Latin American Consensus for Pediatric Cardiopulmonary Resuscitation 2017: Latin American Pediatric Critical Care Society Pediatric Cardiopulmonary Resuscitation Committee.

OBJECTIVES: To develop a Latin American Consensus about Pediatric Cardiopulmonary Resuscitation. To clarify, reinforce, and adapt some specific recommendations for pediatric patients and to stimulate the implementation of these recommendations in clinical practice. DESIGN: Expert consensus recommendations with Delphi methodology. SETTING: Latin American countries. SUBJECTS: Experts in pediatric cardiopulmonary resuscitation from 19 Latin American countries. INTERVENTIONS: Delphi methodology for expert consensus. MEASUREMENTS AND MAIN RESULTS: The goal was to reach consensus with all the participating experts for every recommendation. An agreement of at least 80% of the participating experts had to exist in order to deliver a recommendation. Two Delphi voting rounds were sent out electronically. The experts were asked to score between 1 and 9 their level of agreement for each recommendation. The score was then classified into three groups: strong agreement (score 7-9), moderate agreement (score 4-6), and disagreement (score 1-3). Nineteen experts from 19 countries participated in both voting rounds and in the whole process of drafting the recommendations. Sixteen recommendations about organization of cardiopulmonary resuscitation, prevention, basic resuscitation, advanced resuscitation, and postresuscitation measures were approved. Ten of them had a consensus of 100%. Four of them were agreed by all the participants except one (94.7% consensus). One recommendation was agreed by all except two experts (89.4%), and finally, one was agreed by all except three experts (84.2%). All the recommendations reached a level of agreement. CONCLUSIONS: This consensus adapts 16 international recommendations to Latin America in order to improve the practice of cardiopulmonary resuscitation in children. Studies should be conducted to analyze the effectiveness of the implementation of these recommendations.

Conventional but not plasmacytoid dendritic cells foster the systemic virus-induced type I IFN response needed for efficient CD8 T cell priming.

Plasmacytoid dendritic cells (pDCs) are considered to be the principal type-I IFN (IFN-I) source in response to viruses, whereas the contribution of conventional DCs (cDCs) has been underestimated because, on a per-cell basis, they are not considered professional IFN-I-producing cells. We have investigated their respective roles in the IFN-I response required for CTL activation. Using a nonreplicative virus, baculovirus, we show that despite the high IFN-I-producing abilities of pDCs, in vivo cDCs but not pDCs are the pivotal IFN-I producers upon viral injection, as demonstrated by selective pDC or cDC depletion. The pathway involved in the virus-triggered IFN-I response is dependent on TLR9/MyD88 in pDCs and on stimulator of IFN genes (STING) in cDCs. Importantly, STING is the key molecule for the systemic baculovirus-induced IFN-I response required for CTL priming. The supremacy of cDCs over pDCs in fostering the IFN-I response required for CTL activation was also verified in the lymphocytic choriomeningitis virus model, in which IFN-ß promoter stimulator 1 plays the role of STING. However, when the TLR-independent virus-triggered IFN-I production is impaired, the pDC-induced IFNs-I have a primary impact on CTL activation, as shown by the detrimental effect of pDC depletion and IFN-I signaling blockade on the residual lymphocytic choriomeningitis virus-triggered CTL response detected in IFN-ß promoter stimulator 1(-/-) mice. Our findings reveal that cDCs play a major role in the TLR-independent virus-triggered IFN-I production required for CTL priming, whereas pDC-induced IFNs-I are dispensable but become relevant when the TLR-independent IFN-I response is impaired.

Receptor-binding domain-based immunoassays for serosurveillance differentiate efficiently between SARS-CoV2-exposed and non-exposed farmed mink.

