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I M Dozmorov

Publications and source records attributed to I M Dozmorov.

33 records · Page 2Linked to original sources
PubMed1985

[Regulating role of the B-lymphocytes in lymphocyte interaction with allogeneic hematopoietic stem cells].

The preparative separation of lymph-node cells according to their charge and the study of the activity of each fraction have revealed that B-lymphocytes in the lymph nodes of mice have a regulating function in the phenomenon of the inactivation of allogeneic hematopoietic stem cells. The analysis of the dependence of effects, obtained in various experiments, on the ratio of B-lymphocytes and hematopoietic stem cells indicates that stem cells serve as targets for B-lymphocytes and the most probable mechanism of the above-mentioned effects is the direct interaction of the cells, one regulatory B-lymphocyte being capable of interacting with one target cell. Depending on the ratio of B-lymphocytes and stem cells, the inactivating effect may be either suppressed (the suppressor activity of B-lymphocytes) or enhanced (the helper activity of B-lymphocytes). The quantitative characteristics of the regulating activity of B-lymphocytes have been introduced.

Animals↗
PubMed1985

[Characteristics of the B lymphocytes participating in the reaction of allogeneic stem cell inactivation].

In this work the B-cells of mouse lymph nodes are characterized. B-cells produce a helper effect on the capacity of the T-lymphocytes of the lymph nodes for inactivating nonsyngeneic stem cells. The study has revealed that the genetic heterogeneity of the B-lymphocytes does not lead to the abolition of their helper activity. B-lymphocytes of "B-mice" have also been shown to be capable of enhancing the inactivating activity of T-cells.

Animals↗
PubMed1983

[Effect of size-fractionated thymocytes on the number of hematopoietic stem cells in the bone marrow of sublethally irradiated mice].

A study was of the influence of size-fractionated thymocytes in the density gradient of bovine serum albumin on the number of CFUs in the bone marrow of mice exposed to sublethal irradiation. Subject to separation were thymocytes obtained from intact mice and mice after multiple injections of dexamethasone (DM). Two cell populations were demonstrated during separation of thymocytes from intact mice. Injection of the first cell population brought about a decrease in the number of CFUs in the bone marrow during postradiation recovery, whereas injection of other thymocyte subpopulation resulted in an increase in CFUs. The use of thymocytes obtained from DM treated mice enabled the detection of an increase in bone marrow CFUs, induced by both unfractionated thymocytes and two fractions of thymocytes.

Animals↗
PubMedDate not supplied

[The role of the serum interleukin-2 inhibitor in the rejection of allogeneic hematopoietic tissue in sublethally irradiated mice].

The influence of ionizing radiation (5 Gy) on the interleukin-2 inhibitor in mouse serum has been investigated. It has been shown that the concentration of IL-2 inhibitor decreases on days 3-6 and increases considerably on days 10-15 after irradiation. A correlation has been found between the number of T-helpers in spleens of exposed allogenic chimeras and low IL-2 inhibitor content of serum. An attempt has been made to use the increased IL-2 inhibitor level for improving the acceptance of allogenic cells in the sublethally exposed mice.

Animals↗
PubMedDate not supplied

[The participation of oxygen in the process of the interphase death of T-lymphocytes following irradiation in vivo].

The ability of lymphocytes to inhibit proliferation of non-syngeneic stem cells decreases differently after exposure in vivo and in vitro. The causes of the observed differences and the mechanism of radiation impairment of this function under different irradiation conditions have been investigated. Cells exposed in vivo die in the interphase irreversibly. The newly formed lymphocytes start the repair process as late as one month after irradiation. The injury to in vivo exposed cells is severer due to the presence of oxygen in tissues. A definite time interval is needed for the damaging effect of oxygen radicals to be implemented: the effect is maximum as early as 4 h following irradiation. With in vivo exposure under hypoxic conditions the functional activity of lymphocytes is the same as that of lymphocytes irradiated in vitro with the same dose. In vitro irradiation of lymphocytes at a high oxygen content causes a decrease in the functional activity of cells.

Animals↗
PubMedDate not supplied

[Effect of administration of allogeneic lymphocytes on the survival of sublethally irradiated mice].

The administration of allogenic (CBA----C57B1/6) and semi-allogenic (CBA----F1) lymphocytes to sublethally exposed recipient mice either stimulates or inactivates endogenous colony-formation depending on the dose of lymphocytes administered. The stimulation of endogenous colony-formation correlates with the increased survival rate after radiation doses that decrease the survival rate of the control recipients.

Animals↗
PubMedDate not supplied

[Effect of irradiation on the regulatory function of B-lymphocytes].

A study was made of the effect of irradiation of B-lymphocytes with doses of 0-464.4 mC/kg on their regulatory function in activating the allogenic haemopoietic stem cells of mice. Irradiation changed the function of B-lymphocytes leading to transformation of their helper effect into the suppressible one. The parameters of the radiation damage to B-lymphocytes-regulators were determined.

Animals↗
PubMedDate not supplied

[Action of radiation on cell interactions in the phenomenon of nonsyngeneic stem cell inactivation. Quantitative parameters of the regulating effect of B-lymphocytes].

Quantitative regularities have been revealed in the regulatory action of B-lymphocytes from mouse lymph nodes on killer activity of T-lymphocytes of low electrophoretic motility. It was shown that the radiation-induced changes in the mode of action of B-lymphocytes may be attributed to a decrease in the number of active cells.

Animals↗
PubMedDate not supplied

[Adaptive T-lymphocyte differentiation in an allogeneic environment].

Some patterns of adaptive changes of the hemopoietic stem cells in allogenic environment and the functional activity and specificity of cytotoxic T-lymphocytes developing from them and responsible for the inactivation of allogenic hemopoietic stem cells were studied on the radiation chimaeras. The allogenic environment did not prevent the functional maturation of these T-lymphocytes. The phenotype of T-lymphocytes matured under the conditions of allogenic recipient is similar but not identical with that of lymphocytes of the recipient mouse strain.

Adaptation, Physiological↗
PubMedDate not supplied

[Effect of radiation on cell interactions in the phenomenon of non-syngeneic stem cell inactivation. Changes in B-lymphocyte function after irradiation].

A study was made of the changes in the mode of interaction between T- and B-lymphocytes of mouse lymph nodes with respect to the phenomenon of inactivation of non-syngeneic haemopoietic stem cells. It was shown that irradiation of B-lymphocytes with doses of 77.4--232.2 mC/kg changes their helper activity into a suppressor activity with regard to T-cell-killers having a low electrophoretic mobility.

Animals↗