The predicted extracellular domain of the CD2v protein of African swine fever virus (ASFV) shares significant similarity to that of the CD2 protein in T cells but has a unique cytoplasmic domain of unknown function. Here we have shown that CD2v is expressed as a glycoprotein of approximately 105 kDa in ASFV-infected cells. In the absence of an extracellular ligand, the majority of CD2v appears to localize to perinuclear membrane compartments. Furthermore, we have shown using the yeast two-hybrid system and by direct binding studies that the cytoplasmic tail of CD2v binds to the cytoplasmic adaptor protein SH3P7 (mAbp1, HIP55), which has been reported to be involved in diverse cellular functions such as vesicle transport and signal transduction. A cDNA clone encoding a variant form of SH3P7 could also be identified and was found to be expressed in a wide range of porcine tissues. Deletion mutagenesis identified proline-rich repeats of sequence PPPKPC in the ASFV CD2v protein to be necessary and sufficient for binding to the SH3 domain of SH3P7. In ASFV-infected cells, CD2v and SH3P7 co-localized in areas surrounding the perinuclear virus factories. These areas also stained with an antibody that recognizes a Golgi network protein, indicating that they contained membranes derived from the Golgi network. Our data provide a first molecular basis for the understanding of the immunomodulatory functions of CD2v in ASFV-infected animals.

the Flaviviridae virus family was named after the Yellow-fever virus, and the latin term flavi means "of golden color". Dengue, caused by Dengue virus (DENV), is one of the most important infectious diseases worldwide. A sensitive and differential diagnosis is crucial for patient management, especially due to the occurrence of serological cross-reactivity to other co-circulating flaviviruses. This became particularly important with the emergence of Zika virus (ZIKV) in areas were DENV seroprevalence was already high. We developed a sensitive and specific diagnostic test based on gold nanorods (GNR) functionalized with DENV proteins as nanosensors. These were able to detect as little as one picogram of anti-DENV monoclonal antibodies and highly diluted DENV-positive human sera. The nanosensors could differentiate DENV-positive sera from other flavivirus-infected patients, including ZIKV, and were even able to distinguish which DENV serotype infected individual patients. Readouts are obtained in ELISA-plate spectrophotometers without the need of specific devices. Dengue is an arboviral infection that is endemic in countries of Asia, Oceania, the Americas, Africa, and the Caribbean. The US Centers for Disease Control and Prevention (CDC) estimates that about 40% of the world's population live in regions where the risk of dengue transmission is high 1. The last comprehensive study on global dengue burden has put the number of yearly infections in about 390 million 2 and even though the study was published a few years ago the World Health Organization (WHO) still consider those as the most likely actual numbers 3,4. Dengue virus (DENV), the pathogen that causes dengue fever and other manifestations, is classified as part of the Flavivirus genus within the Flaviviridae family. The family was named after the Yellow fever virus (YFV) and the Latin particle Flavi means "of golden color"-a reference to the onset of jaundice observed in YFV-infected patients. Flaviviruses are enveloped viruses whose genome encodes just one open reading frame (ORF) that codifies a single polyprotein. During the virus replication cycle the polyprotein is cleaved in three structural and seven nonstructural polypeptides by virus-coded or cell proteases 5. The DENV Envelope protein (DENV E) is an immunodominant polypeptide that is inserted into the virus envelope and exposed on the virus surface, mediating the adsorption to host cells and membrane fusion upon cell entry 6. There are four known DENV serotypes which are genetically and antigenically distinct, and each one is able to cause clinical manifestations ranging from asymptomatic infections to severe disease or even death 7,8. DENV infections by any serotype induce protective immune responses against subsequent infections with the same serotype, whereas heterotypic secondary infections may lead to exacerbated viral multiplication and the development of severe disease 9-11. The Zika virus (ZIKV) (a closely related flavivirus

Vaccines are the most cost-effective intervention in the management of infectious disease. Much of what we perceive as quality of life is related to a good health status and disease absence, for which vaccines are substantially responsible. Nonetheless, there are many infectious diseases for which no vaccine solution is available. That could be due to limitations of the classic approaches to vaccine development, including inactivated, subunit and attenuated vaccines. Nanostructured immunogens belong to a class of nonclassic vaccines in which nanostructures are loaded with antigen-related molecules. Here, we briefly review important features of the nanostructured vaccines – mainly those based in carbon nanotubes and gold nanorods – and discuss their use to prevent infectious diseases, especially those caused by viruses.

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