18 research outputs found
Surfactant protein D inhibits HIV-1 infection of target cells via interference with gp120-CD4 interaction and modulates pro-inflammatory cytokine production
© 2014 Pandit et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Surfactant Protein SP-D, a member of the collectin family, is a pattern recognition protein, secreted by mucosal epithelial cells and has an important role in innate immunity against various pathogens. In this study, we confirm that native human SP-D and a recombinant fragment of human SP-D (rhSP-D) bind to gp120 of HIV-1 and significantly inhibit viral replication in vitro in a calcium and dose-dependent manner. We show, for the first time, that SP-D and rhSP-D act as potent inhibitors of HIV-1 entry in to target cells and block the interaction between CD4 and gp120 in a dose-dependent manner. The rhSP-D-mediated inhibition of viral replication was examined using three clinical isolates of HIV-1 and three target cells: Jurkat T cells, U937 monocytic cells and PBMCs. HIV-1 induced cytokine storm in the three target cells was significantly suppressed by rhSP-D. Phosphorylation of key kinases p38, Erk1/2 and AKT, which contribute to HIV-1 induced immune activation, was significantly reduced in vitro in the presence of rhSP-D. Notably, anti-HIV-1 activity of rhSP-D was retained in the presence of biological fluids such as cervico-vaginal lavage and seminal plasma. Our study illustrates the multi-faceted role of human SPD against HIV-1 and potential of rhSP-D for immunotherapy to inhibit viral entry and immune activation in acute HIV infection. © 2014 Pandit et al.The work (Project no. 2011-16850) was supported by Medical Innovation Fund of Indian Council of Medical Research, New Delhi, India (www.icmr.nic.in/)
HIV-1 co-receptor usage:influence on mother-to-child transmission and pediatric infection
Viral CCR5 usage is not a predictive marker of mother to child transmission (MTCT) of HIV-1. CXCR4-using viral variants are little represented in pregnant women, have an increased although not significant risk of transmission and can be eventually also detected in the neonates. Genetic polymorphisms are more frequently of relevance in the child than in the mother. However, specific tissues as the placenta or the intestine, which are involved in the prevalent routes of infection in MTCT, may play an important role of selective barriers
The pathology of lethal exposure to the Riot Control Agents: Towards a forensics-based methodology for determining misuse
The aim of this is to review deaths associated with the use of Riot Control Agents (RCAs) and to assess how the presenting pathologies is such cases may better inform cause of death conclusions upon autopsy. We also sought to present which additional steps should be added to the Minnesota protocol and the European harmonization of medico-legal autopsy rules in suspected cases of deaths associated with the use of RCAs. We included 10 lethal cases in our study. In three cases, RCAs were found to be the sole cause of death, in three cases RCAs were ruled a secondary cause of death due asphyxia or asthma subsequent to exposure to RCAs and in four cases RCAs were contributory factors to death. In three cases the responsible agents were identified as Chloroacetophenone (CN), Chlorobenzylidene malononitrile (CS) and Oleoresin capsicum (OC) and in the remaining 7 cases, the agent was OC alone. As there are no specific findings in suspected cases of death associated with RCA use, establishing cause of death and whether RCAs are the sole cause or only a contributory factor will be based on the elimination of other possible causes of death. For this reason, a specifically structured autopsy is essential. This specifically structured autopsy should contain basic principles of the Minnesota Protocol and the European harmonization of medico-legal autopsy rules with the following additional steps taken: examination of clothing, eyes, and skin; examination of pharyngeal, tracheobronchial, and eusophegeal mucosas; and a thorough recording of the steps taken by the party conducting the arrest, including other possible causes of in-custody death, as well as a detailed medical history of the deceased. © 2014 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved
Harmonization of European Laboratory Response Networks by Implementing CWA 15793: Use of a Gap Analysis and an “Insider” Exercise as Tools
Transmitted HIV-1 variants in HIV infected mother-child pairs carrying different subtypes
