Reconstructing spleno-mesenterico-portal cofluence by bifurcated allogeneic vein in local advanced pancreatic cancer-a feasible method to avoid left-sided portal hypertension

BACKGROUND

Left-sided portal hypertension is usually found in patients undergoing pancreaticoduodenectomy (PD) with spleno-mesenterico-portal (S-M-P) confluence resection. This study is to explore the outcomes of S-M-P confluence reconstruction after resection by using bifurcated allogeneic vein.

METHODS

Clinicopathologic data of patients who underwent extensive PD with S-M-P confluence resection for carcinoma of pancreatic head/uncinate process in our hospital between December 2011 and August 2018 were retrospectively reviewed and clinical outcomes of vein reconstruction after resection were analyzed.

RESULTS

Of the 37 patients enrolled, S-M-P reconstruction by bifurcated allogeneic vein was performed in 24 cases (group 1) and simply splenic vein ligation in 13 cases (group 2). Items including pathological results, blood loss, and complications were comparable between the two groups, operation time was longer in group 1 (573.8 vs. 479.2 min, p = 0.018). Significantly decreased platelet count (205.9 vs. 133.1 × 109 /L, p = 0.001) and increased splenic volume (270.9 vs. 452.2 ml, p < 0.001) were observed in group 2 at 6 months after operation. The mean splenic hypertrophy ratio was 1.06 in group 1 and 1.63 in group 2, respectively (p < 0.001). There were four patients with varices were found in group 2, none in group 1.

CONCLUSIONS

Without increased complications, reconstructing S-M-P confluence by bifurcated allogeneic vein after resection may help to avoid left-sided portal hypertension.

Interleukin-4 Administration or Zinc Supplementation Is Effective in Preventing Zinc Deficiency-Induced Hemolytic Anemia and Splenomegaly

Nutritional zinc deficiency aggravates inflammation, subsequently causing anemia and splenomegaly in rats; however, the mechanism underlying such splenomegaly remains poorly understood. Therefore, in this study, we aimed to elucidate the mechanisms underlying the splenomegaly and anemia occurring in zinc-deficient rats and investigate whether these effects of zinc deficiency could be reversed by interleukin (IL)-4 administration or zinc supplementation. Five-week-old male Sprague-Dawley rats were fed a standard diet; fed a zinc-deficient diet (n = 7 each) and injected with saline or IL-4; or fed a zinc-deficient diet for 6 weeks followed by a standard diet for 4 weeks thereafter. White blood cells, segmented neutrophils, platelets, CD4⁺ T cells, CD11b/c⁺ granulocytes, CINC/GRO⁺ cells, and myeloperoxidase-positive cells in the blood and spleen of the zinc-deficient rats were significantly higher than those in all the other groups. Conversely, red blood cells, hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, lymphocytes, and CD8⁺ T cells in the blood of the zinc-deficient rats were significantly lower than those in the other groups. Furthermore, serum aspartate aminotransferase, lactate dehydrogenase, indirect bilirubin concentrations, and erythrocyte osmotic fragility in the zinc-deficient rats were significantly higher than those in the other groups. Moreover, zinc deficiency significantly decreased the GATA1 protein levels in the spleen. Collectively, these results indicate that zinc deficiency aggravates the inflammatory response and causes hemolytic anemia and splenomegaly. Importantly, IL-4 administration and zinc supplementation can reverse the zinc deficiency-induced hemolytic anemia and splenomegaly.

Quaternary Ammonium Compound Disinfectants Reduce Lupus-Associated Splenomegaly by Targeting Neutrophil Migration and T-Cell Fate

Hypersensitivity reactions and immune dysregulation have been reported with the use of quaternary ammonium compound disinfectants (QACs). We hypothesized that QAC exposure would exacerbate autoimmunity associated with systemic lupus erythematosus (lupus). Surprisingly, however, we found that compared to QAC-free mice, ambient exposure of lupus-prone mice to QACs led to smaller spleens with no change in circulating autoantibodies or the severity of glomerulonephritis. This suggests that QACs may have immunosuppressive effects on lupus. Using a microfluidic device, we showed that ambient exposure to QACs reduced directional migration of bone marrow-derived neutrophils toward an inflammatory chemoattractant ex vivo. Consistent with this, we found decreased infiltration of neutrophils into the spleen. While bone marrow-derived neutrophils appeared to exhibit a pro-inflammatory profile, upregulated expression of PD-L1 was observed on neutrophils that infiltrated the spleen, which in turn interacted with PD-1 on T cells and modulated their fate. Specifically, QAC exposure hindered activation of splenic T cells and increased apoptosis of effector T-cell populations. Collectively, these results suggest that ambient QAC exposure decreases lupus-associated splenomegaly likely through neutrophil-mediated toning of T-cell activation and/or apoptosis. However, our findings also indicate that even ambient exposure could alter immune cell phenotypes, functions, and their fate. Further investigations on how QACs affect immunity under steady-state conditions are warranted.

Pathologic angiogenesis in the bone marrow of humanized sickle cell mice is reversed by blood transfusion

Sickle cell disease (SCD) is a monogenic red blood cell (RBC) disorder with high morbidity and mortality. Here, we report, for the first time, the impact of SCD on the bone marrow (BM) vascular niche, which is critical for hematopoiesis. In SCD mice, we find a disorganized and structurally abnormal BM vascular network of increased numbers of highly tortuous arterioles occupying the majority of the BM cavity, as well as fragmented sinusoidal vessels filled with aggregates of erythroid and myeloid cells. By in vivo imaging, sickle and control RBCs have significantly slow intravascular flow speeds in sickle cell BM but not in control BM. In sickle cell BM, we find increased reactive oxygen species production in expanded erythroblast populations and elevated levels of HIF-1α. The SCD BM exudate exhibits increased levels of proangiogenic growth factors and soluble vascular cell adhesion molecule-1. Transplantation of SCD mouse BM cells into wild-type mice recapitulates the SCD vascular phenotype. Our data provide a model of SCD BM, in which slow RBC flow and vaso-occlusions further diminish local oxygen availability in the physiologic hypoxic BM cavity. These events trigger a milieu that is conducive to aberrant vessel growth. The distorted neovascular network is completely reversed by a 6-week blood transfusion regimen targeting hemoglobin S to <30%, highlighting the plasticity of the vascular niche. A better insight into the BM microenvironments in SCD might provide opportunities to optimize approaches toward efficient and long-term hematopoietic engraftment in the context of curative therapies.

Chronic myeloid leukemia patients in Tunisia: epidemiology and outcome in the imatinib era (a multicentric experience)

Data are limited in developing countries regarding the clinicopathologic features and response to therapy of chronic myeloid leukemia (CML) in the era of imatinib (IM). The objective of this study is to report on the clinicoepidemiologic features of CML in Tunisia, to evaluate the long-term outcome of patients in chronic (CP) or accelerated phase (AP) treated with IM 400 mg daily as frontline therapy, and to determine imatinib's efficacy and safety. From October 2002 to December 2014, 410 CML patients were treated with IM in six Tunisian departments of hematology. Response (hematologic, cytogenetic, and molecular responses) and outcome-overall survival (OS), event-free survival (EFS), and progression-free survival (PFS)-were evaluated. The following prognostic factors were analyzed for their impact on the European leukemia net (ELN) response, OS, EFS, and PFS at 5 years: age, sex, leukocyte count, Sokal score, European Treatment and Outcome Study (EUTOS) score, CML phase, time to starting IM, and impact of adverse events. The median age was 45 years (3-85 years). Two hundred ten (51.2%) patients were male. Splenomegaly was present in 322 of the 410 (79%). Additional cytogenetic abnormalities were encountered in 25 (6.3%) patients. At diagnosis, 379 (92.4%) patients were in CP, 31 (7.6%) were in AP. The Sokal risk was low in 87 (22.5%), intermediate in 138 (35.7%), and high in 164 patients (41.9%). The EUTOS risk was low in 217 (74%), and high in 77 (26%) patients. The rates of cumulative complete cytogenetic response (CCyR), major molecular response (MMR), and molecular response 4/5 log (MR4.5) in CP/AP-CML patients were 72, 68.4, and 46.4%, respectively. The median time to reach CCyR, MMR, and MR4.5 was 6 months (3-51), 18 months (3-72), and 24 months (3-100), respectively. According to the ELN criteria, optimal, suboptimal response, and failure were noted in 206 (51.8%), 61 (15.3%), and 125 (31.4%) patients, respectively. Five-year event-free survival (EFS), progression-free survival (PFS), and overall survival (OS) were 81, 90, and 90%, respectively. By multivariate analysis, AP, high EUTOS risk, and baseline WBC ≥ 150G/l remained independent predictive factors of non-optimal response to IM. The adverse events (AE) of IM were moderate and tolerable. With the caveats that the monitoring of the disease was not optimal, response rates were similar to those reported in previous studies. It is clear to us that improvements should be made in treatment of AP-CML and high Sokal risk group of CP-CML. The frontline use of second-generation tyrosine kinase inhibitor (TKI) is expected to improve the results of the first-line treatment of these high-risk Tunisian patients, but cost and accessibility of this therapy remain the problems in developing countries.

