Plasmodium falciparum Infection Significantly Impairs Placental Cytokine Profile in HIV Infected Cameroonian Women

BACKGROUND:Placental cytokines play crucial roles in the establishment and maintenance of pregnancy as well as protecting the foetus from infections. Previous studies have suggested the implication of infections such as P. falciparum and HIV in the stimulation of placental cytokines. This study assessed the impact of P. falciparum on placental cytokine profiles between HIV-1 positive and negative women. MATERIALS AND METHODS:P. falciparum infection was checked in peripheral and placental blood of HIV-1 negative and positive women by the thick blood smear test. Cytokines proteins and messenger RNAs were quantified by ELISA and real time PCR, respectively. Non-parametric tests were used for statistical analyses. RESULTS:Placental and peripheral P. falciparum infections were not significantly associated with HIV-1 infection (OR: 1.4; 95% confidence interval (95%CI): 0.5-4.2; p = 0.50 and OR: 0.6; 95%CI: 0.3-1.4; p = 0.26, respectively). Conversely, placental P. falciparum parasitemia was significantly higher in the HIV-1 positive group (p = 0.04). We observed an increase of TNF-alpha mRNA median levels (p = 0.02) and a trend towards a decrease of IL-10 mRNA (p = 0.07) in placenta from HIV-1 positive women compared to the HIV negative ones leading to a median TNF-alpha/IL-10 mRNA ratio significantly higher among HIV-1 positive than among HIV-1 negative placenta (p = 0.004; 1.5 and 0.8, respectively). Significant decrease in median secreted cytokine levels were observed in placenta from HIV-1 positive women as compared to the HIV negative however these results are somewhat indicative since it appears that differences in cytokine levels (protein or mRNA) between HIV-1 positive and negative women depend greatly on P.falciparum infection. Within the HIV-1 positive group, TNF-alpha was the only cytokine significantly associated with clinical parameters linked with HIV-1 MTCT such as premature rupture of membranes, CD4 T-cell number, plasma viral load and delay of NVP intake before delivery. CONCLUSIONS:These results show that P. falciparum infection profoundly modifies the placenta cytokine environment and acts as a confounding factor, masking the impact of HIV-1 in co-infected women. This interplay between the two infections might have implications in the in utero MTCT of HIV-1 in areas where HIV-1 and P. falciparum co-circulate

Molecular monitoring of plasmodium falciparum drug susceptibility at the time of the introduction of artemisinin-based combination therapy in Yaoundé, Cameroon: Implications for the future

<p>Abstract</p> <p>Background</p> <p>Regular monitoring of the levels of anti-malarial resistance of <it>Plasmodium falciparum </it>is an essential policy to adapt therapy and improve malaria control. This monitoring can be facilitated by using molecular tools, which are easier to implement than the classical determination of the resistance phenotype. In Cameroon, chloroquine (CQ), previously the first-line therapy for uncomplicated malaria was officially withdrawn in 2002 and replaced initially by amodiaquine (AQ) monotherapy. Then, artemisinin-based combination therapy (ACT), notably artesunate-amodiaquine (AS-AQ) or artemether-lumefantrine (AL), was gradually introduced in 2004. This situation raised the question of the evolution of <it>P. falciparum </it>resistance molecular markers in Yaoundé, a highly urbanized Cameroonian city.</p> <p>Methods</p> <p>The genotype of <it>pfcrt </it>72 and 76 and <it>pfmdr1 </it>86 alleles and <it>pfmdr1 </it>copy number were determined using real-time PCR in 447 <it>P. falciparum </it>samples collected between 2005 and 2009.</p> <p>Results</p> <p>This study showed a high prevalence of parasites with mutant <it>pfcrt </it>76 (83%) and <it>pfmdr1 </it>86 (93%) codons. On the contrary, no mutations in the <it>pfcrt </it>72 codon and no samples with duplication of the <it>pfmdr1 </it>gene were observed.</p> <p>Conclusion</p> <p>The high prevalence of mutant <it>pfcrt </it>76T and <it>pfmdr1 </it>86Y alleles might be due to the choice of alternative drugs (AQ and AS-AQ) known to select such genotypes. Mutant <it>pfcrt </it>72 codon was not detected despite the prolonged use of AQ either as monotherapy or combined with artesunate. The absence of <it>pfmdr1 </it>multicopies suggests that AL would still remain efficient. The limited use of mefloquine or the predominance of mutant <it>pfmdr1 </it>86Y codon could explain the lack of <it>pfmdr1 </it>amplification. Indeed, this mutant codon is rarely associated with duplication of <it>pfmdr1 </it>gene. In Cameroon, the changes of therapeutic strategies and the simultaneous use of several formulations of ACT or other anti-malarials that are not officially recommended result in a complex selective pressure, rendering the prediction of the evolution of <it>P. falciparum </it>resistance difficult. This public health problem should lead to increased vigilance and regular monitoring.</p

