Megavoltage radiotherapy effects on organs of the reticuloendothelial system.

PURPOSE: To study the uptake capacity of cells from the reticuloendothelial system after irradiation with high-energy X-rays. METHODS: Eighteen male Wistar rats were distributed in three groups: group A (n = 6): control, unirradiated animals studied alongside animals from group B; group B (n = 6) and group C (n = 6): animals irradiated and studied after 24 and 48 hours, respectively. The rats were anesthetized and placed on a 10 MV linear accelerator. Next, they were irradiated in the abdominal region, with 8 Gy. Twenty-four (groups A and B) and 48 hours later (group C), a colloidal carbon solution (1 mL/kg) was intravenously injected in the tail vein. Fifty minutes later, the spleens and livers were withdrawn and prepared to be studied. Kupffer cells and splenic macrophages containing carbon pigments were counted in an optical microscope. Arithmetic means were calculated for each group and compared among them. RESULTS: X-rays were associated with a reduced number of Kupffer cells containing colloidal carbon, proliferation and enlargement of biliary ducts, hypoplasia, and hepatocyte necrosis. In the irradiated spleen, the colloidal carbon uptake was concentrated in the marginal zone around the white pulp, with an inexpressive uptake of pigments by macrophages from white and red pulps. CONCLUSIONS: The X-rays in the rat abdomen are associated with a reduction in the Kupffer cells uptake of colloidal carbon, hepatocyte disorders, bile duct proliferation, and splenic uptake of colloidal carbon concentrated in the marginal zone.

Peyer's patch phagocytes acquire specific transcriptional programs that influence their maturation and activation profiles.

Peyer's patches (PPs) are secondary lymphoid organs in contact with the external environment via the intestinal lumen, thus combining antigen sampling and immune response initiation sites. Therefore, they provide a unique opportunity to study the entire process of phagocyte differentiation and activation in vivo. Here, we deciphered the transcriptional and spatial landscape of PP phagocyte populations from their emergence in the tissue to their final maturation state at homeostasis and under stimulation. Activation of monocyte-derived Lysozyme-expressing dendritic cells (LysoDCs) differs from that of macrophages by their upregulation of conventional DC (cDC) signature genes such as Ccr7 and downregulation of typical monocyte-derived cell genes such as Cx3cr1. We identified gene sets that distinguish PP cDCs from the villus ones and from LysoDCs. We also identified key immature, early, intermediate, and late maturation markers of PP phagocytes. Finally, exploiting the ability of the PP interfollicular region to host both villous and subepithelial dome emigrated cDCs, we showed that the type of stimulus, the subset, but also the initial location of cDCs shape their activation profile and thus direct the immune response. Our study highlights the importance of targeting the right phagocyte subset at the right place and time to manipulate the immune response.

Megavoltage radiotherapy effects on organs of the reticuloendothelial system

Purpose: To study the uptake capacity of cells from the reticuloendothelial system after irradiation with high-energy X-rays. Methods: Eighteen male Wistar rats were distributed in three groups: group A (n = 6): control, unirradiated animals studied alongside animals from group B; group B (n = 6) and group C (n = 6): animals irradiated and studied after 24 and 48 hours, respectively. The rats were anesthetized and placed on a 10 MV linear accelerator. Next, they were irradiated in the abdominal region, with 8 Gy. Twenty-four (groups A and B) and 48 hours later (group C), a colloidal carbon solution (1 mL/kg) was intravenously injected in the tail vein. Fifty minutes later, the spleens and livers were withdrawn and prepared to be studied. Kupffer cells and splenic macrophages containing carbon pigments were counted in an optical microscope. Arithmetic means were calculated for each group and compared among them. Results: X-rays were associated with a reduced number of Kupffer cells containing colloidal carbon, proliferation and enlargement of biliary ducts, hypoplasia, and hepatocyte necrosis. In the irradiated spleen, the colloidal carbon uptake was concentrated in the marginal zone around the white pulp, with an inexpressive uptake of pigments by macrophages from white and red pulps. Conclusions: The X-rays in the rat abdomen are associated with a reduction in the Kupffer cells uptake of colloidal carbon, hepatocyte disorders, bile duct proliferation, and splenic uptake of colloidal carbon concentrated in the marginal zone.

Camouflage strategies for therapeutic exosomes evasion from phagocytosis.

