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PubMed1980

Opisthorchis viverrini: partial success in adoptively transferring immunity with spleen cells and serum in the hamster.

Three groups of golden Syrian hamsters received intraperitoneally either, (1) 1 x 10(7) spleen cells, (2) 0.5 ml. serum or, (3) 1 x 10(7) spleen cells plus 0.5 ml. serum, from donors infected 6 weeks previously with 25 Opisthorchis viverrini metacercariae, one day before and at the same time as challenge with 25 metacercariae. Three groups of control animals received the same quantities of spleen cells, serum or an admixture of both from normal non-infected donors in the same manner followed by challenge with 25 metacercariae. Animals were killed six weeks after challenge, livers and extrahepatic biliary systems carefully removed, and liver worm burdens estimated. Additionally, parasitic egg counts were performed on pooled faeces samples collected one hour prior to death. Animals receiving spleen cells, serum, or an admixture of both, from normal non-infected donors had mean worm burdens of 11.44, 12.00 and 12.66, respectively. Animals receiving spleen cells, serum, or both, from infected donors had mean worm burdens of 9.88, 7.77 and 12.00, respectively. There were no significant differences in mean worm burdens between control and experimental groups. However, a substantial reduction in parasitic faecal egg counts and subsequently mean egg production per worm was observed in all 3 groups of animals receiving spleen cells, serum, or both, from infected donors when compared to their respective control groups. These findings are discussed in relation to adoptive transfer studies performed with other helminths and their possible relevance to naturally acquired immunity is commented on.

Animals↗

PubMed1995

Effects of adoptive transfer of immune spleen cells on worm growth and microfilaraemia in Brugia pahangi infection in Mongolian gerbils.

Protective immunity against Brugia pahangi was examined after adoptive transfer of immune spleen cells. Spleen cells obtained from gerbils at 8 weeks post-infection (p.i.) with 100 infective larvae (L3) of B. pahangi were transferred into naive recipients, and then 24 h later, they were infected with 100 L3 of B. pahangi. The recipients given normal spleen cells and infected by the same manner served as controls. Microfilarial counts in the circulation were monitored at designated times after infection and worm burden and the size of individual female worm were determined at 16 weeks p.i. to evaluate the effects of adoptive immunization. In addition, eosinophil responses and serum antibody titres were examined during the course of infection. In the control group, microfilariae first appeared in circulation at 9 weeks p.i. and continuously increased in number throughout the course examined. In contrast, microfilaraemia was almost completely suppressed in the group given immune spleen cells. Although worm burden was comparable between the two groups, the average size of female adult worms recovered from the adoptively immunized group was significantly smaller than that from the control group. Eosinophil response was hastened and enhanced by adoptive transfer of immune spleen cells in the early stage of infection. Parasite-specific antibody response was also hastened by adoptive immunization. These results suggest that immune spleen cells could confer protective immunity mainly directed against adult B. pahangi.

Animals↗

PubMed1983

Stabilization of islet allografts by treatment of recipients with ultraviolet irradiated donor spleen cells.

Culture of mouse pancreatic islets in an oxygen-rich atmosphere before transplantation facilitates long-term allograft survival without the use of immunosuppression. A comparison of the capacity of ultraviolet (UV) irradiated and live spleen cells of donor origin to induce allograft rejection showed that UV-irradiated spleen cells were not immunogenic; live spleen cells were immunogenic and their injection triggered allograft rejection. Following treatment with irradiated spleen cells from about day 30 post-transplantation, recipient animals were able to withstand subsequent challenges with 10(6) and 10(7) viable donor spleen cells. Untreated animals rejected their graft when challenged with 10(6) donor spleen cells. That is, treatment with UV-irradiated cells stabilized the islet allograft by inducing a state of tolerance. Subsequent transplantation of stabilized animals with uncultured thyroids of both donor origin and from a third party strain demonstrated that the tolerance was specific. In vitro test of immune reactivity showed this tolerance was not due to the deletion of antigen reactive cells.

Animals↗

PubMed1997

The spleen, IgG antibody subsets and immunity to Plasmodium berghei in rats.

