Role of immune RNA in the interaction of T- AND B-lymphocytes]

"Immune" RNA preparations were obtained from the total population and also from the T- and B-lymphocytes of the spleens of the QBA line. Intact bone marrow cells or splenic cells activated with antigen served as target cells for the "immune" RNA. Investigations were carried out in the system of syngenic transfer. To study the target cells in the activated population of the spleen elimination of T-or B-lymphocytes was realized immediately after the incubation of the suspension of the splenic cells with the RNA preparations with the aid of anti-theta-or anti-B-antilymphocytic sera. T-lymphocytes served as the source of the biologically active RNA in the total preparation. B-lymphocytes of the spleen and the bone marrow served as target cells for the RNA of the cells of thymus origin. However, to detect the inducing action of the RNA simultaneous presence in the population of T- and B-lymphocytes is necessary.     

Lymphocyte subpopulations in sensitization and specific immunotherapy in an experiment. Lymphocyte subpopulations in sensitization to staphylococci, Artemisia pollen and their combinations

The distribution of T- and B-lymphocytes in the body of guinea pigs was studied in different groups of the animals. As shown in this study, in delayed hypersensitivity to staphylococci the number of PE- and E-rosette-forming cells increased in the blood, the spleen, and the lymph nodes and decreased in the thymus; the number of EA- and EAC-rosette-forming cells decreased in the bone marrow and the spleen, the number of T gamma-suppressors decreased in the bone marrow and the distant lymph node. Immediate hypersensitivity to tarragon pollen induced the general increase of the content of T- and B-lymphocytes; the number of T gamma-cells decreased in the thymus, the bone marrow, and the lymph nodes and increased in the spleen. The characteristic features of combined microbial-pollen sensitization were the high content of B-cells in all lymphoid organs (except the thymus), a low level of T-lymphocytes in the blood and the peripheral lymphoid organs, the decreased number of T gamma-cells in most of the immunogenetic organs.     

Stem cell, T- and B-lymphocyte migration in mouse lines that are high and low reactors to sheep erythrocytes]

Migration of stem cells and B-lymphocytes from the bone marrow and of T-lymphocytes from the thymus was studied on special models in mice of the CBA and C57BL lines, responding to sheep erythrocytes oppositely. Genetically-determined differences in the height of the immune response between the CBA and C57BL mice in immunization with sheep erythrocytes depended to a certain extent on different expression of the process of intensification of migration of the stem cells, T- and B-lymphocytes in response to the antigen administration.     

Immunologic competence of T- and B-lymphocytes in tolerance induced by cyclophosphamide]

A study was made of immunological competence of T- and B-lymphocytes of mice subjected to tolerogenic treatment (administration of a massive dose of sheep erythrocytes and cyclophosphamide 7 days before the experiment). The capacity of lymphocytes of tolerant mice to influence the interaction of normal T- and B-lymphocytes was also investigated. This form of tolerance was caused not by T-suppressors, but by a true deficiency of T-cells-helpers (both in the thymus and in the spleen), and partially of B-cells (in the spleen). Some lack of B-cells in the bone marrow was connected with a nonspecific action of cyclophosphamide. Cyclophosphamide is supposed to selectively eliminate cells proliferating in response to the antigen.     

Interaction and migration of T- and B-lymphocytes in immune responses during carcinogenesis induced by methylcholanthrene]

The (CBA X C57BL) F1 mice were injected intramuscularly with methylcholantrene (MCA) in a dose of 0.3 mg, and their T- and B-cells ability to cooperate in the immune response against sheep red blood cells, and also migration of these cells from the thymus and the bone marrow to the spleen were studied. The MCA immunosuppressive action proved to be associated with the inhibition of migration and cooperation of T- and B-lymphocytes in the immune response. A conclusion was drawn that the immunosuppressive effect developing during the carcinogenesis was complex and it was realized at various stages of immunogenesis.     

Immune suppression and histophysiology of the immune response

Seven daily intramuscular (im) injections of cortisone acetate (25 mg/Kg b.w.) given to rats or rabbits produced, (i) a pronounced reduction in the numbers of small lymphocytes in thymus-independent areas, (ii) atrophy of the thymic cortex, (iii) atrophy of germinal centres and (iv) a consequent depressed production of germinal centre-derived cells. Lymphocyte depletion was not caused by cell lysis. Moreover cell traffic between peripheral lymphoid organs did not seem to be altered. A revival of the depressed germinal centres in cortisone-treated (inbred) rats could be achieved by a transfer of bone-marrow cell suspensions from normal, cortisone-treated or T-cell-deprived animals. It was concluded that cortisone acetate arrests the migration of B-lymphocytes from the bone marrow to germinal centres in peripheral lymphoid organs, and that the accumulations of lymphoid cells in the bone marrow of cortison-treated animals might be composed of immature or mature T- and B-lymphocytes.     

