scholarly journals Protection against Invasive Amebiasis by a Single Monoclonal Antibody Directed against a Lipophosphoglycan Antigen Localized on the Surface of Entamoeba histolytica

1997 ◽  
Vol 186 (9) ◽  
pp. 1557-1565 ◽  
Author(s):  
Alexandra Marinets ◽  
Tonghai Zhang ◽  
Nancy Guillén ◽  
Pierre Gounon ◽  
Barbara Bohle ◽  
...  
Keyword(s):  
Entamoeba Histolytica ◽  
Liver Abscess ◽  
Passive Immunization ◽  
Outer Face ◽  
Protective Capacity ◽  
Con A ◽  
Entamoeba Dispar ◽  
Confocal Immunofluorescence ◽  
Scid Mouse Model ◽  
First Time

A panel of monoclonal antibodies was raised from mice immunized with a membrane preparation from Entamoeba histolytica, the pathogenic species causing invasive amebiasis in humans. Antibody EH5 gave a polydisperse band in immunoblots from membrane preparations from different E. histolytica strains, and a much weaker signal from two strains of the nonpathogenic species Entamoeba dispar. Although the exact chemical structure of the EH5 antigen is not yet known, the ability of the antigen to be metabolically radiolabeled with [32P]phosphate or [3H]glucose, its sensitivity to digestion by mild acid and phosphatidylinositol-specific phospholipase C, and its specific extraction from E. histolytica trophozoites by a method used to prepare lipophosphoglycans from Leishmania showed that it could be classified as an amebal lipophosphoglycan. Confocal immunofluorescence and immunogold labeling of trophozoites localized the antigen on the outer face of the plasma membrane and on the inner face of internal vesicle membranes. Antibody EH5 strongly agglutinated amebas in a similar way to concanavalin A (Con A), and Con A bound to immunoaffinity-purified EH5 antigen. Therefore, surface lipophosphoglycans may play an important role in the preferential agglutination of pathogenic amebas by Con A. The protective ability of antibody EH5 was tested in a passive immunization experiment in a severe combined immunodeficient (SCID) mouse model. Intrahepatic challenge of animals after administration of an isotype-matched control antibody or without treatment led to the development of a liver abscess in all cases, whereas 11 out of 12 animals immunized with the EH5 antibody developed no liver abscess. Our results demonstrate the importance and, for the first time, the protective capacity of glycan antigens on the surface of the amebas.

scholarly journals Expression of Amoebapores Is Required for Full Expression of Entamoeba histolytica Virulence in Amebic Liver Abscess but Is Not Necessary for the Induction of Inflammation or Tissue Damage in Amebic Colitis

2004 ◽  
Vol 72 (2) ◽  
pp. 678-683 ◽  
Author(s):  
Xiaochun Zhang ◽  
Zhi Zhang ◽  
Diane Alexander ◽  
Rivka Bracha ◽  
David Mirelman ◽  
...  
Keyword(s):  
Mouse Model ◽  
Entamoeba Histolytica ◽  
Liver Abscess ◽  
Tissue Damage ◽  
Scid Mouse ◽  
Amebic Liver Abscess ◽  
Amphipathic Peptides ◽  
Amebic Colitis ◽  
Scid Mouse Model ◽  
Cellular Lysis

ABSTRACT Entamoeba histolytica trophozoites produce amoebapores, a family of small amphipathic peptides capable of insertion into bacterial or eukaryotic membranes and causing cellular lysis. Recently, E. histolytica trophozoites that are totally deficient in the production of amoebapore-A were created through a gene silencing mechanism (R. Bracha, Y. Nuchamowitz, and D. Mirelman, Eukaryot. Cell 2:295-305, 2003). Here we tested the virulence of amoebapore A(−) trophozoites in models of the two major forms of amebic disease: amebic liver abscess and amebic colitis. We demonstrate that amoebapore expression is required for full virulence in the SCID mouse model of amebic liver abscess, but E. histolytica trophozoites that do not express amoebapore-A can still cause inflammation and tissue damage in infected human colonic xenografts. These data are consistent with the concept that tissue damage may proceed by different mechanisms in amebic liver abscess compared to amebic colitis.

scholarly journals Diagnosis of Amebic Liver Abscess and Intestinal Infection with the TechLab Entamoeba histolytica II Antigen Detection and Antibody Tests

2000 ◽  
Vol 38 (9) ◽  
pp. 3235-3239 ◽  
Author(s):  
Rashidul Haque ◽  
Nasir Uddin Mollah ◽  
Ibne Karim M. Ali ◽  
Khorshed Alam ◽  
Aleida Eubanks ◽  
...  
Keyword(s):  
Entamoeba Histolytica ◽  
Liver Abscess ◽  
Positive Culture ◽  
Antigen Detection ◽  
Pcr Analysis ◽  
Amebic Liver Abscess ◽  
Intestinal Infection ◽  
Entamoeba Dispar ◽  
Stool Specimens ◽  
Culture Negative

