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PubMed1987

Mechanism of recovery from acute virus infection. IV. Questionable role of mononuclear phagocytes in the clearance of lymphocytic choriomeningitis virus from spleens of mice.

After intravenous infection of mice with 10(3) infectious units (IU) the WE strain lymphocytic choriomeningitis (LCM) virus multiplied in the spleens (as in all other major organs), reaching more than 10(8) IU/g of tissue on days 4 to 5. Subsequently, the virus was quickly eliminated, being below detectability usually by day 10. During the time of virus clearance, the mononuclear phagocytes (MNP) of the spleen were activated as revealed by suppression of growth of Listeria monocytogenes and increase of cell-associated hydrolytic enzymes. In athymic nude mice, in whom the MNP system is assumed to be permanently activated, the virus replicated slightly but reproducibly less than in their euthymic counterparts. However, when the MNP were activated by Corynebacterium parvum, virus in spleens attained higher concentrations than in mice not so treated, and the rate of elimination was not altered. In mice whose MNP had been damaged by injection of dextran sulfate 500, the spleen virus titers were also increased, but the subsequent immune elimination was slightly delayed. Activation of spleen MNP was not evident at the time virus was rapidly cleared as a result of transfusion of LCM-immune T lymphocytes. Adoptive immunization was as successful in mice that had been pretreated with gamma-rays or cyclophosphamide, suggesting that replicating cells or their descendants, in particular monocytes, did not participate measurably in the process of elimination. Pretreatments of recipients with dextran sulfate 500 reduced the efficacy of transfused LCM-immune T lymphocytes, but this compound probably directly affected the cells. We interpret these findings to mean that the LCM virus in the mouse's spleen is controlled by a mechanism in which MNP do not play an essential role.

Animals↗
PubMed1987

Distribution of substance P receptors on murine spleen and Peyer's patch T and B cells.

Previous studies have demonstrated that the sensory neuropeptide substance P (SP) can modulate immune responses in vitro. Work from this laboratory has shown that SP enhances immunoglobulin synthesis by murine splenic and Peyer's patch lymphocytes stimulated with concanavalin A. One mechanism underlying these effects is the binding of SP to specific receptors on lymphocytes. We examined the distribution of SP receptors on murine T and B lymphocytes and their subsets by one and two color fluorescence-activated cell sorter analysis. The specificity and nature of binding was examined using radiolabeled SP, and competitive inhibition experiments were performed with cold SP. In cytofluorimetry experiments, both T and B lymphocytes from Peyer's patches and spleen were bound to SP, with those from Peyer's patches having a higher proportion than lymphocytes from the spleen. The majority of T cells from both organs bound SP with binding being evenly distributed between Lyt-1+ and Lyt-2+ cells. Similarly, the majority of B lymphocytes from spleen and Peyer's patches showed SP binding. There were no significant isotype-specific differences within any organ. Studies using 125I-labeled SP showed specific binding to all lymphocyte subpopulations examined. SP receptors were fewer in number on cells isolated from spleen than on cells from Peyer's patches although the dissociation constants were similar for all populations examined. These studies demonstrated that SP receptors are present both on murine T and B lymphocytes from Peyer's patches and spleen. There is no evidence for differential SP receptor expression on distinct lymphocyte subsets in spleen or Peyer's patches.

Animals↗
PubMed1987

[Subcutaneous injection of spleen cells from mice bearing large methylcholanthrene-induced sarcoma enhances subcutaneous tumors and artificial pulmonary metastases].

To examine the effect of spleen cell on host antitumor immunity, spleen cells from mice bearing large Methylcholanthrene-induced sarcoma (MCA-F) (F4w spc) were injected subcutaneously into mice which had been inoculated subcutaneously with MCA-F cells or intravenously with the subline from MCA-F cells which had high potential of metastasis (FLn2). F4w spc enhanced significantly the growth of subcutaneous MCA-F tumor in a dose-dependent fashion (p less than 0.05) and increased the number of metastatic lesions induced by intravenous FLn2, but not spleen cells from normal mice or spleen cells from mice bearing MCA-D tumor which is antigenically different from MCA-F. These results suggest that spleen cells of mice bearing a large tumor have a component suppressing specifically antitumor immunity. In this study, effects of spleen cells were assessed by the subcutaneous injection into tumor bearing mice instead of Winn's assay, and this method was thought to be useful for analysis of effector cells in tumor immunity.

