Pre-clinical development as microbicide of zinc tetra-ascorbo-camphorate, a novel terpenoid derivative: Potent in vitro inhibitory activity against both R5- and X4-tropic HIV-1 strains without significant in vivo mucosal toxicity

<p>Abstract</p> <p>Background</p> <p>Terpenoid derivatives originating from many plants species, are interesting compounds with numerous biological effects, such as anti-HIV-1 activity. The zinc tetra-ascorbo-camphorate complex (or "C14"), a new monoterpenoid derivative was evaluated in vitro for its anti-HIV-1 activity on both R5- and X4-HIV-1 infection of primary target cells (macrophages, dendritic cells and T cells) and on HIV-1 transfer from dendritic cells to T cells.</p> <p>Results</p> <p>The toxicity study was carried out in vitro and also with the New Zealand White rabbit vaginal irritation model. C14 was found to be no cytotoxic at high concentrations (CC50 > 10 μM) and showed to be a potential HIV-1 inhibitor of infection of all the primary cells tested (EC50 = 1 μM). No significant changes could be observed in cervicovaginal tissue of rabbit exposed during 10 consecutive days to formulations containing up to 20 μM of C14.</p> <p>Conclusion</p> <p>Overall, these preclinical studies suggest that zinc tetra-ascorbo-camphorate derivative is suitable for further testing as a candidate microbicide to prevent male-to-female heterosexual acquisition of HIV-1.</p

HSV-2- and HIV-1- permissive cell lines co-infected by HSV-2 and HIV-1 co-replicate HSV-2 and HIV-1 without production of HSV-2/HIV-1 pseudotype particles

BACKGROUND: Herpes simplex virus type 2 (HSV-2) is a major cofactor of human immunodeficiency virus type 1 (HIV-1) sexual acquisition and transmission. In the present study, we investigated whether HIV-1 and HSV-2 may interact at the cellular level by forming HIV-1 hybrid virions pseudotyped with HSV-2 envelope glycoproteins, as was previously reported for HSV type 1. METHODS: We evaluated in vitro the production of HSV-2/HIV-1 pseudotypes in mononuclear CEM cells and epithelial HT29 and P4P cells. We analyzed the incorporation into the HIV-1 membrane of HSV-2 gB and gD, two major HSV-2 glycoproteins required for HSV-2 fusion with the cell membrane, in co-infected cells and in HIV-1-infected P4P cells transfected by plasmids coding for gB or gD. RESULTS: We show that HSV-2 and HIV-1 co-replicated in dually infected cells, and gB and gD were co-localized with gp160. However, HIV-1 particles, produced in HIV-1-infected cells expressing gB or gD after transfection or HSV-2 superinfection, did not incorporate either gB or gD in the viral membrane, and did not have the capacity to infect cells normally non-permissive for HIV-1, such as epithelial cells. CONCLUSION: Our results do not support the hypothesis of HSV-2/HIV-1 pseudotype formation and involvement in the synergistic genital interactions between HIV-1 and HSV-2

Neutralizing monoclonal antibodies to human immunodeficiency virus type 1 do not inhibit viral transcytosis through mucosal epithelial cells

AbstractHIV-1 transcytosis has been proposed as a potential mechanism allowing the virus to cross the epithelium during mucosal transmission. Epitopes of the HIV-1 envelope involved in this process have not been identified yet. Here, we assessed a large panel of HIV neutralizing antibodies recognizing well-characterized epitopes of the HIV-1 envelope for their ability to block HIV-1 transcytosis across a confluent epithelial monolayer.We found that all of the 13 HIV-1-specific monoclonal antibodies tested in the present study, including the three broadly neutralizing antibodies 2F5, 2G12 and IgG1b12, lacked the ability to inhibit transcytosis of cell-free and cell-associated R5- as X4-tropic HIV-1 across a tight and polarized monolayer of HEC-1 epithelial cells. In contrast, anti-gp160 polyclonal antibodies purified from serum or breast milk of HIV-1-infected individuals potently inhibited HIV-1 transcytosis. Furthermore, polymeric S-IgA exhibited similar ability to inhibit transcytosis compared to IgG despite their lower anti-gp160 specific activity. Together, these results demonstrate that the major neutralizing envelope epitopes of HIV-1 are not involved in HIV-1 transcytosis, and suggest that surface agglutination of virus particles may participate to the blocking effect observed with both polyclonal and polymeric anti-gp160 immunoglobulins

