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PubMed1987

Defective T helper activity in the spleen of BALB/c mice immune to a syngeneic fibrosarcoma.

BALB/c mice were immunized with the syngeneic 3-methylcholanthrene-induced fibrosarcoma CA-2 by the growth and excision method. When lymphoid cells from different organs of these tumor-free mice were tested in a direct 51Cr-release assay, peritoneal exudate cells but not spleen cells displayed specific cytotoxicity against the syngeneic tumor target. A cytotoxic response could be obtained by tumor-immune spleen cells when cultured in a mixed lymphocyte tumor cell culture (MLTC) at high but not low density although at the same effector/stimulator ratio. Lack of cytotoxic activity in low density MLTC was not due to an impairment of cytotoxic precursors since cytotoxicity was rescued by adding exogenous interleukin-2 in experimental conditions in which no lymphokine-activated killer cells could develop relevant anti-CA-2 lysis. When low density MLTC were supplemented with either 800 R-irradiated cells or nonirradiated, negatively selected Lyt 1+ cells from the same immune mice, induction of a cytotoxic response against CA-2 occurred and interleukin-2 production became detectable. Additional studies indicated that spleen cells of CA-2-immune mice were also impaired in their ability to provide help to syngeneic thymocytes for the generation of cytotoxic T lymphocytes against C57BL/6J alloantigens. Dilution effect of helper cells due to immunization procedures was excluded since spleen cells of mice immunized against another BALB/c tumor, the YC8 lymphoma, or against DBA/2 minor histocompatibility antigens provided good help to thymocytes against the same alloantigens. These results indicate that tumor-immune animals may also have selective T helper defects in an important lymphoid organ like spleen.

Animals↗
PubMed1984

Elimination of phagocytic cells in the spleen after intravenous injection of liposome-encapsulated dichloromethylene diphosphonate. An enzyme-histochemical study.

Dichloromethylene diphosphonate can be used for temporary elimination of macrophages in the spleen when administered after entrapment in liposomes. No comparable effect on the macrophages of the spleen was observed with free dichloromethylene diphosphonate or in the case of empty liposomes. Marginal metallophils on the boundary between white pulp and marginal zone as well as macrophages in the marginal zone and red pulp disappeared from the spleen within one day and remained largely absent for about a week. After this time cells reappeared slowly, and at approximately four weeks after injection their presence in the spleen did not differ from that in control animals. Marginal metallophils and macrophages in the spleen were demonstrated by use of enzyme-histochemical methods and by their capacity to ingest carbon particles.

Acid Phosphatase↗
PubMed1975

Effect of calcium on the relationship between frequency of stimulation and release of noradrenaline from the perfused spleen of the cat.

The sympathetic nerves of the cat spleen were stimulated electrically (20 v, 1 msec, 7 sec) with increasing frequencies (1-30 Hz) during perfusion of the spleen with normal or low-calcium Krebs solution. Noradrenaline (NA) output per stimulus was measured. In spleens perfused with normal Krebs solution, the NA output per stimulus at 5Hz was barely detectable, while the output at 30 Hz was about 5-fold greater than at 5 Hz. Reduction of the calcium concentration in the Krebs solution to 0.2-0.5 mM, while reducing outputs at both frequencies, resulted in an output at 30 Hz that was nearly 8 to 10 times that at 5 Hz. In spleens pretreated with phenoxybenzamine (PBZ) the NA output was increased at all frequencies, and the maximal output occurred at 5 Hz, whereas the output at 30 Hz was only one-third of the maximal output. Reduction of the calcium concentration of the perfusion solution to 0.5 mM, while reducing outputs from PBZ-treated spleens, increased the output at 30 Hz by about 5-fold over the output at 5 Hz. The muscarinic inhibition of stimulation-evoked release of NA by acetylcholine was much more pronounced at low than at high frequency of stimulation. The increase in the release of NA per stimulus with increase in the frequency of sympathetic nerve stimulation is explained on the assumption that the specific entry of calcium ions required for transmitter release is also frequency-dependent.

Acetylcholine↗
PubMed1978

Wandering spleen in three children.

Three children with wandering spleen are presented. Liver-spleen technetium99m sulphur colloid scintigraphy is a helpful diagnostic tool that will demonstrate the abnormally located spleen or absent splenic activity when the blood supply is interrupted by a twisted pedicle. The diagnosis can also be made by angiography, but this relatively elaborate procedure is usually not necessary. Absence of the normal ligamentous attachments of the spleen associated with a long splenic pedicle may well be the cause of the wandering spleen and its torsion.