Coreceptor change appears after immune deficiency is established in children infected with different HIV-1 subtypes
Change of HIV-1 coreceptor use has been connected to progression of disease in children infected with HIV-1, presumably subtype B. It has not been possible to discern whether the appearance of new viral phenotypes precedes disease development or comes as a consequence of it. We studied the evolution of coreceptor use in HIV-1 isolates from 24 vertically infected children. Their clinical, virological, and immunological status was recorded and the env V3 subtype was determined by DNA sequencing. Coreceptor use was tested on human cell lines, expressing CD4 together with CCR5, CXCR4, and other chemokine receptors. The children carried five different env subtypes (nine A, five B, four C, three D, and one G) and one circulating recombinant form, CRF01_AE (n=2). Of the 143 isolates, 86 originated from peripheral blood mononuclear cells (PBMCs) and 57 originated from plasma, received at 90 time points. In 52 of 54 paired plasma and PBMC isolates the coreceptor use was concordant. All 74 isolates obtained at 41 time points during the first year of life used CCR5. A change from use of CCR5 to use of CXCR4 occurred in four children infected with subtype A, D, or CRF01_AE after they had reached 1.5 to 5.8 years of age. There was a significant association with decreased CD4 1 cell levels and severity of disease but, interestingly, the coreceptor change appeared months or even years after the beginning of the immunological deterioration. Thus CXCR4-using virus may emerge as a possible consequence of immune deficiency. The results provide new insights into AIDS development in children
The X4 phenotype of HIV type 1 evolves from R5 in two children of mothers, carrying X4, and is not linked to transmission
Previously, we found that emergence of the X4 viral phenotype in HIV-1-infected children was related to the presence of X4 in their mothers (C. H. Casper et al., J Infect Dis 2002; 186: 914-921). Here, we investigated the origin of the X4 phenotype in the child, analyzing two mother-child pairs (Ma-Ca, Mb-Cb) where the mothers carried X4 and their children developed X4 after an initial presence of R5. We used nested polymerase chain reaction of the env V3 region to generate 203 HIV-1 clones for sequencing (Ma, n = 44; Ca, n = 73; Mb, n = 61; Cb, n = 25) from DNA of peripheral blood mononuclear cell (PBMC) lysates, altogether 167 clones, or from cDNA of plasma RNA, 36 clones. PBMC and plasma isolate sequences from each time point enabled us to assign the probable phenotype to clone sequences in a phylogenetic tree. The transmission and evolution were reconstructed using the maximum likelihood method. In mother-child pair Ma-Ca, one maternal R5 isolate clustered with the child's R5 sequences, at the earliest time when R5 was isolated in the child, confirming this as a likely source of the transmitted R5 phenotype. At age 3, an X4 population was present in the child that had evolved from the child's own R5-associated population, clearly distinct from the maternal X4 sequences. The second mother-child pair (Mb-Cb) displayed a similar pattern. Amino acid substitution patterns corroborated the conclusions from the phylogenetic tree. Thus, in both children, the X4 virus developed from their own R5 population, and was not caused by transmission of X4
Link between the X4 phenotype in human immunodeficiency virus type 1-infected mothers and their children, despite the early presence of R5 in the child
Coreceptor use was determined for human immunodeficiency virus type 1 (HIV-1) isolates of various subtypes from 11 women during pregnancy and their infected children. Isolates from peripheral blood mononuclear cells (n = 79) and from plasma (n = 59) were available. The clinical and immunological stages of HIV-1 infection were recorded. Coreceptor use was tested on human cell lines expressing CD4 and different chemokine receptors. The R5 virus predominated, and only 9 isolates from 2 mothers used CXC chemokine receptor 4. All children carried the R5 virus at the time of diagnosis of HIV-1 infection. In 2 children of mothers carrying the X4 virus, the virus switched from R5 to X4 or to R5X4 by age 18 months (child no. 9) and age 48 months (child no. 10), whereas no children followed up to a similar age whose mothers were carrying the R5 virus experienced such a switch (). This points to a link between the P = .048 presence of X4 virus in the mother and the emergence of X4 virus in her child