting of chromosomal damage several years after the accident. Both structural chromosomes damage (conventional cytogenetic and chromosome painting) and molecular mutation (GPA) have been investigated, moreover the possible induction of an adaptive response has been tested. (author)

  13. Evaluating the combinative effects on human lymphocyte DNA damage induced by Ultraviolet ray C plus 1.8 GHz microwaves using comet assay in vitro

    International Nuclear Information System (INIS)

    The objective of this study was to observe whether 1.8 GHz microwaves (MW) (SAR, 3 W/kg) exposure can influence human lymphocyte DNA damage induced by ultraviolet ray C (UVC). The lymphocytes, which were from three young healthy donors, were exposed to 254nm UVC at the doses of 0.25, 0.5, 0.75, 1.0, 1.5and 2.0 J m-2, respectively. The lymphocytes were irradiated by 1.8GHz MW (SAR, 3 W/kg) for 0, 1.5 and 4 h. The combinative exposure of UVC plus MW was conducted. The treated cells were incubated for 0, 1.5 and 4 h. Finally, comet assay was used to measure DNA damage of above treated lymphocytes. The results indicated that the difference of DNA damage induced between MW group and control group was not significant (P > 0.05). The MTLs induced by UVC were 1.71 ± 0.09, 2.02 ± 0.08, 2.27 ± 0.17, 2.27 ± 0.06, 2.25 ± 0.12, 2.24 ± 0.11 μm, respectively, which were significantly higher than that (0.96 ± 0.05 μm) of control (P < 0.01). MTLs of some sub-groups in combinative exposure groups at 1.5-h incubation were significantly lower that those of corresponding UVC sub-groups (P < 0.01 or P < 0.05). However, MTLs of some sub-groups in combinative exposure groups at 4-h incubation were significantly higher that those of corresponding UVC sub-groups (P < 0.01 or P < 0.05). In this experiment it was found that 1.8 GHz (SAR, 3 W/kg) MW exposure for 1.5 and 4 h did not enhance significantly human lymphocyte DNA damage, but could reduce and increase DNA damage of human lymphocytes induced by UVC at 1.5-h and 4-h incubation, respectively

  14. Interleukin-2 induces tyrosine phosphorylation and nuclear translocation of stat3 in human T lymphocytes

    DEFF Research Database (Denmark)

    Nielsen, M; Svejgaard, A; Skov, S;

    1994-01-01

    stimulation through the IL-2R induced tyrosine phosphorylation and subsequent nuclear translocation of stat3, a newly identified member of the signal transducers and activators of transcription (STAT) family of proteins. In contrast, stat1 proteins were not tyrosine phosphorylated after IL-2 ligation, whereas...... an apparent molecular mass of 84 kDa and was not recognized by stat3 or stat1 mAb or antisera. Since IL-2 induced nuclear translocation of the 84 kDa protein and stat3 followed identical kinetics, p84 is a candidate for a new, yet undefined, member of the STAT family. Taken together, we report that...... IL-2 induces tyrosine phosphorylation and subsequent nuclear translocation of stat3 and an as yet undefined 84-kDa protein in antigen-specific human T cell lines....

  15. Chromosome aberrations induced in human lymphocytes by U-235 fission neutrons. Pt. 1

    International Nuclear Information System (INIS)

    A set-up for irradiation of biological samples in the TRIGA Mark II research reactor in Ljubljana is described. Threshold activation detectors were used for characterisation of the neutron flux, and the accompanying gamma dose was measured by TLDs. Human peripheral blood samples were irradiated 'in vitro' and biological effects evaluated according to the unstable chromosomal aberrations induced. Biological effects of two types of cultivation of irradiated blood samples, the first immediately after irradiation and the second after 96 h storage, were studied. A significant difference in the incidence of chromosomal aberrations between these two types of samples was obtained, while our dose-response curve fitting coefficients are in both cases lower than could be found in the literature. (orig./MG)

  16. Protective effect of curcumin and its analog on γ-radiation induced DNA damage and lipid peroxidation in cultured human lymphocytes and isolated rat hepatocytes in vitro

    International Nuclear Information System (INIS)

