[The phenotypic characteristics of T-lymphocytes that interact with hematopoietic stem cells: the expression of the antigens Lyt-1, Lyt-2 and L3T4]. / Fenotipicheskaia kharakteristika T-limfotsitov, vzaimodeistvuiushchikh s krovetvornymi stvolovymi kletkami: ékspressiia antigenov Lyt-1, Lyt-2 i L3T4.

The role of T-lymphocytes, bearing antigens Lyt-1, Lyt-2 and L3T4, in regulation of the functional activity of blood-forming precursor cells of syngen and non-syngen origin was investigated. The treatment of cells of murine lymphatic nidi with monoclonal antibodies to the above antigens and with the complement did not abolish the capacity of T-lymphocytes of controlling proliferation and differentiation of syngen and allogen blood-forming precursor cells. The subpopulation characteristics of lymphocytes interacting with the stem cells is discussed.

[The effect of kemantane on T-helpers and T-suppressors]. / Vliianie kemantana na T-khelpery i T-supressory.

The study of Kemantan on functionally alternative humoral immunity regulator cells: T-helpers and antigen-specific T-suppressors, including their induction, accumulation and functioning, was studied. Kemantan in doses of 0.2-200 mg/kg, introduced to the donors of T-helpers 2 days before they were taken, stimulated their activity 1.5- to 2-fold (with p less than 0.05). Kemantan had no influence on the functional activity of T-suppressors, as well as on their induction and accumulation.

[The mitostatic and lymphotoxic action of kemantane and its effect on B-suppressors]. / Mitostaticheskoe i limfotoksicheskoe deistvie kemantana i ego vliianie na B-supressory.

The in vivo study of the influence of Kemantan on the growth of endogenous colonies in the spleen of sublethally (6 Gy) irradiated (CBA x C57BL/6J) F1 mice (mitostatic action) and on the capacity of transplanted lymphocytes of CBA mice for suppressing their multiplication (lymphotoxic action) was carried out. Besides the capacity of Kemantan for affecting the induction, formation and functioning of B-suppressors of antibody formation was studied. As revealed in this study, Kemantan in doses of 0.2-200 mg/kg did not produce a mitostatic and lymphotoxic effect and had no influence on the realization of the suppressing action of mature B-suppressors. In doses of 20 and 200 mr/kg Kemantan, injected to donors at the phase of the induction and accumulation of B-suppressors, abolished their formation.

[The need of B-helpers for the T-lymphocyte regulation of the process of hematopoietic stem cell differentiation]. / Neobkhodimost' B-khelperov dlia reguliatsii T-limfotsitami protsessa differentsirovki stvolovykh krovetvornykh kletok.

We have detected and characterized a subpopulation of immunoregulatory cells, i.e., B-helpers capable to enhance the activity of Td-lymphocytes and controlling differentiation of syngeneic hemopoietic stem cells in mouse spleen and bone marrow. B-helpers found in the spleen and lymphatic nodes are resistant to radiation (at a dose of 6 Gr) but are impaired when irradiated at 9 Gr. Manifestation of the helper activity does not require either DNA or RNA synthesis but depends on protein synthesis and is mediated by soluble transmitter substances. Initial activation of B-helpers by lipopolysaccharide or alloantigens does not affect their helper functions. In the absence of T-lymphocytes B-cells do not affect differentiation of hemopoietic stem cells; interaction of B-helpers with differentiating Td-lymphocytes is not genetically restricted. Using preparative electrophoresis, we could isolate fractions of Td-lymphocytes which require or do not require B-helper cells in order to induce change in differentiation of hemopoietic stem cells from mainly erythroid to preferentially granulocyte pathway.

[Myelopeptide correction of the differentiation of hematopoietic precursor cells in mice with experimental T-immunodeficiency]. / Korrektsiia mielopeptidami differentsirovki krovetvornykh kletok-predshestvennikov u myshei s éksperimental'nym T-immunodefitsitom.

The influence of myelopeptides on differentiation of bone marrow haemopoietic precursors cells in thymectomized and normal mice has been studied in vivo. The introduction of myelopeptides decreased the number of erythroid (E) colonies and increased that of granulocytic ones (G). This results in the decrease of initially raised E/G ratio in thymectomized mice (from 4.3) down to 1.3). Myelopeptides exerted no influence on haemopoietic precursors in normal mice (E/G-2.0).

[Differential radiation susceptibility of endogenous precursor cells forming "early" and "late" hematopoietic foci in the spleen of mice]. / Razlichnaia radioporazhaemost' éndogennykh kletok-predshestvennikov, formiruiushchikh v selezenke myshei "rannie " i "pozdnie" ochagi krovetvoreniia.