Animals↗
PubMed1988

Hemorrhagic autoimmune encephalomyelitis induced by adoptive transfer of activated semiallogeneic spleen cells into irradiated rats.

Using lethal irradiation of recipients, adoptive transfer of experimental allergic encephalomyelitis (EAE) into Lewis (LEW) rats using (LEW x PVG/c)F1 (LPVGF1) spleen cells was successfully achieved. Recipient rats usually developed clinical signs of EAE 5 or 6 days after transfer. The EAE was characterized by the presence of a number of petechiae over the spinal cord. Immunohistochemical examination using OX27, a monoclonal antibody specific for RT1.Ac, revealed the localization of transferred F1 (RT1(1/c] cells in the LEW recipients (RT1(1]. Most of the inflammatory cells in the spinal cord lesions were stained positively for OX27, indicating that they were transferred cells. In mild EAE, more W3/25+ cells were found than OX8+ cells. OX8+ cells were predominant in severe EAE, however. Examination of the spleens of rats that developed EAE by OX27 staining revealed that transferred F1 cells gradually increased in number and reached a maximal level on days 5 and 6. In the spleens of rats that received irradiation and transfer but did not develop EAE, few transferred F1 cells were observed. In addition, bromodeoxyuridine (BrdU)-anti-BrdU immunohistochemistry was employed to demonstrate that cell proliferation really takes place in the spleen. It was revealed that the spleens of the recipients of lethal irradiation and F1 cells contained many BrdU+ cells. Because rats given lethal irradiation alone had extremely few BrdU-positive cells in their spleens, labeled cells in the recipients of radiation and transfer originated from transferred F1 cells. Collectively, these findings strongly suggest that transferred cells previously activated in vitro undergo further proliferation in the lymphoid organs of recipients to bring about the development of EAE.

Animals↗
PubMed1988

[B- and T-lymphocyte compartments in the spleen in idiopathic thrombocytopenic purpura].

The exstirpated spleens of 62 patients in each case with idiopathic thrombocytopenic purpura (ITP) and traumatic rupture of the spleen were comparatively examined macroscopically, histologically and morphometrically. The mean follicle diameters of the spleen were significantly greater in ITP patients than in those of controls. With 500 microns identified as an upper limit of normal follicle diameter, ITP patients could be divided into two groups of equal size below and above this limiting value. The thrombocyte values determined at the time of splenectomy and 6 months before it were significantly lower in ITP patients with enlargement of spleen follicles than in those ITP patients with spleen follicle being in the normal range. Thus, the morphometrical determination of the spleen follicle size can provide a semi-quantitative reference to the extent of synthesis of autothrombocytic antibodies. In T-lymphocyte compartments there was no difference between ITP and controls.

Adolescent↗
PubMed1989

Prolongation of heart graft survival and spleen suppressor cell activity after donor specific blood transfusions in rats differing across the MHC.

The aim of the study was the prolongation of heart allograft survival in rats after DST (donor specific blood transfusion), the characterization of T and B lymphocyte phenotypes in peripheral blood, spleen and lymph nodes and the evaluation of specific and nonspecific suppressor cell activity of spleen and blood lymphocytes of DST rats. Pretreatment of Wistar recipients with one, two and three doses of DST-s prolonged the heterotopic August graft survival to 11.0, 12.3 and 11.4 days, respectively (rats differed across the MHC). Spleen lymphocytes of transfused rats showed significant nonspecific suppressive activity in culture with syngeneic spleen lymphocytes of nontransfused rats stimulated with PHA, but not in culture with blood lymphocytes. Blood lymphocytes of transfused rats did not show any nonspecific suppressive activity. Spleen and blood lymphocytes of transfused rats did not demonstrate any specific suppressive activity in allogeneic MLC. The ratio of W3/25+/OX8+ (Th+/Tsup/cyt+) cells in peripheral blood was found increased in DST rats due to the decrease in the percentage of OX8+ cells whereas the opposite effect was observed with spleen cells (increase in the percentage of OX8+ cells after one DST). The number of OX6+ (Ia positive) cells and B cells in all transfused rats was found unchanged comparing with untreated animals.