During the COVID-19 pandemic, infection of farmed mink has become not only an economic issue but also a widespread public health concern. International agencies have advised the use of strict molecular and serosurveillance methods for monitoring the SARS-CoV2 status on mink farms. We developed 2 ELISAs and a duplex protein microarray immunoassay (MI), all in a double-recognition format (DR), to detect SARS-CoV2 antibodies specific to the receptor-binding domain (RBD) of the spike protein and to the full-length nucleoprotein (N) in mink sera. We collected 264 mink serum samples and 126 oropharyngeal samples from 5 Spanish mink farms. In both of the ELISAs and the MI, RBD performed better than N protein for serologic differentiation of mink from SARS-CoV2-positive and -negative farms. Therefore, RBD was the optimal antigenic target for serosurveillance of mink farms.

A multiplex assay for the detection of antibodies to relevant swine pathogens in serum.

Livestock industry supports the livelihood of around 1.3 billion people in the world, with swine industry contributing with 30% of total livestock production worldwide. To maintain and guarantee this production, a pivotal point according to the OIE is addressing potential biohazards. To control them, permanent sero-surveillance is crucial to achieve more focused veterinary public health intervention and prevention strategies, to break the chains of transmission, and to enable fast responses against outbreaks. Within this context, multiplex assays are powerful tools with the potential to simplify surveillance programs, since they reduce time, labour, and variability within analysis. In the present work, we developed a multiplex bead-based assay for the detection of specific antibodies to six relevant pathogens affecting swine: ASFV, CSFV, PRRSV, SIV, TB and HEV. The most immunogenic target antigen of each pathogen was selected as the target protein to coat different microsphere regions in order to develop this multiplex assay. A total of 1544 serum samples from experimental infections as well as field samples were included in the analysis. The 6-plex assay exhibited credible diagnostic parameters with sensitivities ranging from 87.0% to 97.5% and specificities ranging from 87.9% to 100.0%, demonstrating it to be a potential high throughput tool for surveillance of infectious diseases in swine.

Development of an antigen Enzyme-Linked AptaSorbent Assay (ELASA) for the detection of swine influenza virus in field samples.

Influenza viruses are highly variable pathogens that infect a wide range of mammalian and avian species. According to the internal conserved proteins (nucleoprotein: NP, and matrix proteins: M), these viruses are classified into type A, B, C, and D. Influenza A virus in swine is of significant importance to the industry since it is responsible for endemic infections that lead to high economic loses derived from poor weight gain, reproductive disorders, and the role it plays in Porcine Respiratory Disease Complex (PRDC). To date, swine influenza virus (SIV) diagnosis continues to be based in complex and expensive technologies such as RT-qPCR. In this study, we aimed to improve actual tools by the implementation of aptamers as capture molecules. First, three different aptamers have been selected using as target the recombinant NP of Influenza A virus expressed in insect cells. Then, these molecules have been used for the development of an Enzyme-Linked AptaSorbent Assay (ELASA) in combination with specific monoclonal antibodies for Influenza A detection. A total of 171 field samples (nasal swabs) have been evaluated with the newly developed assay obtaining a 79.7% and 98.1% sensitivity and specificity respectively, using real time RT-PCR as standard assay. These results suggest that the assay is a promising method that could be used for Influenza A detection in analysis laboratories facilitating surveillance labours.

Therapeutic Effectiveness of Interferon-α2b Against COVID-19: The Cuban Experience.

A prospective observational study was conducted for assessing the therapeutic efficacy of interferon (IFN)-α2b in patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the first month after the coronavirus disease 2019 (COVID-19) outbreak began in Cuba. From March 11th to April 14th, 814 patients were confirmed SARS-CoV-2 positive in Cuba. Seven hundred sixty-one (93.4%) were treated with a combination of oral antivirals (lopinavir/ritonavir and chloroquine) with intramuscular administration of IFN-α2b (Heberon® Alpha R, Center for Genetic Engineering and Biotechnology, Havana, Cuba), 3 times per week, for 2 weeks. Fifty-three patients received the approved COVID protocol without IFN treatment. The proportion of patients discharged from hospital (without clinical and radiological symptoms and nondetectable virus by real-time polymerase chain reaction) was higher in the IFN-treated compared with the non-IFN treated group (95.4% vs. 26.1%, P < 0.01). The case fatality rate (CFR) for all patients was 2.95%, and for those patients who received IFN-α2b the CFR was reduced to 0.92. Intensive care was required for 82 patients (10.1%), 42 (5.5%) had been treated with IFN. This report provides preliminary evidence for the therapeutic effectiveness of IFN-α2b for COVID-19 and suggests that the use of Heberon Alpha R may contribute to complete recovery of patients.