No colonies were found in the spleen at "early" times (7-8 days) after irradiation of mice with doses of 8-9 Gy, while at "later" times (after 15 days) a confluent growth of the colonies was observed. The endogenous splenic foci of haemopoiesis of the "late" type were characterized by the preferable growth of granulocytic colonies.

[Effect of T-cell mitogens and T-lymphocyte deficiency on splenic colony formation]. / Vliianie T-kletochnykh mitogenov i defitsita T-limfotsitov na selezenochnoe kolonieobrazovanie.

A study was made of the influence of T-cell mitogens (Con A and PHA) on the colony formation and differentiation of hemopoietic stem cells from normal and thymectomized mice, as well as of the relationship between the colony formation and the dose of injected thymocytes. The incubation of bone marrow cells with Con A and PHA was shown to inhibit the growth of spleen colonies. This inhibition is reduced by thymocytes within the dose intervals of 0.25-2.0 X 10(7) cells/mouse. Administration of these agents serially has led to the potentiation of inhibition effect and to the inability of thymocytes to reverse it. Con A and PHA exert no effect on the differentiation of stem cells. Incubation of the bone marrow cells from thymectomized mice with Con A is much less effective in the depression of colony formation, if compared with the treatment by intact bone marrow preparations. A reversed picture was observed using antiserum to mouse brain (RAMBS). It is proposed that regulation of stem cells is governed by different subpopulations of thymocytes.

[Characteristics of the T-lymphocytes interacting with hematopoietic stem cells: the expression of Lyt-3 antigen]. / Kharakteristika T-limfotsitov, vzaimodeistvuiushchikh s krovetvornymi stvolovymi kletkami: ékspressiia antigena Lyt-3.

The lymph node cells were treated with monoclonal anti-Lyt-3 antibodies (anti-Lyt-3) and complement. Their interaction with colony-forming units (CFU) of bone marrow was studied. Anti-Lyt-3 did not affect the activity of T-lymphocytes, which changed the pattern of syngenic CFU differentiation in spleen of irradiated mice. On the contrary, the activity of T-lymphocytes, which inactivated proliferation and differentiation of non-syngenic CFU in spleen, was decreased. In the peritoneal cavity of irradiated mice antibodies did not affect the activity of T-lymphocytes which suppressed the colony-formation of non-syngenic stem cells and switched off the activity of T-lymphocytes that stimulated syngenic CFU colony-formation. The subpopulation characteristics of regulatory and effector T-cells has been analysed.

[Effect of syngeneic lymphocytes, T immunodeficiency and the genotype of bone marrow donors on the differentiation of early and late splenic colonies]. / Vliianie singennykh limfotsitov, T-immunodefitsita i genotipa donorov kostnogo mozga na differentsirovku "rannikh" i "pozdnikh" selezenochnykh kolonii.

The formation of "early" (5-8 days) and "late" (12-14 days) colonies in spleen of lethally irradiated syngeneic or hybrid recipients after transplantation of bone marrow cells has been studied. The differentiation pattern did not depend on bone marrow cell donor's genotype and the donor-recipient combination. Erythroid to granulocyte colonies ratio (E/G) equals 2. Change of direction of bone marrow colony-forming units (CFU) differentiation has the same pattern at different stages of colony-formation. Under the influence of antigen-stimulated lymphocytes the granulopoiesis (E/G 0.3-0.5) dominanted. The thymectomy of adult animals leads to a predominant formation of erythroid colonies (E/G 3.5-5.1). When T-immunodeficiency is reversed with syngeneic lymphocytes, the differentiation of CFU is normalized at all stages of colony-formation. The process of differentiation of haemopoietic precursors, that form "early" and "late" colonies, is under T-lymphocyte control.

[Characteristics of the B lymphocytes participating in the reaction of allogeneic stem cell inactivation]. / Kharakteristika B-limfotsitov, uchastvuiushchikh v reaktsii inaktivatsii allogennykh stvolovykh kletok.

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.

[Effect of irradiation on the regulatory function of B-lymphocytes]. / Vliianie oblucheniia na reguliatornuiu funktsiiu B-limfotsitov.

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.

[Interaction of the lymph node and splenic lymphocytes of mice in inactivation of allogeneic hematopoietic stem cells]. / Vzaimodeistvie limfotsitov limfaticheskikh uzlov i selezenki myshei pri inaktivatsii allogennykh krovetvornykh stvolovykh kletok.

A study was made of interaction of mouse spleen and lymph node lymphocytes in inactivation of allogeneic stem cells. It was established that T lymphocytes of the lymph nodes and spleen lymphocytes do not interact on combined administration; their action is of additive nature. B lymphocytes of the lymph nodes have a regulating activity both in respect to T lymphocytes of the lymph nodes and lymphocytes of the spleen. The stem cells serve as target. Depending on the stem cells/B lymphocytes ratio B lymphocytes are capable of exerting either helper or suppressor action.

