RESUMO
This paper centers on some whole-istic organizational and functional aspects of hepatic Schistosoma mansoni granuloma, which is an extremely complex system. First, it structurally develops a collagenic topology, originated bidirectionally from an inward and outward assembly of growth units. Inward growth appears to be originated from myofibroblasts derived from small portal vessel around intravascular entrapped eggs, while outward growth arises from hepatic stellate cells. The auto-assembly of the growth units defines the three-dimensional scaffold of the schistosome granulomas. The granuloma surface irregularity and its border presented fractal dimension equal to 1.58. Second, it is internally regulated by intricate networks of immuneneuroendocrine stimuli orchestrated by leptin and leptin receptors, substance P and Vasoactive intestinal peptide. Third, it can reach the population of ± 40,000 cells and presents an autopoietic component evidenced by internal proliferation (Ki-67+ Cells), and by expression of c-Kit+ Cells, leptin and leptin receptor (Ob-R), granulocyte-colony stimulating factor (G-CSF-R), and erythropoietin (Epo-R) receptors. Fourth, the granulomas cells are intimately connected by pan-cadherins, occludin and connexin-43, building a state of closing (granuloma closure). In conclusion, the granuloma is characterized by transitory stages in such a way that its organized structure emerges as a global property which is greater than the sum of actions of its individual cells and extracellular matrix components.
Assuntos
Animais , Camundongos , Granuloma/patologia , Hepatopatias Parasitárias/patologia , Schistosoma mansoni/fisiologia , Esquistossomose mansoni/patologia , Modelos Animais de Doenças , Técnica Indireta de Fluorescência para Anticorpo , Fractais , Granuloma/metabolismo , Granuloma/parasitologia , Hepatopatias Parasitárias/metabolismo , Hepatopatias Parasitárias/parasitologia , Coloração e Rotulagem , Esquistossomose mansoni/metabolismo , Esquistossomose mansoni/parasitologia , Fatores de TempoRESUMO
We have previously showed that Schistosoma mansoni ATP-diphosphohydrolase and Solanum tuberosum potato apyrase share epitopes and the vegetable protein has immunostimulatory properties. Here, it was verified the in situ cross-immunoreactivity between mice NTPDases and anti-potato apyrase antibodies produced in rabbits, using confocal microscopy. Liver samples were taken from Swiss Webster mouse 8 weeks after infection with S. mansoni cercariae, and anti-potato apyrase and TRITC-conjugated anti-rabbit IgG antibody were tested on cryostat sections. The results showed that S. mansoni egg ATP diphosphohydrolase isoforms, developed by anti-potato apyrase, are expressed in miracidial and egg structures, and not in granulomatous cells and hepatic structures (hepatocytes, bile ducts, and blood vessels). Therefore, purified potato apyrase when inoculated in rabbit generates polyclonal sera containing anti-apyrase antibodies that are capable of recognizing specifically S. mansoni ATP diphosphohydrolase epitopes, but not proteins from mammalian tissues, suggesting that autoantibodies are not induced during potato apyrase immunization. A phylogenetic tree obtained for the NTPDase family showed that potato apyrase had lower homology with mammalian NTPDases 1-4, 7, and 8. Further analysis of potato apyrase epitopes could implement their potential use in schistosomiasis experimental models.
Assuntos
Animais , Masculino , Camundongos , Coelhos , Adenosina Trifosfatases/imunologia , Apirase/imunologia , Schistosoma mansoni/enzimologia , Esquistossomose mansoni/imunologia , Solanum tuberosum/enzimologia , Sequência de Aminoácidos , Adenosina Trifosfatases/metabolismo , Anticorpos Anti-Helmínticos/imunologia , Apirase/metabolismo , Reações Cruzadas , Modelos Animais de Doenças , Microscopia Confocal , Dados de Sequência Molecular , Schistosoma mansoni/imunologia , Schistosoma mansoni/metabolismoRESUMO
This paper centers on some whole-istic organizational and functional aspects of hepatic Schistosoma mansoni granuloma, which is an extremely complex system. First, it structurally develops a collagenic topology, originated bidirectionally from an inward and outward assembly of growth units. Inward growth appears to be originated from myofibroblasts derived from small portal vessel around intravascular entrapped eggs, while outward growth arises from hepatic stellate cells. The auto-assembly of the growth units defines the three-dimensional scaffold of the schistosome granulomas. The granuloma surface irregularity and its border presented fractal dimension equal to 1.58. Second, it is internally regulated by intricate networks of immuneneuroendocrine stimuli orchestrated by leptin and leptin receptors, substance P and Vasoactive intestinal peptide. Third, it can reach the population of +/- 40,000 cells and presents an autopoietic component evidenced by internal proliferation (Ki-67+ Cells), and by expression of c-Kit+ Cells, leptin and leptin receptor (Ob-R), granulocyte-colony stimulating factor (G-CSF-R), and erythropoietin (Epo-R) receptors. Fourth, the granulomas cells are intimately connected by pan-cadherins, occludin and connexin-43, building a state of closing (granuloma closure). In conclusion, the granuloma is characterized by transitory stages in such a way that its organized structure emerges as a global property which is greater than the sum of actions of its individual cells and extracellular matrix components.