The development of IgG subclass-specific antibody responses to Plasmodium berghei in spleen-chimeric rats were monitored to determine if there was any relationship between IgG subset profiles and resistance. Strongly immune eusplenic rats respond to challenge with P. berghei by producing high levels of parasite-specific IgG2a, IgG2b and IgG2c but only modest levels of IgG1. Splenectomy profoundly affects the antibody response to infection. Thus, in splenectomized immunized rats, which harbour a chronic parasitaemia of 1%, the IgG2a, IgG2b and IgG2c responses peak 1 week later than in eusplenic immunized rats although the size of the peak is similar. More marked effects are apparent in the IgG1 response, the magnitude of which is far greater in splenectomized immunized rats than eusplenic immunized rats. Similar antibody profiles are seen in splenectomized immunized rats transplanted with a naive spleen. In contrast, splenectomized naive rats receiving either a transplant of a spleen from an immune rat or a transfer of immune spleen cells have high levels of IgG2a, IgG2b and IgG2c but modest levels of IgG1. However, only the former group of rats completely clears the parasite, the latter maintaining a chronic 1% parasitaemia. Thus, although complete resistance to P. berghei is always associated with high levels of parasite-specific IgG2a, IgG2b and IgG2c plus modest levels of IgG1, this is not a sufficient set of conditions to guarantee complete immunity. The IgG subset profile may be related to cytokine production; IFN-gamma was detected in the sera of rats receiving spleens from rats immune to P. berghei (modest IgG1 responses) but not in rats receiving spleens from naive animals (pronounced IgG1 responses).

Adoptive Transfer↗

PubMed2004

Flow cytometric analysis of normal and reactive spleen.

Spleen is surgically removed for both non-neoplastic and neoplastic pathologies. A significant proportion of splenectomy specimens require distinguishing between reactive and neoplastic conditions (eg lymphoma). To establish a 'normal' reference range for the spleen lymphocyte subsets, fresh samples of benign, reactive spleens obtained from adult patients (N=12) and samples of normal spleen obtained from cadaveric transplant donors (N=14) were analyzed using three- and four-color flow cytometry. Study of pan-B, -T, and -NK marker expression revealed that the frequency of T cells is higher and that of B cells is lower in reactive (non-neoplastic) compared to normal (cadaveric) spleen. Furthermore, our study established a frame of reference for cell markers commonly used for immunophenotyping of lymphoma, and identified discrete lymphocyte subsets, such as early plasma cells and T cells carrying the phenotype of the NK/T subset. These results will facilitate an accurate interpretation of the flow cytometric analysis of human spleen lymphocytes.

Adolescent↗

PubMed1989

Purification of chicken liver ferritin by two novel methods and structural comparison with horse spleen ferritin.

Ferritin was purified from chicken liver by two different methods: gel filtration on controlled-pore glass beads, and immunoaffinity chromatography employing a chicken ferritin-specific monoclonal antibody that did not cross-react with horse spleen ferritin. This antibody recognizes intact ferritin and an oligomeric 240 kDa form of the molecule after protein transfer to nitrocellulose, but not the 22 kDa chicken ferritin subunit. Chicken liver ferritin purified by these methods exhibited reduced migration on non-denaturing polyacrylamide gels compared with horse spleen ferritin. These results were consistent with the difference in calculated isoelectric points of chicken and horse ferritin subunits. By two-dimensional gel electrophoresis, chicken ferritin 22 kDa subunits exhibited isoelectric points from 6.1 to 6.6 whereas horse spleen ferritin subunits exhibited isoelectric points of 5.8-6.3. The 240 kDa form of the chicken ferritin molecule had an isoelectric point of 6.6 whereas the 210 kDa form of the horse ferritin molecule had isoelectric points of 5.1 and 4.9. Intact chicken liver ferritin particles were 13.4 +/- 0.8 nm (controlled-pore glass-purified) and 12.5 +/- 0.9 nm (affinity-purified) in diameter when viewed by electron microscopy. Horse spleen ferritin consisted of slightly smaller particles with an average diameter of 11.0 +/- 0.7 nm. However, ferritin from chicken liver and horse spleen co-migrated with an apparent molecular mass of 470 kDa when analysed by Sepharose 4B gel filtration chromatography. These results indicate that, consistent with results from other published purification methods, the chicken ferritin purified by the methods reported here exhibits both structural similarities to, and differences from, horse spleen ferritin.

