Rosa Maria S. Aveiro Ruocco

TLR7/TLR8 Activation Restores Defective Cytokine Secretion by Myeloid Dendritic Cells but Not by Plasmacytoid Dendritic Cells in HIV-Infected Pregnant Women and Newborns.

Mother-to-child transmission (MTCT) of HIV-1 has been significantly reduced with the use of antiretroviral therapies, resulting in an increased number of HIV-exposed uninfected infants. The consequences of HIV infection on the innate immune system of both mother-newborn are not well understood. In this study, we analyzed peripheral blood and umbilical cord blood (CB) collected from HIV-1-infected and uninfected pregnant women. We measured TNF-α, IL-10 and IFN-α secretion after the stimulation of the cells with agonists of both extracellular Toll-like receptors (TLRs) (TLR2, TLR4 and TLR5) and intracellular TLRs (TLR7, TLR7/8 and TLR9). Moreover, as an indicator of the innate immune response, we evaluated the responsiveness of myeloid dendritic cells (mDCs) and plasmacytoid DCs (pDCs) to TLRs that are associated with the antiviral response. Our results showed that peripheral blood mononuclear cells (PBMCs) from HIV-1-infected mothers and CB were defective in TNF-α production after activation by TLR2, TLR5, TLR3 and TLR7. However, the TNF-α response was preserved after TLR7/8 (CL097) stimulation, mainly in the neonatal cells. Furthermore, only CL097 activation was able to induce IL-10 and IFN-α secretion in both maternal and CB cells in the infected group. An increase in IFN-α secretion was observed in CL097-treated CB from HIV-infected mothers compared with control mothers. The effectiveness of CL097 stimulation was confirmed by observation of similar mRNA levels of interferon regulatory factor-7 (IRF-7), IFN-α and TNF-α in PBMCs of both groups. The function of both mDCs and pDCs was markedly compromised in the HIV-infected group, and although TLR7/TLR8 activation overcame the impairment in TNF-α secretion by mDCs, such stimulation was unable to reverse the dysfunctional type I IFN response by pDCs in the HIV-infected samples. Our findings highlight the dysfunction of innate immunity in HIV-infected mother-newborn pairs. The activation of the TLR7/8 pathway could function as an adjuvant to improve maternal-neonatal innate immunity.

Upregulation of Innate Antiviral Restricting Factor Expression in the Cord Blood and Decidual Tissue of HIV-Infected Mothers

Programs for the prevention of mother-to-child transmission of HIV have reduced the transmission rate of perinatal HIV infection and have thereby increased the number of HIV-exposed uninfected (HEU) infants. Natural immunity to HIV-1 infection in both mothers and newborns needs to be further explored. In this study, we compared the expression of antiviral restricting factors in HIV-infected pregnant mothers treated with antiretroviral therapy (ART) in pregnancy (n=23) and in cord blood (CB) (n=16), placental tissues (n=10-13) and colostrum (n=5-6) samples and compared them to expression in samples from uninfected (UN) pregnant mothers (n=21). Mononuclear cells (MNCs) were prepared from maternal and CB samples following deliveries by cesarean section. Maternal (decidua) and fetal (chorionic villus) placental tissues were obtained, and colostrum was collected 24 h after delivery. The mRNA and protein expression levels of antiviral factors were then evaluated. We observed a significant increase in the mRNA expression levels of antiviral factors in MNCs from HIV-infected mothers and CB, including the apolipoprotein B mRNA-editing enzyme 3G (A3G), A3F, tripartite motif family-5α (TRIM-5α), TRIM-22, myxovirus resistance protein A (MxA), stimulator of interferon (IFN) genes (STING) and IFN-β, compared with the levels detected in uninfected (UN) mother-CB pairs. Moreover, A3G transcript and protein levels and α-defensin transcript levels were decreased in the decidua of HIV-infected mothers. Decreased TRIM-5α protein levels in the villi and increased STING mRNA expression in both placental tissues were also observed in HIV-infected mothers compared with uninfected (UN) mothers. Additionally, colostrum cells from infected mothers showed increased tetherin and IFN-β mRNA levels and CXCL9 protein levels. The data presented here indicate that antiviral restricting factor expression can be induced in utero in HIV-infected mothers. Future studies are warranted to determine whether this upregulation of antiviral factors during the perinatal period has a protective effect against HIV-1 infection.

