Spot the Difference-Development of a Syndrome Based Protein Microarray for Specific Serological Detection of Multiple Flavivirus Infections in Travelers

Background The family Flaviviridae, genus Flavivirus, holds many of the world’s most prevalent arboviral diseases that are also considered the most important travel related arboviral infections. In most cases, flavivirus diagnosis in travelers is primarily based on serology as viremia is often low and typically has already been reduced to undetectable levels when symptoms set in and patients seek medical attention. Serological differentiation between flaviviruses and the false-positive results caused by vaccination and cross-reactivity among the different species, are problematic for surveillance and diagnostics of flaviviruses. Their partially overlapping geographic distribution and symptoms, combined with increase in travel, and preexisting antibodies due to flavivirus vaccinations, expand the need for rapid and reliable multiplex diagnostic tests to supplement currently used methods. Goal We describe the development of a multiplex serological protein microarray using recombinant NS1 proteins for detection of medically important viruses within the genus Flavivirus. Sera from clinical flavivirus patients were used for primary development of the protein microarray. Results Results show a high IgG and IgM sensitivity and specificity for individual NS1 antigens, and limited cross reactivity, even within serocomplexes. In addition, the serology based on this array allows for discrimination between infection and vaccination response for JEV vaccine, and no cross-reactivity with TBEV and YFV vaccine induced antibodies when testing for antibodies to other flaviviruses. Conclusion Based on these data, multiplex NS1-based protein microarray is a promising tool for surveillance and diagnosis of flaviviruses.

Two serological approaches for detection of antibodies to SARS-CoV-2 in different scenarios: a screening tool and a point-of-care test

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected more than 8 million people worldwide, becoming a pandemic. Detecting antibodies against SARS-CoV-2 is of utmost importance and a good indicator of exposure and circulation of the virus within the general population. Two serological tools based on a double recognition assay [enzyme-linked immunosorbent assay (DR-ELISA) and lateral flow assay (DR-LFA)] to detect total antibodies to SARS-CoV-2 have been developed based on the recombinant nucleocapsid protein. A total of 1065 serum samples, including positive for COVID-19 and negative samples from healthy donors or infected with other respiratory pathogens, were analyzed. The results showed values of sensitivity between 91.2% and 100%, and specificity of 100% and 98.2% for DR-LFA and DR-ELISA, respectively. No cross-reactivity against seasonal coronavirus (HCoV-NL63, HCoV-229E, HCoV-HKU1, HCoV-OC43) was found. These results demonstrate the importance of serology as a complementary tool to polymerase chain reaction for follow-up of recovered patients and identification of asymptomatic individuals

Spot the Difference—Development of a Syndrome Based Protein Microarray for Specific Serological Detection of Multiple Flavivirus Infections in Travelers

The family Flaviviridae, genus Flavivirus, holds many of the world’s most prevalent arboviral diseases that are also considered the most important travel related arboviral infections. In most cases, flavivirus diagnosis in travelers is primarily based on serology as viremia is often low and typically has already been reduced to undetectable levels when symptoms set in and patients seek medical attention. Serological differentiation between flaviviruses and the false-positive results caused by vaccination and cross-reactivity among the different species, are problematic for surveillance and diagnostics of flaviviruses. Their partially overlapping geographic distribution and symptoms, combined with increase in travel, and preexisting antibodies due to flavivirus vaccinations, expand the need for rapid and reliable multiplex diagnostic tests to supplement currently used methods. We describe the development of a multiplex serological protein microarray using recombinant NS1 proteins for detection of medically important viruses within the genus Flavivirus. Sera from clinical flavivirus patients were used for primary development of the protein microarray. Results show a high IgG and IgM sensitivity and specificity for individual NS1 antigens, and limited cross reactivity, even within serocomplexes. In addition, the serology based on this array allows for discrimination between infection and vaccination response for JEV vaccine, and no cross-reactivity with TBEV and YFV vaccine induced antibodies when testing for antibodies to other flaviviruses Based on these data, multiplex NS1-based protein microarray is a promising tool for surveillance and diagnosis of flaviviruses

Common Variation in the PIN1 Locus Increases the Genetic Risk to Suffer from Sertoli Cell-Only Syndrome