Higher placental anti-inflammatory IL-10 cytokine expression in HIV-1 infected women receiving longer zidovudine prophylaxis associated with nevirapine

Placental cytokine balance may be critical for the control of mother-to-child transmission (MTCT) of HIV. We assessed whether the type and duration of antiretrovirals used for prevention of HIV-1-MTCT modified the inflammatory cytokine profile. We investigated the levels of cytokine expression in the placentas of 61 HIV-1-infected women who received zidovudine (ZDV) plus single dose nevirapine (SD-NVP) or ZDV only for prevention of MTCT. Placentas of 38 HIV-1-uninfected women were included as controls. All placentas were obtained after vaginal delivery. Levels of mRNA and cytokine expression were quantified using real-time PCR and ELISA, respectively, in placental explants and 24-hour culture supernatants and analyzed in relation to the women's characteristics and the type and duration of antiretroviral prophylaxis. HIV-1-infected and uninfected women did not show any differences in the expression of placental cytokine secretion except for a trend toward lower TNF-10 mRNA levels in HIV-1-infected women. Within the HIV-1-infected group, women who were exposed to a long duration of ZDV (>72 days) or received SD-NVP less than 5h prior to delivery, more frequently expressed detectable levels of IL-10 in their placentas (32% versus 7% (p = 0.01) and 32% versus 5% (p = 0.02), respectively). No infant was found to be HIV-1-infected. Our results showed a normalization of the placental cytokine balance in HIV-1-infected women receiving antiretroviral prophylaxis. Furthermore, the type and duration of antiretroviral prophylaxis have an impact on the placental anti-inflammatory IL-10 expression level, which may contribute to controlling HIV replication at the placental level, thus reducing MTCT of HIV-1.Fil: Pornprasert, Sakorn. Chiang Mai University; TailandiaFil: Mary, Jean-Yves. Université Paris Diderot - Paris 7; FranciaFil: Faye, Albert. Institut National de la Santé et de la Recherche Médicale; FranciaFil: Leechanachai, Pannee. Chiang Mai University; TailandiaFil: Limtrakul, Aram. Health Promotion Center Region; TailandiaFil: Rugpao, Sungwal. Chiang Mai University; TailandiaFil: Sirivatanapa, Pannee. Chiang Mai University; TailandiaFil: Gomuthbutra, Vorapin. Nakornping Hospital; TailandiaFil: Matanasaravoot, Wanmanee. Lamphun Hospital; TailandiaFil: Le Coer, Sophie. Institut National d’Etudes Démographiques; FranciaFil: Lallemant, Marc. Centre National de la Recherche Scientifique. Institut de Recherche pour le Développement; FranciaFil: Barré-Sinoussi, Françoise. Instituto Pasteur; FranciaFil: Menu, Elisabeth. Instituto Pasteur; FranciaFil: Ngo Giang Huong, Nicole. Centre National de la Recherche Scientifique. Institut de Recherche pour le Développement; FranciaFil: Ayouba, Ahidjo. Instituto Pasteur; FranciaFil: Chailert, Sanupong. Chiang Mai University; Tailandia. Instituto Pasteur; FranciaFil: Chaouat, Gérard. Institut National de la Santé et de la Recherche Médicale; FranciaFil: Derrien, Muriel. Universidad de Buenos Aires. Facultad de Medicina; ArgentinaFil: Dolcini, Guillermina Laura. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Departamento de Sanidad Animal y Medicina Preventiva. Laboratorio de Virología; Argentina. Instituto Pasteur; Francia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; ArgentinaFil: Eteki, Nicole. Hôpital Central de Yaoundé. Maternité Principale; CamerúnFil: Kfutwah, Anfumbom Jude. Instituto Pasteur; FranciaFil: Kouo, Odette. Instituto Pasteur; FranciaFil: Lemen, Brigitte. Instituto Pasteur; FranciaFil: Abal, Facundo Juan Pablo. Instituto Pasteur; FranciaFil: Nerrienet, Eric. Instituto Pasteur; FranciaFil: Njinku, Bernadette. Instituto Pasteur; FranciaFil: Scarlatti, Gabriella. Suan Dok Hospital; TailandiaFil: Tejiokem, Mathurin. Centre Pasteur du Cameroun; CamerúnFil: Téné, Gilbert. No especifíca