Suppression by bone marrow cells of the level of specific IgE antibodies in the blood of mice and decrease in the production of IGE by bone marrow cells

Changes in the level of the specific IgE-antibodies to ovalbumin under the influence of syngeneic cells of a bone marrow were studied. The IgE-response was induced by ovalbumin in mice (CBA X C57Bl/6)F1. The bone marrow cells suspensions (20-30 X 10(6) cells per mouse) from syngeneic donors was inoculated simultaneously with the immunization. It was found that bone marrow cells suppressed both the level of IgE-antibodies in experimental mice serum and the production of IgE by the bone marrow cells of the recipient. The ability to suppress IgE-response remained when erythrocytes, monocytes and T-lymphocytes were removed from inoculated suspensions. The bone marrow cells taken from the mice immunized with ovalbumin, at the stage of a decreasing IgE-response, provided more pronounced suppression, than bone marrow cells taken from intact animals.     

Changes in the nature of the differentiation of the erythroid stem cell in the bone marrow of mice as affected by the peritoneal cells of donors subjected to bloodletting

The influence of the peritoneal cells unstimulated by an inflammatory agent (PCs) on the bone marrow erythropoiesis in the CBA mice was studied in the normal conditions and after the massive haemorrhage. The PCs obtained from the intact or anemic donors (2, 4 and 18 h after the haemorrhage) were introduced intraperitoneally into the intact syngeneic recipients. The massive haemorrhage induces a special type of differentiation of erythroid cells in bone marrow, "reserve erythropoiesis", which is characterized by a decrease, within four days, in the proliferation of basophilic proerythrocytes, stimulation of proliferation of polychromatophilic proerythrocytes and entry of oxyphilic proerythrocytes into mitosis. The transplantation of the PCs from the anemic donors induced the "reserve erythropoiesis" in the bone marrow of the recipients. The transplantation of the PCs from the intact donors did not induce the "reserve erythropoiesis" and appeared to inhibit erythropoiesis via lengthening the time of mitoses in polychromatophilic and basophilic proerythrocytes.     

Modeling of the "universal" bone marrow using monoclonal antibodies

The data on the application of monoclonal antibodies (ICO-10) and rabbit complement for working the conditions of allogeneic bone marrow transplantation are presented in the paper. The treatment with monoclonal antibodies and bone marrow complement from BALB/c mice for 2 times prevented the development of transplant versus host reaction and completely protected lethally irradiated (CBA X X C57B1/6)FI mice-recipients from death. Thymus atrophy and the absence of T-cells in the peripheral blood was observed in these mice. The erythrocytes had markers characteristic of BALB/c and (CBA X C57B1/6)FI mice. Mouse splenocytes did not respond to the cells of donors and recipients in mixed lymphocyte culture reaction.     

The origin of antibody-forming cells detected in the bone marrow after thymus-independent antigen-stimulation and abnormality in migration of B cells of X-linked immunodeficient CBA/N mice

The anti-TNP IgM plaque-forming cells (PFC) were generated in the spleen and bone marrow of non-immunodeficient normal mice after intraperitoneal administration of TNP-LPS. Irradiation of normal mice while shielding bone marrow completely abrogated the generation of bone marrow PFC, indicating that they are derived from extramedullary sites. The bone marrow PFC, response to TNP-LPS was low in X-linked immunodeficient CBA/N strain mice, while the spleen response was comparable to that seen in the normal mice. To further study the basis of the deficient bone marrow PFC response in CBA/N mice, spleen cells were adoptively transferred to irradiated syngeneic mice stimulated with TNP-LPS. While spleen cells from normal mice generated high numbers of PFC in recipient bone marrow and spleen, those from CBA/N strain mice could not generate bone marrow PFC. This result was obtained regardless of whether normal or CBA/N recipients were used. These results indicate that TNP-LPS administration normally results in the migration of B lymphocytes from the periphery into the bone marrow and that B cells from immunodeficient CBA/N strain mice bear an inherent defect in this migratory function. This migratory defect was shown to be X-linked, as are the other previously reported B cell defects in this inbred mouse strain. The possible relationship between this migratory defect and the maturational defects of B cell lineage as reported previously in CBA/N strain mice is discussed.     