    Ionizing radiation is known to induce oxidative stress through generation of reactive oxygen species (ROS) resulting in an imbalance of the pro-oxidant and antioxidant status in the cells, which is suggested to culminate in cell death. The present work was aimed to evaluate the radioprotective effect of curcumin and its analog on γ-radiation induced toxicity in cultured human lymphocytes and rat hepatocytes. Hepatocytes were isolated from the liver of rats by collagenase perfusion. The cellular changes were estimated using lipid peroxidative indices like thiobarbituric acid reactive substances (TBARS), the antioxidants superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and reduced glutathione (GSH). The DNA damage was analyzed by comet assay, cytokinesis blocked micro nucleus assay, dicentric aberrations and translocation frequency. Cell cycle distribution and measurement of the percentage of apoptotic cells were performed by flow cytometry analysis. To investigate whether the dietary agents like curcumin and its analog have a role on cell cycle regulation, we analyzed the changes in cell cycle profiles by using fluorescence activated cell sorter. The increase in the severity of DNA damage was observed with the increase dose (1, 2 and 4 Gy) of γ-radiation in cultured lymphocytes and hepatocytes. TBARS were increased significantly, whereas the levels of GSH and antioxidant enzymes were significantly decreased in γ-irradiated hepatocytes and lymphocytes. On pretreatment with curcumin and its analog (1, 5 and 10 μg/ml) showed a significant decrease in the levels of TBARS and DNA damage. The antioxidant enzymes were increased significantly along with the levels of GSH. The maximum protection of hepatocytes and lymphocytes was observed at 10 μg/ml curcumin and 5 μg/ml curcumin analog pretreatment. Thus, pretreatment with curcumin and its analog helps in protecting the normal hepatocytes and lymphocytes against γ-radiation induced cellular

  17. Dose Assessment using Chromosome Aberration Analyses in Human Peripheral Blood Lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Tae Ho; Kim, Jin-Hong; Kim, Jin Kyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    The healthy five donors were recruited to establish the dose-response calibration curve for chromosomal aberrations by ionizing radiation exposure. Our cytogenetic results revealed that the mean frequency of chromosome aberration increased with increasing radiation dose. In this study, dicentric assay and CBMN assay were compared considering the sensitivity and accuracy of dose estimation. Therefore, these chromosome aberration analyses will be the foundation for biological dosimetric analysis with additional research methods such as translocation and PCC assay. The conventional analysis of dicentric chromosomes in HPBL was suggested by Bender and Gooch in 1962. This assay has been for many years, the golden standard and the most specific method for ionizing radiation damage. The dicentric assay technique in HPBL has been shown as the most sensitive biological method and reliable bio-indicator of quantifying the radiation dose. In contrast, the micronucleus assay has advantages over the dicentric assay since it is rapid and requires less specialized expertise, and accordingly it can be applied to monitor a big population. The cytokinesis-block micronucleus (CBMN) assay is a suitable method for micronuceli measurement in cultured human as well as mammalian cells. The aim of our study was to establish the dose response curve of radiation-induced chromosome aberrations in HPBL by analyzing the frequency of dicentrics and micronuclei.

  18. Impact of climate change on human infectious diseases: Empirical evidence and human adaptation.

    Science.gov (United States)

    Wu, Xiaoxu; Lu, Yongmei; Zhou, Sen; Chen, Lifan; Xu, Bing

    2016-01-01

    Climate change refers to long-term shifts in weather conditions and patterns of extreme weather events. It may lead to changes in health threat to human beings, multiplying existing health problems. This review examines the scientific evidences on the impact of climate change on human infectious diseases. It identifies research progress and gaps on how human society may respond to, adapt to, and prepare for the related changes. Based on a survey of related publications between 1990 and 2015, the terms used for literature selection reflect three aspects--the components of infectious diseases, climate variables, and selected infectious diseases. Humans' vulnerability to the potential health impacts by climate change is evident in literature. As an active agent, human beings may control the related health effects that may be effectively controlled through adopting proactive measures, including better understanding of the climate change patterns and of the compound disease-specific health effects, and effective allocation of technologies and resources to promote healthy lifestyles and public awareness. The following adaptation measures are recommended: 1) to go beyond empirical observations of the association between climate change and infectious diseases and develop more scientific explanations, 2) to improve the prediction of spatial-temporal process of climate change and the associated shifts in infectious diseases at various spatial and temporal scales, and 3) to establish locally effective early warning systems for the health effects of predicated climate change.