GABAergic modulation with classical benzodiazepines prevent stress-induced neuro-immune dysregulation and behavioral alterations

OBJECTIVE

Psychosocial stress is associated with altered immunity, anxiety, and depression. Repeated social defeat (RSD), a model of social stress, triggers egress of inflammatory myeloid progenitor cells (MPCs; CD11b(+)/Ly6C(hi)) that traffic to the brain, promoting anxiety-like behavior. In parallel, RSD enhances neuroinflammatory signaling and long-lasting social avoidant behavior. Lorazepam and clonazepam are routinely prescribed anxiolytics that act by enhancing GABAergic activity in the brain. Besides binding to the central benzodiazepine binding site (CBBS) in the central nervous system (CNS), lorazepam binds to the translocator protein (TSPO) with high affinity causing immunomodulation. Clonazepam targets the CBBS and has low affinity for the TSPO. Here the aims were to determine if lorazepam and clonazepam would: (1) prevent stress-induced peripheral and central inflammatory responses, and (2) block anxiety and social avoidance behavior in mice subjected to RSD.

METHODS

C57/BL6 mice were divided into experimental groups, and treated with either lorazepam (0.10mg/kg), clonazepam (0.25mg/kg) or vehicle (0.9% NaCl). Behavioral data and tissues were collected the morning after the last cycle of RSD.

RESULTS

Lorazepam and clonazepam were effective in attenuating mRNA expression of CRH in the hypothalamus and corticosterone in plasma in mice subjected to RSD. Both drugs blocked stress-induced levels of IL-6 in plasma. Lorazepam and clonazepam had different effects on stress-induced enhancement of myelopoiesis and inhibited trafficking of monocytes and granulocytes in circulation. Furthermore, lorazepam, but not clonazepam, inhibited splenomegaly and the production of pro-inflammatory cytokines in the spleen following RSD. Additionally, lorazepam and clonazepam, blocked stress-induced accumulation of macrophages (CD11b(+)/CD45(high)) in the CNS. In a similar manner, both lorazepam and clonazepam prevented neuroinflammatory signaling and reversed anxiety-like and depressive-like behavior in mice exposed to RSD.

CONCLUSION

These data support the notion that lorazepam and clonazepam, aside from exerting anxiolytic and antidepressant effects, may have therapeutic potential as neuroimmunomodulators during psychosocial stress. The reversal of RSD-induced behavioral outcomes may be due to the enhancement of GABAergic neurotransmission, or some other off-target effect. The peripheral actions of lorazepam, but not clonazepam, seem to be mediated by TSPO activation.

Antitoxic Activity of Extract from Salix Viminalis Leaves under Conditions of 5-Fluorouracil Treatment

Injection of 5-fluorouracil to animals caused a pronounced toxic effect. Therapeutic and preventive treatment with Salix viminalis leaf extract significantly reduced the negative effects of the antitumor drug: promoted recovery of the bone marrow, peripheral blood, and visceral parameters and prevented ulceration. Combined use of the cytostatic and Salix viminalis extract increased the efficiency of antitumor therapy.

von Willebrand Factor-Rich Platelet Thrombi in the Liver Cause Sinusoidal Obstruction Syndrome following Oxaliplatin-Based Chemotherapy

Oxaliplatin-based chemotherapy is widely used to treat advanced colorectal cancer (CRC). Sinusoidal obstruction syndrome (SOS) due to oxaliplatin is a serious type of chemotherapy-associated liver injury (CALI) in CRC patients. SOS is thought to be caused by the sinusoidal endothelial cell damage, which results in the release of unusually-large von Willebrand factor multimers (UL-VWFMs) from endothelial cells. To investigate the pathophysiology of CALI after oxaliplatin-based chemotherapy, we analyzed plasma concentration of von Willebrand factor (VWF) and the distribution of VWFMs in CRC patients. Twenty-three patients with advanced CRC who received oxaliplatin-based chemotherapy with (n = 6) and without (n = 17) bevacizumab were analyzed. CALI (n = 6) and splenomegaly (n = 9) were found only in patients who did not treated with bevacizumab. Plasma VWF antigen (VWF:Ag) and serum aspartate aminotransferase (AST) levels increased after chemotherapy only in patients without bevacizumab. VWFM analysis in patients who did not receive bevacizumab showed the presence of UL-VWFMs and absence of high molecular weight VWFMs during chemotherapy, especially in those with CALI. In addition, plasma VWF:Ag and AST levels increased after chemotherapy in patients with splenomegaly (n = 9), but not in patients without splenomegaly (n = 14). Histological findings in the liver tissue of patients who did not receive bevacizumab included sinusoidal dilatation and microthrombi in the sinusoids. Many microthrombi were positive for both anti-IIb/IIIa and anti-VWF antibodies. Plasma UL-VWFM levels might be increased by damage to endothelial cells as a result of oxaliplatin-based chemotherapy. Bevacizumab could prevent CALI and splenomegaly through inhibition of VWF-rich platelet thrombus formation.

CD47 deficiency ameliorates autoimmune nephritis in Fas(lpr) mice by suppressing IgG autoantibody production

CD47, a self-recognition marker, plays an important role in both innate and adaptive immune responses. To explore the potential role of CD47 in activation of autoreactive T and B cells and the production of autoantibodies in autoimmune disease, especially systemic lupus erythematosus (SLE), we have generated CD47 knockout Fas(lpr) (CD47(-/-) -Fas(lpr) ) mice and examined histopathological changes in the kidneys, cumulative survival rates, proteinuria, extent of splenomegaly and autoantibodies, serum chemistry and immunological parameters. In comparison with Fas(lpr) mice, CD47(-/-) -Fas(lpr) mice exhibit a prolonged lifespan and delayed autoimmune nephritis, including glomerular cell proliferation, basement membrane thickening, acute tubular atrophy and vacuolization. CD47(-/-) -Fas(lpr) mice have lower levels of proteinuria, associated with reduced deposition of complement C3 and C1q, and IgG but not IgM in the glomeruli, compared to age-matched Fas(lpr) mice. Serum levels of antinuclear antibodies and anti-double-stranded DNA antibodies are significantly lower in CD47(-/-) -Fas(lpr) than in Fas(lpr) mice. CD47(-/-) -Fas(lpr) mice also display less pronounced splenomegaly than Fas(lpr) mice. The mechanistic studies further suggest that CD47 deficiency impairs the antigenic challenge-induced production of IgG but not IgM, and that this effect is associated with reduction of T follicular cells and impairment of germinal centre development in lymphoid tissues. In conclusion, our results demonstrate that CD47 deficiency ameliorates lupus nephritis in Fas(lpr) mice via suppression of IgG autoantibody production.