Hybrid resistance to precursor cells of bone marrow stroma]

A focusl of hemopoiesis appearing after the transplantation of a bone marrow fragment of C57BL mice to syngeneic mice (under the kidney capsule) contained more hemopoietic cells than in transplantation to the semisyngeneic (CBA X C57BL) FI recipient. Experiments were conducted with a secondary seeding by intravenous injection of hemopoietic cells of the C57BL transplant genotype into the transplant depopulated by irradiation; it was shown that these differences were caused by lesser dimensions of the hemopoietic microenvironment in the focus in the hybrid organism in comparison with such in the syngeneic system. Thus, the hybrid resistance was expressed not only to the hemopoietic cells, but also to the stromal precursors transferring the hemopoietic microenvironment.     

B-cell suppression of antibody response to sheep red blood cells in mice of high- and low-responding genotypes.

CBA and C57B1 mice (high and low responders to sheep red blood cells, respectively) were injected intravenously with syngeneic lymph node, marrow, spleen, or thymus cells together with sheep red blood cells (SRBC), and the production of antibody-forming cells (AFC) was assayed in the spleen. Transfer of lymph node, marrow, spleen, or thymus cells led to a significant enhancement of immune responsiveness in low-responding C57B1 mice. In contrast, transfer of marrow, lymph node, or spleen cells to high-responding CBA mice was accompanied by a decline in AFC production. These effects were magnified if syngeneic cell donors had been primed with SRBC; suppression in CBA mice and stimulation in C57B1 mice were especially pronounced after transfer of SRBC-primed lymphoid cells. Pretreatment of CBA donors with cyclophosphamide in a dose causing selective B-cell depletion completely abrogated the suppression of immune responsiveness. A large dose (10⁷) of syngeneic B cells injected together with SRBC suppressed the accumulation of AFC in both CBA and C57B1 mice. No suppression of immune responsiveness was observed after transfer of intact thymus cells, hydrocortisone-resistant thymocytes, or activated T cells. We conclude that suppression of the immune response to SRBC is induced by B cells. At the same time, there is a possibility that the addition of “excess” B cells acts as a signal, triggering suppressor T cells.     

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]

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.     

Genetics of resistance to the African trypanosomes. IV. Resistance of radiation chimeras to Trypanosoma rhodesiense infection

The cellular bases of resistance to the African trypanosomes were examined in inbred mice. As part of these studies, reciprocal bone marrow cell transplants were performed between H-2 compatible mice which differ in relative resistance to Trypanosoma brucei rhodesiense infection. Survival times, parasitemias and IgM antibody responses to the surface antigen of the infecting variant type were measured in these semiallogeneic bone marrow chimeras. Relatively resistant C57BL/10 mice, intermediate A.By mice, and least resistant C3H.SW mice that were reconstituted after lethal irradiation with syngeneic bone marrow cells displayed resistance and immunity characteristic of the homologous donor strain. When C57BL/10 mice were reconstituted with C3H.SW mouse bone marrow cells they retained the ability to produce antibodies to trypanosome surface antigen but the antibody titers were significantly reduced. Control of parasitemia and mean survival time were reduced in these chimeras, but differed significantly from C3H.SW mice. A.By mice that received cells from C57BL/10 donors exhibited antibody responses and survival times similar to the C57BL/10 mice. Survival times of A.By mice given syngeneic cells or C3H.SW cells were the same, but the antibody responses of A.By mice given C3H.SW cells were lower than those of A.By mice given syngeneic cells. C3H.SW mice reconstituted with C57BL/10 bone marrow cells were capable of making antibodies and controlling parasitemia, in marked contrast to the absence of such responses in C3H.SW mice reconstituted with syngeneic cells. Survival times, however, were indistinguishable from those of C3H.SW mice given syngeneic cells. Thus, resistance to T. b. rhodesiense was shown for the first time to depend on donor bone marrow derived cells as well as upon radiation-resistant cells/factors associated with host genetic background. Also, parasite-specific IgM antibody responses seem to be regulated by a mechanism which does not depend on bone marrow derived cells alone, and the presence of such immune responses is not linked to survival time.     