Animals↗
PubMed1985

The target minor H antigen for F1 cytotoxic T lymphocytes induced by Igh-congenic parental spleen cells is coded for by gene linked to H-2.

Graft-vs-host reaction (GvHR) induced in (B10.BR X CWB)F1 (BWF1; H-2k/b, Ighb/b) by i.v. injection with CWB (H-2b, Ighb) spleen cells resulted in complete suppression of cytotoxic T lymphocyte (CTL) responsiveness of the F1 host spleen cells (GvHR-associated immunosuppression). In contrast, GvHR induced in BWF1 mice with CSW (H-2b, Ighj; Igh-congenic to CWB) spleen cells did not affect CTL responsiveness of the F1 host spleen cells at all. The BWF1 hosts undergoing the CSW-induced GvHR generated anti-CSW CTL in their spleens, and the subsequent culture of such BWF1 spleen cells with CSW stimulator cells, augmented the CTL activity. The BWF1 anti-CSW CTL lysed both Con A- and LPS-induced splenic blasts from mouse strains carrying the Ighj allele in the context of self H-2Kb. However, determination of the Igh haplotype in the serum IgG and of the susceptibility of the splenic lymphocytes to the BWF1 anti-CSW CTL on backcross mice, which carry either Ighb/j or Ighb/b in the context of H-2b/b or H-2b/k, showed clearly that Ighj and the gene coding for the target antigen for the BWF1 anti-CSW CTL segregated at ratios close to 1:1. The study in which linkage between the gene(s) coding for the target antigen for the BWF1 anti-CSW CTL and H-2 was examined on CWB X (C3H X CWB)F1 backcross mice and (B10.BR X CSW)F1 X B10 mice demonstrated that the gene, most likely a single gene, coding for the target antigen for the BWF1 anti-CSW CTL is located at 8.5 +/- 4.3 cross-over units to the right or left of the H-2 complex. We designated the minor H antigen to be recognized by the BWF1 anti-CSW CTL as H-X+, and we discuss the distinction between the H-X+ locus and the other minor H loci on chromosome 17.

Animals↗
PubMed1989

On the late seeding of CFU-S to the spleen: 8- vs 12-day CFU-S.

Marrow from 5-fluorouracil- or cyclophosphamide-treated mice, injected into lethally irradiated recipients, gives an increasing number of spleen colonies between days 7 and 14. It has been suggested that the later-forming colonies result from the more primitive spleen colony-forming units (CFU-S), which first seed into the marrow, only later to be recirculated and form colonies in the spleen. Strontium 89 (89Sr), a bone-seeking radionuclide, was injected into recipient mice to block such putative recirculation. A dose of 89Sr, which killed at least 99.8% of CFU-S in, or entering, the bone cavities, was incapable of preventing the increase in spleen colony numbers. Similarly, the splenic environment, modified by the presence of spleen colonies and able to provide a better bed for trapping CFU-S from the peripheral circulation, yielded the same number of further CFU-S, whether or not the animal had received 89Sr. Thus, it was concluded that the 12-day CFU-S does not seed initially into the marrow spaces. Direct observation of the quality of CFU-S initially seeding into the bone marrow and spleen showed, by retransplantation into secondary irradiated mice, that a similar spectrum of CFU-S types had seeded both organs.

Animals↗
PubMed1989

The evaluation of spleen function in man.