High-mobility group box 1 mediates persistent splenocyte priming in sepsis survivors: evidence from a murine model

Severe sepsis is a life-threatening complication of infection and injury affecting more than 700,000 people in the United States each year. Two thirds of patients with severe sepsis will survive to be discharged. Survivors have high incidence of cognitive impairment, immune dysregulation, functional impairments with marked disability, and 5-year mortality rates of 82%. High-mobility group box 1 (HMGB1) is necessary and sufficient mediator of sepsis pathogenesis in experimental models of this syndrome. The spleen is a crucial organ in the immune response to severe infection, and splenocyte dysfunction occurs in sepsis survivors. We hypothesized that HMGB1 plays a key role in mediating the immune dysfunction of splenocytes in sepsis survivors. Mice that survived cecal ligation and puncture-induced sepsis develop persistent splenomegaly; furthermore, splenocytes derived from sepsis survivors had enhanced responses to lipopolysaccharide ex vivo. Administration of neutralizing anti-HMGB1 antibody to sepsis survivors attenuated development of splenomegaly and reversed splenocyte priming. Splenocytes exposed to HMGB1 and subsequently challenged with cognate ligands to Toll-like receptor 2 (TLR2,) TLR4, TLR9, and RAGE (receptor for advanced glycation end product) receptors had enhanced cytokine release as compared with splenocytes not previously exposed to HMGB1. Exposure of TLR2, TLR9, or RAGE splenocytes to HMGB1 enhanced responses to other TLR receptor ligands; in contrast, HMGB1 failed to prime TLR4 splenocytes. These findings indicate that exposure to HMGB1 enhances splenocyte responses to secondary inflammatory challenges, a priming effect dependent on TLR4, and that anti-HMGB1 monoclonal antibody may be beneficial in sepsis survivors.

Active immune response protects Stat6VT transgenic mice from developing a lymphoproliferative disorder

Stat6 is a transcription factor that regulates important cellular processes such as proliferation, differentiation, and survival through mediating IL-4 and IL-13 signaling. Importantly, increasing evidence indicates of a role for Stat6 in lymphoproliferative disorders. Mice expressing a constitutively active form of Stat6 (Stat6VT) primarily in T lymphocytes were generated, and it has been recently described that a small percentage (approximately 5%) of these mice develop a spontaneous lymphoproliferative disorder (LPD) resulting in dramatic splenomegaly and altered splenic cell populations. Here, we report that Stat6VT mice housed in a non-pathogen-free environment have an increased incidence (37%) of the LPD. Additionally, examination of the expression of Stat6-regulated genes known to have roles in tumorigenesis demonstrated that there appears to be no one genetic alteration common to lymphocytes from Stat6VT/LPD mice. Interestingly, however, uniform exposure to antigen via immunization resulted in complete abrogation of the LPD in Stat6VT mice.

Process and effects of a community intervention on malaria in rural Burkina Faso: randomized controlled trial

BACKGROUND

In the rural areas of sub-Saharan Africa, the majority of young children affected by malaria have no access to formal health services. Home treatment through mothers of febrile children supported by mother groups and local health workers has the potential to reduce malaria morbidity and mortality.

METHODS

A cluster-randomized controlled effectiveness trial was implemented from 2002-2004 in a malaria endemic area of rural Burkina Faso. Six and seven villages were randomly assigned to the intervention and control arms respectively. Febrile children from intervention villages were treated with chloroquine (CQ) by their mothers, supported by local women group leaders. CQ was regularly supplied through a revolving fund from local health centres. The trial was evaluated through two cross-sectional surveys at baseline and after two years of intervention. The primary endpoint of the study was the proportion of moderate to severe anaemia in children aged 6-59 months. For assessment of the development of drug efficacy over time, an in vivo CQ efficacy study was nested into the trial. The study is registered under http://www.controlled-trials.com (ISRCTN 34104704).

RESULTS

The intervention was shown to be feasible under program conditions and a total of 1.076 children and 999 children were evaluated at baseline and follow-up time points respectively. Self-reported CQ treatment of fever episodes at home as well as referrals to health centres increased over the study period. At follow-up, CQ was detected in the blood of high proportions of intervention and control children. Compared to baseline findings, the prevalence of anaemia (29% vs 16%, p < 0.0001) and malaria parameters such as prevalence of P. falciparum parasitaemia, fever and palpable spleens was lower at follow-up but there were no differences between the intervention and control group. CQ efficacy decreased over the study period but this was not associated with the intervention.

DISCUSSION

The decreasing prevalence of malaria morbidity including anaemia over the study period can be explained by an overall increase of malaria prevention and treatment activities in the study area. The lack of effectiveness of the intervention was likely caused by contamination, pre-existing differences in the coverage of malaria treatment in both study groups and an unexpectedly rapid increase of resistance against CQ, the first-line treatment drug at the time of the study.

Calcium channel antagonist (nifedipine) attenuates Plasmodium berghei-specific T cell immune responses in Balb/C mice

Nifedipine and verapamil (Martin et al. Science 1987;235:899-901) are a class of calcium channel blockers involved in the reversal of chloroquine (CQ) drug resistance in CQ-sensitive Plasmodium spp. Nifedipine alters calcium-dependent functions of macrophages and neutrophils during Plasmodium berghei malaria. However, knowledge of nifedipine-induced immunomodulation of T cell functions during P. berghei malaria is still limited. We investigated the effect of nifedipine on the immune status of splenic T cells during P. berghei malaria. The intracellular calcium levels were determined in the FURA-2A/M loaded T cells by spectrofluorometry. Splenic T cell proliferation, phosphatidylserine (PS) externalization, Fas expression and Bcl2/Bax expression were determined by flow cytometry. We report a significant increase in mean percent parasitemia in nifedipine-treated and P. berghei-infected mice. Although nifedipine treatment alone did not affect the resting state free calcium levels in splenic T cells, the rise in intracellular calcium levels of T cells following P. berghei infection was significantly less in nifedipine-treated mice compared to untreated groups at various parasitemia levels. Antigen-specific splenic T cell proliferation and apoptosis was ablated in nifedipine-treated and untreated groups at various parasitemia levels. The study unequivocally reflects the suppression of P. berghei-specific T cell immune responses by nifedipine.

Abrogation of skin disease in LUPUS-prone MRL/FASlpr mice by means of a novel tylophorine analog

OBJECTIVE

To test the therapeutic effect of DCB-3503, a synthetic compound derived from a natural product that inhibits NF-kappaB, on end-organ disease in the MRL-Fas(lpr) murine model of systemic lupus erythematosus (SLE).

METHODS

Eight-week-old female MRL/Fas(lpr) mice were treated intraperitoneally with a low (2 mg/kg) or high (6 mg/kg) dose of DCB-3503 for 10 weeks. Control groups were administered vehicle treatment alone (negative control) or 25 mg/kg cyclophosphamide (positive control). Mice were bled before (8 weeks) and during (13 weeks) treatment, and when they were killed (20 weeks), and serum samples were analyzed for total IgM and IgG levels and autoantibody titers. When the mice were killed, spleen and lymph nodes (axillary, brachial, and cervical) were examined by flow cytometric analysis. The presence of skin and renal disease was determined by histopathologic analysis.

RESULTS

DCB-3503 reduced anti-double-stranded DNA and antichromatin autoantibodies and nearly abrogated inflammatory skin disease in MRL/Fas(lpr) mice; however, it had little effect on histologic kidney disease. Treated mice did not have hematologic or hepatic toxicity. These data indicate that end-organ disease in MRL/Fas(lpr) mice responds differentially to NF-kappaB inhibitor.

CONCLUSION

DCB-3503 causes significant abrogation of skin disease in MRL/Fas(lpr) mice and may potentially be beneficial in the treatment of inflammatory skin disease in SLE.

Inhibiting vascular endothelial growth factor receptor-2 signaling reduces tumor burden in the ApcMin/+ mouse model of early intestinal cancer

The Apc(Min/+) mouse model is a clinically relevant model of early intestinal cancer. We used AZD2171, an oral, highly potent and selective vascular endothelial growth factor (VEGF) signaling inhibitor, to investigate the role of VEGF receptor-2 (VEGFR-2) signaling in adenoma development and growth in Apc(Min/+) mice. AZD2171 (5 mg/kg body wt/day) was administered once daily for 28 days to 6-week-old (early-intervention) or 10-week-old (late intervention) mice. In the early-intervention study, AZD2171 reduced the number of macroscopic polyps in the small bowel and colon. Macropolyp diameter was lower in the small bowel, but remained unchanged in the colon. In animals receiving AZD2171, microscopic evaluation of the small intestine showed a significant reduction in the number of larger lesions. In the late-intervention study, AZD2171 treatment reduced macropolyp diameter (but not number) in the small intestine. Microscopic analysis revealed that AZD2171 significantly reduced the number of larger micropolyps in the small bowel, with no large micropolyps present in the colon. AZD2171 treatment had no effect on microvessel density or localization of beta-catenin staining in adenomas or non-tumor intestinal tissue, but significantly reduced the number of cells expressing VEGFR-2 mRNA. In conclusion, the effects of AZD2171 in the small intestine of Apc(Min/+) mice are consistent with an antiangiogenic mechanism of action, limiting growth of adenomas to < or =1 mm. These data also suggest that an early step in adenoma development may depend on VEGFR-2 signaling. Together, these results indicate that VEGFR-2 signaling may play key roles in the development and progression of intestinal adenomas.