Adolescent↗
PubMed1986

Retroviral endogenous transcripts related to the envelope gene of Friend spleen focus-forming virus in normal mouse tissues.

Retroviral endogenous sequences related to the envelope (env) gene of Friend spleen focus forming virus (SFFV) and of mink cell focus forming viruses (MCF) are present in the genome of various mouse strains. We have examined the transcription of these SFFV/MCF-related sequences in normal tissues of two mouse strains, ICFW and DBA/2. Cytoplasmic Poly A+ RNAs of normal mouse tissues were analyzed by dot-blot and Northern blot hybridizations with a subcloned env SFFV DNA fragment (0.4 kbp BamH I-Sma I). In both mice, the level of SFFV/MCF env related transcripts was very low in bone marrows and spleens whereas it was high in kidneys. Intermediate levels of transcripts were observed in other tissues (thymus, liver and brain). In both mouse strains, the size of SFFV/MCF env related transcripts varied from one tissue to another. Some transcripts in DBA/2 mice were reminiscent of full-size viral message indicating an occasional expression of xenotropic/MCF endogenous virus in this low-leukemic strain. Sizes of the other SFFV/MCF related env transcripts were unusual, but were similar in both strains for each tissue studied. This last result suggests a tissue-specific transcription of endogenous sequences related to the SFFV/MCF env gene. A 1.8 kb SFFV/MCF env RNA was the major transcript in the tissues which expressed a high level of these env transcripts. Treatment of mice with phenylhydrazine which greatly stimulates erythroid differentiation in spleens increased the level of SFFV/MCF related env RNAs only in the spleens, suggesting a possible correlation between the SFFV/MCF env transcription and the stimulation of the erythroid spleen cells.

Animals↗
PubMed1981

Generation of lipopolysaccharide-induced interferon in spleen cell cultures. I. Genetic analysis and cellular requirements.

Incubation of murine spleen-cell cultures with lipopolysaccharide (LPS) induces interferon (IF) production. Maximal IF levels are obtained after incubation with 100 microgram/ml for 10 h. Two inbred mouse strains differing in their ability to generate LPS-induced IF in spleen-cell cultures were used: C3H/eB, which generates high levels of IF (about 60 units/ml), and C3H/HeJ, which fails to generate detectable quantities of IF. In a genetic analysis these strains were hybridized and IF production was determined in spleen-cell cultures from F1 and F2 generations, and from backcrosses of F1 hybrids to parent strains. The results indicate that, in parent strains, a single dominant autosomal gene is responsible for differences in IF production in spleen cultures. LPS-induced IF in spleen-cell cultures resists pH 2 for as long as 48 h, but is labile to heating at 56 degrees C for 30 min. Both macrophages and lymphocytes must be present in cultures for generation of LPS-induced IF. By using mixed cultures of macrophages and lymphocytes from C3H/eB and C3H/HeJ mice, it was shown that macrophages have to interact directly with LPS to enable IF production in the cultures.

Animals↗
PubMed1995

Wandering accessory spleen.

A patient with an excessively mobile accessory spleen detected on ultrasound examination is reported in whom a normally located spleen was also found. Sonographic and colour Doppler imaging criteria were used for making the specific diagnosis. The large accessory spleen has been demonstrated at different sites within the abdomen on subsequent follow-up sonographic examinations. The splanchnic flow pattern obtained from the long vascular pedicle of the accessory spleen indicated normal perfusion. Since the perfusion of the wandering accessory spleen was not compromised by torsion, and the patient refused surgical intervention, a conservative approach was considered to be appropriate.

Congenital Abnormalities↗
PubMed1985

Splenic architecture reflected in the connective tissue structure of the human spleen.