The usual methods for the functional evaluation of the spleen in man are based on the measurement of a) spleen volume, b) spleen uptake of particles from the circulating blood, and c) morphological abnormalities of circulating erythrocytes. Analysis of clearance curves of damaged autologous erythrocytes, measurement of spleen size or volume by scintillation scanning and counting of erythrocytes with pits by interference contrast microscopy at present are the most widely used techniques. The most frequent causes of acquired functional abnormalities of the spleen are the sickle cell diseases, inflammatory intestinal diseases, immune complex diseases, chronic myelogenous leukemia, irradiation, hemophilia, and the hyposplenism of newborn infants and of the elderly. Usually there is a parallelism enlarged or normal-sized spleen with decreased function, has been observed in sickle cell syndromes and occasionally in chronic myelogenous leukemia and hemophilia.

Adolescent↗
PubMed1989

The retrorenal spleen. Implications for percutaneous left renal invasive procedures.

An uncommon but potentially disastrous situation for invasive percutaneous renal procedures is the presence of the spleen behind the upper left kidney. We have termed this anatomic variant "retrorenal spleen." In a computed tomographic (CT) review of 73 patients aged 16 to 86, we found a frequency of retrorenal spleen of 21.1% in the supine and 15.4% in the prone patient. In most individuals with this variant, the spleen was behind the lateral fifth and the superior fourth of the left kidney. The majority (80.0%) of these patients were age 50 or over. However, in only 7.6% would the posterior splenic position pose a risk to posterolateral percutaneous approaches of less than 30 degrees into the upper left collecting system. No patient had retrorenal spleen at the mid-hilar level in either the supine or prone position. Posterolateral approaches up to 40 degrees into the renal hilus are 100% safe from intervening spleen.

Adolescent↗
PubMed1989

Comparison of sister chromatid exchanges in spleen and thymus lymphocytes from AKR, C57BL/6N x DBA/2J F1, and CBA mice following in vivo exposure to N-methyl-N-nitrosourea.

The induction of sister chromatid exchange (SCE) by N-methyl-N-nitrosourea (MNU) was studied in spleen and thymus lymphocytes from AKR mice, which are highly susceptible to MNU-produced thymomas, CBA mice, which are much less sensitive to induction of thymomas by MNU, and C57BL/6N x DBA/2J F1 mice. MNU produced dose-related increases in SCE in concanavalin A (Con A)- and lipopolysaccharide-stimulated spleen lymphocytes and Con A-stimulated thymus lymphocytes from each mouse strain at 1 and 24 h posttreatment. MNU-induced SCE were generally higher in Con A-stimulated spleen lymphocytes compared to lipopolysaccharide-stimulated spleen lymphocytes and Con A-stimulated thymus lymphocytes from each mouse strain. On the whole, MNU-produced SCE were lower in AKR and CBA spleens than in C57BL/6N x DBA/2J F1 spleens. In addition, MNU-induced SCE levels in thymus lymphocytes from all three strains of mice were, for the most part, similar. These results indicate that if differences in MNU-induced genotoxicity in AKR, CBA, and C57BL/6N x DBA/2J F1 thymus lymphocytes exist, these differences cannot be ascertained by use of the in vivo/in vitro SCE assay.

Animals↗
PubMed1989

[Examination of the injured spleen using computer tomography].

In blunt abdominal injury the most frequently injured organ is the spleen. A rapid and precise diagnosis of an injured spleen is therefore of great importance for early and correct therapeutic procedure. The authors present a group of 56 patients, who have been examined in the 1981-1987 years after blunt injuries of the belly by computer tomography. In 12 cases there was the diagnosis of subcapsular haematoma of the spleen, intraparenchymatous rupture was present in eight patients. In the remaining 36 cases the trauma of abdominal organs was not confirmed. All findings were verified by surgery or a control computer tomography and clinical examination of the patients. The authors demonstrate typical traumatic conditions. Computer tomography is a very useful method which enables a rapid, precise and non-invasive diagnosis of different degree of the spleen injury, its possible complications and differentiates these conditions from uninjured spleen. The authors present a brief survey of pictures of injured spleen in other methods of examination. In comparison with those methods, computer tomography is the most effective one, which provides a complex information of other organs of abdominal cavity. It also enables a considerate examination of patients severely injured and in non-cooperating ones.

