Increase in the number of antibody producing cells during combined cultivation of lymph node cells from immunized animals with intact bone marrow cells]

An increase in the amount of direct and indirect plaque-forming cells in mixed cultures of lymph node cells from mice primed and challenged with sheep red blood cells with syngenic and allogenic bone marrow cells from intact donors was observed. The amount of plaque-forming cells in mixed cultures reached the maximum level in 9--11 hours of cultivation and then fell to the initial level. The authors believe that in mixed cultures of lymph node cells from immune mice and bone marrow cells from intact donors there occurs an involvement into the antibody synthesis of new cells of one of the two cell populations cultured.     

Replacement of the helper function of T cells by an RNA-containing antigen-specific lysis factor]

The lymph node viable cells suspension of immunized mice was centrifugated. The supernatant was chromatographed in Sephadex G-200, and fractions were deproteinized. The deproteinized third fraction (Mol wt 30000) stimulated specifically the plaque-forming cells of intact mice immunized by SRBC. It restored the capacity to antibody production in the lethally irradiated intact mice protected by the syngeneic bone marrow. The activity of this fraction disappeared following treatment with RNA-ase, but not with DNA-ase or trypsin. The first and the second deproteinized fractions of the supernatant inhibited non-specifically the viable lymph node cells of the immunized animals in the intact mice immunized with SRBC.     

The nature of the factors in immune lymph nodes that stimulate humoral and cellular immune reactions

In the early period after antigen action, cells of the lymph node draining area of antigen injection produce a factor, which after its administration to intact mice, promotes intensified migration of myelopeptide producers in the bone marrow and increases bone marrow suppressor activity. Factor administration produced 2-3-fold increase in macrophage, peritoneal and lymph node count as compared with control, and 2-4-fold increase in humoral and cellular immune response. The factor consists of three easily identifiable components: Ig, MHC class II determinants and antigen determinants, that form unique complex similar to, or identical with the complexes detected in vivo within 3-6 hours after immunization in serum by other authors.     

Failure of ovalbumin associated with allogeneic spleen ceels to stimulate proliferation of lymph node cells of immune mice.

Ovalbumin-pulsed spleen cells were found to stimulate thymidine uptake of lymph node cells of syngeneic mice immunized with ovalbumin in complete Freund's adjuvant after treatment of spleen cells with Mitomycin C but not after heating the spleen cells at 56degrees for 30 min. Ovalbumin-pulsed spleen cells of allogeneic mice failed to stimulate the immune lymph node cells more than unpulsed cells, although a net increase in the thymidine uptake above the allogeneic stimulation was observed when free ovalbumin was added to the mixed culture. To eliminate the high background of the mixed lymphocyte reaction, F1 mice were made chimeric with bone marrow of one of the parental strains. Using lymph node cells of the immunized chimeras, the stimulation by pulsed spleen cells was much greater when antigen was presented on cells of the parental strain used for bone marrow injection than when presented on cells of the other parental strain.     

种间胚胎植入对母体免疫系统T细胞比例的影响

目的:研究种间胚胎植入期母体外周血、外周免疫器官(淋巴结、脾脏)、中枢免疫器官(胸腺、骨髓)中总T细胞的百分比变化,并探讨这种变化对种间胚胎植入的影响.方法:利用荧光标记的单克隆抗体染色结合流式细胞术,检测种间、同种胚胎移植以及同期假孕母体外周血、淋巴结、脾脏、胸腺、骨髓中T淋巴细胞的百分率.结果:种间胚胎植入时其外周血T细胞计数极显著低于同种和同期假孕小鼠(P＜0.01),而淋巴结、胸腺、骨髓中的T细胞计数则极显著高于同期假孕小鼠(P＜0.01).脾脏中同种胚胎植入母体则极显著高于种间和同期假孕小鼠(P＜0.01),两后者之间无显著性差异(P＞0.05).结论:种间妊娠时早在植入期开始,母体全身免疫系统就开始发生不利于种间妊娠的反应.     

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.     