Therapeutic Effectiveness of Interferon Alpha 2b Treatment for COVID-19 Patient Recovery.

A previous report on 814 patients who were coronavirus disease 2019 (COVID-19) positive provided preliminary therapeutic efficacy evidence with interferon-α2b (IFN-α2b) in Cuba, from March 11 to April 14, 2020. This study re-evaluates the effectiveness of IFN-α2b during the period from March 11 to June 17, 2020. Patients received a combination of oral antivirals (lopinavir/ritonavir and chloroquine) with intramuscular or subcutaneous administration of IFN-α2b. The primary endpoint was the proportion of patients discharged from the hospital; the secondary endpoint was the case fatality rate, and several outcomes related to time variables were also evaluated. From March 11 to June 17, 2,295 patients had been confirmed to be severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive in Cuba, 2,165 were treated with Heberon® Alpha R, and 130 received the approved protocol without IFN. The proportion of fully recovered patients was higher in the IFN-treated compared with the non-IFN-treated group. Prior IFN treatment decreases the likelihood of intensive care and increases the survival after severe or critical diseases. Benefits of IFN were significantly supported by time variables analyzed. This second report confirmed our preliminary evidence about the therapeutic effectiveness of IFN-α2b in SARS-CoV-2 infection and postulated Heberon Alpha R as the main component within antiviral drugs used in the Cuban protocol COVID-19.

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.

First isolation and molecular characterization of Ehrlichia canis in Spain.

This paper reports the first isolation and culture of Ehrlichia canis in Spain from a naturally infected dog using the DH82 cell line. After DNA extraction and PCR amplification, a nearly complete (1412bp) sequence of the 16S rRNA gene of the new E. canis strain was obtained. The GenBank accession number for the nucleotide sequence of this strain is AY394465. This sequence was aligned with the 16S rRNA gene sequences of other Ehrlichia strains accessible in GenBank. The 16S rRNA gene sequence of the E. canis strain reported here showed a high percentage of similarity with the 16S rRNA gene sequence of E. canis from different geographic areas including Japan, Venezuela and Israel. These data confirm the presence of E. canis in Spain.

Current ante-mortem techniques for diagnosis of bovine tuberculosis.

Bovine tuberculosis (TB), mainly caused by Mycobacterium bovis, is a zoonotic disease with implications for Public Health and having an economic impact due to decreased production and limitations to the trade. Bovine TB is subjected to official eradication campaigns mainly based on a test and slaughter policy using diagnostic assays based on the cell-mediated immune response as the intradermal tuberculin test and the gamma-interferon (IFN-γ) assay. Moreover, several diagnostic assays based on the detection of specific antibodies (Abs) have been developed in the last few years with the aim of complementing the current diagnostic techniques in the near future. This review provides an overview of the current ante-mortem diagnostic tools for diagnosis of bovine TB regarding historical background, methodologies and sensitivity (Se) and specificity (Sp) obtained in previous studies under different epidemiological situations.

Evaluation of the performance of cellular and serological diagnostic tests for the diagnosis of tuberculosis in an alpaca (Vicugna pacos) herd naturally infected with Mycobacterium bovis.