An analysis of the connective-tissue structure of the human spleen can give us information about the basic architecture of the organ. The most important part of the spleen is the lienic center around which the subcapsular zone forms an envelope, like a mantle. This zone has but little depth and develops superficially. The tangential radial beam net ('Tangentialbalkennetz') is formed partly by the radial trabeculae of the capsule and partly by the outer branches of the arbor trabecularis. This arbor divides into 5-6 branching orders. The branches of orders 1 to 3 surround the parenchyma of the spleen center's inner layer. The lienic lobuli which are found between the branches are relatively large and are connected very extensively with their parenchyma. The branches of orders 4, 5, and 6 enclose the lienic lobuli of the outer layer of the spleen center. The splenic lobuli are defined by the vascular course. Mostly they are provided with one or two arterial influxes and, as a rule, with only one venous drain. Their mutual delimitation is more of a functional than of a morphological nature. This led von Herrath to coin the term 'functional spleen lobuli'. The lienic envelope lies between the inside of the capsule and the outermost branchings of the arbor trabecularis. This arbor is subdivided, by the radial trabeculae, which never have any vessels, into elongated lobuli and serves first and foremost to regulate pressure. The lattice fibers are of high tensile strength and are extensions of the collagenous fibers seen at the microscopic level.

Connective Tissue↗
PubMed1992

Age-related differences in the effect of in vivo administration of indomethacin on hemopoietic cell lineages of the spleen and bone marrow of mice.

During 21 days of indomethacin treatment, erythroid cells in the spleens of both young adult and older mice, and in the bone marrow of young adult mice, were increased significantly early in treatment, relative to age-matched control organs, and remained high throughout treatment. During drug exposure, the numbers of myeloid cells in young adult bone marrow, but not spleen, were reduced, but in older mice these cells were elevated in both organs. Lymphoid cells in the young adult and older mouse spleens decreased and increased, respectively, during treatment, but were unchanged and decreased, respectively, in the bone marrow of young adult and older mice. Monocyte-macrophage cells in the spleen were elevated but unchanged in the bone marrow of both age groups. During 14 days of indomethacin treatment of young adult mice, the proportions of precursor cells in DNA synthesis of only the splenic erythroid lineage were increased. Thus, the major hemopoietic lineages in both the bone marrow and spleen are affected by exposure to indomethacin in a time-dependent and age-dependent manner. For all lineages studied, those of the bone marrow were least disturbed and/or were first to recover, even during continued drug exposure.

Age Factors↗
PubMed1976

Detection of cytotoxic lymphoid spleen cells from STU-mice with Moloney sarcoma by a 3H-proline microcytotoxicity assay.

A microcytoxicity assay with 3H-proline prelabeled target cells was used for the detection of sensitized lymphoid spleen cells from STU inbred mice inoculated with Moloney sarcoma virus (MSV-M) or ascitic MSV-M tumor cells. The target cell line was derived from ascitic MSV-M tumor cells. With regard to the specificity of the assay nonimmune slpeen cells displayed no or only a weak cytotoxicity against these cells, and this was also the case when 3H-proline-labeled secondary cultures of syngeneic mouse embryo cells were exposed to both sensitized and nonimmune spleen cells. The time-course pattern of the development of cytotoxic lymphoid spleen cells in STU mice inoculated intramuscularly either with MSV-M or ascitic MSV-M tumor cells was studied. At the stages of tumor development, peak tumor size, and tumor regression the lymphoid spleen cell preparations were found to have relatively strong cytotoxic activity independent of whether the tumor was induced by MSV-M inoculation or tumor cell transplantation. However, in the latter case effector cells appeared earlier and were demonstrable for a longer period than in MSV-M-inoculated mice. Anti-theta serum treatment of lymphoid spleen cells taken at the stage of peak tumor size abrogated the cytotoxic activity or diminished it considerably indicating a T-lymphocyte response.

Animals↗
PubMed1987

Spleen size in patients with inflammatory bowel disease. Does it have any clinical significance?

The finding that splenic atrophy is associated with a high complication rate in colitis has led to a long-term, prospective study of spleen size in inflammatory bowel disease. The spleen has been measured in 116 patients undergoing laparotomy for inflammatory bowel disease--80 Crohn's disease and 36 ulcerative colitis--from 1975 to 1985. Small spleen size, of lesser degree than that of classic splenic atrophy, is associated with presurgery disease complications as well as infective problems after surgery. Spleen size was not related to site or extent of disease, or to recurrence, but the wide range of spleen size seen in inflammatory bowel disease, comparable to that seen in malignancy suggests that more sophisticated tests of splenic function might show a closer correlation with disease patterns.

Body Height↗
PubMed1984

Analysis of lymphoid and dendritic cells in human lymph node, tonsil and spleen. A study using monoclonal and heterologous antibodies.