Inhibition of erythroid cell growth by allogeneic murine lymphocytes. Evidence for a synergism between lymph node cells and thymocytes

Murine lymphoid cells from thymus and lymph nodes were tested for synergistic response in a graft-vs-host test. The test is based on the principle that allogeneic lymphocytes inhibit erythroid cell proliferation in the spleens of irradiated mice infused with syngeneic bone marrow cells.I was observed that mixtures of thymocytes and lymph node cells from the same parental strain yielded graft-vs-host responses in irradiated F₁-hybrids higher than expected by summing the responses of the two cell populations tested separately. A similar synergistic response was obtained using mixtures of thymocytes and lymph node cells obtained from the two parental strains of the hybrid, whereas such an effect was not detected using mixtures of lymph node cells or mixtures of thymocytes from the two parental strains. Nor could synergy be demonstrated between parental strain lymph node cells and thymocytes syngeneic with the bone marrow target cells. Thymocytes obtained from one parental strain which were injected into its irradiated F₁-hybrid transformed into a population of sensitized cells in the spleens of the recipients. This transformation was suppressed by the simultaneous injection of lymph node cells from the second parental strain. Since there is a synergistic immune response by such cell mixtures it is concluded that thymocytes may enhance the graft-vs-host response of lymph node cells. Parental strain thymocytes and lymph node cells, the latter being specifically immunologically tolerant to the bone marrow target cells, failed to give a synergistic response indicating that thymocytes do not transform unresponsive lymphocytes into responsive, but rather enhance the reactivity of existing, specifically responsive cells.The results thus show that thymocytes may enhance the response of lymph node cells in this specific graft-vs-host assay.     

Elevated cyclic AMP levels in mouse lymphoid tissue after stimulation by cholera enterotoxin in vitro (38468)

Addition of CT to suspensions of thymus, lymph node, spleen, or bone marrow cells in vitro resulted in a marked accumulation of cAMP with peak levels occurring 4-5 hr after incubation of cells with CT. Thymus cells showed the largest increase in cAMP, approximately 40-fold at 10 ng/ml CT. Bone marrow cells accumulated the least cAMP (1.5x), while intermediate levels were observed for spleen and lymph node cells (10-12x). Antiserum to CT prevented stimulation of increased cAMP levels. Repopulation studies using X-irradiated mice also showed that thymus-derived spleen cells accumulated more cAMP/10-7 cells than spleen cells from recipients given spleen or marrow cells. Spleen cells from athymic (nu/nu) mice also responded much less than did spleen cells from normal mice. Thymocytes appeared to bind CT to a greater degree than bone marrow cells. Spleen and lymph node cell suspensions also contained CT-binding cells and the number of CT-binding cells in these peripheral lymphoid tissues appeared approximately equal to the summation of the numbers observed in thymocyte and bone marrow cell suspensions. Stimulation of cAMP in lymphoid cells, especially thymocytes, by CT provides a pharmacological tool to investigate the mechanism and role of this nucleotide in the early events of antibody formation.     

Nature of the target cells in bone marrow B-suppressor action studied on a simplified model of suppression activity registration

The addition of bone marrow cells to spleen cells and lymph node cells stimulates by mitogents, but not to fibroblast-like cells, leads to a significant reduction of DNA synthesis in mixed cultures in vitro. The suppression effects appears only in two days and the suppressor cell activity is the stronger, the intensive is the target cell proliferation. It is shown that intact bone marrow cells can suppress the lipopolysaccharide-activated bone marrow cell proliferation in vitro. A conclusion may be draw that cells of the lymphoid system serve as target cells for the bone marrow suppressor cells, and the role of these lymphoid system cells is to control immunogenesis processes by suppressing the target cell proliferation activity in the bone marrow.     

Formation of an IgM and an IgG immune response depending on the redistribution of T- and B-subpopulations under the action of serotonin]

The syngeneic transfer of spleen cells or spleen and lymph node cells from donors with an elevated serotonin level stimulated, in comparison with the control animals, immune response in the recipients subjected to sublethal irradiation, which was manifested by an increase in the number of plaque-forming and rosette-forming cells. After the combined transfer of spleen cells and bone marrow cells from similar animals a decrease in the number of plaque-forming and rosette-forming cells was observed, while after the transfer of spleen and thymus cells the intensity of immune response remained unchanged. Serotonin was supposed to induce the redistribution of T and B cells in the non-immunized animals, so that suppressor cells migrated from the spleen and the lymph nodes to the bone marrow.     