Animals↗

PubMed1991

Reverse cholesterol transport in the rat. Studies using the isolated perfused spleen in conjunction with the perfused liver.

1. A new method combining the use of an isolated perfused extrahepatic tissue with a perfused liver was developed as a model system for the study of reverse cholesterol transport. Rat spleens, initially labelled in vivo with [3H]cholesterol, were perfused for 3 h with whole blood. The spleen was then replaced with an isolated rat liver, whose uptake of cholesterol from the spleen-derived blood and excretion of cholesterol into bile constituents were determined. 2. During spleen perfusion, a net release of cholesterol mass and radioactivity to lipoproteins was observed. 3. During liver perfusion, there was also a rapid exchange or transport of unesterified cholesterol between high-density lipoprotein (HDL) and the liver, in particular with HDL2 (d = 1.085-1.125). 4. The liver showed an increased uptake of cholesteryl ester from serum that had previously been used in spleen perfusion. 5. Approximately half of the [3H]cholesterol released by the spleen was recovered in erythrocytes. During subsequent liver perfusion there was a substantial uptake of radioactivity from the erythrocytes, although less than that recorded from serum lipoproteins. 6. In all experiments there was significant excretion of [3H]cholesterol into bile; most (85%) was in bile acids. Thus the complete process of reverse cholesterol transport is observed in this dual-perfusion system.

Animals↗

PubMed1993

Effect of splenic congestion associated with haemolytic anaemia on filtration of 'spleen-homing' microspheres.

1. The surface of large model 125I-labelled polystyrene microspheres (220 nm in diameter) was coated with the polyoxyethylene/polyoxypropylene block co-polymer poloxamine-908. The coated microspheres were injected intravenously into rats. Up to 40% of the administered dose had accumulated in the spleen by a filtration mechanism, as compared with 5% for uncoated microspheres, at 3 h after administration. The enhanced splenic sequestration of microspheres was accompanied by a decrease in the liver uptake. In contrast, smaller poloxamine-908-coated microspheres (60 nm in diameter) effectively avoided uptake by both the liver and the spleen and remained in systemic circulation. 2. The effect of splenic congestion, associated with phenylhydrazine-induced haemolytic anaemia, on filtration of poloxamine-908-coated microspheres was studied. The enlarged spleen of the anaemic rats was incapable of efficiently filtering large poloxamine-908-coated microspheres when compared with the spleen of normal animals. This was suggested to be the result of extensive 'clogging' of the red pulp by damaged erythrocytes. However, the splenic filtration of large coated microspheres was still five-fold higher than that of uncoated microspheres of similar size in anaemic animals. 3. The potential use of large sterically stabilized colloids and drug carriers for selective spleen scanning and splenic drug delivery in pathological conditions, where anaemia prevails, is discussed. 4. Sterically stabilized microspheres may have potential for re-examining the microcirculatory pathways in healthy spleen and various splenomegalies.

Anemia, Hemolytic↗

PubMed2001

The age-related immunity in cattle to Babesia bovis infection involves the rapid induction of interleukin-12, interferon-gamma and inducible nitric oxide synthase mRNA expression in the spleen.