Background: Even though exosome-based therapy has been shown to be able to control the progression of different pathologies, the data revealed by pharmacokinetic studies warn of the low residence time of exogenous exosomes in circulation that can hinder the clinical translation of therapeutic exosomes. The macrophages related to the organs of the mononuclear phagocytic system are responsible primarily for the rapid clearance and retention of exosomes, which strongly limits the amount of exosomal particles available to reach the target tissue, accumulate in it and release with high efficiency its therapeutic cargo in acceptor target cells to exert the desired biological effect. Aim of review: Endowing exosomes with surface modifications to evade the immune system is a plausible strategy to contribute to the suppression of exosomal clearance and increase the efficiency of their targeted content delivery. Here, we summarize the current evidence about the mechanisms underlying the recognition and sequestration of therapeutic exosomes by phagocytic cells. Also, we propose different strategies to generate 'invisible' exosomes for the immune system, through the incorporation of different anti-phagocytic molecules on the exosomes' surface that allow increasing the circulating half-life of therapeutic exosomes with the purpose to increase their bioavailability to reach the target tissue, transfer their therapeutic molecular cargo and improve their efficacy profile. Key scientific concepts of review: Macrophage-mediated phagocytosis are the main responsible behind the short half-life in circulation of systemically injected exosomes, hindering their therapeutic effect. Exosomes 'Camouflage Cloak' strategy using antiphagocytic molecules can contribute to the inhibition of exosomal clearance, hence, increasing the on-target effect. Some candidate molecules that could exert an antiphagocytic role are CD47, CD24, CD44, CD31, ß2M, PD-L1, App1, and DHMEQ. Pre- and post-isolation methods for exosome engineering are compatible with the loading of therapeutic cargo and the expression of antiphagocytic surface molecules.

Effect of obesity on biodistribution of nanoparticles.

Nanoparticles have specific features (lipophilicity, surface charge, composition and size). Studies regarding the biological behavior of nanoparticles in diseases such diabetics and obesity are scarce. Here, we evaluated two nanoparticles: magnetic core mesoporous silica (MSN) (58 nm) and polycaprolactone (PCL) nanoparticle (280 nm) in obese mice. Changes in the biodistribution were observed, especially considering the mononuclear phagocyte system (MPS), and the visceral fat tissue. Nonetheless, our data corroborates the influence of size in the biodistribution in obese animals, supporting that smaller nanoparticles, may show a higher tissue deposition at spleen, due the associated splenomegaly and the complications arising from this state. Finally, our study demonstrated that, in obesity, probably due the low-grade inflammatory state associated with metabolic syndrome a difference in accumulation of nanoparticles was found, with profound impact in the tissue deposition of nanoparticles.

Morphological Analysis of Reticuloendothelial System in Capuchin Monkeys (Sapajus spp.) after Meso-2,3-Dimercaptosuccinic Acid (DMSA) Coated Magnetic Nanoparticles Administration.

Magnetic nanoparticles can be used for numerous in vitro and in vivo applications. However, since uptake by the reticuloendothelial system represents an obstacle for the achievement of nanoparticle diagnostic and therapeutic goals, the aim of the present study was to evaluate the uptake of dimercaptosuccinic acid coated magnetic nanoparticles by reticuloendothelial system phagocytic cells present in lymph nodes, spleen, and liver tissue and how the presence of these particles could have an impact on the morphology of these organs in capuchin monkeys (Sapajus spp.). Animals were intravenously injected with dimercaptosuccinic acid coated magnetic nanoparticles and euthanized 12 hours and 90 days post-injection. Organs were processed by transmission electron microscopy and histological techniques. Samples of spleen and lymph nodes showed no morphological changes. Nevertheless, liver samples collected 90 days post-administration showed slight morphological alteration in space of Disse. Moreover, morphometrical analysis of hepatic mitochondria was performed, suggesting a clear positive correlation between mitochondrial area and dimercaptosuccinic acid coated magnetic nanoparticles administration time. The present results are directly relevant to current safety considerations in clinical diagnostic and therapeutic uses of magnetic nanoparticles.

Study of enzyme replacement therapy for Gaucher Disease: comparative analysis of clinical and laboratory parameters at diagnosis and after two, five and ten years of treatment

Objective: To evaluate the impact of enzyme replacement therapy for Gaucher Disease on clinical and laboratory parameters after two, five and ten years of treatment. Methods: Data were collected from patient records and analyzed using BioEstat software (version 5.0). Student's t-test, Analysis of Variance (ANOVA), Wilcoxon test and Kruskal–Wallis test were used for statistical analysis. Hepatomegaly and splenomegaly were analyzed using the Kappa test. Results: There was a significant increase in hemoglobin levels (p-value <0.01) and platelet counts (p-value = 0.01) within two years of therapy. At the same time, the frequencies of splenomegaly (p-value <0.01) and hepatomegaly (p-value <0.05) reduced. These results were similar at five and ten years of enzyme replacement therapy. Conclusions: There are substantial and quick (within two years) laboratory and clinical responses to enzyme replacement therapy. These improvements continue as long as enzyme replacement therapy is administered every two weeks, as recommended by the literature...

