Unfortunately, the vaccine mediated an increased risk of symptomatic dengue in vaccine recipients who were seronegative at baseline [7]. == The results demonstrate that mAbs can neutralize Lactacystin infectious DENV derived from infected human cells, in the matrix of human blood. Coupled with previous evidence of their ability to prevent DENV contamination of mammalian cells, such mAbs could be considered attractive antibody classes to elicit with dengue vaccines, or alternatively, for concern as therapeutic candidates. == Author summary == Dengue is the most prevalent arboviral disease affecting humans. There are no therapeutics for the disease. We developed a novel Lactacystin computer virus neutralization assay, employingAe.aegyptimosquitoes and viremic blood from dengue patients, to examine the virus-neutralizing potency of 12 human-derived monoclonal antibodies (mAbs) that had previously been shown to neutralize DENV in cell-culture systems. Five of the twelve mAbs failed to block dengue computer virus infections of mosquitoes using our assay. The remaining seven mAbs neutralized at least one serotype of dengue computer virus. The results demonstrate that some mAbs were functional and potently neutralized DENV in the complex matrix of viremic human blood. These findings advance the understanding of the types of antibodies that would be desirable to elicit using a dengue vaccine or to apply for acute therapy. == Introduction == DENV infections are highly prevalent in the tropical and subtropical world [1]. Following a primary DENV contamination it is widely accepted that an individual develops long-lived clinical immunity to the infecting serotype but not to other serotypes. DENV contamination can be subclinical, or result in a febrile syndrome that in a small percentage of patients is usually complicated by vascular leakage, thrombocytopenia and altered hemostasis, usually between the fourth and sixth days of illness [2]. The risk of clinically important complications is usually higher when an individual is infected for a second time with a different DENV serotype from the first [3]. In this situation, cross-reactive antibodies are hypothesized to enhance the viral contamination [4]. Antibodies are central to the concepts of dengue pathogenesis and naturally-acquired or vaccine-elicited immunity. For example, the induction of computer virus neutralizing antibodies by vaccination is the minimum goal of most candidate dengue vaccines [5]. The only-licensed dengue vaccine, Dengvaxia, was developed on the basis that it could elicit antibodies that neutralized all four serotypes of DENVin vitro[6]. Unfortunately, the vaccine mediated an increased risk of symptomatic dengue in vaccine recipients who were seronegative at baseline [7]. Despite the agreed centrality of antibodies to dengue pathogenesis, laboratory correlates of immunity (or disease enhancement risk) have not been tightly defined or standardized. There is; however, a general consensus that increasingly higher serum concentrations of neutralizing antibodies are associated with reduced risk of dengue [8,9]. The ability to generate and characterize human mAbs from dengue immune donors has provided insights into the type of antibodies that might be desirable to elicit via immunization, or alternatively, to use as therapeutic brokers. Most prominent are those human mAbs identified as being able to neutralize DENV infectivity for mammalian cells [1016]. Some of these neutralizing mAbs bind to viral envelope proteins that have quaternary structures [1720]. Here we developed aviremicbloodneutralizationassay (ViBNA), in which blood from dengue patients was spiked with mAbs, and was then used to feedAe.aegyptimosquitoes. We used this assay to characterize a Rabbit polyclonal to ERMAP panel of 12 anti-DENV human mAbs with different serotype specificities and epitope binding characteristics. We more deeply characterized a small panel of mAbs for their effective concentrations (EC50) that neutralized DENV. Collectively, the results define the potency of these mAbs in the complex matrix of human blood, and against populations of DENV that have replicated in human tissues, which can inform dengue vaccine development and therapeutic approaches. == Methods == == Viremic blood neutralization assay (ViBNA) == Viremic blood was drawn from NS1-positive dengue patients and spiked with various concentrations of individual mAbs. The blood-antibody mixture was incubated at 37C for 30 minutes to allow antibodies to bind to DENV. Controls Lactacystin were prepared in parallel; the positive control for blocking DENV transmission was Lactacystin inactivated hyper-immune plasma, created by pooling early convalescent plasma samples from 119 dengue cases. Lactacystin The unfavorable control was.