The distribution of lymphoid and dendritic cells in human reactive lymph nodes, tonsils and spleens was examined by means of an indirect immunoperoxidase technique, using a panel of monoclonal and heterologous antibodies. The antibodies used were directed against antigens present on T cell subsets (Leu1, leu2a, Leu3a, TA1, OKT6), various types of B cells (BA1, BA2, HLA-DR, CR1) and cells of the mononuclear phagocyte system (alpha HM1, TA1, CR1, OKM1, NA 1/34). In the lymph node and tonsil Leu3a-positive cells (T-helper/inducer phenotype) and Leu2a-positive cells (T-suppressor/cytotoxic phenotype) are found in the thymus-dependent or T-cell area; in the spleen Leu3a-positive cells are found mostly in the periarteriolar lymphocyte sheath (PALS), while Leu2a-positive T-suppressor/cytotoxic cells are almost completely restricted to the cords of Billroth in the red pulp. The cells in the mantle zone of germinal centres and in the primary follicles in lymph nodes, tonsils and spleens have B-cell properties (BA1-, HLA-DR-, and CR1-positive). The cells in the germinal centres show a similar staining pattern (HLA-DR-, and partly CR1-positive). Follicles and T-cell-dependent areas have specific dendritic cells, each with a specific staining pattern: the dendritic reticulum cell (DRC) of the follicle stain with CR1, HLA-DR, BA2 and alpha HM1; the interdigitating cell of the T-cell areas in the lymph node, tonsil and spleen stain with HLA-DR and BA1. Moreover, large dendritic OKT6-positive cells are found in the T-cell areas of some of the peripheral lymph nodes, and are probably Langerhans cells. It is concluded that human lymph nodes and tonsils have an identical compartimentalisation, clearly differing from the spleen in cellular organization.

Antibodies, Monoclonal↗
PubMed1982

Morphometrical analysis of T- and B-cell compartments of spleens in Hodgkin's disease.

One possible explanation for the defective cellular immunity in Hodgkin's disease is an abnormal distribution of T lymphocytes. To study this possibility a morphometric analysis of T- and B-areas in non involved and involved spleens of patients with Hodgkin's disease was undertaken. We found that in involved spleens a significant reduction of the T dependent area could be demonstrated. We concluded that this reduction is caused by an abnormal distribution of T lymphocytes in the spleen and may partly explain the defects in cellular immunity. In addition, the absence of overlap between the T/B area ratios of involved and non-involved spleens suggests, that a prediction on involvement of spleen can be made by morphometrical analysis of a small, random taken non-involved area.

Adolescent↗
PubMed1995

The value of combined 99mTc-Sn-colloid and 99mTc-RBC scintigraphy in the evaluation of a wandering spleen.

Wandering spleen is the term commonly applied to splenic hypermobility that results from laxity or maldevelopment of its suspensory ligaments. It comes to medical attention usually as an abdominal mass, or when the spleen undergoes torsion. Diagnosis on clinical grounds alone is rarely made, and ultrasonography, CT and MRI findings have no specific characteristics for this condition. 99mTc-labeled colloid taken up by the spleen may provide a specific diagnosis. We report a case of wandering spleen, in which the preoperative diagnosis was made on the basis of sequential liver-spleen scintigraphy with 99mTc-Sn-colloid and blood-pool scintigraphy with 99mTc-RBC. This is a rare case, in which hypermobility was assessed by sequential 99mTc-Sn-colloid scintigraphy, and to our knowledge, is the first case in which 99mTc-RBC scintigraphy provided useful information on splenic blood volume and its location.

Adult↗
PubMed2003

[Accessory spleen in the pancreatic tail -- a neglected entity? A contribution to embryology, topography and pathology of ectopic splenic tissue].

According to autoptic studies, accessory spleens may be found in 10% to 15% of the population, in 1% to 2% they are located in the pancreatic tail. They thus have to be taken into account in the differential diagnosis of intra- and peripancreatic tumorous lesions. After splenorenal fusion, they can be found pararenally and retroperitoneally, and after splenogonadal fusion they can descend into the pelvis or scrotum. Since they usually are asymptomatic, they are mostly discovered accidentally. The diagnosis is ascertained by a scintigram with technetium-99-marked, heat-damaged red blood cells. If resection is necessary, the organ adherent to the encapsulated accessory spleen should be preserved. By means of three case reports (intrapancreatic accessory spleen, retroperitoneal accessory spleen and torsion-infarcted wandering spleen), the surgical relevance of ectopic splenic tissue is discussed.