A noninvasive diagnostic test for amebic liver abscess is needed, because amebic and bacterial abscesses appear identical on ultrasound or computer tomography and because it is rarely possible to identifyEntamoeba histolytica in stool specimens from patients with amebic liver abscess. Here we report a method of detection in serum of circulating E. histolytica Gal/GalNAc lectin to diagnose amebic liver abscess, which was used in patients from Dhaka, Bangladesh. The TechLab E. histolytica II test (which differentiates the true pathogen E. histolytica fromEntamoeba dispar) detected Gal/GalNAc lectin in the sera of 22 of 23 (96%) amebic liver abscess patients tested prior to treatment with the antiamebic drug metronidazole and 0 of 70 (0%) controls. After 1 week of treatment with metronidazole, 9 of 11 (82%) patients became serum lectin antigen negative. The sensitivity of the E. histolytica II antigen detection test for intestinal infection was also evaluated. Antigen detection identified E. histolytica infection in 50 samples from 1,164 asymptomatic preschool children aged 2 to 5 years, including 16 of 16 (100%) culture-positive specimens. PCR analysis of stool specimens was used to confirm that most antigen-positive but culture-negative specimens were true-positive: PCR identified parasite DNA in 27 of 34 (79%) of the antigen-positive, culture-negative stool specimens. Antigen detection was a more sensitive test for infection than antilectin antibodies, which were detected in only 76 of 98 (78%) amebic liver abscess patients and in 26 of 50 (52%) patients with intestinal infection. We conclude that the TechLab E. histolytica II kit is a sensitive means to diagnose hepatic and intestinal amebiasis prior to the institution of metronidazole treatment.

scholarly journals Curcumin Provides Hepatoprotection against Amoebic Liver Abscess Induced by Entamoeba histolytica in Hamster: Involvement of Nrf2/HO-1 and NF-κB/IL-1β Signaling Pathways

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
José Roberto Macías-Pérez ◽  
Liseth Rubí Aldaba-Muruato ◽  
Sandra Luz Martínez-Hernández ◽  
Martín Humberto Muñoz-Ortega ◽  
Julieta Pulido-Ortega ◽  
...  
Keyword(s):  
Entamoeba Histolytica ◽  
Liver Abscess ◽  
Liver Damage ◽  
Glycogen Content ◽  
Current Knowledge ◽  
The Other ◽  
Amoebic Liver Abscess ◽  
Normal Appearance ◽  
Hamster Model ◽  
First Time

Amoebic liver abscess (ALA) is the most common extraintestinal amoebiasis caused by Entamoeba histolytica (E. histolytica). However, despite current knowledge and scientific advances about this infection, there are no effective treatments to prevent it. Herein, the antiamoebic capacity of curcumin in a hamster model was evaluated. Curcumin (150 mg/kg, p.o., daily during 10 days before infection) considerably prevents liver damage induced at 12 and 48 h post-intrahepatic inoculation of trophozoites and decreases ALT, ALP, and γ-GTP activities, and macroscopic and microscopic observations were consistent with these results. On the other hand, after one week of intraportal inoculation, liver damage was prevented by curcumin (150 mg/kg, p.o., daily, 20 days before amoebic inoculation and during the week of infection); liver/body weight ratios and tissue and histological stains showed normal appearance; in addition, the increases in ALT, ALP, and γ-GTP activities were prevented; the depletion of glycogen content induced by the amoebic damage was partially but significantly prevented, while NF-κB activity was inhibited and the expression of IL-1β was reduced; Nrf2 production showed a tendency to increase it, and HO-1 protein was overexpressed. These results suggest for the first time that curcumin can be a compound with antiamoebic effect in the liver, suggesting that its daily use could help greatly decrease the incidence of this type of infection.

scholarly journals Entamoeba histolytica acetyl–CoA synthetase: biomarker of acute amoebic liver abscess

2014 ◽  
Vol 4 (6) ◽  
pp. 446-450
Author(s):  
Lim Boon Huat ◽  
Alfonso Olivos Garcia ◽  
Tan Zi Ning ◽  
Wong Weng Kin ◽  
Rahmah Noordin ◽  
...  
Keyword(s):  
Entamoeba Histolytica ◽  
Liver Abscess ◽  
Amoebic Liver Abscess ◽  
Acetyl Coa

scholarly journals Detección y diferenciación de Entamoeba histolytica y Entamoeba dispar mediante reacción en cadena de la polimerasa en individuos de una comunidad del Estado Zulia, Venezuela

