RESUMEN
It has been demonstrated that expression of cyclooxygenase-2 (COX-2) isoform is induced by Entamoeba histolytica in macrophages and polymorphonuclear cells during amoebic liver abscess (ALA) formation in hamsters. Trophozoites present in the lesion were also positive for COX-2 signal. However, no cross reactivity of the anti-COX-2 antibody with protein extract of cultivated trophozoites was found. To clarify if trophozoites are involved in PGE(2) production during ALA development, COX-2 expression was detected by in situ hybridization and RT-PCR in liver tissue from intrahepatically infected hamsters. COX-2 mRNA was in polymorphonuclear cells since 4h postinfection, and subsequently, local macrophages expressed COX-2 mRNA in a similar way. Additionally, a positive signal for COX-2 mRNA expression was detected in E. histolytica trophozoites, suggesting that, in vivo, parasite COX expression may be an important mechanism to promote inflammation.
Asunto(s)
Ciclooxigenasa 2/biosíntesis , Entamoeba histolytica/enzimología , Absceso Hepático Amebiano/parasitología , Animales , Cricetinae , Ciclooxigenasa 2/genética , Sondas de ADN/normas , Dinoprostona/biosíntesis , Entamoeba histolytica/genética , Entamoeba histolytica/patogenicidad , Regulación Enzimológica de la Expresión Génica/fisiología , Interacciones Huésped-Parásitos , Inmunohistoquímica , Hibridación in Situ , Inflamación/enzimología , Inflamación/parasitología , Riñón/enzimología , Hígado/enzimología , Hígado/parasitología , Hígado/patología , Absceso Hepático Amebiano/enzimología , Absceso Hepático Amebiano/patología , Macrófagos/enzimología , Macrófagos/parasitología , Masculino , Mesocricetus , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y Especificidad , Alineación de Secuencia , Trofozoítos/enzimologíaRESUMEN
The microsatellites HEL5, HEL9, INRA063, and BM2113 were used to analyze genetic similarities and differences of geographically isolated Criollo cattle herds in Mexico. Criollo cattle from five counties within the state of Chihuahua and one county from the state of Tamaulipas (n = 60) were sampled. The five counties in Chihuahua included Cerocahui (n = 14), Chinipas (n = 10), Guachochi (n = 15), Morelos (n = 30), and Temoris (n = 9). Samples of DNA were amplified by PCR and separated on a 7% polyacrylamide gel. Microsatellite size was established by comparison to M13mp18 DNA ladder and a documented set of four bovine controls. Allele frequencies and genotypic deviations from Hardy-Weinberg equilibrium were tested using the GENEPOP program. Eleven alleles were generated at HEL5 for the populations sampled (149 to 169 bp). Allele frequencies were greatest for the 163-bp allele in Criollo cattle from Cerocahui, Chinipas, Moralos, and Tamaulipas (0.23 to 0.5). Cattle from Guachochi had an allele frequency of 0.38 for the 151-bp allele, and cattle from Temoris had an allele frequency of 0.25 for the 149- and 167-bp alleles, with no 163-bp allele. Amplification with HEL9 produced 12 alleles (145, 149 to 169 bp) and showed common high-frequency alleles at 149, 157, and 159 bp for animals from all regions. The Chinipas population showed a moderate allele frequency at 145 bp; no other regions contained this allele. For INRA063 there were five alleles with 182 and 184 bp in low frequency. For BM2113 there were 10 alleles in the Criollo cattle (125 to 143 bp), with an equal distribution of frequencies for all alleles. In two regions, Guachochi and Morelos, genotypic frequencies deviated from Hardy-Weinberg equilibrium. Cattle from the Temoris region were genetically most distant from Criollo cattle of the other five regions.