RESUMEN
Two major zymodemes from different Entamoeba histolytica strains were detected, despite different growth conditions, using isoelectrofocusing in ultrathin gels. One was associated with strains cultured from symptomatic patients, while the other was associated with microorganisms obtained from clinically symptomatic persons.
Asunto(s)
Entamoeba histolytica/enzimología , Entamebiasis/enzimología , Glucosa-6-Fosfato Isomerasa/análisis , Isoenzimas/genética , Animales , Entamoeba histolytica/genética , Entamoeba histolytica/crecimiento & desarrollo , Glucosa-6-Fosfato Isomerasa/genética , Humanos , Focalización IsoeléctricaRESUMEN
We examined the participation of polymorphonuclear leucocytes and amebic proteinases upon tissue damage by means of an experimental model of acute amebic lesions developed in rat's testicle. In leukopenic rats (less than 1,000 leucocytes/ml) intratesticular injection of axenic E. histolytica's trophozoites (HM-1) produced lesions undistinguishable from the normal controls. On the other hand, inhibition of 80% (average) of the proteinase activity by means of previous incubation of the trophozoites with human a2M gave way to minimal inflammatory lesions almost undistinguishable from the controls which were injected with PBS-A. Our data suggest that in this experimental model of acute amebiasis polymorphonuclear leukocytes do not participate in the tissue damage and that amebic proteinases are responsible for Entamoeba histolytica's virulence.
Asunto(s)
Endopeptidasas/fisiología , Entamoeba histolytica/patogenicidad , Entamebiasis/patología , Neutrófilos/fisiología , Orquitis/parasitología , Proteínas Protozoarias/metabolismo , Animales , Entamoeba histolytica/enzimología , Entamebiasis/complicaciones , Entamebiasis/enzimología , Leucopenia/inducido químicamente , Leucopenia/complicaciones , Masculino , Mecloretamina/toxicidad , Necrosis , Orquitis/complicaciones , Orquitis/patología , Inhibidores de Proteasas/farmacología , Ratas , Ratas Endogámicas , Virulencia , alfa-Macroglobulinas/farmacologíaRESUMEN
Authors report the results of the isoenzyme analysis of strains of Entamoeba histolytica isolated from international travellers. This recently developed method allows the detection of pathogenic strains by evaluating the electrophoretic mobility of cytoplasmic enzymes and was proved to be more reliable and quickly feasible than previous ones. The experience reported refers to three strains isolated from travellers coming from Ecuador, Brazil and Indonesia, respectively; the zymodeme XIX (in accordance with the Sargeaunt's classification) was identified in all the three cases. This zymodeme has been first detected in 1981 and should currently be considered rare; moreover, it has never been previously reported from the Americas.