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Biomedical subjects

E N Antropova

Publications and source records attributed to E N Antropova.

At least 19 recordsLinked to original sources
PubMed2004

[Outcome of the long-term isolation on the development of allergic reactions in humans].

Studied were consequences of long-term isolation in airtight environment for development of the type-I (IgE-antibodies production) and type-IV (involvement of sensibilized T-lymphocytes) allergic reactions in humans. No significant changes in total IgE, specific IgE-antibodies for domestic, epidermal, fungal, grass pollen and food-borne allergens or serum IL-4 level were found in the period of the 240-d isolation with the microclimate and atmospheric parameters within their normal variations, and on completion of the experiment. Yet, after 3 mos. in isolation all subjects exhibited inhibited leukocyte migration in the presence of tuberculin. These findings bear witness to an activation of sensibilized lymphocytes known as effectors of delayed hypersensitivity.

Adult↗
PubMed2004

Cell interactions in microgravity: cytotoxic effects of natural killer cells in vitro.

To study cell-to-cell interactions in microgravity we examined the functional activity of natural killer cells on board of the ISS. NK cells are the effector cells with direct cytotoxic activity to oncogenic, virus-infected cells and cells with modified differentiation. Ground-based experiments have shown that the examination of target cell lysis after incubation with NK cells is a simple and informative model for studying the influence of microgravity. NK cytotoxicity was measured as the value of non-degradeted labeled myeloblasts (K-562) after 24 hrs exposure with human lymphocytes in suspension. A special device was developed for space flight experiments. Human cultured lymphocytes and labeled K-562 cells were loaded into special syringes and delivered to the Russian segment of the ISS. Cosmonauts prepared co-cultured suspensions during the first day of microgravity, exposed them at 37 degrees C for 24 hrs and then separated H3-labeled cells on special filters. The results of ISS-8 mission showed that human NK cells in vitro remain lysis activity toward target cells in microgravity. The basal level of NK cytotoxicity was low and we did not found significant differences between "control" and "flight" values. Interferon production during the interaction between immune and target cells (ratio 10:1) in microgravity did not differ compared with ground-based control experiments. Ground exposure of the same lymphocyte samples with K-562 cells to 24 hrs clinorotation also did not lead to significant differences. These experiments paved the way for understanding the cell interaction mechanisms in space flight and the obtained results suggest that microgravity does not disrupt the interaction of NK cells with tumor cells.

Cell Communication↗
PubMed2001

Expression of cell adhesion molecules and lymphocyte-endothelium interaction under simulated hypogravity in vitro.

Using histochemical staining and FACS-analysis we have studied the basal and TNF-alpha induced expression of E-selectin, ICAM-1 and VCAM-1 in human umbilical vein endothelial cells (ECs) exposed to simulated hypogravity. Control ECs did not contain detectable amounts of E-selectin or VCAM-1 but were ICAM-1 positive. As soon as after 6-8 hrs of clinorotation at 5 RPM the cellular content of ICAM- 1 increased. Moreover, hypogravity potentiated the effect of inflammatory cytokines (TNF-alpha and IL-1) on ICAM-1 expression. No increase in E-selectin or VCAM-1 expression was observed in ECs exposed to hypogravity itself. However, hypogravity reduced E-selectin and VCAM-1 expression in cell cultures activated by cytokines, more visible at their low (5-10 U/ml) concentrations. Both, control and clinorotated ECs poorly supported spontaneous lymphocyte adhesion; the adhesion of PMA-activated leukocytes was 15-20-fold higher. The interaction of unstimulated lymphocytes with cytokine-activated endothelium was more noticeable but significantly lower in cultures exposed to hypogravity. Activated blood cells interacted with endothelium more effectively, particularly, under hypogravity. Obtained results suggest that EC adhesion molecule expression and endothelium-lymphocyte interaction are altered under simulated hypogravity conditions in direction of increase of endotlielial adhesiveness for activated blood cells.

Cells, Cultured↗
PubMed2000

[Immunologic reactivity and status of the intestinal viral flora of humans in pressurized chambers].

