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I Konstantinova

Publications and source records attributed to I Konstantinova.

11 recordsLinked to original sources
PubMed1997

Changes in the immune system during and after spaceflight.

The results of immunological analyses before, during and after spaceflight, have established the fact that spaceflight can result in a blunting of the immune mechanisms of human crew members and animal test species. There is some evidence that the immune function changes in short-term flights resemble those occurring after acute stress, while the changes during long-term flights resemble those caused by chronic stress. In addition, this blunting of the immune function occurs concomitant with a relative increase in potentially infectious microorganisms in the space cabin environment. This combination of events results in an increased probability of inflight infectious events. The realization of this probability has been shown to be partially negated by the judicious use of a preflight health stabilization program and other operational countermeasures. The continuation of these countermeasures, as well as microbial and immunological monitoring, are recommended for continued spaceflight safety.

Acute Disease↗
PubMed1996

Effect of SLS-2 spaceflight on immunologic parameters of rats.

During the Spacelab Life Sciences-2 mission, rats were dissected in space and biosamples were returned to Earth for analysis. Immunologic studies addressed the kinetics of T lymphocyte proliferative responses, cytotoxic activity of natural killer cells, and cytokine production. Experiments were performed by using spleen and bone marrow of rats dissected before flight, during flight, immediately after landing of the space shuttle (R + 0), or 14 days after landing (R + 14), as well as those of respective control animals. Each group consisted of five male Sprague-Dawley rats. It was demonstrated that T lymphocyte activity of rats dissected in flight was significantly decreased compared with the controls. This was observed during 48-, 72-, and 96-h cultivation and stimulation with the following mitogenic stimuli: concanavalin A (Con A; 0.1, 1.0, and 10.0 mg/ml), phytohemagglutinin (PHA; 2.5 mg/ml), and interleukin-2 (IL-2; 1 U/ml). The cell proliferation rate in rats dissected immediately after landing did not decrease, whereas that in rats dissected at R + 14 increased. The activity of spleen natural killer cells was reduced in response to 51Cr-labeled target cells during flight (YAC-1 and K-562) and after flight (YAC-1). At R + 14, their activity returned to normal. Another technique employed to measure natural cytotoxicity, using [3H]uridine-labeled target cells and ribonuclease, did not reveal any differences between control and experimental groups. In bone marrow, the activity of natural killer cells did not vary significantly. The production of IL-1, IL-2, tumor necrosis factor (TNF)-alpha, and TNF-beta in spleen cell cultures of the flight rats was reduced. At R + 0, IL-1 and TNF-beta levels remained lowered, whereas TNF-alpha was increased. At R + 0, interferon-alpha and interferon-gamma levels were diminished. In summary, cell-mediated immunity in rats was significantly suppressed during flight. The time course variation of immune parameters after flight suggests that the changes may truly indicate a response of the immune system to spaceflight conditions that could increase over time.

Animals↗
PubMed1994

Cellular immunity in cosmonauts during long duration spaceflight on board the orbital MIR station.

To investigate the effect of spaceflight on cell mediated immunity we tested delayed-type hypersensitivity (DTH) in 5 cosmonauts on three missions in the orbital space station MIR. DTH was determined by the intradermal application of seven antigens and a control using the standardized Multitest Mérieux. This multiple prick puncture test was applied prior to, during, and following missions, which lasted for up to 177 d. In four of the five cosmonauts, reaction scores of DTH-responses below the warning level were noted during flight (two subjects) or following landing (two subjects). In-flight reductions of DTH-responses were possibly induced by a series of stressful extravehicular activities and recovered to normal levels after landing. The results confirm earlier observations of a decreased lymphocyte function following spaceflights determined by means of mitogenic responsiveness of lymphocytes. Thus, the notion of a possibly impaired cell-mediated immunity under stress in association with spaceflight gains further support.

Humans↗
PubMed1993

Immune changes in test animals during spaceflight.

Over the past two decades, it has become apparent that changes in immune parameters occur in cosmonauts and astronauts after spaceflight. Therefore, interest has been generated in the use of animal surrogates to better understand the nature and extent of these changes, the mechanism of these changes, and to allow the possible development of countermeasures. Among the changes noted in animals after spaceflight are alterations in lymphocytic blastogenesis, cytokine function, natural killer cell activity, and colony-stimulating factors. The nature and significance of spaceflight-induced changes in immune responses will be the focus of this review.