Infection cycle of Salmonella enterica serovar Enteritidis in latent carrier mice.

This work reports the distribution of an oral dose of Salmonella enterica serovar Enteritidis (SE) in C57Bl/6-Bcgr mice, to study its pathogenesis in a latent carrier animal. Mice orally inoculated with a high dose of SE developed a latent infection characterized by the absence of clinical symptoms in which the cecum is functioning as a "strategic site" of SE proliferation, releasing bacteria into feces intermittently over the 4-week study. A sequence of disruptions occurred in the small intestine at 1 day postinculation (PI). The microvilli exhibited different degrees of degeneration, which were reversible as the cells became vacuolated. From 2 days PI, SE was detected in the mononuclear phagocytic system, and an exponential growth of the remaining bacteria in tissues was observed until 4 days PI. The production of interferon gamma from 3 days PI is restricting the SE growth, and a plateau phase was observed from 4 to 15 days PI. A recurrence of the bacterial growth in tissue occurred from 15 to 28 days PI, especially in the cecum. Increasing our knowledge about the host-pathogen interaction of adapted pathogens with the ability to develop latency is essential for the development of an efficient strategy for Salmonella control.

Influence of the acute alcoholism on the phagocytic function of the mononuclear phagocytic system.

RATIONALE: Alcoholics are more likely to have infections, mainly in the respiratory system. Alcohol seems to inhibit the immune system. Despite the extensive literature related to alcoholism, data related to the immune system are still not conclusive. OBJECTIVE: The purpose of this study was to verify the influence of acute alcohol intake on colloid distribution in the organs of the mononuclear phagocyte system. METHODS AND RESULTS: Thirteen male Swiss mice were divided into two groups: Group 1 (n = 5) - control, and Group 2 (n = 8) - animals that received 0.5 ml ethanol 50%, 30 minutes before the experiment. Colloidal sulphur labeled with 99mTc was used to evaluate colloid distribution in the liver, spleen and lungs. Colloid clearance was assessed as well. A gamma camera was used to measure the radioactivity of these organs and of a blood clot. No difference was found in the presence of colloid in the organs of both groups. The liver showed the highest phagocytic intake, followed by the spleen and lungs (p = 0.021 for Group 1 and p = 0.003 for Group 2). A minimum amount of radiation remained in the blood of both groups. DISCUSSION: According to the experiential conditions of this work, acute ingestion of alcohol did not interfere with the phagocytic function of the mononuclear phagocyte system in mice.

Oral lichen planus and dermal dendrocytes.

INTRODUCTION: Oral lichen planus (OLP) is a relatively common inflammatory disease with a wide range of clinical forms. Its pathogenesis has not been fully elucidated although it is known to be mediated by lymphocytes with the participation of cytokines and other inflammatory cells, including type I and type II dermal dendrocytes (DD) (factor XIIIa+ DD and CD34+ DD, respectively). OBJECTIVES: To describe the presence and tissue distribution of these cells, through immunohistochemistry, in 23 specimens from patients with clinical and histopathological criteria of OLP. RESULTS: Factor XIIIa+ DD were mainly located in the superficial dermis (p < 0.0001) as opposed to the deep submucosa. These cells were abundant throughout the dermal-epidermal junction and closely related to lymphocyte infiltration. Moreover, factor XIIIa+ DD were also found in the epithelium and deep dermis. CD34+ DD were distributed mostly to the deep dermis directly below the lymphocyte infiltrate with few cells in the subepithelial region. CONCLUSIONS: DD were present in OLP, with distinct tissue distributions. Factor XIIIa+ DD were predominant in the superficial dermis while CD34+ DD could be found mostly in the deep dermis. These findings suggest that DD, and those positive for factor XIIIa+ in particular in view of their ability to express intercellular adhesion molecule-1 (ICAM-1) and tumor necrosis factor alpha (TNF-alpha), may play an important role in pathogenesis of OLP.

Methylenedioxymethamphetamine (Ecstasy) decreases neutrophil activity and alters leukocyte distribution in bone marrow, spleen and blood.