Superior effects of high-dose enzyme replacement therapy in type 1 Gaucher disease on bone marrow involvement and chitotriosidase levels: a 2-center retrospective analysis

Dosing of enzyme replacement therapy (ERT) for Gaucher disease type 1 is still a subject of debate and varies from 15 to 130 U/kg/mo, making a huge economic difference of 70,000 US dollars to 380,000 US dollars(euro55,000-300,000) per patient per year. To investigate whether this difference in dosing ultimately translates into a different response, we retrospectively compared long-term outcome of ERT at 2 large European treatment centers, Academic Medical Center, Amsterdam, The Netherlands (n = 49, median dose, 15-30 U/kg/4 wks) and Heinrich-Heine University, Duesseldorf, Germany (n = 57, median dose, 80 U/kg/4 wks). These adult cohorts had a similar genetic background. All follow-up parameters were matched separately at baseline, to avoid bias with respect to disease severity. Improvement in hemoglobin, platelet count, and hepatosplenomegaly was not significantly different between both cohorts, whereas plasma chitotriosidase and bone marrow involvement by magnetic resonance imaging improved more quickly and was more pronounced in the higher-dosed group. Major bone complications rarely occurred in both groups. In conclusion, different dosing regimens of ERT do not affect outcome of hematologic and visceral parameters, but higher dosing leads to accelerated decrease of chitotriosidase and better objective bone response in adult type 1 Gaucher disease.

Regression of hepatosplenomegaly in Kenyan school-aged children after praziquantel treatment and three years of greatly reduced exposure to Schistosoma mansoni

Evaluating regression of morbidity associated with parasitic infections is an important component of community-based control programmes. We performed an intervention against Schistosoma mansoni infection, focusing on hepatosplenomegaly in the absence of periportal fibrosis, in a cohort of 67 Kenyan children aged 7-18 years from Makueni District, selected on the basis of hepatosplenomegaly detected by ultrasonography. Clinical and ultrasound examinations were conducted annually for three years after treatment, and the source of infection (a river) was regularly treated with molluscicide, thereby severely reducing exposure to schistosomiasis. Malaria transmission was uninterrupted. The prevalence of hard spleens, and the magnitude of clinically assessed splenomegaly along the mid-axillary and mid-clavicular lines decreased monotonically over time, independently of age, whereas clinically measured hepatomegaly along the mid-sternal line and the prevalence of firm livers decreased in an age-specific manner, being more pronounced amongst children aged 14 years or older at enrolment. Ultrasound data were less informative, and did not concur with clinical observations. These results demonstrate that praziquantel treatment reduces hepatosplenomegaly in the absence of exposure to S. mansoni, even with continuing exposure to malaria. The lack of complete resolution of hepatosplenomegaly in most children suggests, among other things, a residual organomegaly attributable to malaria.

Partial splenic embolization in patients with idiopathic portal hypertension

PURPOSE

To evaluate the effectiveness of partial splenic embolization (PSE) in patients with idiopathic portal hypertension (IPH) in reducing variceal bleeding episodes, splenomegaly and thrombocytopenia.

MATERIALS AND METHODS

Six patients (2M, 4F, mean age 30.3 years) with IPH presenting with splenomegaly, thrombocytopenia and recurrent variceal bleeding were treated with PSE using gelatin sponge (four patients) or Contour particles (two patients) as embolization material.

RESULTS

PSE was performed successfully in all cases; 3F coaxial microcatheters were necessary in two patients due to extreme splenic artery tortuosity. The average amount of devascularized parenchyma at CT 1 week after PSE was 71%. Splenomegaly and thrombocytopenia improved in all cases, with a mean platelet count increase of 120,000/mm(3) and an average 68% reduction of spleen volume at follow up. Variceal bleeding did not recur after PSE. Esophageal or gastroesophageal varices disappeared (one patient) or significantly reduced (five patients) at endoscopic controls. No significant complications were noted. The follow up was of at least 18 months in all patients; mean follow up was 28.2 months.

CONCLUSION

In patients with IPH PSE can be effective in preventing variceal bleedings, in reducing spleen volume and in significantly increasing platelet count; therapeutic results were durable in our population.

Negative role of colony-stimulating factor-1 in macrophage, T cell, and B cell mediated autoimmune disease in MRL-Fas(lpr) mice

Inflammation in the kidney and other tissues (lung, and salivary and lacrimal glands) is characteristic of MRL-Fas(lpr) mice with features of lupus. Macrophages (Mphi) are prominent in these tissues. Given that 1) Mphi survival, recruitment, proliferation, and activation during inflammation is dependent on CSF-1, 2) Mphi mediate renal resident cell apoptosis, and 3) CSF-1 is up-regulated in MRL-Fas(lpr) mice before, and during nephritis, we hypothesized that CSF-1-deficient MRL-Fas(lpr) mice would be protected from Mphi-mediated nephritis, and the systemic illness. To test this hypothesis, we compared CSF-1-deficient MRL-Fas(lpr) with wild-type strains. Renal pathology is suppressed and function improved in CSF-1-deficient MRL-Fas(lpr) mice. There are far fewer intrarenal Mphi and T cells in CSF-1-deficient MRL-Fas(lpr) vs wild-type kidneys. This leukocytic reduction results from suppressed infiltration, and intrarenal proliferation, but not enhanced apoptosis. The CSF-1-deficient MRL-Fas(lpr) kidneys remain preserved as indicated by greatly reduced indices of injury (nephritogenic cytokines, tubular apoptosis, and proliferation). The renal protective mechanism in CSF-1-deficient mice is not limited to reduced intrarenal leukocytes; circulating Igs and autoantibodies, and renal Ig deposits are decreased. This may result from enhanced B cell apoptosis and fewer B cells in CSF-1-deficient MRL-Fas(lpr) mice. Furthermore, the systemic illness including, skin, lung, and lacrimal and salivary glands pathology, lymphadenopathy, and splenomegaly are dramatically suppressed in CSF-1-deficient MRL-Fas(lpr) as compared with wild-type mice. These results indicate that CSF-1 is an attractive therapeutic target to combat Mphi-, T cell-, and B cell-mediated autoimmune lupus.

Transgenic Expression of CTLA-4 Controls Lymphoproliferation in IL-2-Deficient Mice

IL-2-deficient mice develop a lymphoproliferative and autoimmune disease characterized by autoimmune hemolytic anemia (AHA) and inflammatory bowel disease. We have previously reported that IL-2 is necessary for optimal up-regulation of CTLA-4, an inducible negative regulator of T cell activation. In this study, we have tested the hypothesis that reduced expression of CTLA-4 in IL-2-deficient T cells contributes to the pathogenesis of disease in IL-2-deficient mice. Expression of CTLA-4 as a transgene completely prevented lymphoaccumulation and AHA in IL-2-deficient mice. The normalization of T cell numbers was due to inhibition of expansion of conventional CD4+CD25- T cells rather than to rescue of the numbers or function of CD4+CD25+ regulatory T cells, suggesting that CTLA-4 expression on conventional T cells plays a role in maintaining normal T cell homeostasis. In addition, the inhibitory effect of the CTLA-4 transgene on T cell expansion was at least in part independent of CD28 expression. Our results suggest that deficient CTLA-4 expression on conventional T cells contributes to the pathophysiology of the lymphoproliferative disease and AHA in IL-2-deficient mice. Thus, restoring CTLA-4 expression in T cells may be an attractive strategy to control clinical autoimmune diseases in which CTLA-4 expression is reduced.