Adolescent↗
PubMed1989

Lymphocyte migration in the spleen: the effect of macrophage elimination.

To study the influence of macrophages on the migration and distribution of lymphocytes in the spleen, macrophages were eliminated from the spleen of mice by injection of liposomes in which DMDP was encapsulated. This leads to an elimination of macrophages in both the red pulp and marginal zone of the spleen within 1-2 days. In these animals the distribution of lymphocytes was determined by transfer of either syngeneic fluoresceinated or Ly 5 congeneic cells. It was found that after elimination of the macrophages the number of lymphocytes immigrating into the spleen had decreased, although a comparable mode of compartimentalization was found with an initial localization in the marginal zone and a subsequent distribution into the white pulp. After this elimination spleen macrophage subsets return with different kinetics, and in this way the influence of the red pulp macrophages, the marginal zone macrophages and the marginal metallophilic macrophages on lymphocyte immigration and redistribution could be investigated. A quantitative decrease of immigration was still found when red pulp and marginal metallophilic macrophages had repopulated their compartments, but was only fully restored when the last population to repopulate the spleen after treatment with DMDP-liposomes, the marginal zone macrophages, had returned. Experiments with isolated T and B cells showed that the elimination of macrophages had a profound effect on the localization of B cells in the white pulp, whereas it hardly affected T cells.

Animals↗
PubMed1989

Functional heterogeneity of macrophage precursor cells from spleen of Leishmania donovani-infected and untreated mice.

We recently described the bone marrow-derived macrophage precursor, which is able to spontaneously and extracellularly kill protozoa of the genus Leishmania. These nonadherent, nonphagocytic macrophage precursor cells are present in the spleen of healthy mice only in a small quantity. However, high numbers of proliferating macrophage precursors are isolated from the spleen of Leishmania donovani-infected mice. Macrophage precursors from spleens of diseased animals are able to kill spontaneously the promastigote as well as the amastigote form of L. donovani. The mechanism of the spontaneous leishmanicidal activity of macrophage precursor cells derived from spleens of L. donovani-infected mice was investigated. This effector function could be defined in part as an antibody-dependent cellular cytotoxicity. In addition we assessed the role of CSF-1-containing L cell-conditioned supernatant at the leishmanicidal activity of these immature cells of the macrophage lineage. For that purpose, nonadherent spleen cells from healthy mice were cocultivated with this CSF-1-containing medium for 4 days. These in vitro proliferated macrophage precursor cells from untreated mice showed an increased leishmanicidal activity. Thereby we established a further activation mechanism for proliferating splenic macrophage precursor cells responsible for the observed killing of L. donovani pro- and amastigotes. The spontaneous cytotoxicity of macrophage precursors from spleens of L. donovani-diseased animals is thus defined as a cooperative effect of antibody-dependent cellular cytotoxicity and Macrophage-CSF activation.

Animals↗
PubMed1989

Spleen cellularity shifts from the inhalation of 0.25-0.35 PPM nitrogen dioxide.

The effects of ambient level (0.25-0.35 ppm)NO2 on percent spleen cell counts, relative percentages of spleen lymphocyte subpopulations, spleen lymphoid nodule size, and differential peripheral blood cell counts were investigated in 170 young adult male mice following various NO2 exposure periods. The total spleen cell counts, surface IgM-positive lymphocytes and spleen mean lymphoid nodule area were all significantly decreased in the groups exposed to NO2 following extended time periods. The relative percentages of peripheral blood lymphocytes were also significantly decreased in the groups exposed to NO2 for 8 weeks. The mechanism for these observed spleen changes following ambient level NO2 exposure remains unclear, but the results warrant further investigation and concern, especially since such changes may reflect altered immune responsiveness.

Animals↗
PubMed1988

Suppressor T cells and self-tolerance. Active suppression required for normal regulation of anti-erythrocyte autoantibody responses in spleen cells from nonautoimmune mice.