Catalytic antibodies in the bone marrow and other organs of Th mice during spontaneous development of experimental autoimmune encephalomyelitis associated with cell differentiation

Exact mechanisms of autoimmune disease development are still yet unknown. However, it is known that the development of autoimmune diseases is associated with defects in the immune system, namely, the violation of the bone marrow hematopoietic stem cells (HSCs) differentiation profiles. Different characteristics of autoimmune reaction development in experimental autoimmune encephalomyelitis (EAE) prone Th mice characterizing T-lymphocytes response were analyzed using standard approaches. Profiles of several HSCs differentiation of bone marrow (BFU-E, CFU-E, CFU-GM, CFU-GEMM, T- and B-lymphocytes) of Th male and female mice during spontaneous development of EAE were noticeably different. Patterns of total lymphocytes, B- and T-cells proliferation in several different organs (bone marrow, blood, spleen, thymus, and lymph nodes) were also remarkably different. In addition, there were in time noticeable differences in their changes for some organs of male and female mice. Characters of changes in the profiles of CD4 and CD8 cells proliferation in some organs not always coincide with those for total T lymphocytes. The changes in the differentiation profiles of HSCs and the level of lymphocytes proliferation in the bone marrow and other organs were associated with the increase in the concentration of antibodies against DNA, myelin basic protein, and myelin oligodendrocyte glycoprotein, and catalytic antibodies hydrolyzing these substrates. Despite some differences in changes in the analyzed parameters, in general, the spontaneous development of EAE in male and female mice occurs to some extent in a comparable way.

     

Relationship between T- and B-lymphocyte cooperation and their syngeneity]

Cooperation efficiency of (CBA x C57BL/6) F1 thymocytes and CBA bone marrow cells in immune response to SRBC was compared with the syngenic combination of the same cells. Selectivity of interaction of the T- and B-lymphocytes of different origin was studied in incomplete cyclophosphamines (CBA x C57BL/6) leads to CBA chimerae, where donors were primed with SRBC and the recipients were either intact or tolerant to the given antigen. F1 T-cells proved to interact with the CAB-B-cells 10-15 times less effectively than with the syngenic B-cells. It is suggested that similarity between the antigenic structure of the cell membrane of the T- and B-lymphocytes, aiding their physical contact, increased the action efficiency of the T-mediator on the B-cell.     

Change in the cooperation of T- and B-lymphocytes during the immune response of ram erythrocytes in the presence of liver injury by carbon tetrachloride

Changes in cooperation of T- and B-lymphocytes induced by the immune response to the ram erythrocytes under conditions of liver injury by CCl4 in donors of cells or recipients have been studied on CBA line mice in the adaptive transfer system. It is stated that application of CCl4 induces changes in functional properties of T- and B-lymphocytes and process of their cooperation. The pattern of these changes is determined by periods passed after application of the hepatotropic poison, e. i. by the degree of the liver injury and by the stage of the pathological process in it. Application of CCl4 exerts more pronounced inhibiting effect on B-lymphocytes than on T-lymphocytes.     

Temporary characteristics of the process of stem cell inactivation by allogenic lymphocytes]

The time during which transplated lymphocytes block proliferation and differentiation of non-syngeic stem cells has been determined by retrasplantation of immuno-competent cells from one lethally irradiated recipient to another one. It was established that process of inactivation of CFU by allogeneic lymphocytes proceeds itwo stages. At the first stage, the colonization of recipient's tissues takes place. The colonization of tissues and processes of early recognition are completed during the first hours after transplantation of cell mixtures. At the second stage, the processes of redistribution of injected cells occur and a complete inactivation of stem cells take place. These events are completed in bone marrow and spleen 4-5 days after transplantation of cells mixture, possibly with the participation of lymphocytes sensibilized with the target-cells.     

