RESUMO
OBJECTIVE: To study the inflammatory profile and genes involved in the response to bacterial infections in women who developed spontaneous abortion in the presence of Ureaplasma parvum. DESIGN: Cross-sectional study. SETTING: A maternal and child referral center. PATIENT(S): Eighty-nine women with spontaneous abortion and 20 women with normal vaginal delivery (control group) were studied. INTERVENTION(S): Samples of biopsied placental tissue were collected for Mollicutes detection. MAIN OUTCOME MEASURE(S): The samples were subjected to histologic analysis, immunohistochemical evaluation for macrophages and lymphocytes, cytokine quantification, and quantitative polymerase chain reaction array to evaluate the expression of 84 genes related to the innate and adaptive immune responses. RESULT(S): The presence of U. parvum in the abortion group was positively associated with the influx of polymorphonuclear cells in the placental tissue and increased concentrations of interleukin-6 and interleukin-12p70. U. parvum caused downregulation of genes involved in the immune response, such as attraction of immune cells, activation of an inflammatory response, T-helper cell 17 response activation, and activation of the complement system at the beginning and end of pregnancy. CONCLUSION: The direct action of U. parvum on placental tissue altered the gestational tolerogenic state, reducing the immune response against pathogens and activating the extrinsic apoptotic pathway, causing spontaneous abortion.
Assuntos
Aborto Espontâneo/microbiologia , Histocompatibilidade Materno-Fetal , Tolerância Imunológica , Placenta/microbiologia , Complicações Infecciosas na Gravidez/microbiologia , Infecções por Ureaplasma/microbiologia , Ureaplasma/patogenicidade , Aborto Espontâneo/diagnóstico , Aborto Espontâneo/imunologia , Imunidade Adaptativa , Apoptose , Proteínas Reguladoras de Apoptose/genética , Estudos de Casos e Controles , Estudos Transversais , Citocinas/genética , Feminino , Regulação da Expressão Gênica , Histocompatibilidade Materno-Fetal/genética , Interações Hospedeiro-Patógeno , Humanos , Tolerância Imunológica/genética , Imunidade Inata , Placenta/imunologia , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/genética , Complicações Infecciosas na Gravidez/imunologia , Fatores de Risco , Ureaplasma/imunologia , Infecções por Ureaplasma/diagnóstico , Infecções por Ureaplasma/genética , Infecções por Ureaplasma/imunologiaRESUMO
Transcription of non-classical major histocompatibility complex class I (MHC-I) was assessed in the bovine placenta throughout gestation. Additionally, the effect of Brucella abortus infection on expression of non-classical MHC-I was also evaluated using a chorioallantoic membrane explant model of infection. The non-classical MHC-I genes MICB and NC3 had higher levels of transcription in the intercotyledonary region when compared to the placentome, which had higher levels of transcription at the second trimester of gestation. NC1 and classical MHC-I had very low levels of transcription throughout gestation. Trophoblastic cells of B. abortus-infected chorioallantoic membrane explants had an increase in transcription of non-classical MHC-I at 4h post infection. Therefore, this study provides an analysis of non-classical MHC-I transcription at different stages of gestation and different placental tissues, and during B. abortus infection. These findings provide additional knowledge on immune regulation in placental tissues, a known immune-privileged site.