Low-dose thalidomide ameliorates cytopenias and splenomegaly in myelofibrosis with myeloid metaplasia: a phase II trial

PURPOSE

A phase II dose-escalation trial was conducted to ascertain low-dose thalidomide safety and response in patients with advanced myelofibrosis with myeloid metaplasia (MMM).

PATIENTS AND METHODS

Thalidomide was administered together with current therapy to 63 patients, starting at 50 mg daily and increasing to 400 mg as tolerated.

RESULTS

Half of the patients sustained daily doses more than 100 mg and the drop-out rate was 51% at 6 months: the drop-out rate was lower in patients with high baseline fatigue score. At efficacy analysis, anemia was ameliorated in 22% of the patients and transfusions were eliminated in 39% of transfusion-dependent patients. Platelet count increased by 50 x 10(9)/L or more in 22% of patients with an initial count lower than 100 x 10(9)/L. Splenomegaly decreased by more than 50% of the initial size in 19% of patients. Reduction of an overall disease severity score occurred in 31% of patients and was associated with a significant reduction of fatigue. Disease severity amelioration was independently predicted by a high baseline myeloproliferative index (ie, large splenomegaly, thrombocytosis, or leukocytosis).

CONCLUSION

Low-dose thalidomide displays an acceptable toxicity profile and provides an objective and subjective advantage to a relevant portion of MMM patients.

Retinoic acid reduces autoimmune renal injury and increases survival in NZB/W F1 mice

Retinoic acids, a group of natural and synthetic vitamin A derivatives, have potent antiproliferative and anti-inflammatory properties. Recently, retinoic acids were reported to inhibit Th1 cytokine production. We investigated the effects of retinoic acid on lupus nephritis in a model of NZB/NZW F(1) (NZB/W F(1)) mice. Three-month-old NZB/W F(1) mice were separated into two groups: one treated with all-trans-retinoic acid (ATRA; 0.5 mg i.p., three times weekly for 7 mo) and one with saline as a control. Compared with controls, ATRA-treated mice survived longer and exhibited a significant reduction of proteinuria, renal pathological findings including glomerular IgG deposits, and serum anti-DNA Abs. Splenomegaly was less marked in the treated mice than in controls. Transcripts encoding IFN-gamma, IL-2, and IL-10 in splenic CD4(+) T cells were significantly reduced in treated mice compared with controls. We conclude that treatment with ATRA in SLE-prone NZB/W F(1) mice significantly alleviates autoimmune renal disorder and prolongs survival; this may thus represent a novel approach to the treatment of patients with lupus nephritis.

Myeloablation and autologous peripheral blood stem cell rescue results in hematologic and clinical responses in patients with myeloid metaplasia with myelofibrosis

Current therapeutic options for myeloid metaplasia with myelofibrosis (MMM) are limited. A pilot study was conducted of autologous peripheral blood stem cell (PBSC) collection in 27, followed by transplantation in 21 patients with MMM. The median age was 59 (range 45-75) years. PBSCs were mobilized at steady state (n = 2), after granulocyte colony-stimulating factor (G-CSF) alone (n = 17), or after anthracycline-cytarabine induction plus G-CSF (n = 8). A median of 11.6 x 10(6) (range 0 to 410 x 10(6)) CD34(+) cells per kilogram were collected. Twenty-one patients then underwent myeloablation with oral busulfan (16 mg/kg) and PBSC transplantation. The median times to neutrophil and platelet recovery after transplantation were 21 (range 10-96) and 21 (range, 13 to > or = 246) days, respectively. Five patients received back-up PBSC infusion because of delayed neutrophil or platelet recovery. The median follow-up is 390 (range 70-1623) days after transplantation, and the 2-year actuarial survival is 61%. After transplantion, 6 patients died: 3 of nonrelapse causes (1 within 100 days of PBSC infusion) and 3 of disease progression. Erythroid response (hemoglobin > or = 100 g/L [10 gm/dL] without transfusion for > or = 8 weeks) occurred in 10 of 17 anemic patients. Four of 8 patients with a platelet count less than 100 x 10(9)/L (100 000/microL) responded with a durable platelet count more than 100 x 10(9)/L (100 000/microL). Symptomatic splenomegaly improved in 7 of 10 patients. It is concluded that (1) PBSC collection was feasible and stable engraftment occurred after transplantation in most patients with MMM, (2) myeloablation with busulfan was associated with acceptable toxicity, (3) a significant proportion of patients derived clinical benefit after treatment, and (4) further investigation of this novel approach is warranted. (Blood. 2001;98:586-593)

Impaired mucosal immunity in L-selectin-deficient mice orally immunized with a Salmonella vaccine vector

Lymphocyte trafficking in the gastrointestinal tract is primarily mediated by interactions with the mucosal addressin cell adhesion molecule 1 and its lymphocyte ligand, alpha(4)beta(7), and partly by L-selectin (L-Sel) interactions with peripheral node addressin coexpressed on some mucosal addressin cell adhesion molecule 1. We inquired whether intestinal responses in mice lacking L-Sel would be enhanced. L-Sel-deficient (L-Sel(-/-)) mice were orally immunized with either Salmonella vaccine vector or Salmonella vector-expressing colonization factor Ag I (CFA/I) from enterotoxigenic Escherichia coli. In L-Sel(-/-) mice, mucosal IgA anti-CFA/I fimbrial responses were greatly reduced, and systemic IgG2a anti-CFA/I fimbrial responses were 26-fold greater compared with C57BL/6 (L-Sel(+/+)) mice. L-Sel(-/-) Peyer's patch (PP) CD4(+) Th cells revealed IFN-gamma-dominated responses and an unprecedented absence of IL-4, whereas the expected mixed Th cell phenotype developed in L-Sel(+/+) mice. PP CD4(+) Th cell anti-Salmonella responses were nearly nonexistent in L-Sel(-/-) mice immunized with either Salmonella vaccine. Splenic CD4(+) Th cell anti-Salmonella responses were reduced but did show cytokine production in Ag restimulation assays. Increased colonization of PP and spleen was noted only with the Salmonella vector in L-Sel(-/-) mice, resulting in increased splenomegaly, suggesting that the Salmonella-CFA/I vaccine was not as infectious or that the presence of the fimbriae improved clearance, possibly because of reduced neutrophil recruitment. However, sufficient anti-Salmonella immunity was induced, because Salmonella vector-immunized L-Sel(-/-) mice showed complete protection against wild-type Salmonella challenge, unlike L-Sel(+/+) mice. This evidence shows that L-Sel is important for development of mucosal immunity, and absence of L-Sel is protective against salmonellosis.

Five years of experience with hydroxyurea in children and young adults with sickle cell disease

The short-term beneficial effect of hydroxyurea (HU) in sickle cell disease (SCD) has been proven by randomized studies in children and adults. The Belgian registry of HU-treated SCD patients was created to evaluate its long-term efficacy and toxicity. The median follow-up of the 93 patients registered is 3.5 years; clinical and laboratory data have been obtained for 82 patients at 1 year, 61 at 2 years, 44 at 3 years, 33 at 4 years, and 22 after 5 years. On HU, the number of hospitalizations and days hospitalized dropped significantly. Analysis of the 22 patients with a minimum of 5 years of follow-up confirm a significant difference in the number of hospitalizations (P =.0002) and days in the hospital (P <.01), throughout the treatment when compared to prior to HU therapy. The probabilities of not experiencing any event or any vaso-occlusive crisis requiring hospitalization during the 5 years of treatment were, respectively, 47% and 55%. On HU, the rate per 100 patient-years of severe events was estimated to be 3.5% for acute chest syndrome, 1.2% for aplastic crisis, 0.4% for splenic sequestration; it was 0% for the 9 patients with a history of stroke or transient ischemic attack followed for an average of 4 years. No important adverse effect occurred. Long-term chronic treatment with HU for patients with SCD appears feasible, effective, and devoid of any major toxicity; in patients with a history of stroke, HU may be a valid alternative to chronic transfusion support. (Blood. 2001;97:3628-3632)

Biochemical effects of vinyl chloride monomer on the liver of occupationally exposed workers

We investigated the effects of vinyl chloride monomer exposure on the liver of 86 workers by measuring beta-glucuronidase, arylsulfatase A, adenosine deaminase, 5'-nucleotidase and routine liver function enzymes in the sera of the workers. In 21 of them, three or more of these parameters were raised, with a significant decrease in the level of blood glutathione and a significant increase in the enzyme activity level of glutathione S-transferase. Of these 21 workers, 14 had fatty liver infiltration, 8 of whom were also suffering from liver enlargement. Also, 4 workers had liver enlargement without fatty infiltration and 3 had enlarged spleens. The study highlights the need for vigilance in environmental monitoring and medical surveillance of workers exposed to this chemical.