Young calves possess a strong innate immunity against Babesia bovis infection that lasts for approximately 6 months after birth and is abrogated with the removal of the spleen. This immunity is characterized as cellular involving a soluble mediator. Nitric oxide has been implicated by virtue of its babesiacidal affects in vitro, but questioned to be as effective in vivo, due to its ability to downregulate type-1 immunity. Spleen cells were obtained from 4-month-old calves and adult steers and processed for monitoring cytokine and inducible nitric oxide synthase (iNOS) mRNA expression during the response to initial B. bovis infection. The data provided evidence of a transient role for nitric oxide in innate immunity, characterized by brief iNOS induction in the spleen of calves that was not detectable in the spleens of adults. The iNOS message followed the early induction of interleukin (IL)-12 and interferon (IFN)-gamma message in calves. The induction of IL-12 and IFN-gamma message in adults was delayed until IL-10 message was induced. Transformation growth factor-beta mRNA expression levels were greater in spleen cells from adults early in infection and then declined, whereas expression levels increased in spleen cells from calves later in the infection process. Together, the data support the concept of 'first come, first serve' cytokine influence over cellular activities, the importance of a type-1 response in the control of an initial infection and the need for tight regulation in order to prevent pathology associated with over production of nitric oxide and inflammatory cytokines.

Age Factors↗

PubMedDate not supplied

Uneven changes in circulating blood cell counts with adrenergic stimulation to the canine spleen.

1. Responses of splenic diameter measured by sonomicrometry to alpha- and beta-adrenoceptor stimulants were estimated together with simultaneously measured systemic arterial and splenic venous concentrations of red blood cells (RBC), white blood cells (WBC) and platelets (PLT) in anaesthetized dogs. 2. Intravenous and intrasplenic arterial injections of adrenaline, noradrenaline and phenylephrine all produced profound decreases in splenic diameter. Increases in systemic arterial concentrations of RBC produced by these stimulants were observed immediately following the splenic contraction and marked increases in splenic venous concentration of RBC. 3. Adrenaline and noradrenaline both caused rapid and transient decreases in WBC release from the spleen and these agonists then, in addition to phenylephrine, caused gradual and small increases in systemic arterial WBC concentrations. The increases in arterial RBC and WBC concentrations were abolished by transient isolation of the spleen from the systemic circulation. These three agents did not significantly modify differences between splenic venous and systemic arterial concentrations of PLT. 4. Intra-arterial injections of isoprenaline caused an increase in splenic diameter and a significant decrease in the splenic venous concentration of WBC, but barely influenced the veno-arterial differences in RBC and PLT concentrations across the spleen. 5. The present results indicate that contraction of the spleen through stimulation of splenic alpha1-adrenoceptors contributes to supplying RBC but not PLT into the systemic circulation, whereas splenic beta-adrenoceptor activation leads to splenic dilatation with increased sequestration of WBC to the spleen despite no changes in the release of RBC and PLT from the spleen.

Adrenergic Agonists↗

PubMed2000

Production and release of endothelin-1 from the gut and spleen in portal hypertension due to cirrhosis.

This study was aimed to evaluate the source of endothelin-1 (ET-1) in cirrhotic patients. ET-1 is implicated in the pathogenesis of portal hypertension. However, the mechanism and source for increased plasma ET-1 in cirrhotic patients are still obscure. Plasma ET-1 levels in systemic (SV), superior mesenteric (SMV), and splenic venous (SPV) blood were measured in 23 patients with cirrhosis and 8 controls with normal liver. Fourteen removed spleens were immunohistochemically studied for ET-1, CD34, CD68, and CD20. In situ hybridization was done to localize ET-1 messenger RNA (mRNA). In cirrhosis, ET-1 levels in both SMV and SPV were higher than in SV. ET-1 in SV and SPV were significantly higher in cirrhotic patients than in control patients. Three groups of cells in the spleen expressed both protein and mRNA of ET-1: endothelial cells in the sinus, which were also stained for CD34; cells in the germinal center; and cells in the marginal zone of lymphoid sheaths and follicles, which were also stained for CD20 but not for CD34 and CD68. The ET-1 concentration released from the spleen was in parallel with the grade of ET-1 expression in the spleen. The spleen is one of the major sites of ET-1 release in cirrhotic patients. Endothelial cells of the splenic sinus and possibly B lymphocytes in the germinal center and marginal zone of lymphoid sheaths and follicles seem to be the sites of ET-1 production in the spleen.

Adult↗

PubMed2006

Multiple lesions of the spleen: differential diagnosis of cystic and solid lesions.