The functional condition of the immune system and the lymphocytes' hemopoiesis-modulating properties

Donor splenocytes and timocytes have an ability to stimulate erythropoesis after massive blood-letting. Changing of functional state of the immune system by means of immune modulators action affects the character and expressiveness of hemopoiesis regulation function of lymphocytes. Splinocytes and thymocytes depress granulocytopoiesis in the recipients' bone marrow after activation by T- and B-lymphocytes. The activation of B-lymphocytes determines the cells' capacity to increase concentration of thrombocytes in the blood. Donor thymocytes can activate erythropoiesis and granulocytopoiesis after macrophages stimulation.     

Generation of osteoclasts from hemopoietic cells and a multipotential cell line in vitro

Osteoclasts are the cells that resorb bone. It is generally presumed, on the basis of indirect experiments, that they are derived from the hemopoietic stem cell. However, this origin has never been established. We have developed an assay for osteoclastic differentiation in which bone marrow cells are incubated in liquid culture on slices of cortical bone. The bone slices are inspected in the scanning electron microscope after incubation for the presence of excavations, which are characteristic of osteoclastic activity. We have now incubated bone marrow cells at low density, or a factor-dependent mouse hemopoietic cell line (FDCP-mix A4) with 1,25 dihydroxyvitamin D3 (a hormone which we have previously found induces osteoclastic differentiation) with and without murine bone marrow stromal cells, or with and without 3T3 cells, on bone slices. Neither the bone marrow cells nor the bone marrow stromal cells alone developed osteoclastic function even in the presence of 1,25 dihydroxyvitamin D3. However, extensive excavation of the bone surface was observed, only in the presence of 1,25 dihydroxyvitamin D3, on bone slices on which bone marrow stromal cells were cocultured with low-density bone marrow cells or the hemopoietic cell line. Similar results were obtained when the bone marrow stromal cells were killed by glutaraldehyde fixation; 3T3 cells were unable to substitute for stromal cells. These results are strong evidence that osteoclasts derive from the hemopoietic stem cell and suggest that although mature osteoclasts possess neither receptors for nor responsiveness to 1,25 dihydroxyvitamin D3, the hormone induces osteoclastic function through a direct effect on hemopoietic cells rather than through some accessory cell in the bone marrow stroma. The failure of 3T3 cells, which enable differentiation of other hemopoietic progeny from this cell line, to induce osteoclastic differentiation suggests that bone marrow stroma possesses additional characteristics distinct from those that induce differentiation of other hemopoietic cells that are specifically required for osteoclastic differentiation.     

Evidence for the presence of precursor B cells in normal and in hormonally bursectomized chick embryos

Embryonic bone marrow of normal and hormonally bursectomized chicks was examined for the presence of hematopoietic precursor cells capable of migrating to the thymus and bursa and of differentiating into functional T and B cells, respectively. Following transfer of chromosomally marked bone marrow of normal and in ovo bursectomized 14-day-old embryos to 14-day-old γ-irradiated embryonic recipients, donor cells proliferated in the marrow, thymus, and bursa of recipients, and differentiated to PHA- and Con A-responsive T cells as well as to dextran sulfate- and anti-immunoglobulin-responsive B cells. In contrast, when marrow of 2-day-old hatched normal and in ovo-bursectomized donors was transferred to 14-day-old embryonic recipients, donor cells repopulated only the marrow and thymus of recipients which was followed by differentiation to Con A- or PHA-responsive T cells, but the same donor cells failed to proliferate in the bursa and there was no differentiation to functional B cells of donor type. The data were fitted to a model of T- and B-cell differentiation from the stem cell level and they suggest the presence of separate populations of committed precursor T (PT) and precursor B (PB) cells in the marrow of normal and in ovo bursectomized embryos with a bursa-independent selective disappearance of PB cells from the marrow during the late embryonic period.     

Levels of uracil DNA glycosylase and AP endonuclease in murine B- and T-lymphocytes do not change with age

Two DNA repair enzyme activities, uracil DNA glycosylase and AP endonuclease, were measured in extracts of T- and B-lymphocytes isolated from mice ranging in age from 3 to 24 months. T- and B-lymphocytes had roughly equal levels of AP endonuclease which did not change appreciably with age. T-lymphocytes had roughly twice as high a level of uracil DNA glycosylase as B-lymphocytes; these levels were not affected by age either. This constancy with age contrasts dramatically with increases in both enzymes--roughly 3-fold on a protein basis or 50-fold on a per cell basis--in a transformed line (MPC-11) derived from a carcinogen-induced lymphocytoma. These results are similar to those obtained with cultured murine fibroblasts, wherein a relative constancy was noted with passage of non-transformed cells, followed by dramatic changes upon transformation (La Belle, M & Linn, S, Mutat res 132 (1984) 51). Hence these enzyme assays do not support the notion of a drop in base excision DNA repair capacity as being a causative factor in aging, but suggest instead that DNA repair properties might differ dramatically in transformed vs non-transformed cells.     