Specific activation of lymphocytes against acetylcholine receptor in the thymus in myasthenia gravis

In 13 patients with myasthenia gravis, spontaneous in vitro production of antibody to acetylcholine receptor (AChR) by thymic cells was observed in seven patients, by bone marrow cells in nine, by peripheral blood cells (PBL) in six, and by lymph node cells in nine. The rate of anti-AChR production in culture closely correlated with the serum anti-AChR level. Specific activity of the immunoglobulin (Ig) G spontaneously produced (anti-AChR/total IgG) was about 10-fold higher in the thymus than in bone marrow, peripheral blood, or lymph node cultures. Pokeweed mitogen (PWM) enhanced anti-AChR production only by PBL. With neither thymus nor lymph node cells did PWM stimulate anti-AChR production, although it greatly enhanced total IgG production. In bone marrow, it depressed both, and it appeared that the anti-AChR was derived from long-lived plasma cells that may be responsible for delaying the fall of serum anti-AChR levels after thymectomy. The results suggest that AChR-specific cells are selectively activated in the thymus, and this may help to explain the benefits of thymectomy in myasthenia gravis.     

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.     

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.     

Feasibility and limits of an orthotopic human colon cancer model in nude mice

We sought to develop an accurate colorectal cancer model in nude mice with stable local growth, tumor cell dissemination, and reproducible metastatic capacity. To this end, we orthotopically transplanted histologically intact human colorectal cancer tissue from 10 human patients into nude mice. After successful local tumor growth, tumor tissues were retransplanted as many as 9 times in serial passage. All specimens were transplanted using microsurgical techniques. Histologic, immunohistochemical, and polymerase chain reaction techniques were used to determine tumor growth rates and kinetics, development of regional lymph node and distant hepatic metastases, and the induction of minimal residual disease (MRD). Stable local tumor growth rates with variable growth kinetics were detected in 73.4% of all mice. The lymph node and hepatic metastasis rates were low, at 18.4% and 4.9%, respectively. MRD, as reflected by CK20 positivity of the bone marrow in animals with lymph node and hepatic metastases, was present in 22.2%. The orthotopic colorectal cancer model described here is feasible for the induction of reproducible local tumor growth but is limited by variable growth kinetics and the low rate of lymph node and hepatic metastases. Cytokeratin-positive cells indicative of MRD could be detected in the bone marrow of approximately 25% of the nude mice with metastases. The observed induction of MRD after orthotopic implantation of intact human colon cancer in animals with lymph node and hepatic metastases might be improved if established colon cancer cell lines were used.     

Studies on the maturation of immune responsiveness in the mouse. II. Role of the spleen.

Experiments were designed to investigate the role of the spleen in the development of the murine immune system. By using mice splenectomized within 24 hr of birth, as well as mice with a hereditary, congenital absence of the spleen, the primary immune response to sheep erythrocytes was examined. The immunocompetence of lymph node cells from spleenless or control mice was assessed in vitro, in organ and in cell suspension cultures, and in vivo, by transfer into lethally irradiated syngeneic recipients followed by antigenic stimulation. The immunologic capacities of thymus and bone marrow cells were similarly tested by injection separately or in combination into irradiated syngeneic mice. Lymph node cells from spleenless animals appeared fully competent both in vitro and in transfer experiments. Neither neonatal splenectomy nor congenital absence of the spleen significantly reduced the capacity of bone marrow or thymus cells to participate in the immune response to sheep erythrocytes.     

Adoptive Transfer of Immunity to Plasmodium berghei

SYNOPSIS. Immunity to P. berghei in rats was transferred adoptively with spleen cells but not with bone marrow cells, thymus cells, peripheral lymph node cells or thoracic duct lymphocytes from immune donors. The parasite multiplies at the same rate in control and protected rats but when about 10% of host red cells are infected the number of infected cells in protected rats decreases rapidly whereas control rats attain high parasitemias and die. Serum from immune donors delays the onset of parasitemia but does not affect its ultimate course or the fate of the recipient.     

Immune mechanisms in leukemia: protective capacity of the major lymphoid cell compartments.