Funding Information: Funding: This work was supported by the Plan Andaluz de Investigación, Desarrollo e Innovación (PAIDI 2020) (ref. PY20_00212, P20_00583), and the Spanish Ministry of Economy and Competitiveness through the Spanish National Plan for Scientific and Technical Research and Innovation (ref. SAF2016–78722-R, PID2020–120157RB-I00) and the Proyectos I + D + i del Programa Operativo FEDER 2020 (ref. B-CTS-584-UGR20, B-CTS-260-UGR20). FDC was supported by the “Ramón y Cajal” program (ref. RYC-2014–16458), and LBC was supported by the Spanish Ministry of Economy and Competitiveness through the “Juan de la Cierva Incorporación” program (Grant ref. IJC2018– 038026-I, funded by MCIN/AEI/10.13039/501100011033), all of them including FEDER funds. AGJ was funded by MCIN/AEI/10.13039/501100011033 and FSE “El FSE invierte en tu futuro”(grant ref. FPU20/02926). SGM was funded by a previously mentioned project (ref. PY20_00212). IPATIMUP integrates the i3S Research Unit, which is partially supported by the Portuguese Foundation for Science and Technology (FCT), financed by the European Social Funds (COMPETE-FEDER) and National Funds (projects PEstC/SAU/LA0003/2013 and POCI-01–0145-FEDER-007274). AML is funded by the Portuguese Government through FCT (IF/01262/2014). PIM is supported by the FCT post-doctoral fellowship (SFRH/BPD/120777/2016), financed from the Portuguese State Budget of the Ministry for Science, Technology and High Education and from the European Social Fund, available through the Programa Operacional do Capital Humano. ToxOmics—Centre for Toxicogenomics and Human Health, Genetics, Oncology and Human Toxicology, Nova Medical School, Lisbon, is also partially supported by FCT (Projects: UID/BIM/00009/2013 and UIDB/UIDP/00009/2020). SLarriba received support from Instituto de Salud Carlos III (grant DTS18/00101], co-funded by FEDER funds/European Regional Development Fund (ERDF)—a way to build Europe), and from “Generalitat de Catalunya” (grant 2017SGR191). SLarriba is sponsored by the “Researchers Consolidation Program” from the SNS-Dpt. Salut Generalitat de Catalunya (Exp. CES09/020). This article is related to the Ph.D. Doctoral Thesis of Miriam Cerván-Martín (grant ref. BES-2017–081222 funded by MCIN/AEI/10.13039/501100011033 and FSE “El FSE invierte en tu futuro”). Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.We aimed to analyze the role of the common genetic variants located in the PIN1 locus, a relevant prolyl isomerase required to control the proliferation of spermatogonial stem cells and the integrity of the blood–testis barrier, in the genetic risk of developing male infertility due to a severe spermatogenic failure (SPGF). Genotyping was performed using TaqMan genotyping assays for three PIN1 taggers (rs2287839, rs2233678 and rs62105751). The study cohort included 715 males diagnosed with SPGF and classified as suffering from non-obstructive azoospermia (NOA, n = 505) or severe oligospermia (SO, n = 210), and 1058 controls from the Iberian Peninsula. The allelic frequency differences between cases and controls were analyzed by the means of logistic regression models. A subtype specific genetic association with the subset of NOA patients classified as suffering from the Sertoli cell-only (SCO) syndrome was observed with the minor alleles showing strong risk effects for this subset (ORaddrs2287839 = 1.85 (1.17–2.93), ORaddrs2233678 = 1.62 (1.11–2.36), ORaddrs62105751 = 1.43 (1.06–1.93)). The causal variants were predicted to affect the binding of key transcription factors and to produce an altered PIN1 gene expression and isoform balance. In conclusion, common non-coding single-nucleotide polymorphisms located in PIN1 increase the genetic risk to develop SCO.publishersversionpublishe

New strategies in vaccine development against picornaviruses

Diseases caused by picornaviruses include a wide range of pathologies affecting man and other species. Through vaccination, important achievements have been accomplished in the control of some of these infections, such as that produced by poliovirus, currently in process of eradication worldwide. Nevertheless many of these pathogens still cause serious health problems, that would be easily prevented if effective and safe vaccines against them were available. Current strategies for the development of vaccines against picornaviruses, particularly those that produce disease in humans, are reviewed in this article

More recent swine vesicular disease virus isolates retain binding to coxsackie-adenovirus receptor, but have lost the ability to bind human decay-accelerating factor (CD55)

Swine vesicular disease virus (SVDV) evolved from coxsackie B virus serotype 5 (CVB5) in the recent past, crossing the species barrier from humans to pigs. Here, SVDV isolates from early and recent outbreaks have been compared for their capacity to utilize the progenitor virus receptors coxsackie-adenovirus receptor (CAR) and decay-accelerating factor (DAF; CD55). Virus titre of CVB5 and SVDV isolates It'66 and UK'72 on human HeLa cells was reduced by pre-incubation with either anti-DAF or anti-CAR antibodies; however, recent SVDV isolates R1072, R1120 and SPA'93 did not infect HeLa cells lytically. CVB5 and SVDV infection of the pig cell line IB-RS-2 was inhibited completely by anti-CAR antibodies for all isolates, and no reduction was observed following pre-incubation of cells with anti-pig DAF antibodies. Expression of human DAF in the pig cell line IB-RS-2 enhanced the virus titre of early SVDV isolates by 25-fold, but had no effect on recent SVDV isolate titre. Binding of radiolabelled CVB5 to IB-RS-2 cells was increased seven- to eightfold by expression of human DAF and binding of early SVDV isolates was increased 1.2-1.3-fold, whereas no increase in binding by recent SVDV isolates was mediated by human DAF expression. Addition of soluble hDAF-Fc inhibited CVB5, but not SVDV, infection of pig cells. Pre-incubation of all viruses with soluble hCAR-Fc blocked infection of IB-RS-2 pig cells completely; titration of the amount of soluble hCAR-Fc required to block infection revealed that early isolate UK'72 was the least susceptible to inhibition, and the most recent isolate, SPA'93, was the most susceptible. © 2005 SGM

Recombinant viruses expressing the foot-and-mouth disease virus capsid precursor polypeptide (P1) induce cellular but not humoral antiviral immunity and partial protection in pigs

The importance of the induction of virus neutralizing antibodies to provide protection against foot-and-mouth disease virus (FMDV) infection is well established. However, recent studies with recombinant adenovirus expressing the precursor polypeptide of the viral capsid (P1) indicate that cattle inoculated with this recombinant vector developed partial protection against FMDV infection, in the absence of a detectable specific humoral response. Other viral vectors have been widely used to induce protective immunity against many pathogens, and it has been reported that the use of different vectors for priming and boosting injections can provide a synergistic effect on this response. In this work, we determined the immunogenicity of two recombinant viruses (adenovirus and vaccinia) expressing P1-FMDV, administered either individually or sequentially, and the protection that they induced against FMDV challenge in pigs. A double immunization with the adeno-P1 virus was the most effective strategy at inducing protective immunity. In contrast to previous reports, the use of two different vectors for priming and boosting did not show a synergistic effect on the protection induced against FMD. Interestingly, immunized pigs developed FMDV-specific T cell responses but not detectable antibodies. Thus, the protection observed was likely to be mediated by a cellular immune response