The effect of haemopoietic stem cell proliferation on the humoral immune response in mice

Abstract A study was made of the effect of humoral factors, isolated from bone marrow cell (BMC) supernatant fluid and capable of modifying CFU-S proliferation, on the generation of IgM plaque-forming cells (PFC) against sheep red blood cells (SRBC) in mice after adoptive transfer. Adoptive transfer of BMC, preincubated with the humoral factor RBME-III, which stimulates CFU-S proliferation, was shown to suppress the splenic PFC generation in recipients; treatment of BMC with a further factor NBME-IV, which inhibits CFU-S proliferation, was followed by augmentation of PFC generation. Similar effects were obtained while studying the IgM PFC generation in the bone marrow of mice after secondary immunization when relevant factors were injected, in vivo , 24 hr following primary immunization. The results of adoptive transfer experiments indicate that populations of T- and B-cells are not the targets for the action of CFU-S proliferation regulatory factors. These factors are shown to modulate the erythroid differentiation of CFU-S. The possibility of quantitative modification of immune response parameters with the help of bone marrow factors that influence the proliferation and differentiation of CFU-S is discussed.     

The effect of haemopoietic stem cell proliferation on the humoral immune response in mice

A study was made of the effect of humoral factors, isolated from bone marrow cell (BMC) supernatant fluid and capable of modifying CFU-S proliferation, on the generation of IgM plaque-forming cells (PFC) against sheep red blood cells (SRBC) in mice after adoptive transfer. Adoptive transfer of BMC, preincubated with the humoral factor RBME-III, which stimulates CFU-S proliferation, was shown to suppress the splenic PFC generation in recipients; treatment of BMC with a further factor NBME-IV, which inhibits CFU-S proliferation, was followed by augmentation of PFC generation. Similar effects were obtained while studying the IgM PFC generation in the bone marrow of mice after secondary immunization when relevant factors were injected, in vivo, 24 hr following primary immunization. The results of adoptive transfer experiments indicate that populations of T- and B-cells are not the targets for the action of CFU-S proliferation regulatory factors. These factors are shown to modulate the erythroid differentiation of CFU-S. The possibility of quantitative modification of immune response parameters with the help of bone marrow factors that influence the proliferation and differentiation of CFU-S is discussed.     

Structure and function of bone marrow environment

Bone marrow and spleen are the major hematopoietic tissue in adult mice. However, little is known about the specific mechanism regulating hematopoiesis within these tissues. Since Dexter et al. first described conditions to maintain bone marrow hematopoiesis, long term bone marrow culture (LTBMC) has been developed in order to analyze the mechanism of the maintenance of proliferation and differentiation of hematopoietic stem cells in vitro. Furthermore, several stromal cell lines which are able to support the growth and differentiation of hematopoietic lineage, has been established from LTBMC. Although it is well known that bone marrow stromal cell lines are able to produce colony stimulating factors, it has been suggested that the stromal cell factors which involve membrane bound moieties must have a key role in the regulation of hematopoiesis. We expect that monoclonal antibodies to the surface of bone marrow stromal cells could detect such a critical stroma-associated protein that bounds the cell surface of the bone marrow stroma.     

Mechanism of the adjuvant action: effect on the stem cell and B-lymphocyte migration from the bone marrow]

The authors studied the influence of synthetic polyelectrolytes of polyacrylic acid and poly-2-methyl-5-vinylpyridine and of complete Freund's adjuvant on the migration of stem cells and B-lymphocytes from mouse bone marrow. The stem cell count was evaluated by the number of splenic colonies; as to B-cell migration--it was assessed by the accumulation of the antibody-forming cells forming from B-lymphocytes migrating in the spleen in the transfer of fixed number of T-lymphocytes. As revealed the synthetic substances under study intensified the migration of stem cells and of B-lymphocytes to a much greater extent than Freund's adjuvant. The mechanisms of the influence of the adjuvants used on cell migration processes are discussed.