Assuntos
Granuloma/patologia , Hepatopatias Parasitárias/patologia , Schistosoma mansoni/fisiologia , Esquistossomose mansoni/patologia , Animais , Modelos Animais de Doenças , Técnica Indireta de Fluorescência para Anticorpo , Fractais , Granuloma/metabolismo , Granuloma/parasitologia , Hepatopatias Parasitárias/metabolismo , Hepatopatias Parasitárias/parasitologia , Camundongos , Esquistossomose mansoni/metabolismo , Esquistossomose mansoni/parasitologia , Coloração e Rotulagem , Fatores de TempoRESUMO
We have previously showed that Schistosoma mansoni ATP-diphosphohydrolase and Solanum tuberosum potato apyrase share epitopes and the vegetable protein has immunostimulatory properties. Here, it was verified the in situ cross-immunoreactivity between mice NTPDases and anti-potato apyrase antibodies produced in rabbits, using confocal microscopy. Liver samples were taken from Swiss Webster mouse 8 weeks after infection with S. mansoni cercariae, and anti-potato apyrase and TRITC-conjugated anti-rabbit IgG antibody were tested on cryostat sections. The results showed that S. mansoni egg ATP diphosphohydrolase isoforms, developed by anti-potato apyrase, are expressed in miracidial and egg structures, and not in granulomatous cells and hepatic structures (hepatocytes, bile ducts, and blood vessels). Therefore, purified potato apyrase when inoculated in rabbit generates polyclonal sera containing anti-apyrase antibodies that are capable of recognizing specifically S. mansoni ATP diphosphohydrolase epitopes, but not proteins from mammalian tissues, suggesting that autoantibodies are not induced during potato apyrase immunization. A phylogenetic tree obtained for the NTPDase family showed that potato apyrase had lower homology with mammalian NTPDases 1-4, 7, and 8. Further analysis of potato apyrase epitopes could implement their potential use in schistosomiasis experimental models.
Assuntos
Adenosina Trifosfatases/imunologia , Apirase/imunologia , Schistosoma mansoni/enzimologia , Esquistossomose mansoni/imunologia , Solanum tuberosum/enzimologia , Adenosina Trifosfatases/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos Anti-Helmínticos/imunologia , Apirase/metabolismo , Reações Cruzadas , Modelos Animais de Doenças , Masculino , Camundongos , Microscopia Confocal , Dados de Sequência Molecular , Coelhos , Schistosoma mansoni/imunologia , Schistosoma mansoni/metabolismoRESUMO
The fact that the Schistosoma mansoni egg has two ATP diphosphohydrolase (EC 3.6.1.5) isoforms with different net charges and an identical molecular weight of 63,000, identified by non-denaturing polyacrylamide gel electrophoresis and immunological cross-reactivity with potato apyrase antibodies, is shown. In soluble egg antigen (SEA), only the isoform with the lower net negative charge was detected and seemed to be the predominant species in this preparation. By confocal fluorescence microscopy, using anti-potato apyrase antibodies, the S. mansoni egg ATP diphosphohydrolase was detected on the external surface of miracidium and in von Lichtenberg's envelope. Intense fluorescence was also seen in the outer side of the egg-shell, entrapped by the surface microspines, suggesting that a soluble isoform is secreted. ATP diphosphohydrolase antigenicity was tested using the vegetable protein as antigen. The purified potato apyrase was recognized in Western blots by antibodies present in sera from experimentally S. mansoni-infected mice. In addition, high levels of IgG anti-ATP diphosphohydrolase antibodies were detected by ELISA in the same sera. This work represents the first demonstration of antigenic properties of S. mansoni ATP diphosphohydrolase and immunological cross-reactivity between potato apyrase and sera from infected individuals.