Animals↗
PubMed1991

Inhibition of phorbol ester-induced cell activation in microgravity.

T lymphocytes and monocytes were exposed to microgravity and activated to produce interleukin 2 and interleukin 1, respectively. When Jurkat T cells were triggered with monoclonal antibodies directed against the CD3/T cell receptor complex in the presence of THP-1 monocytes used as accessory cells, cell-to-cell contacts took place in microgravity leading to normal production of interleukin 2 and interleukin 1, as compared to ground controls. In contrast, when cells were individually stimulated by soluble substances including a protein kinase C activating phorbol ester, the production of interleukin 1 and interleukin 2 was dramatically inhibited during microgravity exposure. This result indicates that microgravity may affect the cellular target of phorbol ester.

Calcimycin↗
PubMed1991

Effects of long duration spaceflight on human T lymphocyte and monocyte activity.

Experiments were performed on blood samples from 5 cosmonauts in order to investigate the effects of long duration spaceflight (26 to 166 days) on immune activity. The experiments were performed on cultured mononuclear cells purified from blood samples collected during the preflight period and 24 h after landing. The production of interleukin 2, which is the major cytokine involved in T lymphocyte proliferation, was found to be enhanced after flight in some individuals, whereas the ability of mitogen-stimulated cells to express interleukin 2 receptor was impaired 24 h after flight for two cosmonauts out of five. Normal interleukin 2 receptor expression was obtained in all cases when lymphocytes were directly activated by a protein kinase C activating phorbol ester. On the other hand, no significant changes were observed in interleukin 1 production by cultured peripheral blood mononuclear cells. Lastly, the distribution of T lymphocytes subsets was examined in peripheral blood sampled 24 h after landing and was found to be within normal values.

Humans↗
PubMed1983

Results of space experiment program "Interferon". I. Production of interferon in vitro by human lymphocytes aboard space laboratory Solyut-6 ("Interferon I") and influence of space flight on lymphocyte functions of cosmonauts ("Interferon III").

The results of the biological space experiment "Interferon" performed by two international cosmonaut crews aboard the space laboratory Solyut-6 are reported. Human lymphocytes separated from the blood of healthy donors and placed into "Interferon I" equipment could be kept for 7 days in suspension culture under spaceflight conditions. Interferon production could be induced in human lymphocytes by preparations of different origin, such as virus, synthetic polyribonucleotides, bacterial protein and plant pigment. An increased lymphocyte interferon production was observed in the space laboratory as compared to the ground control. A decrease of induced interferon production and natural killer cell activity was observed in the cosmonauts' lymphocytes on the 1st day on Earth after 7 days spaceflight.

Cell Membrane Permeability↗
PubMed1983

Results of space experiment program "Interferon". II. Influence of spaceflight conditions on the activity of interferon preparations and interferon inducers ("Interferon II").

The influence of spaceflight conditions on the biological activity of HuIFN-alpha preparations (lyophilized, in solution and in ointment) and interferon inducers was studied. In antiviral activity no difference was observed between the samples kept aboard the spaceship and the controls kept under ground conditions. The interferon inducers poly I:C, poly G:C and gossipol placed in the space laboratory for 7 days maintained their interferon-inducing capacity. The circulating interferon level in mice was the same irrespective of the induction being performed with flight or ground-control samples of inducers.

Animals↗
PubMedDate not supplied

Results of space experiment program "Interferon".

The results of the biological space experiment "Interferon" performed by two international cosmonaut teams (26 May 1980, and 16 May 1981) aboard space laboratory Solyut-6 are reported: (1) Human lymphocytes separated from blood of healthy donors and placed into "Interferon I" equipment could be kept for 7 days in suspension culture under spaceflight conditions. Interferon production could be induced in human lymphocytes by preparations of different origin: virus, synthetic polyribonucleotides, bacterial protein and plant pigment. An increased lymphocyte interferon production in space laboratory compared to ground control was observed. (2) Human interferon preparations and interferon inducers placed in space laboratory at room temperature for 7 days maintained their biological activity. (3) A decrease of induced interferon production and natural killer activity of lymphocytes isolated from peripheral blood of cosmonauts was observed on the 1st day on Earth after 7-days spaceflight.

Animals↗