Adult↗
PubMed2002

CD34+ progenitor cells in idiopathic (primary) myelofibrosis: a comparative quantification between spleen and bone marrow tissue.

Previous studies on idiopathic (primary) myelofibrosis (IMF) are in keeping with the finding of an increased number of circulating CD34+ progenitor cells. However, dependent on the fibrosclerotic changes, little knowledge exists about quantitative relationships of this precursor cell population in spleen and bone marrow. The purpose of this study was to determine the number of CD34+ cells at these sites by applying immunohistochemistry and morphometry. In seven patients with IMF and a control group without hematopathology (14 patients), CD34+ progenitors were identified in the red pulp of the spleen and also in bone marrow trephine biopsies by the monoclonal antibody QBEND10. Histological analysis showed no differences regarding size or cytological details of these cells at both sites in patients with IMF as well as in the controls. On the other hand, in the IMF group there was an unequal distribution with an approximate twofold increase in precursor cells in the spleen compared to the bone marrow. This result is opposed to corresponding values of the control group. Considering the quantity of progenitor cells in the normal bone marrow, no significant increase was revealed in IMF, but a marked pooling (more than fourfold of the normal value) in the spleen. In conclusion, our findings are in keeping with a increased number of splenic CD34+ progenitor cells and therefore support the hypothesis of a pronounced filtration and trapping of this precursor cell population by the spleen in IMF.

Aged↗
PubMed2004

Speed of spleen volume changes evoked by serial apneas.

Diving mammals may enhance dive duration by injecting extra erythrocytes into the circulation by spleen contraction. This mechanism may also be important for apneic duration in humans. We studied the speed and magnitude of spleen volume changes evoked by serial apneas, and the associated changes in hematocrit (Hct) and hemoglobin (Hb) concentration, diving response and apneic duration. Three maximal apneas separated by 2 min rest elicited spleen contraction in all ten subjects, by a mean of 49 (27) ml (18%; P<0.001). During the same period, Hct and Hb rose by 2.2 and 2.4% respectively (P<0.01 and P<0.001), and apneic duration rose by 20 s (22% P<0.05). The mean heart rate reduction of the diving response was 15%, which remained the same throughout the apnea series. While the diving response was completely reversed between the apneas, spleen size was not recovered until 8-9 min after the final apnea corresponding with recovery of Hct and Hb. Thus, although the spleen contraction may be associated with the cardiovascular diving response, it is likely to be triggered by different mechanisms, and it may remain activated between dives spaced by short pauses. The two adjustments may provide a fast, quickly reversed, and a slow, but long-lasting, way of shifting to a diving mode in humans.

Adaptation, Physiological↗
PubMed1999

Development of the thymus, spleen, lymph nodes and liver in the marsupial, Isoodon macrourus (Northern brown bandicoot, Peramelidae).

We report for the first time the development and morphological characteristics of the spleen thymus, lymph nodes and liver of the northern brown bandicoot, Isoodon macrourus. To date few marsupial species have been studied. The development and morphological characteristics of the organs shared the typical features of those few other marsupials studied as well as those of eutherians. These suggest comparative functional properties with the eutherian immune system. The thymus differentiated within the first week of pouch life and showed evidence of immunolymphopoiesis up to juvenile stages. The spleen, though seeded by lymphocytes within the first week of pouch life, was slower to mature, but differentiated and showed signs of immunocompetency by the time young left the pouch. The mature spleen displayed the same anatomical blood filtering and immunosurveillance properties as that of the eutherian spleen, with evidence of erythrocyte destruction, thrombopoietic activity, activation and differentiation of immunocompetent lymphocytes. However, the absence of sheathed capillary structures in the spleen may indicate differences in the humoral response to circulating antigens. Similarly, lymph nodes also mature by this stage with anterior nodes appearing before posterior nodes. The mature lymph nodes displayed structural features of secondary immuno-lymphoid organs consistent with production of immune responses. Finally, the liver displayed haemopoietic activity for the first four weeks of pouch life. The pattern of development in the bandicoot appears to parallel the pattern reported for other marsupials, yet the thymus matures considerably earlier than previously reported and may be of significance in the development and onset of cell-mediated immunity. Current studies to characterise cellular components, such as T/B lymphocyes and accessory cells of these organs will help to define the mechanisms of immune recognition, activation and hence outline the basis of the marsupial humoral and cellular immunity.

Age Factors↗