OBJECTIVE: Looking for possible neuroimmune relationships, we analyzed the effects of methylenedioxymethamphetamine (MDMA) administration on neuroendocrine, neutrophil activity and leukocyte distribution in mice. METHODS: Five experiments were performed. In the first, mice were treated with MDMA (10 mg/kg) 30, 60 min and 24 h prior to blood sample collection for neutrophil activity analysis. In the second experiment, the blood of naïve mice was collected and incubated with MDMA for neutrophil activity in vitro analysis. In the third and fourth experiments, mice were injected with MDMA (10 mg/kg) and 60 min later, blood and brain were collected to analyze corticosterone serum levels and hypothalamic noradrenaline (NA) levels and turnover. In the last experiment, mice were injected with MDMA 10 mg/kg and 60 min later, blood, bone marrow and spleen were collected for leukocyte distribution analysis. RESULTS: Results showed an increase in hypothalamic NA turnover and corticosterone serum levels 60 min after MDMA (10 mg/kg) administration, a decrease in peripheral blood neutrophil oxidative burst and a decrease in the percentage and intensity of neutrophil phagocytosis. It was further found that MDMA (10 mg/kg) treatment also altered leukocyte distribution in blood, bone marrow and spleen. In addition, no effects were observed for MDMA after in vitro exposure both in neutrophil oxidative burst and phagocytosis. CONCLUSION: The effects of MDMA administration (10 mg/kg) on neutrophil activity and leukocyte distribution might have been induced indirectly through noradrenergic neurons and/or hypothalamic-pituitary-adrenal axis activations.

Infecção em cão por Brucella abortus: relato de caso / Brucella abortus infection in dog: case report

Brucella abortus infection is reported in a dog from a rural area that presented at clinical evaluation left testicular enlargement and right testicular decrease. Serum resulted negative to rapid agglutination test and agar gel immunodifusion with Brucella ovis antigen but positive to buffered plate agglutination test, tube agglutination test and 2- Mercapthoetanol with B. abortus antigen. Brucella isolation was negative in blood, testicular material, semen and urine. Brucella DNA was detected in PCR from urine and blood(AU)

Infecção em cão por Brucella abortus: relato de caso / Brucella abortus infection in dog: case report

Brucella abortus infection is reported in a dog from a rural area that presented at clinical evaluation left testicular enlargement and right testicular decrease. Serum resulted negative to rapid agglutination test and agar gel immunodifusion with Brucella ovis antigen but positive to buffered plate agglutination test, tube agglutination test and 2- Mercapthoetanol with B. abortus antigen. Brucella isolation was negative in blood, testicular material, semen and urine. Brucella DNA was detected in PCR from urine and blood

Physical training attenuates the stress-induced changes in rat T-lymphocyte function.

BACKGROUND/AIMS: Modulations in the immune function by stress are a well-known phenomenon. Acute restraint stress may induce impaired T-lymphocyte responses. Moderate physical training is associated with beneficial effects on immunological functions. We investigated the effects of a moderate physical training on T-lymphocyte function in rats submitted to acute restraint stress. METHODS: Thirty male Wistar rats weighing 210-226 g were randomly divided into four groups: non-trained rats (NT, n = 7), and non-trained rats submitted to stress (NT + S, n = 8); trained rats (T, n = 7), and trained rats submitted to stress (T + S, n = 8). Trained rats were submitted to a program of moderate running over a period of 8 weeks. Rats subjected to restraint stress were kept immobilized in glass cylinders (8 cm in diameter and 24 cm long) during 60 min. Plasma corticosterone concentration, peripheral blood leukocyte number, indicators of apoptosis of T lymphocytes in blood and lymphoid organs, and mitogen-induced proliferation of T lymphocytes in lymphoid organs were evaluated. RESULTS: Acute stress exposure raised plasma corticosterone concentration (p < 0.001), but not in previously trained animals. Restraint stress induced an increase in the percentage of lymphocytes in apoptosis, and a decrease in the concanavalin-A-induced proliferation of lymphocytes from the thymus and lymph nodes, and an increase in lymphocytes of the spleen. Neither of these alterations was observed in trained animals submitted to acute restraint stress. CONCLUSIONS: Our data confirm that acute restraint stress is associated with changes in T-lymphocyte function. Moreover, moderate physical training attenuates the effects of acute stress by a mechanism that involves the hypothalamic-pituitary-adrenal axis and an increase in tolerance of leukocytes.