Spleen cells from young, nonautoimmune strains of mice cultured with syngeneic E do not develop a significant anti-mouse E response in vitro, consistent with a state of self-tolerance to this Ag. In order to study the role of active suppression in regulating mouse RBC-(MRBC) specific cells in nonautoimmune cell populations, the effect of depleting T cell subsets on the generation of anti-MRBC autoantibodies by nonautoimmune spleen cells was determined. Spleen cells from young BALB/c and C57BL/6 mice were found to generate significant numbers of IgM and IgG anti-MRBC autoantibody-forming cells in culture with MRBC after depletion of Ly-2+ cells by anti-Ly-2 and C treatment. The response which develops is Ag dependent, Ag specific, and dependent upon L3T4+ Th. The magnitude and isotype of this response is similar to the anti-MRBC response generated by spleen cells from 12-mo-old, autoimmune NZB mice and young NZB mice also treated to remove Ly-2+ cells. Addition of isolated Ly-2+ T cells, but not L3T4+ or Ly-2- T cells, to spleen cells depleted of Ly-2+ cells restores apparently normal regulation of the anti-MRBC response in vitro. These data demonstrate that control of a specific autoantibody response to MRBC by nonautoimmune spleen cell populations requires active regulation by an Ly-2+ T cell subset.

Animals↗
PubMed1977

[Antibody formation and B-cell migration from bone marrow to spleen in mice under conditions of stimulation and suppression of erythropoiesis].

The effect of erythropoietic stimulation and suppression on the production of antibody-forming cells (AFC) in the spleen and on the B-cell migration from the bone marrow to the spleen was investigated in the CBA mice. Erythropoiesis stimulation proved to sharply increase the AFC count in the spleen and the B-cell migration from the bone marrow to the spleen 1 and 4 days after the bleeding. Erythropoiesis suppression resulted in a slight increase of the AFC count in the spleen 4 and 7 days after the transfusion of syngeneic red blood cells. However, the erythropoietic suppression inhibited the B-cell migration from the bone marrow to the spleen. Possible mechanisms of the effect of the erythropoietic stimulation and suppression on the antibody production are discussed.

Animals↗
PubMed1987

Biochemical and immunological characterization of rat spleen prostaglandin D synthetase.

Rat spleen prostaglandin D synthetase (Christ-Hazelhof, E., and Nugteren, D. H. (1979) Biochim. Biophys. Acta 572, 43-51) is very similar to rat brain prostaglandin D synthetase (Urade, Y., Fujimoto, N., and Hayaishi O. (1985) J. Biol. Chem. 260, 12410-12415) as judged by their pI (4.7-5.2), Mr (26,000-27,000), and self-inactivation during the isomerase reaction from prostaglandin H2 to prostaglandin D2. However, the amino acid compositions of these two enzymes were quite different. Furthermore, the spleen enzyme was associated with the glutathione S-transferase activity, differing from the brain enzyme. The synthetase and transferase activities of the spleen enzyme showed almost identical pH and glutathione dependencies, the optimum pH = 8.0 and Km for glutathione = 300 microM. The Km values for prostaglandin H2 and 1-chloro-2,4-dinitrobenzene (a substrate for the transferase) were about 200 microM and 5 mM, respectively. The synthetase activity was dose-dependently inhibited by 1-chloro-2,4-dinitrobenzene (IC50: approximately 5 mM) and more strongly by nonsubstrate ligands, such as bilirubin and indocyanine green (IC50: 150 and 2 microM, respectively). Both the synthetase and transferase activities of the purified enzyme dose-dependently decreased and showed identical immunotitration curves by incubation with antibody against this enzyme, but remained unchanged when treated with antibody against the brain enzyme. The antibody specific for the spleen enzyme absorbed almost all of the synthetase activity and about 10% of the transferase activity in the spleen, but not the transferase activity in the liver, heart, and testis. These results show that the two types of prostaglandin D synthetase are similar but different enzymes and that the spleen enzyme is a unique glutathione S-transferase differing from other isozymes and their subunits reported previously.

Amino Acids↗