Thymus-dependence of genetic resistance to (CBA x M523)F1 lymphocytes

The nature of cells responsible for the genetic resistance of lethally irradiated CBA mice to lymphocytes of (CBA x M523)F1 hybrids was studied. Preirradiation of the hosts was shown to abolish the resistance. The latter was generally recovered by syngeneic thymocytes or splenocytes while embryonic liver and bone marrow cells or splenocytes treated with anti-Thy-I serum plus complement before injection into host were ineffective. It is postulated that some cells with T cell characteristics are responsible for the phenomenon of parental resistance. These cells differ in several respects from T cells that mediate the transplantation immunity and from M cells that control other forms of the genetic resistance.     

The structural-functional organization of the bone marrow after lethal irradiation and the transplantation of syngeneic hematopoietic cells]

A study was made of the content and morphology of haemopoietic islands in the bone marrow of lethally irradiated CBA mice, and their change after transplantation of syngeneic haemopoietic cells. The data obtained show that the haemopoietic islands are reconstructed in the injured haemopoietic tissue due to the donor's bone-marrow nuclears. A new type of structural and functional associations, namely, stromal haemopoietic islands, has been found.     

Influence of the maternal effect on allogenic inhibition of hematopoietic stem cells]

Bone marrow cells (0,5-10(6)) of female mice of CBA or C57BL strains were injected intravenously to lethally irradiated CBA, C57BL/6, (femaleCBA X maleC57BL/6)F1 and (femaleC57BL/6 X maleCBA)F1 mice. Spleen of recipients as assayed for colony count on the 9th day after bone marrow transplantation by the method of Till and McCullouch. Stem cells of CBA mice demonstrated failure of allogenic inhibition in (CBA X C57BL/6)F1 hybrid mice and formed the same number of colonies as in the spleen of syngenic recipients. The level of allogenic inhibition of CBA stem cells transplanted to (C57BL/6 X X CBA)F1 hybrid mice was 50%. Bone marrow cells of C57BL/6 mice formed colonies in spleen of (CBA X C57BL/6)F1 mice at least in 20 times less than in syngenic combination. In the transplantation of bone marrow from C57BL/6 mice to (C57BL/6 X CBA)F1 hybrid mice the allogenic inhibition was less pronounced (77-85%) as compared with the transfer of cells to (CBA X C57BL/6)F1 hybrid mice (95%). The sex of a recipient did not influence the number of formed colonies. The different level of allogenic inhibition of parental stem cells can not be explained by the effect of linkage with sex as the female of reciprocal hybrid mice have identical structure of sex chromosomes (X(CBA)XC57BL/6). The data obtained indicate that the maternal effect affects allogenic inhibition of stem cells in parent--F1 system. It is possible that the maternal influence may be determined by cytoplasmic factors of inheritance which affect the expressivity of recessive genes Hh, controlling the inheritance of specific haematopoietic cell antigens.     

Marked difference in sensitivity to gamma-ray-induced cataract between BALB/c and CBA-C3H strain mice]

Nineteen BALB/c, 14CBA/KI, 12C3H/HeJ and 15 (CBA/Kl x C3H/HeJ) F1 female mice were irradiated with 850 rad gamma-rays and transferred with 10(7) syngeneic bone marrow cells 24 hrs later. The occurrence of cataract was examined in these animals. All the BALB/c mice showed visible lens opacification in both eyes between 113 and 149 days after irradiation. All the animals were autopsied 6 months after irradiation and examined for opacification of their lenses. The proportion of opaque lenses was 100, 7.1, 16.7 and 0% in BALB/c, CBA/Kl, C3H/HeJ and (CBA/Kl x C3H/HeJ) F1 mice, respectively. The results indicate that BALB/c mice are much more sensitive to radiation-induced cataractogenesis than CBA and C3H mice.     