Perfil de resistência da bactéria da espécie Serratia marcescens isolada de infecções hospitalares no Hospital Geral de Fortaleza ( H.G.F. ) / Resistance profile of the Serratia marcescens bacterium species isolated in hospital infections within the Fortaleza General Hospital ( H.G.F. )

Serratia marcescens é o membro mais importante desse gênero e é geralmente associado a uma variedade de infecção humana, em particular pneumonia e septicemia em pacientes com câncer reticulo endotelial que recebem quimioterapia. Às vezes,esse microrganismo também provoca infecções do trato urinário e infecções em ferimentos. Devido à virulência potencial de espéciesde Serratia, é importante que esses microrganismos sejam separados do grupo Enterobacter. A produção de Dnase extracelular detectável por espécies de Serratia é uma característica confiável, através da qual essa separação pode ser feita. O objetivo deste trabalho foi verificar o perfil de resistência de cepas de Serratia isoladas em pacientes com infecção hospitalar no Hospital Geral de Fortaleza. Foram pesquisados todos os casos de infecção hospitalar na UTI e Berçário, no período de 1o de janeiro a 30 de dezembro de 2002, no Hospital Geral de Fortaleza. As Bactérias isoladas foram identificadas por meio do aparelho de automação MicroScan. Para tal, foramutilizados Painéis Convencionais BreakPoint Combo e ID tipo 2, e painéis Convencionais Liofilizados MicroScan® Liofilizados MIC/Combo 14, destinados à determinação da susceptibilidade a agentes antimicrobianos. A UTI e o Berçário são dois locais onde ocorreram a frequência da bactéria Serratia marcescens (3,44). O setor que apresentou maior resistência a antibióticos foi o berçário,sendo resistente a vários antibióticos de ultima geração. A UTI apresentou mais sensibilidade, incluindo aos antibióticos de ultima geração.

Melatonin corrects reticuloendothelial blockade and iron status in haemodialysed patients.

AIM: Treatment of anaemia in haemodialysed patients in the setting of inflammation usually displays high levels of serum ferritin (>800 ng/mL) and low transferrin saturation (TSAT) (<20%) despite i.v. iron supplementation, thus proving iron trapping in the reticuloendothelial system. Melatonin has been reported to reduce cytokine production and, in dialysis patients, to prevent oxidative stress resulting from iron and erythropoietin treatment. METHOD: In this study, we evaluated a group of 10 patients undergoing haemodialysis who displayed elevated serum ferritin (981 +/- 44.6 ng/mL) and TSAT <20% (15.6 +/- 3.8%) after having received 1.2 g of i.v. iron dextran over a period of 8 weeks. These patients received oral melatonin, 6 mg/day at night for 30 days. RESULTS: After this treatment, all of them markedly increased TSAT values, reaching 35.5 +/- 6.7% (P < 0.0001 vs basal values). In addition, ferritin values decreased to 754.4 +/- 263.7 ng/mL (P < 0.05), and serum iron dramatically increased in all of the patients under study (42.4 +/- 9.4 vs 109.7 +/- 24.3 microg/dL; P < 0.0001). Values for haematocrit (28.6 +/- 2.7 vs 31.9 +/- 3.57%; P < 0.05) and haemoglobin (9.19 +/- 0.97 vs 10.04 +/- 1.29 g/dL; P < 0.05) were also improved. Measurements were then repeated 2 weeks after melatonin withdrawal, showing an impressive decrease in TSAT (16.4 +/- 5.3%; P < 0.00001) and serum iron (48 +/- 14.7 microg/dL; P < 0.0001) values and an almost significant increase in ferritin values (954.4 +/- 86 ng/mL; P < 0.054). CONCLUSION: The present study demonstrates that melatonin may strongly correct the reticuloendothelial blockade seen in dialysis patients under an inflammatory status, thus allowing a better management of iron derangements and renal anaemia.

Atividade fagocitária do sistema mononuclear fagocitário na gravidez / Phagocytic function of reticuloendothelial system during pregnancy

As alterações imunitárias que ocorrem durante a gravidez são ainda pouco compreendidas. Para determinar a influência da gravidez na atividade fagocitária do sistema mononuclear fagocitário (SMF) foram utilizadas vinte ratas adultas. Os animais foram divididos em dois grupos (n-10): Grupo 1 - controle, Grupo 2 - ratas prenhas. A função do sistema mononuclear fagocitário foi determinada pela captação de enxofre coloidal marcado com 99mTc pelos órgãos do SMF, além de avaliar a permanência do radiofármaco em coágulo sangüíneo. O peso e a radiação de cada amostra foram medidas. Realizou-se também análise histológica desses órgãos. Os resultados foram comparados pelo teste t de Student. Em todos os animais, a captação do radiofármaco foi maior no fígado, seguido pelo baço e pulmão. O coágulo sangüíneo apresentou uma quantidade mínima de radiação. As ratas grávidas registraram menor captação do colóide no fígado e maior captação no pulmão em relação ao grupo controle. Não foram evidenciadas alterações na histoarquitetura desses órgãos. Em rata grávida, a atividade fagocitária do SMF diminuiu no fígado, porém aumentou no pulmão.