The capacity of immune spleen, lymph node, peritoneal, bone marrow, and thymic cells to protect C58/wm mice from syngeneic transplanted line Ib leukemia was quantified. Cells harvested 14 to 15 days after primary immunization were used for adoptive protection tests. Regression curves were computer analyzed and log10, PD50 values compared. For immune spleen, lymph node, peritoneal, bone marrow, and thymic cells the PD50 values were 4.53, 5.92, 4.88, 5.51, and 5.59, respectively. When immune spleen cells were treated with anti-Thy 1.2 serum the PD50 value was increased from 4.73 to 6.09, i.e., protection was reduced greater than or equal to 95%. Similar treatment of immune thymic cells reduced protection below measureable values. Anti-B cell sera (anti-IgM and anti-Ly 4.2) did not reduce the protective effect of immune spleen or marrow cells. These results indicate that a major protective cell population in each of these compartments was theta-positive. Experiments were carried out to characterize the cortisone (CS) and x-ray sensitivity of immune spleen, thymic, and marrow cells .When donor mice were treated with 12.5 mg of cortisone acetate/day for 2 days before lymphoid cells were harvested, the orotective effects of immune spleen cells, but not immune thymic or marrow cells, was reduced. When immune spleen cells were x-irrated in vitro, their protective effect was reduced by 350 R and abolished by 1000 R. When mice received whole boyd x-irradiation 24 hr before immune spleen cells were transferred their protective effect was reduced by 1000 R but only slightly lowered by 350 R. The possible significance of the multicompartmental nature of immunity to leukemia was discussed.     

Effect of tumor immunity on the distribution of labeled lymphoid cells in tumor-challenged mice

The distribution of ⁵¹Cr-labeled lymphoid cells from normal mice and mice immunized against a tumor were compared after intravenous inoculation of the labeled cells into normal syngeneic recipients. Spleen cell preparations from immune donors contained increased percentages of spleen and bone marrow-seeking cells, thus suggesting expansion of these cell populations when immunity to a tumor exists. Homing of labeled normal cells in tumor cell-injected normal animals was somewhat different from that seen in tumor cell-inoculated mice that were immunized against the tumor. In the latter case, accumulations of lymph node and spleen cells in recipient lymph nodes and bone marrow were consistently lower. In contrast, lymphoid cells from animals immunized against the tumor were found to accumulate in virtually the same percentages in lymphoid organs of normal and immune recipients. The behavior of lymphoid cell populations from thymus or bone marrow that consist mainly of precursor cells was unaffected by presence of malignancy and/or tumor immunity.     

Characteristics of the reactions to N-alloantigens of lymphoid cells from hydrocortisone-stimulated and adrenalectomized mice]

The capacity of the spleen, bone marrow and thymus cells from CBA mice (intact, adrenalectomized, and those treated with single or repeated hydrocortisone injections) to induce the lymph node type of "graft-versus-host" reaction (GVHR) in (CBA X C57BL) F1 hybrid recipients was evaluated. Two days after 2.5 mg hydrocortisone injection the capacity of the spleen and bone marrow cells to induce GVHR increased while that of the thymus cells remained unchanged. Seven and particularly 15 days after hydrocortisone injection the spleen cells became less active. Two days following repeated daily hormone injections in a dose of 0.25 mg within 18 days the thymocyte activity in GVHR increased, while that of the spleen and bone marrow cells did not change.     

Autoaggressive immunocompetent cells in the bodies of mice at remote periods following irradiation]

Lethally irradiated DBA/l mice or (C57Bl X DBA/l1 F1 hybrid mice were injected with therapeutically effective doses of isologous bone marrow cells; simultaneously syngeneic lymph node cells from either intact (control) animals or mice survived after sublethal irradiation were transplanted. In control the viability of the recipients was not affected by the presence of lymphoid cells in the mixed transplant. In contrast, the beneficial action of the bone marrow cells was abolished (killing-effect) by the lymphoid cells from mice sacrificed 6 to 12 months after the irradiation (600--700 r). The manifestation of the killing-effect depended on the number of the transplanted lymphoid cells and on the dose of the bone marrow cells in the transplant. The killing-effect was not revealed when the lymphoid cells were obtained from the donors on the 30th day after irradiation. The results suggest the autosensitization of the organism at the late postirradiation periods.