Assuntos
Antígenos de Helmintos/química , Apirase/química , Schistosoma mansoni/enzimologia , Animais , Antígenos de Helmintos/isolamento & purificação , Antígenos de Helmintos/metabolismo , Apirase/imunologia , Apirase/isolamento & purificação , Apirase/metabolismo , Western Blotting , Eletroforese em Gel de Poliacrilamida , Imuno-Histoquímica , Isoenzimas , Fígado/parasitologia , Camundongos , Microscopia de Fluorescência , Peso Molecular , Schistosoma mansoni/imunologia , Schistosoma mansoni/metabolismoRESUMO
Human abdominal angiostrongyliasis is a severe eosinophilic disease caused by Angiostrongylus costaricensis. Previous studies have demonstrated that wild rodents are critically involved as definitive hosts to this nematode in nature. In this study, we have evaluated the susceptibility of Wistar rats (Rattus norvegicus) to A. costaricensis infection. Kinetics of parasitological and pathological changes, including the number of adult worms recovered from mesenteric arteries, and of IgE, mast cell and eosinophil levels in several compartments have been assessed. The oral inoculation of third-stage larvae (L3) into adult Wistar rats led to a marked accumulation of worms in the branches of the mesenteric arteries 25 and 50 days post-inoculation. Intense bone marrow eosinophilia ranging from 7 to 50 days was accompanied by marked accumulation of eosinophils in the blood, peritoneal and bronchoalveolar spaces. Eosinophilic periarteritis, oedema and granuloma in the intestinal and lung tissues were also histologically evident. Total serum IgE and specific anti-parasite IgE peaked at 25 days post-infection, as measured by ELISA and by the passive cutaneous anaphylaxis test, respectively. At that time point, there was a drastic reduction in the number of intact mast cells in the peritoneal effluent. These findings indicate that Wistar rats are permissive to A. costaricensis infection. IgE-mast cell activation and massive tissue eosinophil infiltration are marked features in the process and are likely to play a crucial role in the immune-response evoked by this parasite.
Assuntos
Angiostrongylus/imunologia , Eosinófilos/patologia , Imunoglobulina E/imunologia , Mastócitos/patologia , Infecções por Strongylida/imunologia , Animais , Ensaio de Imunoadsorção Enzimática , Cinética , Cavidade Peritoneal , Artéria Pulmonar/parasitologia , Ratos , Ratos Wistar , Infecções por Strongylida/patologiaRESUMO
We previously reported that portal veins from mice infected with male Schistosoma mansoni exhibited an increased reactivity to 5-hydroxytryptamine (5-HT). Here, we extended our observations to mice infected by both male and female worms and we further investigated another constrictor agent and the mechanism(s) responsible for the enhanced maximal contraction ( E(max)). Bisexual infection increased the E(max) of 5-HT (from 0.66+/-0.06 mN.s to 1.56+/-0.38 mN.s), in a similar way to the unisexual (male) infection. Infection with male worms increased portal vein reactivity to acetylcholine, as revealed by a higher E(max) (1.03+/-0.2 mN.s) in relation to non-infected control animals ( E(max)= 0.54+/-0.08 mN.s). Sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase (SERCA) inhibition with 100 nM thapsigargin reduced the E(max) of 5-HT by 35% in both tissues, discharging a deficiency of SERCA pump in infected animals. In contrast, the number of voltage-dependent Ca(2+) channels (L-type) was higher in portal veins from infected than non-infected control mice. Inhibition of Ca(2+)-activated chloride channels (Cl(Ca)) with 10 micro M niflumic acid reduced the E(max) of 5-HT in portal veins more from infected than non-infected animals (remaining tension = 60.9+/-2.2% and 70.4+/-2.3%, respectively). Histopathological analysis revealed an increased content of collagen and elastin in portal veins from male S. mansoni-infected mice, compatible with an increased intraluminal pressure. In conclusion, male S. mansoni altered portal vein physiology, increasing the E(max) of two vasoconstrictors, possibly by increasing membrane depolarisation through a more effective opening of Cl(Ca) channels, with calcium entering through L-type Ca(2+) channels.
Assuntos
Veia Porta/fisiopatologia , Schistosoma mansoni/patogenicidade , Esquistossomose mansoni/fisiopatologia , Vasoconstrição , Acetilcolina/farmacologia , Animais , Cálcio/metabolismo , Relação Dose-Resposta a Droga , Feminino , Histocitoquímica , Masculino , Camundongos , Veia Porta/citologia , Veia Porta/patologia , Retículo Sarcoplasmático/efeitos dos fármacos , Retículo Sarcoplasmático/metabolismo , Esquistossomose mansoni/metabolismo , Esquistossomose mansoni/parasitologia , Esquistossomose mansoni/patologia , Serotonina/farmacologia , Fatores Sexuais , CaramujosRESUMO
The objective of the present study was to investigate whether the injection of a tolerated protein (indirect effects) affects the formation of granulomas around Schistosoma mansoni eggs trapped in the lungs after intravenous (iv) injection into normal (noninfected) C57BL/6 mice (6 animals per group). To induce oral tolerance to chicken egg ovalbumin a 1/5 dilution of egg white in water was offered ad libitum in a drinking bottle for 3 days. Control mice received water. After 7 days, control and experimental animals were injected iv with 2,000 S. mansoni eggs through a tail vein. In some mice of both groups the iv injection of eggs was immediately followed by intraperitoneal (ip) immunization with 10 micro g of dinitrophenylated conjugates of ovalbumin (DNP-Ova) emulsified in complete Freund's adjuvant (CFA) or only CFA; 18 days later, mice were bled and killed by ether inhalation. The lungs were fixed in formalin and embedded in paraffin. Serial sections of 5 m were stained with Giemsa, Gomori's silver reticulin and Sirius red (pH 10.2). Granuloma diameters were measured in histological sections previously stained with Gomori's reticulin. Anti-DNP and anti-soluble egg antigen (SEA) antibodies were analyzed by ELISA. In mice orally tolerant to ovalbumin the concomitant ip injection of DNP-Ova resulted in significantly lower anti-SEA antibodies (ELISA*: 1395 +/- 352 in non-tolerant and 462 +/- 146 in tolerant mice) and affected granuloma formation around eggs, significantly decreasing granuloma size (area: 22,260 +/- 2478 to 12,993 +/- 3242 m ). Active mechanisms triggered by injection of tolerated antigen (ovalbumin) reduce granuloma formation.