Alterations of the immune function during thepregnancy are not well understood. To assess theinfluence of pregnancy on the phagocytic function ofthe reticuloendothelial system twenty adult female ratswere divided into two groups: Group 1 (n=10) –control, Group 2 (n=10) – pregnant rats. The assessmentof the phagocytic function of the reticuloendothelialsystem was by the uptake of sulphur colloid labeled withTc99m by the reticuloendothelial system organs as wellas to assess the permanence of the radio isotope inblood clots. The weights and radioactive levels of thesamples were measured. Histologic analyses of theseorgans were performed as well. The results werecompared using the Student t-test, with significanceat p<0.05. The scintigraphic values were higher in theliver followed by spleen and lung. The blood clotpresented with only a low amount of radiation. Thepregnant rats registered lower radiation levels in theliver and higher in the lung when compared with thecontrol group. The histo-architecture of the studiedorgans did not show any alterations. Pregnancyreduces the phagocytic function of the liver butincreases the role of the reticuloendothelial systemfunction of the lung.

Case report: severe juvenile type paracoccidioidomycosis with hepatitis C.

We present the case of a 34-year-old man with previous history of hepatitis C and severe juvenile type of paracoccidioidomycosis characterized by involvement of the reticuloendothelial system, eosinophilia, lung compromise (pleural effusion), retinal hemorrhage, and blood culture positive to Paracoccidioides brasiliensis. The immune evaluation showed four precipitation lines to P. brasiliensis by the double immunodiffusion test. Treatment with amphotericin B and itraconazol resulted in resolution of the disease.

Avaliação da função fagocitária em remanescentes de esplenectomia subtotal e auto-implante esplênico autógeno / Assessment of phagocytic function in remnants of subtotal spleen implantation

Para diminuir os efeitos adversos da esplenectomia total, abordagens conservadoras devem ser tentadas, quando for possível. Esplenectomia subtotal e auto-implantes esplênicos são boas alternativas nessa situação. O objetivo do presente estudo foi comparar as funções fagocitárias do pólo superior remanescente de esplenectomia subtotal e de tecido esplênico implantado no omento maior. Esta investigação foi conduzida em 35 ratos Holtzman adultos de ambos os sexos. Todos os animais foram submetidos a esplenectomia subtotal preservando o pólo superior suprido pelos vasos esplenogástricos e a auto-implante do segmento esplênico removido, no omento maior. A função fagocitária foi verificada por dois métodos diferentes: cintilografia com enxofre coloidal marcado com 99mTc e contagem, ao microscópio, de macrófagos que continham carbono coloidal. Durante os três primeiros meses, a fagocitose foi maior no pólo superior remanescente. Após esse período, não houve diferença entre o pólo superior e o auto-implante. Concluindo, o remanescente de esplenectomia subtotal e o auto-implante esplênico mantêm a função de filtração do baço mediante remoção de partículas coloidais do sangue

In order to diminish the adverse effects of totalsplenectomy, a conservative approach must beperformed whenever possible. Subtotal splenectomyand splenic autotransplantation are good alternativesin such cases. The purpose of the present study was tocompare the phagocytic function of the upper poleremnant of subtotal splenectomy and of autologousspleen tissue implanted into the greater omentum. Thisinvestigation was carried out on 35 adult Holtzmanrats of both sexes. All animals were submitted tosubtotal splenectomy, preserving the upper polesupplied by the splenogastric vessels and autotransplantationof the removed splenic segment on thegreater omentum. The phagocytic function of thesplenic remnants was verified by two differentmethods: scintigraphy with 99mTc sulfur colloid andmicroscopic counting of macrophages containingcarbon colloid. During the first three months, thephagocytosis was higher in the remnant upper pole.After this time, there was no difference between theupper pole and the splenic autotransplant. In conclusion,the remnant of subtotal splenectomy and the splenicautotransplant maintain the filtering function of thespleen by removing colloid particles from the blood.