Lesions in the spleen may be encountered in a variety of clinical settings ranging from asymptomatic patients to patients who are critically ill. Etiologies for multifocal splenic lesions include infectious and inflammatory processes, primary vascular and lymphoid neoplasms, metastatic disease, vascular processes, and systemic diseases. There is often overlap in the imaging appearance alone, so the clinical setting is very helpful in differential diagnosis. In the immunocompromised patient, multiple small splenic lesions usually represent disseminated fungal disease and microabscesses. The spleen is a relatively rare site for metastatic disease; patients with metastatic lesions in the spleen usually have disease in other sites as well. Breast, lung, ovary, melanoma, and colon cancer are common primary tumors that metastasize to the spleen. Vascular neoplasms of the spleen represent the majority of the nonhematologic/nonlymphoid neoplasms and commonly produce multifocal lesions. Splenic infarcts may be seen with localized processes such as portal hypertension or pancreatitis, or may arise from an embolic source. Radiologists should be aware of the spectrum of processes that may involve the spleen and the clinical context in which they occur.

Abscess↗

PubMed1999

Distribution of T-lymphocyte subpopulation in blood and spleen of normal cattle and cattle with enzootic bovine leukosis.

Immunocytochemical and flow cytometry techniques were used to examine T-lymphocyte subpopulations in peripheral blood lymphocytes (PBLs) and spleen from cases of enzootic bovine leukosis (EBL) in adult cattle, and from normal cattle (adult and young), with a panel of monoclonal antibodies against bovine leucocyte differentiation molecules. Both in PBLs and spleen, the percentages of T-lymphocyte subpopulations (CD3+, CD4+, CD8+, and WC1 + gamma delta T lymphocytes) of EBL-affected and normal adult cattle were significantly lower than those of normal young cattle. The percentages of these T-lymphocyte subpopulations in the PBLs of adult cattle with EBL were lower than those of normal adult cattle, but the converse was true in the spleen. It is suggested that tumour immunity occurred in the spleen. Histological examination revealed no follicular hyperplasia in the spleen, and the proliferation of neoplastic cells began in the red pulp. It is concluded that the spleen is not the organ initially responsible for the transformation of EBL lymphoma and that neoplastic cells migrating from peripheral blood are metastatic.

Age Factors↗

PubMed2002

Minilaparoscopy-guided spleen biopsy in systemic disease with splenomegaly of unknown origin.

With the advent of a minimally invasive laparoscopy technique, the advantages of diagnostic laparoscopy are being rediscovered. We report here on four patients with systemic disease of unknown origin and splenomegaly, in whom minilaparoscopy-guided splenic biopsy yielded a definitive diagnosis. Four patients with unclear systemic disease were studied using diagnostic minilaparoscopy and guided spleen biopsy, after failure of diagnostic work-up. Minilaparoscopic spleen biopsy revealed the diagnosis of a B-cell non-Hodgkin's lymphoma in two cases. In one patient, who had a history of Still's disease, the spleen biopsy showed granulocytic infiltration in the spleen typical of an acute episode of Still's disease. One patient with a known immunodeficiency syndrome (stage C III) showed multiple hypodense lesions in the spleen. Biopsy allowed a diagnosis of mycobacterial infection, with identification of Mycobacterium tuberculosis. No major complications occurred in any of the four cases; post-biopsy bleeding was observed in three of the four, but was easily managed by argon plasma coagulation or application of fibrin glue, or both. We recommend the use of spleen biopsy as a diagnostic tool in splenopathy of unknown origin if previous diagnostic methods have failed to yield a definitive diagnosis.

Acquired Immunodeficiency Syndrome↗

PubMed2006

Correction of hemophilia as a proof of concept for treatment of monogenic diseases by fetal spleen transplantation.