An apparent discrepancy between the number of colony forming units transplanted and survival of busulphan lethally treated rats

Conditions for keeping busulphan lethally treated rats alive by transplantation of bone marrow cells from syngeneic donors are described. After busulphan treatment of the donor rats with a dose which only reduces the colony forming units (CFU's) in the marrow (assayed by the spleen colony technique) to half the normal numbers, at least 100 times as many cells from these treated donors, compared to untreated rats, are required to produce an equivalent increase in survival of busulphan lethally treated recipients. In contrast, aminochlorambucil, despite producing a marked fall in bone marrow cellularity, has no effect on the number of CFU/femur, yet the marrow from these aminochlorambucil treated donors is no more effective in increasing the survival of busulphan lethally treated recipients than untreated marrow. Theories which may explain this apparent discrepancy and evidence which it affords on the mode of action of busulphan are discussed.     

Effect of a deficiency in the mononuclear phagocyte system and the administration of yeast polysaccharide on the development of a heterotopic source of hematopoiesis

Mononuclear phagocyte system (MPS) deficiency was induced by repeated peritoneal lavage in (C57Bl x CBA) F1 mice. The animals were then used as donors or recipients in heterotopic bone marrow transplantation. Yeast polysaccharide (YP) produced by Cryptococcus luteolus strain 228 was injected weekly (25 mg/kg) during 30 days after bone marrow transplantation under the kidney capsule. Bone marrow transplantation from MPC-deficient mice to intact mice 30 days later resulted in no variations from the control in cellularity and ossicle weight. YP produced an increase in cellularity, but not in ossicle weight. In the opposite experimental scheme (transplantation from intact mice to MPS-deficient mice) an increase in both cellularity and weight was not noticed. YP injections in this case resulted in the reduction of heterotopic organ size to the control level. Possible mechanisms of this phenomenon are discussed.     

MULTIPLICATION OF HAEMOPOIETIC COLONY FORMING UNITS (CFU) IN MICE AFTER X-IRRADIATION AND BONE MARROW TRANSPLANTATION

Kinetics of the multiplication of haemopoietic CFUs was studied in lethally irradiated mice receiving various numbers of syngeneic bone marrow cells. After transplantation of a small number of bone marrow cells, the growth rate of CFU in femoral bone marrow appeared to decrease after about 10 days after transplantation, before the normal level of CFU in the femur was attained. In the spleen it was found that the overshoot which was observed about 10 days after transplantation of a large number of bone marrow cells is smaller or absent when a small number of cells is transplanted. Experiments dealing with transplantation of 50 x 10⁶ bone marrow cells 0, 4 or 10 days after a lethal irradiation indicated that the decline in growth rate of CFUs about 10 days after irradiation could not be attributed to environmental changes in the host.
The results are explained by the hypothesis that a previous excessive proliferation of CFUs diminishes the growth rate thereafter. This hypothesis is supported by experiments in which 50 x 10⁶ bone marrow cells derived from normal mice or from syngeneic chimaeras were transplanted. The slowest growth rate was observed when bone marrow that had been subjected to the most excessive proliferation in the weeks preceding the experiment was transplanted.     

Chromosomal abnormalities and spleenocyte production in laboratory mouse males after exposure to stress chemosignals

Activity of antibody producing spleenocytes and chromosome stability in bone marrow cells from laboratory mouse males of CBA strain after exposure to different chemosignals excreted by stressed or irradiated syngeneic donors was studied. It has been shown that the exposure of the recipient males to volatiles from donor males (stressed by swimming) decreases quantity of antibody-producing cells in 1, 3 and 10 days after the treatment. The same exposure increased the chromosome aberrations level in dividing bone marrow cells from CBA recipients in 1 day after the treatment. Similar changes were observed in 24 h after exposure to volatiles of irradiated donors or to synthetic mouse pheromone, 2,5-dimethylpyrazine. Possible mechanisms of chemosignals effect on the immune system are discussed.     