[Adaptive T-lymphocyte differentiation in an allogeneic environment]. / Adaptivnaia differentsirovka T-limfotsitov v allogennom okruzhenii.

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.

[Action of radiation on cell interactions in the phenomenon of nonsyngeneic stem cell inactivation. Quantitative parameters of the regulating effect of B-lymphocytes]. / Deistvie radiatsii ne kletochnye vzaimodeistviia v fenomene inaktivatsii nesingennykh stvolovykh kletok. Kolichestvennye parametry reguliruiushchego vliianiia B-limfotsitov.

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.

[Effect of radiation on cell interactions in the phenomenon of non-syngeneic stem cell inactivation. Changes in B-lymphocyte function after irradiation]. / Deistvie radiatsii na kletochnye vzaimodeistviia v fenomene inaktivatsii nesingennykh stvolovykh kletok. Izmenenie funktsii B-limfotsitov pri obluchenii.

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.

[Effect of thymectomy and syngeneic thymocytes on colony formation by hematopoietic precursor cells in the peritoneal cavity]. / Vliianie timéktomii i singennykh timotstiov na obrazovanie kolonii krovetvornymi kletkami-predshestvennikami v peritoneal'noi polosti.

The influence of the T-system of immunity on the processes of the proliferation and differentiation of hemopoietic precursor cells outside the organs of the hemopoietic and lymphoid systems has been studied. Thymocytes have been found to regulate the formation of hemopoietic foci in the peritoneal cavity. The effects of the stimulation and suppression of colony formation, as well as the degree of their manifestation, depend on the initial level of the colonies. The thymectomy of the recipients or donors of hemopoietic cells leads to the increase of colony formation. Syngeneic thymocytes abolish the effect of thymectomy.

[The effect of allogeneic lymphocytes on colony formation during culturing of hematopoietic precursor cells in the peritoneal cavity]. / Vliianie allogennykh limfotsitov na protsess kolonieobrazovaniia pri kul'tivirovanii krovetvornykh kletok-predshestvennikov v peritoneal'noi polosti.

The number of colonies formed in the peritoneal cavity (on the artificial underlayer made of peritoneal cells) and in the spleen of lethally irradiated recipients, (CBA X X C57BL) F1 mice, after the intraperitoneal injection of marrow cells depends on the cell donor's genotype: syngeneic cells and cells from mice of the parent strain CBA form fewer colonies in the peritoneal cavity than in the spleen, while cells from C57BL mice produce the reverse distribution of colonies between the peritoneal cavity and the spleen. Allogenic lymphocytes, when transplanted simultaneously with hematopoietic cells, suppress colony formation in the peritoneal cavity from day 2 of cultivation and eliminate the already developed foci of hematopoiesis by day 5.

[Factors that control the differentiation of stem cells. I. The change in direction of hematopoietic stem cell differentiation under the effect of differentiating T-lymphocytes]. / Faktory, kontroliruiushchie differentsirovku stvolovykh kletok. I. Izmenenie napravlenie differentsirovki stvolovykh krovetvornykh kletok pod vliianiem differentsiruiushchikh T-limfotsitov.

A mixed transplantation of bone marrow cells, and lymph nodes or thymic cells of mice CBA strain into lethally irradiated hybrid recipients (CBAXC57B1)F1 is accompanied with changes in the differentiation pattern from a mainly erythroid to a mainly granuloid way. Thymectomy of either donor of bone marrow cells or recipients, or both, destroys the stem cell differentiation in the direction of granulopoieseis. Intact syngeneic lymphocytes normalize differentiation of the stem cells, but in the presence of tissue antigens these provide for the stem cell differentiation mainly in the direction of granulopoiesis. The differentiation of stem haemopoietic cells is accomplished under the thymic and lymphocyte control. T-differentiating lymphocytes (Td) are the lymphocytes controlling the stem cell differentiation.

[Influence of the age of the recipient on the manifestation of the effect of allogeneic inhibition]. / Vliianie vozrasta retsipientov na proiavlenie éffekta allogennoi ingibitsii.

The expression of allogenic inhibition was studied when transplanting 10(5) cells of bone marrow of C57BL mice to the lethally irradiated recipients (CBA X C57BL) F1 of different age (2 to 11 months). In the control experiments the bone marrow cells at the same dose were introduced to the lethally irradiated syngenic (C57BL) mice. The most pronounced inhibition of the parental stem cells proliferation was registered in 2 months old recipients F1 (4.7 times), it was somewhat weakened in 3 months old and animal in 4--11 months old recipients (1.1 to 1.8 times). The thymectomy of adult recipients F1 did not eliminate the expression of allogenic inhibition.