Differential activity of candidate microbicides against early steps of HIV-1 infection upon complement virus opsonization

ABSTRACT: BACKGROUND: HIV-1 in genital secretions may be opsonized by several molecules including complement components. Opsonized HIV-1 by complement enhances the infection of various mucosal target cells, such as dendritic cells (DC) and epithelial cells. RESULTS: We herein evaluated the effect of HIV-1 complement opsonization on microbicide candidates activity, by using three in vitro mucosal models: CCR5-tropic HIV-1JR-CSF transcytosis through epithelial cells, HIV-1JR-CSF attachment on immature monocyte-derived dendritic cells (iMDDC), and infectivity of iMDDC by CCR5-tropic HIV-1BaL and CXCR4-tropic HIV-1NDK. A panel of 10 microbicide candidates [T20, CADA, lectines HHA & GNA, PVAS, human lactoferrin, and monoclonal antibodies IgG1B12, 12G5, 2G12 and 2F5], were investigated using cell-free unopsonized or opsonized HIV-1 by complements. Only HHA and PVAS were able to inhibit HIV trancytosis. Upon opsonization, transcytosis was affected only by HHA, HIV-1 adsorption on iMDDC by four molecules (lactoferrin, IgG1B12, IgG2G5, IgG2G12), and replication in iMDDC of HIV-1BaL by five molecules (lactoferrin, CADA, T20, IgG1B12, IgG2F5) and of HIV-1NDK by two molecules (lactoferrin, IgG12G5). CONCLUSION: These observations demonstrate that HIV-1 opsonization by complements may modulate in vitro the efficiency of candidate microbicides to inhibit HIV-1 infection of mucosal target cells, as well as its crossing through mucos

Analytical Performances of Human Immunodeficiency Virus Type 1 RNA-Based Amplix® Real-Time PCR Platform for HIV-1 RNA Quantification

Objectives. We evaluated the performances of Amplix real-time PCR platform developed by Biosynex (Strasbourg, France), combining automated station extraction (Amplix station 16 Dx) and real-time PCR (Amplix NG), for quantifying plasma HIV-1 RNA by lyophilized HIV-1 RNA-based Amplix reagents targeting gag and LTR, using samples from HIV-1-infected adults from Central African Republic. Results. Amplix real-time PCR assay showed low limit of detection (28 copies/mL), across wide dynamic range (1.4–10 log copies/mL), 100% sensitivity and 99% specificity, high reproducibility, and accuracy with mean bias < 5%. The assay showed excellent correlations and concordance of 95.3% with the reference HIV-1 RNA load assay (Roche), with mean absolute bias of +0.097 log copies/mL by Bland-Altman analysis. The assay was able to detect and quantify the most prevalent HIV-1 subtype strains and the majority of non-B subtypes, CRFs of HIV-1 group M, and HIV-1 groups N and O circulating in Central Africa. The Amplix assay showed 100% sensitivity and 99.6% specificity to diagnose virological failure in clinical samples from antiretroviral drug-experienced patients. Conclusions. The HIV-1 RNA-based Amplix real-time PCR platform constitutes sensitive and reliable system for clinical monitoring of HIV-1 RNA load in HIV-1-infected children and adults, particularly adapted to intermediate laboratory facilities in sub-Saharan Africa

Auto-test sur sang prélevé au bout du doigt pour la détection d'HIV, HBV et HCV utilisant un test immunochromatographique multiplex: étude pilote en Afrique subsaharienne