2009 ◽  
Vol 25 (1) ◽  
pp. 151-159 ◽  
Author(s):  
Zulbey Rivero ◽  
Ángela Bracho ◽  
Marinella Calchi ◽  
Iris Díaz ◽  
Ellen Acurero ◽  
...  
Keyword(s):  
Entamoeba Histolytica ◽  
Entamoeba Dispar ◽  
Para Determinar ◽  
Los Grupos

La identificación diferencial de Entamoeba histolytica y Entamoeba dispar es esencial para un tratamiento adecuado del paciente y con fines epidemiológicos. Para determinar la prevalencia de E. histolytica y E. dispar se estandarizó y aplicó un ensayo de PCR, utilizando oligonucleótidos específicos para cada especie. 204 muestras de heces de individuos de la comunidad de Santa Rosa de Agua (Municipio Maracaibo, Estado Zulia, Venezuela), fueron analizadas a través del examen directo con SSF (0,85%) y lugol, concentrado de formol-éter y PCR. Al examen microscópico, 42 individuos (20,58%) presentaron formas evolutivas del complejo E. histolytica/E. dispar; mientras que la técnica de PCR evidenció un total de 47 casos positivos a estas amibas; de los cuales 22 eran portadores de E. histolytica (10,78%), 16 (7,84%) de E. dispar y 9 (4,41%) presentaron infección mixta. No hubo diferencia significativa al relacionar las variables sexo y presencia de E. histolytica y/o E. dispar, ni con los grupos etarios. No existieron casos de estas amibas, en los menores de 2 años. La frecuencia observada de E. histolytica (31/204), demuestra el carácter endémico de la amibiasis en esta comunidad.

scholarly journals Analysis of Clinical Characteristics of 19 Patients with Endophthalmitis Caused by Liver Abscess

2021 ◽  
Author(s):  
guangsen liu ◽  
Yue Li ◽  
Wei Wang ◽  
Lei Gao
Keyword(s):  
Visual Acuity ◽  
Liver Abscess ◽  
Diagnosis And Treatment ◽  
Endogenous Endophthalmitis ◽  
Klebsiella Pneumonia ◽  
Microbial Culture ◽  
Poor Vision ◽  
Ocular Symptoms ◽  
History Of ◽  
First Time

Abstract Objective: To analyze the clinical features, treatment, and prognosis of endophthalmitis caused by a liver abscess.Methods: All cases of endogenous endophthalmitis caused by a liver abscess in our hospital in the past 7 years were analyzed retrospectively. The data collected included age, sex, history of diabetes, initial and final vision, pathogen, course of the disease, treatment, and prognosis.Results: 21 eyes of 19 patients were complicated with liver abscess. The average age was 55.9 ±9.8 years old, including 10 males (52.6%) and 9 females (44.4%), 13 patients complicated with diabetes (71.4%), 14 patients (66.7%) first went to the ophthalmology department for diagnosis and treatment and 5 with hepatobiliary surgery (33.3%). 14 patients had a fever before onset, with an average fever time of 5.8 days. Before treatment, the duration of ocular symptoms was 7.71 ±6.68 days, 5.71 ±1.25 days for patients who go to ophthalmology for diagnosis and treatment for the first time, and 12.2 ±3.58 days for patients who go to other departments. After treatment, the average visual acuity of 21 eyes was 0.013, and the average best-corrected visual acuity was 0.79. In the 21 eyes, vitreous fluid culture was positive in 7 eyes (33.3%), all of which were Klebsiella pneumonia. Among the 14 patients with fever during hospitalization, 5 cases were positive for blood microbial culture, all of which were Klebsiella pneumonia. After vitrectomy, the average visual acuity was improved by 4.90 ±2.47 letters and that of patients without vitrectomy was-0.25±0.16letters. The visual acuity of patients who underwent postoperative visual was significantly better than that of patients without postoperative visual (P＜0.096). The visual acuity of patients without vitrectomy was significantly higher than that of patients without vitrectomy (P ＜0.01). 3 eyes (33.3%) of 9 eyes in the IVI group were removed because of uncontrolled inflammation, and 1 eye of 12 eyes in the PPV group was removed because of inflammation recurrence.Conclusion: The prognosis of endogenous endophthalmitis caused by liver abscess is generally poor, but early treatment can save part of the vision. The first visit non-ophthalmology department will delay the early diagnosis of the disease. Diabetes is an important risk factor for endogenous endophthalmitis and poor vision in patients with liver abscess. Klebsiella pneumonia is the main pathogen of intraocular infection. Vitrectomy combined with vitreous injection of antibiotics can improve the prognosis. A systematic and thorough treatment of a liver abscess is of great significance to prevent the recurrence of endophthalmitis in a liver abscess.

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