  19. Impact of climate change on human infectious diseases: Empirical evidence and human adaptation.

    Science.gov (United States)

    Wu, Xiaoxu; Lu, Yongmei; Zhou, Sen; Chen, Lifan; Xu, Bing

    2016-01-01

    Climate change refers to long-term shifts in weather conditions and patterns of extreme weather events. It may lead to changes in health threat to human beings, multiplying existing health problems. This review examines the scientific evidences on the impact of climate change on human infectious diseases. It identifies research progress and gaps on how human society may respond to, adapt to, and prepare for the related changes. Based on a survey of related publications between 1990 and 2015, the terms used for literature selection reflect three aspects--the components of infectious diseases, climate variables, and selected infectious diseases. Humans' vulnerability to the potential health impacts by climate change is evident in literature. As an active agent, human beings may control the related health effects that may be effectively controlled through adopting proactive measures, including better understanding of the climate change patterns and of the compound disease-specific health effects, and effective allocation of technologies and resources to promote healthy lifestyles and public awareness. The following adaptation measures are recommended: 1) to go beyond empirical observations of the association between climate change and infectious diseases and develop more scientific explanations, 2) to improve the prediction of spatial-temporal process of climate change and the associated shifts in infectious diseases at various spatial and temporal scales, and 3) to establish locally effective early warning systems for the health effects of predicated climate change. PMID:26479830

  20. Selective destruction of mouse islet beta cells by human T lymphocytes in a newly-established humanized type 1 diabetic model

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Yong, E-mail: yongzhao@uic.edu [Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612 (United States); Guo, Chengshan; Hwang, David; Lin, Brian; Dingeldein, Michael; Mihailescu, Dan; Sam, Susan; Sidhwani, Seema [Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612 (United States); Zhang, Yongkang [Department of Pharmacology, University of Illinois at Chicago, Chicago, IL 60612 (United States); Jain, Sumit [Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612 (United States); Skidgel, Randal A. [Department of Pharmacology, University of Illinois at Chicago, Chicago, IL 60612 (United States); Prabhakar, Bellur S. [Department of Immunology and Microbiology, University of Illinois at Chicago, Chicago, IL 60612 (United States); Mazzone, Theodore [Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612 (United States); Holterman, Mark J. [Department of Surgery, University of Illinois at Chicago, Chicago, IL 60612 (United States)

    2010-09-03

    Research highlights: {yields} Establish a human immune-mediated type 1 diabetic model in NOD-scid IL2r{gamma}{sup null} mice. {yields} Using the irradiated diabetic NOD mouse spleen mononuclear cells as trigger. {yields} The islet {beta} cells were selectively destroyed by infiltrated human T cells. {yields} The model can facilitate translational research to find a cure for type 1 diabetes. -- Abstract: Type 1 diabetes (T1D) is caused by a T cell-mediated autoimmune response that leads to the loss of insulin-producing {beta} cells. The optimal preclinical testing of promising therapies would be aided by a humanized immune-mediated T1D model. We develop this model in NOD-scid IL2r{gamma}{sup null} mice. The selective destruction of pancreatic islet {beta} cells was mediated by human T lymphocytes after an initial trigger was supplied by the injection of irradiated spleen mononuclear cells (SMC) from diabetic nonobese diabetic (NOD) mice. This resulted in severe insulitis, a marked loss of total {beta}-cell mass, and other related phenotypes of T1D. The migration of human T cells to pancreatic islets was controlled by the {beta} cell-produced highly conserved chemokine stromal cell-derived factor 1 (SDF-1) and its receptor C-X-C chemokine receptor (CXCR) 4, as demonstrated by in vivo blocking experiments using antibody to CXCR4. The specificity of humanized T cell-mediated immune responses against islet {beta} cells was generated by the local inflammatory microenvironment in pancreatic islets including human CD4{sup +} T cell infiltration and clonal expansion, and the mouse islet {beta}-cell-derived CD1d-mediated human iNKT activation. The selective destruction of mouse islet {beta} cells by a human T cell-mediated immune response in this humanized T1D model can mimic those observed in T1D patients. This model can provide a valuable tool for translational research into T1D.