peer reviewedBACKGROUND: The burden of HIV, HBV, and HCV infections remains disproportionately high in sub-Saharan Africa, with high rates of co-infections. Multiplex rapid diagnostic tests for HIV, HBV and HCV serological testing with high analytical performances may improve the "cascade of screening" and quite possibly the linkage-to-care with reduced cost. Based on our previous field experience of HIV self-testing, we herein aimed at evaluating the practicability and acceptability of a prototype finger-stick whole-blood Triplex HIV/HCV/HBsAg self-test as a simultaneous serological screening tool for HIV, HBV, and HCV in the Democratic Republic of the Congo (DRC). METHODS: A cross-sectional multicentric study consisting of face-to-face, paper-based, and semi-structured questionnaires with a home-based and facility-based recruitment of untrained adult volunteers at risk of HIV, HBV, and HCV infections recruited from the general public was conducted in 2020 in urban and rural areas in the DRC. The practicability of the Triplex self-test was assessed by 3 substudies on the observation of self-test manipulation including the understanding of the instructions for use (IFU), on the interpretation of Triplex self-test results and on its acceptability. RESULTS: A total of 251 volunteers (mean age, 28 years; range, 18-49; 154 males) were included, from urban [160 (63.7%)] and rural [91 (36.3%)] areas. Overall, 242 (96.4%) participants performed the Triplex self-test and succeeded in obtaining a valid test result with an overall usability index of 89.2%. The correct use of the Triplex self-test was higher in urban areas than rural areas (51.2% versus 16.5%; aOR: 6.9). The use of video IFU in addition to paper-based IFU increased the correct manipulation and interpretation of the Triplex self-test. A total of 197 (78.5%) participants correctly interpreted the Triplex self-test results, whereas 54 (21.5%) misinterpreted their results, mainly the positive test results harboring low-intensity band (30/251; 12.0%), and preferentially the HBsAg band (12/44; 27.3%). The rates of acceptability of reuse, distribution of the Triplex self-test to third parties (partner, friend, or family member), linkage to the health care facility for confirmation of results and treatment, and confidence in the self-test results were very high, especially among participants from urban areas. CONCLUSIONS: This pilot study shows evidence for the first time in sub-Saharan Africa on good practicability and high acceptability of a prototype Triplex HIV/HCV/HBsAg self-test for simultaneous diagnosis of three highly prevalent chronic viral infections, providing the rational basis of using self-test harboring four bands of interest, i.e. the control, HIV, HCV, and HBsAg bands. The relatively frequent misinterpretation of the Triplex self-test points however the necessity to improve the delivery of this prototype Triplex self-test probably in a supervised setting. Finally, these observations lay the foundations for the potential large-scale use of the Triplex self-test in populations living in sub-Saharan Africa at high risk for HIV, HBV, and HCV infections

Diagnosis of genital herpes simplex virus infection in the clinical laboratory.

International audienceSince the type of herpes simplex virus (HSV) infection affects prognosis and subsequent counseling, type-specific testing to distinguish HSV-1 from HSV-2 is always recommended. Although PCR has been the diagnostic standard method for HSV infections of the central nervous system, until now viral culture has been the test of choice for HSV genital infection. However, HSV PCR, with its consistently and substantially higher rate of HSV detection, could replace viral culture as the gold standard for the diagnosis of genital herpes in people with active mucocutaneous lesions, regardless of anatomic location or viral type. Alternatively, antigen detection-an immunofluorescence test or enzyme immunoassay from samples from symptomatic patients--could be employed, but HSV type determination is of importance. Type-specific serology based on glycoprotein G should be used for detecting asymptomatic individuals but widespread screening for HSV antibodies is not recommended. In conclusion, rapid and accurate laboratory diagnosis of HSV is now become a necessity, given the difficulty in making the clinical diagnosis of HSV, the growing worldwide prevalence of genital herpes and the availability of effective antiviral therapy

Calcium phosphate: a substitute for aluminum adjuvants?

Introduction: Calcium phosphate was used as an adjuvant in France in diphtheria, tetanus, pertussis and poliomyelitis vaccines. It was later completely substituted by alum salts in the late 80’s, but it still remains as an approved adjuvant for the World Health Organization for human vaccination. Area covered: Thus, calcium phosphate is now considered as one of the substances that could replace alum salts in vaccines. The aim of this paper is to draw a review of existing data on calcium phosphate as an adjuvant in order to bring out the strengths and weaknesses for its use on a large scale. Expert commentary: Calcium phosphate is a compound naturally present in the organism, safe and already used in human vaccination. Beyond comparisons with the other adjuvants, calcium phosphate represents a good candidate to replace or to complete alum salts as a vaccine adjuvant