Different immunological requirements for protection against acute versus persistent Friend retrovirus infections

The propensity of retroviruses to rapidly establish persistent infections poses a formidable problem in vaccination strategies. In the current study, we use a live attenuated vaccine to study protection against acute and persistent Friend virus infections in mice. Adoptive transfers of immune CD8(+) T cells combined with passive immunizations with virus-neutralizing antibodies increased protection against acute disease compared with either treatment alone, but there was no protection against the establishment of persistent infection. In addition, the protection against acute disease elicited by the combination treatment was dependent on endogenous CD4(+) T cells as no protection was achieved in CD4(+) T-cell-depleted mice. Quantitative studies showed that doubling the numbers of immune lymphocytes used in adoptive transfer experiments increased protection against acute disease depending on the type of lymphocyte subset used in the transfer. CD8(+) T cells were the most potent subset for the transfer of such protection. However, even high numbers of immune CD8(+) T cells gave no protection against the establishment of persistent infections. The data indicate that strengthening the numbers of specific immune cell subsets may have a beneficial effect on protection against acute disease, but protection from establishment of persistence requires complex immune responses involving multiple lymphocyte subsets.

Delayed immune aging in diet-restricted B6CBAT6 F1 mice is associated with preservation of naive T cells

Age-related changes in peripheral blood, spleen, and thymus of ad libitum (AL)-fed and dietary restricted (DR) C57BL/6J x CBA/CaH-T6/J F1 (B6CBAT6 F1) mice at young (3 mo), middle (16 mo), and old (30 mo) ages were studied to define how dietary restriction retards immune aging. Dietary restriction at 25% AL intake level initiated at weaning significantly reduced the rates of age-related declines in peripheral blood T helper cells, naive T helper cells, and naive cytotoxic T lymphocytes (CTLs). As a result, concentrations of these cell types in old DR mice were equivalent to 161%, 176%, and 250% of those in old AL controls. Dietary restriction also abolished age-related splenomegaly and decreased total splenocyte numbers in old DR mice. Dietary restriction did not prevent age-related decline in thymus size, but preserved thymus cellularity in old mice. Old DR mice had twice as many total thymocytes and 2.6 times as many CD4+CD8+ immature thymocytes as old AL controls. The correlations between total immature thymocytes and concentrations of circulating naive T helper cells and naive CTLs increase with age and become significant in old mice. Thus, dietary restriction preserves immature T-cell precursors in the thymus during aging to maintain higher concentrations of circulating T helper and naive T cells in peripheral blood.

IFN-gamma receptor signaling is essential for the initiation, acceleration, and destruction of autoimmune kidney disease in MRL-Fas(lpr) mice

CSF-1 and TNF-alpha in the kidney of MRL-Fas(lpr) mice are proximal events that precede and promote autoimmune lupus nephritis, while apoptosis of renal parenchymal cells is a feature of advanced human lupus nephritis. In the MRL-Fas(lpr) kidney, infiltrating T cells that secrete IFN-gamma are a hallmark of disease. To examine the impact of IFN-gamma on renal injury in MRL-Fas(lpr) mice, we constructed a IFN-gamma R-deficient strain. In MRL-Fas(lpr) mice lacking IFN-gamma R, circulating and intrarenal CSF-1 were absent, TNF-alpha was markedly reduced, survival was extended, lymphadenopathy and splenomegaly were prevented, and the kidneys remained protected from destruction. Mesangial cells (MC) that were signaled through the IFN-gamma R induced CSF-1 and TNF-alpha in MRL-Fas(lpr) mice. We detected a large number of apoptotic renal parenchymal cells in advanced nephritis and determined that signaling via the IFN-gamma R induces apoptosis of tubular epithelial cells (TEC), but not MC. By comparison, TNF-alpha induces apoptosis in MC, but not TEC, of the MRL-Fas(lpr) strain. Thus, IFN-gamma is directly and indirectly responsible for apoptosis of TEC and MC in MRL-Fas(lpr) mice, respectively. In conclusion, IFN-gamma R signaling is essential for the initiation (CSF-1), acceleration (CSF-1 and TNF-alpha), and apoptotic destruction of renal parenchymal cells in MRL-Fas(lpr) autoimmune kidney disease.

N-acetyl penicillamine a protector of Plasmodium berghei induced stress organ injury in mice

N-acetyl penicillamine (NAP), a derivative of penicillamine and copper chelator has been employed as a potential protector of host stress organ injury during Plasmodium berghei infection in mice. Intramuscular injection of NAP (60 mg kg-1 body wt for 10 days) to P. berghei mice was able to restrict the hepato- and splenomegaly. The mortality rate of infected mice was decreased by 50% by NAP. The decreased protein and lipid peroxidation and increased copper contents during P. berghei were almost normalized after NAP treatment. The increased levels of erythrocytic superoxide anion and lipid peroxides due to infection were almost normalized after NAP treatment.

Prevention of splenic granuloma formation in adjuvant arthritis by 2-acetyl-4-tetrahydroxybutylimidazole (THI)

Adjuvant-induced arthritis (AA) in Lewis rats is a widely used model of chronic inflammatory arthritis. Non-articular features such as weight loss and necrotizing granulomas of the spleen and lymph nodes also occur in this model. The compound 2-acetyl-4-tetrahydroxybutylimidazole (THI) marginally delayed the development of AA. However, this agent had no effect on the incidence or severity of disease. In contrast, THI totally prevented granuloma formation in the spleen and associated splenomegaly. We conclude that THI may be a useful adjunctive agent for some inflammatory diseases.

Maloprim malaria prophylaxis in children living in a holoendemic village in north-eastern Tanzania

A randomized, double-'blind', placebo-controlled trial of weekly Maloprim (dapsone-pyrimethamine, D-P) for malaria prophylaxis was conducted at Magoda village in north-eastern Tanzania. The effect of D-P on the incidence of clinical malaria, Plasmodium falciparum prevalence and density, splenomegaly, and packed cell volume (PCV) was investigated in a cohort of 249 children (126 receiving D-P and 123 receiving placebo) aged 1-9 years. The case definition of clinical malaria (malaria fever) was measured axillary temperature > or = 37.5 degrees C and/or reported fever, and P. falciparum asexual parasitaemia > or = 5000/microL. Children aged 1-4 years given D-P experienced 1.56 episodes of clinical malaria per year, whereas children on placebo experienced 2.55 episodes (relative rate [RR] = 0.61, 95% confidence interval [CI] 0.47, 0.80). Thus, D-P protective efficacy against clinical malaria, in this age group, was 39% (95% CI 20%, 53%; P = 0.0002). The annual incidence of clinical malaria among children aged 5-9 years was 0.16 episodes in the D-P group and 0.26 episodes in those receiving placebo (RR = 0.58, 95% CI 0.26, 1.28; P = 0.17). Increased malaria transmission and drug resistance, during the course of the trial, resulted in a reduction in the protective efficacy of D-P. Overall, D-P was able to reduce parasite densities and splenomegaly. D-P prophylaxis also resulted in an increase in PCV but this effect diminished towards the end of the trial. D-P exerted a suppressive effect on asexual parasitaemia throughout the trial.