Changes in the H-alloantigen-recognizing function of mouse lymphoid cells following hydrocortisone administration]

The capacity of spleen, thymus, and bone marrow cells of intact (control) and of hydrocortisone-treated mice CBA to induce the lymph node type of graft-v-host reaction (GVHR) in hybrids F1 (CBA X c57bl) was studied. After hydrocortisone injection (2.5 mg per mouse) the donor spleen cells became more active in GVHR, considering the value of lymph node indices and immunoblast content in the regional lymph node as compared with a control group. Following transplantation of thymus cells taken from the hydrocortison-treated donors the immunoblast count was higher, although the lymph node weight remained the same as in the control group. On the contrary, following the transfer of the bone marrow cells from the hydrocortisone-treated mice the lymph nodes enlarged, while the immunoblast count remained as low as in control. Consequently, exogenously conditioned increase in the hydrocortisone level was accompanied by an enrichment of the spleen and thymus cell populations with T-lymphocytes, proliferating in response to H-alloantigens.     

The effect of bone marrow transplantation on the dynamic recovery of the morphofunctional properties of the pancreas in irradiated recipients

Effect of transplantation of syngeneic bone marrow in the dose of 1 X 10(7) cell/ml on the state of pancreatic gland in lethally irradiated recipients has been studied at different stages of posttransplantation period for 3 months using 250 linear male rats G (CBA x C57B). Histological and biochemical investigation, conducted in dynamics, have shown that transplantation of native and cryopreserved bone marrow to lethally irradiated animals facilitates activation of compensatory-restoration processes manifesting themselves in mitotic division of glandular and epithelial cells, as well as optimizes exchange of carbohydrates in the irradiated organism.     

Effect of tissue macrophage destruction products on hematopoietic stem cells]

Products of mouse peritoneal macrophage destruction (PMD) obtained by aseptic freezing-thawing of the cells, repeated thrice, were found to elicit in syngeneic mice injected with PMD intraperitoneally an increase of CFUs count in the hemopoietic bone marrow tissue and the spleen, as demonstrated by the Till and McCullooch technique. This proved to be a true increase since the transplatned stem cell fraction sorbed by the recipient's spleen was relatively lower in donor mice given PMD than in the control. Although PMD caused an increase of both erythropoietic (E) and granulocytopoietic-monocytic (G) colonies number, the E/G ratio was decreased; one of the mechanisms of the described effect could be the influence of PMD on the hemopoiesis-inducing microenvironment, as the same effects were obtained in mice injected repeatedly with PMD prior to the transplantation of bone marrow tissue of normal donors. Other possible mechanisms of these effects were analyzed, with consideration to the fact that in experiments with preincubation of bone marrow tissue with PMD prior to injection to the lethally irradiated mice no direct stimulating influence of PMD on the stem cell could be revealed.     

Bone marrow-derived T lymphocytes responsible for allograft rejection

Lethally irradiated mice reconstituted with syngeneic bone marrow cells were grafted with allogeneic skin grafts 6-7 weeks after irradiation and reconstitution. Mice with intact thymuses rejected the grafts whereas the mice thymectomized before irradiation and reconstitution did not. Thymectomized irradiated mice (TIR mice) reconstituted with bone marrow cells from donors immune to the allografts rejected the grafts. Bone marrow cells from immunized donors, pretreated with Thy 1.2 antibody and C', did not confer immunity to TIR recipients. To determine the number of T lymphocytes necessary for the transfer of immunity by bone marrow cells from immunized donors, thymectomized irradiated mice were reconstituted with nonimmune bone marrow cells treated with Thy 1.2 antibody and C' and with various numbers of splenic T lymphocytes from nonimmune and immune donors. Allogeneic skin graft rejection was obtained with 10(6) nonimmune or 10(4) immune T cells. The effect of immune T cells was specific: i.e., immune T cells accelerated only rejection of the relevant skin grafts whereas against a third-party skin grafts acted as normal T lymphocytes.