Previous clinical attempts to correct genetic deficiencies such as hemophilia or Gaucher disease by transplantation of allogeneic spleen were associated with aggressive graft versus host disease, mediated by mature T cells derived from the donor spleen. We show that a fetal pig spleen harvested at the embryonic day 42 stage, before the appearance of T cells, exhibited optimal growth potential upon transplantation into SCID mice, and the growing tissue expressed factor VIII. Transplantation of embryonic day 42 spleen tissue into hemophilic SCID mice led to complete alleviation of hemophilia within 2-3 months after transplant, as demonstrated by tail bleeding and by assays for factor VIII blood levels. These results provide a proof of principle to the concept that transplantation of a fetal spleen, obtained from a developmental stage before the appearance of T cells, could provide a novel treatment modality for genetic deficiencies of an enzyme or a factor that can be replaced by the growing spleen tissue.

Animals↗

PubMed1969

The role of individual spleen cells in the interferon response of the intact mouse.

A method is described for the detection of interferon production by individual spleen cells of mice after intravenous virus infection. Although mouse spleen plays a major role in the total interferon response to Newcastle disease virus, the number of spleen cells participating is a small fraction of the total, suggesting that interferon formation is to some extent a specialized cell function. Monolayers of mouse embryo cells, after brief contact with agar-suspended spleen cells from interferon-producing mice, have roughly circular foci of cells remaining after removal of agar and vesicular stomatitis virus challenge. The numbers of such foci correlate directly with the number of spleen cells, concentration of inducing virus in the inoculum, duration of contact of cells with mouse-embryo indicator monolayers, time after interferon induction, and serum interferon titer. With this technique, evolution of the interferon-forming cell response in spleens of virus-infected mice has been studied.

Animals↗

PubMed1975

Lysis of leukemia cells by spleen cells of normal mice.

Spleen cells from 2- to 3-month-old normal mice of some strains having a low incidence of spontaneous leukemia were found to lyse cells of the spontaneous AKR leukemia K36 in the 51Cr release assay. Incubation of 51Cr-labeled ADR K36 cells with spleen cells from normal C57BL/6, C57L, C57BL/10, and RF mice resulted in the release of significantly more 51Cr than that released in the presence of medium alone. In contrast, 51Cr released from AKR K36 cells after incubation with spleen cells from mice of the high leukemic strains AKR and C58 was less than that released spontaneously. The results of competitive inhibition tests when C57BL/6 spleen cells were incubated simultaneously with 51Cr-labeled AKR K36 target cells and varying numbers of nonlabeled cells demonstrated that the cytotoxic activity of normal C57BL/6 spleen cells was directed against an antigen(s) associated with several leukemias, but that was undetectable on normal thymocytes. Pretreatment of C57BL/6 spleen cells with carbonyl iron and a magnet, which removed phagocytic macrophages, did not decrease the cytotoxic acitivity for AKR K36 cells.

Animals↗

PubMed1996

Trafficking of Plasmodium chabaudi adami-infected erythrocytes within the mouse spleen.

Plasmodium chabaudi adami causes a nonlethal infection in mice. We found that crisis, the time of rapidly dropping parasitemia, was abrogated by splenectomy, indicating the role of spleen in parasite killing. The factors that mediate spleen-dependent immunity are not known. An earlier study in Plasmodium berghei-infected rats showed an association between increased clearance of heat-treated erythrocytes and the onset of crisis [Wyler, D. J., Quinn, T. C. & Chen, L.-T. (1982) J. Clin. Invest. 67, 1400-1404]. To determine the potential effects of different vascular beds in parasite killing, we studied the distribution of parasitized erythrocytes and bacteria in the spleens of P. chabaudi adami-infected mice during precrisis (a period of rising parasitemia) and during crisis. After intravenous injection, bacteria were localized predominantly in the marginal zone. In contrast, parasitized erythrocytes were found in the red pulp. We also found that during precrisis, a time of no immunity, the uptake of radiolabeled infected erythrocytes by the spleen was increased, not decreased. These data imply that no change occurs in the flow of parasitized erythrocytes through the spleen during the transition to an immune state (crisis). Our observations suggest that immune effector mechanisms, not circulatory changes, account for spleen-dependent parasite killing during a P. chabaudi adami infection in mice.

Animals↗