Antibody to the ligand for CD40 (gp39) inhibits murine AIDS-associated splenomegaly, hypergammaglobulinemia, and immunodeficiency in disease-susceptible C57BL/6 mice

Infection of genetically susceptible C57BL/6 mice with the LP-BM5 isolate of murine retroviruses cause profound splenomegaly, hypergammaglobulinemia, lymphadenopathy, and an immunodeficiency syndrome which includes the development of terminal B-cell lymphomas. Because many of these and the other manifestations of LP-BM5 virus-induced disease are similar to those seen in AIDS, this syndrome has been named murine AIDS, or MAIDS. Previous reports have shown that the onset of MAIDS depends on the presence of both CD4+ T cells and B cells and have suggested that CD4+ T-cell-B-cell interactions are important to disease pathogenesis. Here, we assessed the possibility that interactions between CD40 and its ligand on activated CD4+ T cells, CD40 ligand/gp39, are involved in the development of MAIDS. To test this hypothesis, LP-BM5-infected B6 mice were treated in vivo with anti-gp39 monoclonal antibody. As a result, MAIDS-associated splenomegaly, hypergammaglobulinemia, germinal center formation, and the loss of in vitro responsiveness to the T- and B-cell mitogens concanavalin A and lipopolysaccharide were inhibited. Anti-gp39 monoclonal antibody-treated LP-BM5-infected mice were also able to mount essentially normal alloantigen-specific cytolytic T-lymphocyte responses. These results support the possibility that molecular interactions between CD40 and gp39 are critical to the development of MAIDS.

The effect of indomethacin administration on the splenic changes induced by estradiol supplementation in ovariectomized New Zealand white rabbits

In an effort to elucidate the mechanism by which indomethacin (IN) lessens the stimulatory effect of estradiol (E2) on rabbit splenic red pulp macrophages (RPMs), 39 female New Zealand White rabbits were divided into 10 groups: ovariectomized (OVX) and OVX/IN at 0.1 and 5.0 mg/kg body weight (bw)/day; sham OVX (SOVX) and SOVX/IN at 0.1 and 5.0 mg/kg bw/day; OVX/25 mg E2 and OVX/25 mg E2/IN at 0.1 and 5.0 mg/kg bw/day; and intact control. Changes in RPM population in response to treatment were measured using a 0-4 histologic grade. Estradiol treatment resulted in increased RPM grade when compared to the OVX groups. Indomethacin addition lowered mean RPM grade in the SOVX/IN 5.0 group when compared to its E2 control group. Indomethacin administration had no significant effect on levels of prostaglandin E2 in spleen, urine, or blood. Hematocrits were reduced in both OVX and OVX/E2 groups; this decrease was exacerbated by the high IN dose. In summary, the results from this study suggest that the effect of IN on E2-induced RPM activation may be mediated through a nonprostaglandin pathway. The observed hematocrit changes are possibly the result of direct action of IN and E2 on erythrocytes, resulting in their accelerated clearance from the circulation by splenic RPM.

A comparison of the efficacy of insecticide-treated and untreated bed nets in preventing malaria in Gambian children

An evaluation of the Gambian national insecticide bed net programme, which has introduced insecticide treatment of bed nets into all primary health care (PHC) villages in The Gambia, provided an opportunity to compare the individual risk of malaria in children who slept under untreated or insecticide-treated bed nets. 2300 children 1-4 years old were selected for a survey at the end of the 1992 rainy season, 1500 from PHC villages and 800 from non-PHC villages. All malariometric indices were lower, and the mean packed cell volume was higher, in children who slept regularly under treated or untreated bed nets than in those who did not use a net. This study suggested that untreated bed nets provide some individual protection against malaria, although not as efficiently as that provided by insecticide-treated bed nets which were particularly effective at preventing infections accompanied by high parasitaemia.

FK506: therapeutic effects on lupus dermatoses in autoimmune-prone MRL/Mp-lpr/lpr mice

The effects of FK506, a new immunosuppressive agent, on the development of lupus dermatoses were investigated in the autoimmune-prone MRL/Mp-lpr/lpr (MRL/lpr) mouse, which is an animal model for the spontaneous development of skin lesions similar to those of human lupus erythematosus (LE). FK506 reduced the incidence of skin lesions, lupus nephritis, the titre of serum anti-double-stranded DNA antibodies and the massive T cell proliferation. The incidence and magnitude of IgG deposition at the dermoepidermal junction were not changed. These results suggest that FK506 is a promising immunosuppressive agent for the control of autoimmune skin diseases.

Inhibitory effects of recombinant human interleukin 10 on disease manifestations in a P-->F1 model of acute graft versus host disease

Interleukin 10 (IL-10) is a cytokine with both antiinflammatory and immunosuppressive properties. In the present study, we have examined the effects of recombinant human IL-10 (rHuIL-10) on the development of acute graft-vs.-host disease (GVHD) in unirradiated (C57B1/6JxA/J) F1 recipients of parental A/J lymphocytes. rHuIL-10 (2.5 to 100 micrograms/mouse administered subcutaneously) caused a significant reduction in splenomegaly in GVH mice. GVH splenocytes exhibited an augmented capacity to produce IFN-gamma when stimulated in culture with Con A or LPS. The IFN gamma produced in response to LPS stimulation was found to be derived from CD4+ and CD8+ T cells with little or no contribution from the NK1.1+ subpopulation of the GVH spleen. Treatment with IL-10 in vivo was found to diminish the capacity of splenocytes to produce IFN gamma when stimulated with LPS but not with Con A. IL-10 did not protect GVH mice from a lethal dose of LPS but caused a marked reduction in the serum TNF alpha response triggered by the LPS challenge. We conclude that IL-10 may be useful in controlling those clinical manifestations of acute GVHD that arise as a result of the activities of proinflammatory cytokines such as IFN gamma and TNF alpha.

The effect of cyclosporin A, FK506, and rapamycin on the murine chronic graft-versus-host response--an in vivo model of Th2-like activity

We have evaluated the effects of three potent immunosuppressive agents: cyclosporin A, FK506, and rapamycin, on a murine chronic graft-versus-host response (chronic GVHR). The chronic GVHR has previously been described to be a Th2-like response, and is characterized by a marked splenomegaly and hyper-IgE production in the early stages of the response. The effects of the immunosuppressive agents on both splenomegaly and hyper-IgE were measured 3 weeks after the induction of the chronic GVHR. Rapamycin was found to inhibit both splenomegaly and the hyper-IgE response in a dose-dependent manner. Unexpectedly cyclosporin A and FK506 were found to potentiate markedly both the splenomegaly and hyper-IgE response at low doses before exhibiting an inhibitory effect at higher doses. We propose the differences of activity seen with rapamycin compared with cyclosporin A and FK506 may be explained by their different mechanisms of action, and also by the selectivity of low dose cyclosporin A and FK506 for Th1-like lymphocytes. The implications of these observations are discussed in relation to the use of these immunosuppressives for the treatment of Th2-like diseases.

In vivo treatment with interleukin 12 protects mice from immune abnormalities observed during murine acquired immunodeficiency syndrome (MAIDS)

Lymphoproliferation, chronic B cell activation resulting in hypergammaglobulinemia, and profound immunodeficiency are prominent features of a retrovirus-induced syndrome designated murine acquired immunodeficiency syndrome (MAIDS). In vivo treatment of infected mice with recombinant interleukin 12 (IL-12) beginning at the time of infection or up to 9 wk after virus inoculation markedly inhibited the development of splenomegaly and lymphadenopathy, as well as B cell activation and Ig secretion. Treatment with IL-12 also had major effects in preventing induction of several immune defects including impaired production of interferon gamma (IFN-gamma) and IL-2 and depressed proliferative responses to various stimuli. The therapeutic effects of IL-12 on the immune system of mice with MAIDS were also associated with reduced expression of the retrovirus that causes this disease (BM5def), with lesser effects on expression of ecotropic MuLV. IL-12 treatment was not effective in IFN-gamma knockout mice or in infected mice treated simultaneously with IL-12 and anti-IFN-gamma. These results demonstrate that induction and progression of MAIDS are antagonized by IL-12 through high-level expression of IFN-gamma and may provide an experimental basis for developing treatments of retrovirus-induced immune disorders with similar immunopathogenic mechanisms.