Assuntos
Antígenos de Helmintos/imunologia , Dinitrofenóis/imunologia , Granuloma/parasitologia , Haptenos/imunologia , Pneumopatias Parasitárias/imunologia , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Schistosoma mansoni/imunologia , Administração Oral , Animais , Dinitrofenóis/administração & dosagem , Ensaio de Imunoadsorção Enzimática , Granuloma/imunologia , Granuloma/patologia , Haptenos/administração & dosagem , Tolerância Imunológica , Pneumopatias Parasitárias/patologia , Camundongos , Camundongos Endogâmicos BALB CRESUMO
The objective of the present study was to investigate whether the injection of a tolerated protein (indirect effects) affects the formation of granulomas around Schistosoma mansoni eggs trapped in the lungs after intravenous (iv) injection into normal (noninfected) C57BL/6 mice (6 animals per group). To induce oral tolerance to chicken egg ovalbumin a 1/5 dilution of egg white in water was offered ad libitum in a drinking bottle for 3 days. Control mice received water. After 7 days, control and experimental animals were injected iv with 2,000 S. mansoni eggs through a tail vein. In some mice of both groups the iv injection of eggs was immediately followed by intraperitoneal (ip) immunization with 10 æg of dinitrophenylated conjugates of ovalbumin (DNP-Ova) emulsified in complete Freund's adjuvant (CFA) or only CFA; 18 days later, mice were bled and killed by ether inhalation. The lungs were fixed in formalin and embedded in paraffin. Serial sections of 5 æm were stained with Giemsa, Gomori's silver reticulin and Sirius red (pH 10.2). Granuloma diameters were measured in histological sections previously stained with Gomori's reticulin. Anti-DNP and anti-soluble egg antigen (SEA) antibodies were analyzed by ELISA. In mice orally tolerant to ovalbumin the concomitant ip injection of DNP-Ova resulted in significantly lower anti-SEA antibodies (ELISA*: 1395 ± 352 in non-tolerant and 462 ± 146 in tolerant mice) and affected granuloma formation around eggs, significantly decreasing granuloma size (area: 22,260 ± 2478 to 12,993 ± 3242 æmý). Active mechanisms triggered by injection of tolerated antigen (ovalbumin) reduce granuloma formation
Assuntos
Animais , Camundongos , Antígenos de Helmintos , Pneumopatias Parasitárias , Ovalbumina , Schistosoma mansoni , Administração Oral , Ensaio de Imunoadsorção Enzimática , Tolerância Imunológica , Pneumopatias Parasitárias , Camundongos Endogâmicos BALB C , OvalbuminaRESUMO
Mast cells and eosinophils actively participate in tissue repair and are prominent components of Schistosoma mansoni granulomas. Since pentoxifillyne (PTX) is an immunomodulatory and antifibrotic substance, we aimed to characterize, by morphological techniques, the effect of this drug on fibrosis developed inside murine hepatic schistosomal granulomatous reaction, beyond the quantification of eosinophil and mast cell populations. The drug (1 mg/100 g animal weight) was administrated from 35 to 90 days post-infection, when the animals were killed. The intragranulomatous interstitial collagen network was analyzed by confocal laser scanning microscopy, the number of eosinophils and mast cells was quantified and the results were validated by t-student test. Treatment did not interfere on the granuloma evolution but caused a significant decrease in the total and involutive number of hepatic granulomas (p = 0.01 and 0.001, respectively), and in the intragranulomatous accumulation of eosinophils (p = 0.0001). Otherwise, the number of mast cells was not significantly altered (p = 0.9); however, it was positively correlated with the number of granulomatous structures (r = 0.955). In conclusion, PTX does not affect development and collagen deposition in S. mansoni murine granuloma, but decreases the intragranulomatous eosinophil accumulation possibly due to its immunomodulatory capability, interfering in cellular recruitment and/or differentiation.