Avaliação ultra-sonográfica, ecocardiográfica fetal e resultados perinatais em gestantes portadoras do HIV em uso de terapia anti-retroviral

PuRPOse : to evaluate fetal structural and/or functional abnormalities by ultrasound examination and fetal echocardiography, in pregnant women positive for human immunodeficiency virus (HIV). MethOds: we analyzed prospectively 109 HIV positive pregnant women under antiretroviral therapy (Study Group) and 200 low risk pregnant patients (Control Group). All of them were submitted to ultrasound scan and fetal and neonatal echocardiography once a month. The amniotic fluid volume, fetal growth, fetal structural and functional alteration and the perinatal outcome were evaluated. Results: there were eight (7.3%) cases of fetal structural abnormality in the Study Group and two (1%) in the Control Group (p=0.616). There were four cases of congenital heart disease and four cases of hydronephrosis in the Study Group, with statistic significance (p=0.015) for the cardiac abnormalities. There were eight cases (7.3%) of oligohydramnios and 11 cases (10%) of polyhydramnios in the Study Group against two cases (1%) of oligohydramnios and none of polyhydramnios in the Control Group (p=0.004 and p<0.001). Eleven (10%) newborn babies were too small for their gestation age in the Study Group, against three (2.7%) in the Control Group (p=0,002). The incidence of preterm delivery was 8.7 and 2.5% in the Study and Control Groups respectively (p=0.041). It was observed six cases (5.5%) of fetal death in the Study Group and none in the Control Group (p=0.002). COnClusiOns: in the present study, we have observed higher prevalence of amniotic fluid volume and congenital heart abnormalities in the Study Group as compared to the Control Group. Statistical significance was found in both situations. The high fetal death rate found in the Study Group was probably due to fetal malformation, whereas the high prematurity rate and the prevalence of small size for the gestational age of the newborn babies were probably related to antiretroviral therapy, smoking and drug abuse. t rabalho realizado na Clinica Obstetrica do hospital das Clinicas da Faculdade de Medicina da universidade de sao Paulo –usP – sao Paulo (sP), brasil. 1

Fatores maternos e resultados perinatais no descolamento prematuro da placenta: comparação entre dois períodos

PURPOSE: to compare the maternal factors, clinical aspects and perinatal results in placental abruption during two periods. METHODS: retrospective analysis of placental abruption cases that occurred from January 1, 1994 through December 31, 1997 (period 94-97), and from April 4, 2001 through March 3, 2005 (period 01-05), in singleton delivery with birthweight higher than 500 g and after 20 weeks of gestation. The following factors were analyzed: maternal age, previous obstetric history, prenatal care, premature rupture of membranes, obstetric and/or clinical intercurrent events, vaginal bleeding, uterine tonus, fetal anomaly, mode of delivery, hemoamnion and maternal complication (hysterectomy, uterine atony, disseminated intravascular coagulation, acute renal failure, and maternal death), and the perinatal results. RESULTS: the rate of placental abruption was 0.78% (60 cases) in the period 94-97 (n=7692 deliveries), and 0.59% (51 cases) in the period 01-05 (n=8644 deliveries), without significant difference. A significant difference was observed between the periods 94-97 and 01-05 regarding mean number of previous gestations (3.5±2.4 and 2.6±1.8, p=0.04), patients without prenatal care (13.3 and 2.0%, p=0.03) and maternal intercurrences (38.3 and 64.7%, p=0.01). No significant difference was observed related to vaginal bleeding, tonus abnormalities and perinatal results, between the periods, but a higher proportion of hemoamnion in 94-97 was found when compared to 01-05 (28.3 and 11.8%, p=0.03). CONCLUSIONS: in spite of obstetrical advances, maternal complications and perinatal results were similar in the analyzed periods. The severity and the unexpected results emphasize the importance of prevention and adequate control of associated factors, when this pathology is approached.