Antiproliferative effect of D-aspartic acid beta-hydroxamate (DAH) on Friend virus-infected erythropoietic progenitor cells

D-aspartic beta-hydroxamate (DAH), an aspartic acid analog, exerts antitumoral activity on murine leukemia L5178Y, both in vitro and in vivo. In this study, we show that DAH is also active in vivo against Friend virus (FV-P)-induced erythroleukemia, and we report the effects of DAH in vivo an in vitro on FV-P target cells, i.e. the mature erythroid colony-forming cells (CFU-E). DAH treatment (2 g/kg/day) given for 95 days as a single daily i.p. injection to DBA/2 mice either 3 or 12 days following inoculation with a high dose (10(3) plaque-forming units) of FV-P resulted in a marked increase in the mean survival time of treated animals (212 and 191%, respectively). Since FV-P elicits spleen enlargement and polycythemia, we examined the effects of DAH on spleen size, spleen-nucleated cell number, and hematocrit, in normal and FV-P infected mice, at different times in the course of continuous DAH treatments. DAH treatment initiated 3 days after viral infection inhibits the virus-induced splenomegaly, with at day 26 p.i. 1.15 x 10(8) and 12.6 x 10(8) nucleated cells per spleen observed in DAH-treated mice and untreated mice respectively, whereas only 1.03 x 10(8) nucleated cells were observed in uninfected mice. Furthermore, DAH prevents virus-induced polycythemia: on day 26, an hematocrit of 39% was measured in DAH-treated mice as compared to 60% in untreated mice. DAH treatment initiated 12 days after viral infection reduces splenomegaly, the number of nucleated spleen cells and the hematocrit of infected mice. DAH treatment initiated 3 days after viral infection prevents the tremendous increase of CFU-E in the spleen of infected mice: on day 11, the spleen of infected mice contained 4.6 x 10(6) CFU-E, while the spleen of treated mice only contained 26 x 10(3) CFU-E, and on day 26 the spleen CFU-E numbers were 45.4 x 10(6) and 1.5 x 10(6) in untreated and treated infected mice, respectively. In control uninfected mice, DAH treatment induced a transient decrease in spleen CFU-E followed by a rebound phenomenon. In vitro, preincubation with DAH inhibits colony formation by FV-P infected CFU-E, at doses starting at 3 mM, as compared to uninfected CFU-E. These data show that DAH inhibits the expression of the retroviral infection, and appears to preferentially inhibit the proliferation of infected target cells (CFU-E) in vivo.

Reduction of HIV-1 antigen production by phosphatidylcholine containing formulations via growth inhibition of HIV-1-infected cells

Phosphatidylcholine (PC) and licensed formulations containing PC were tested for their influence on the proliferation and viability of cells permanently infected with HIV-1 (human immunodeficiency virus type 1). PC alone, as well as pharmaceutical formulations containing PC, selectively inhibited the growth of productively infected lymphoid cells. The strongest growth inhibition was observed with formulations containing PC, glycerol and triglyceride together. The growth inhibition was dose-dependent for HIV-1-infected cells. Additionally, PC-containing formulations dramatically reduced antigen production from peripheral blood mononuclear cells (PBMCs) infected in vitro with HIV-1. In vivo experiments with Rauscher-MuLV-infected mice showed that PC administered either intraperitoneally or orally was able to inhibit Rauscher-virus-induced splenomegaly. PC-containing formulations are currently used in man for supportive therapy at doses, which in vitro induced 50% growth inhibition of HIV-1-infected cells in vitro. Such doses have been used in man without side effects for many years. Thus, PC-containing formulations may be valuable for the treatment of HIV-1-infected individuals.

Treatment effect of a traditional Chinese medicine, ren-shen-yang-rong-tang (Japanese name: ninjin-youei-to), on autoimmune MRL/MP-lpr/lpr mice

MRL/Mp-lpr/lpr (MRL/lpr) mice were treated with a traditional Chinese herbal medicine, Ren-shen-yang-rong-tang (Japanese name: Ninjin-youei-to, NYT) intraperitoneally (i.p.) every 3 days or per os (p.o.) 6 times/week from before the onset of autoimmune disease (6 weeks of age). Fifty percent survival time was found in placebo-controlled male and female mice of 28 and 22 weeks of age, respectively. NYT-treatment markedly prolonged the survival time of MRL/lpr mice. That is, 50% survival time was 43 weeks in the i.p.-treated male mice and 30 weeks of age in the p.o.-treated female mice. Further, NYT-treatment significantly reduced occurrence of thymic atrophy and prevented the anomalous accumulation of B220+ T-cells in lymph node and spleen, both of which are characteristic in MRL/lpr mice. Moreover, grades of proteinuria were significantly reduced in both the i.p.- and p.o.-treated groups compared with the control groups. Such clinical benefit and increased survival time were interestingly not associated with the decrease in the level of autoantibodies.

Immunoregulation of SLE-like disease by the IL-1 receptor: disease modifying activity on BDF1 hybrid mice and MRL autoimmune mice

Due to the immunopharmacological profile of the recombinant IL-1 receptor (IL-1-R) and its potential to modulate biological activity in various inflammatory autoimmune disease models, we further elucidated its disease modifying activity on the development of a systemic lupus erythematosus (SLE)-like disease in BDF1 hybrid mice and in MRL/lpr autoimmune mice. Treatment of BDF1 mice with the IL-1-R during the induction phase resulted in a strong inhibition of the development of a glomerulonephritis, prolonged the survival time and improved the survival rate. Even a therapeutic effect was demonstrated when this receptor was given after the appearance of clinical symptoms. Treating MRL/lpr mice, which develop spontaneously a SLE-like disease, with the IL-1-R resulted in an inhibition of the developing glomerulonephritis and splenomegaly, in a reduction of swollen lymph nodes and in a decrease of autoantibody formation. Even in the established autoimmune disease of MRL/1 pr mice the IL-1-R reduced proteinuria, the levels of autoantibodies and also improved the survival rate.

Diethylcarbamazine in the control of splenomegaly associated with Bancroftian filariasis in the Ok Tedi area of Papua New Guinea

Bancroftian filariasis is highly endemic in the Ok Tedi region of Papua New Guinea, with a reported mean rate of 39% before the implementation of a single-dose diethylcarbamazine (DEC) treatment programme in 1986. This was followed by a 72% decline in the rate of detectable microfilaraemia and a 40% reduction in pre- and post-treatment splenomegaly. No significant difference was observed when spleen enlargement was compared to the presence of patent malaria. A significant difference in splenomegaly was observed between DEC-treated villagers and their untreated counterparts. Significant differences were reported in the rate of detectable microfilariae of Wuchereria bancrofti, but not of malaria, between the two groups. The number of DEC administrations and the period of time since the first treatment played a significant role immunologically. Significant differences were observed in immunoglobulin (Ig) M and IgG levels and in the extent of splenomegaly between DEC-treated and untreated areas. Filarial infection associated with malaria resulted in higher spleen rates and size. W. bancrofti is a major contributor to splenomegaly in the Ok Tedi region, and splenomegaly associated with bancroftian filariasis can be reduced or controlled by low, well-spaced doses of DEC.

Pharmacologic manipulation of graft versus host induced splenomegaly

A murine graft versus host (GVH) model was developed as a tool for drug discovery. A pharmacological survey revealed that as a class the anti-rheumatics (e.g., auranofin, azathioprine, and methotrexate) were the most potent inhibitors of GVH induced splenomegaly. The immunosuppressants, cyclophosphamide and cyclosporine A, and the glucocorticoids (e.g., dexamethasone, hydrocortisone, and corticosterone) were all able to suppress the GVH response. Anti-inflammatory agents (e.g., indomethacin and piroxicam), and a series of central nervous system affecting drugs, including serotonin agonists (e.g., trifluromethylphenylpiperazine (tfMPP), 1-(3-chlorophenyl)piperazine (mCPP), and quipazine), and tricyclic antidepressants (e.g., amitriptyline, desipramine, imipramine, and nortriptyline) typically were ineffective at doses up to 10 mg/kg. However, at high dose levels (30 mg/kg) piroxicam enhanced while amitriptyline and cyproheptadine (a mixed serotonin and histamine antagonist) suppressed GVH induced splenomegaly. These data provide a pharmacological profile for a series of immunomodulator, anti-inflammatory, and central nervous system active compounds in a classic immunologic model.