Immunity status and intestinal viral flora were studied in 5 experiments with long-term exposure of 26 male subjects in pressurized chamber. In two experiments with congenital microclimate and gaseous environment cellular and humoral indices of immunity did not deviate from the physiological norm. None of 14 subjects in these experiments was identified as a virus-carrier. In three experiments with hard environmental conditions (elevated concentrations of ammonia and carbon dioxide) viruses were isolated from 8 out of 12 subjects. Activation of viral flora mainly occurred on a background of impaired immunologic reactivity. In two experiments carriage of virus was asymptomatic; in the third experiment with the rise of ammonia up to 7 mg/m3 two subjects developed clinic signs that could have been engendered by enteric viruses, the Coxsackie B strain specifically.

Adult↗
PubMed1999

[The diagnosis of disorders of the T-cell immunity component in space flight].

The investigation yielded two modifications of the procedure FOR determination of T-lymphocytes' functional activity in microsamples of the finger capillary blood and PHA-assisted cultivation of cells in syringe for subsequent morphological analysis by cosmonauts in flight. Testing of the proposed modifications in 14 healthy donors with unconstrained work/rest schedule, 4 volunteers in 60- and 6 volunteers in 120-day HDT showed a rather high comparability of data obtained with the modified and genuine procedures for determination of the T-lymphocytes proliferative activity in cosmonauts before and after orbital flights. Thus, the modified procedures can be successfully used for monitoring the immune status of cosmonauts on missions, and individuals exposed to extreme environments.

Cell Culture Techniques↗
PubMed1998

[Human cellular immunity and space flights].

Results of studying cellular immunity of crew members of long-term space missions, data of an experiment with extended head-down tilting of human subjects (HDT), and data obtained in the course of adapting immunologic test methods for the use in microgravity are summarized. Disorders in immunologic reactivity were shown to occur under the conditions of space flight. They included decreases in both quantitative and functional indices of cellular immunity, and emergence of signs of sensibilization to different allergens. The modified tests were evaluated by efficacy of determination of the proliferative activity of lymphocytes in minimal volumes of capillary blood inside one-piece syringes with a medium containing PHA and the Cytodex-1 suspension, evaluation of natural cytotoxicity on the level of an effector cell (number of peripheral blood lymphocytes capable of producing conjugates with fixed target cells). Sensibilization to allergens of normal human microflora was tested in analogs of routine hematocrit capillaries used for examination of healthy donors under ordinary rest-work regimen. No significant differences between the standard and modified tests were revealed. The proposed test modifications are quite simple in use and require minimum of equipment.

Adult↗
PubMed1997

[Immune resistance of humans during extended isolation].

Analyzed were parameters of the immune reactivity and allergological status of participants in the 135-day chamber experiment with periods of induced psychoemotional strain. Stressful situations gave rise to shifts in the antibody system, i.e. decreased blood levels of ImgA, ImgM, and ImgG, decline in the functional activity of T-lymphocytes, suppression of the cytokinetic activity of lymphocytes-natural killers, and sensibilization to various allergens. Totality of these shifts resembles the ones which are typically seen during initial readaptation to the Earth's conditions on after long-term space mission.

Humans↗
PubMedDate not supplied

[Modification of a method for determining the cytotoxic activity of lymphocytes--natural killers in space experiments].

A space modification of a method for determining the cytotoxic activity of natural killers (NK) uses cultures of human lymphocytes and re-inoculated suspension of tumorous myeloblasts K-562. The 3H-uridine labeled target-cells fixated in 0.1 % formalin solution proved to be best suited to the conditions prohibiting regular recharge of cultural medium and utilization of radioactive agents. The following practical conclusions were made from the space-flown experiment: pre-launch procedures (lymphocyte isolation and delivery to the launch site) and time period till dock must not be longer than 5 days (1) and during transportation to the orbiting vehicle cell cultures must be kept at 18-20 degrees C (2). The modified method can be employed to study various aspects of cell interaction such as the NK ability to destroy target-cells in suspension cultured exposed in microgravity.

Antimicrobial Cationic Peptides↗
PubMedDate not supplied

[Immunoglobulin e and allergen-specific IgE antibodies in cosmonauts before and after long-duration missions on the International Space Station].

Immunoglobulins (IgG, IgA, IgM, IgE), specific IgE-antibodies, and interleukin-4 (IL-4) were investigated in blood serum of nine cosmonauts before and after 128- to 195-day ISS missions. It was shown that long-duration space flight does not change significantly the content of serum immunoglobulins, allergen-specific IgE-antibodies or IL-4. Analysis for probable ratios of the total IgE and IL-4 contents in the pre- and post-flight periods did not reveal any linear correlation of these parameters.

Adaptation, Physiological↗