Tuberculosis (TB) in llamas and alpacas has gained importance in recent years since they are imported into the European Union mainly for serving as pets and for production of natural fibre. The intradermal tuberculin test has been widely used for diagnosis of TB in these species showing lack of sensitivity (Se) although little information has been previously reported evaluating the effect on its performance of different PPD inoculation sites and time of readings. Moreover, different cost-effective serological assays have been developed in the recent years for TB diagnosis in camelids obtaining a variety of results and, for this reason, new assays still being developed. The main objectives of this study were: (1) to evaluate the performance of the intradermal tuberculin test using different inoculation sites (axillary, prescapular and cervical) and times of reading (72 and 120 h) and (2) to test a novel serological assay based on MPB83 antigen in a Mycobacterium bovis naturally infected alpaca herd in Spain. In regards to skin test, single intradermal tuberculin (SIT) test at the prescapular site and reading at 72 h showed the highest proportion of test-positive-culture positive animals among all culture positive animals (T+/C+), ranging from 53.8% (95% CI, 37.2-69.9) to 80% (95% CI, 44.4-97.5) using a more stringent interpretation than typically prescribed although, in general, low T+/C+ was achieved using both SIT and single comparative intradermal tuberculin (SCIT) tests alone. T+/C+ of the serological assay increased using samples collected 15-30 days after PPD injection [76.9% (95% CI, 60.7-88.9) - 100% (95% CI, 69.2-100)]. The best results of T+/C+ were obtained applying in parallel the most sensitive SIT test and serology using samples collected 15-30 days after PPD inoculation [90% (95% CI, 55.5-99.7)-100% (95% CI, 69.2-100)]. Therefore implementation of serology in parallel with the most sensitive skin test could maximize the detection of infected animals.

Novel and sensitive ELISA for the rapid quantification of recombinant p64K protein.

The antigenic P64k protein from the pathogenic bacterium Neisseria meningitidis has been used as an immunological carrier in several conjugated vaccines. The aim of this report was to develop and validate a sensitive sandwich enzyme-linked immunosorbent assay (ELISA) for the quantification of recombinant p64k protein, to perform both manufacturing process and identification in different vaccine preparations. Validation studies were performed according to the guidelines of the International Conference of Harmonization (ICH). The reference curve showed to be precise and accurate over the entire linear range of 1.25 and 20ng/mL with a limit of quantification validated to 1.25ng/mL. The intra- and inter-assay coefficient of variation ranged from 0.35 to 6.65% and 4.70 to 10.63%, respectively. The ANOVA test used in the specificity/interference study revealed parallelism among curves (p>0.1), which indicates the lack of interference in the working range. Recovery obtained from the accuracy test, using three concentration levels, varied between 94 and 111%, confirming the assay's reliability. The short-term study shown the P64k is stable to -20°C up to 1-week. This ELISA was fully used to assess its manufacturing process and molecular interaction issues in several vaccine preparations. Thus, this immunoassay could be an excellent analytical choice to characterize the quality of that recombinant protein in several contexts as manufacturing process and molecular conjugates.

A combinatorial strategy of a new monoclonal ELISA and immunoaffinity chromatography using sodium deoxycholate to increase the recovery of multimeric proteins like r-HBsAg.

In this work, a sandwich monoclonal-based ELISA for quantifying the HBsAg obtained from yeast cells was standardized and validated. The monoclonal antibody employed in this assay reacts uniformly with different molecular isoforms of r-HBsAg. Immunoassay allowed the r-HBsAg quantification in an analytical range 11.9-191.7 ng/mL. Inter- and intra-assay precision variation coefficients were between 0.77-3.43% and 1.95-8.89%, respectively, and the recovery ranged 98.2-100.8%; which confirms its reliability. r-HBsAg is a complex of carbohydrates, proteins and lipids assembled into spherical particles with an average diameter of 24 nm. Many host contaminants accompany this protein during purification process, which can interfere the antigen recognition by the immunoaffinity matrix. To solve this problem, the effect of several detergents in the quantification and purification of r-HBsAg were studied. The addition of the surfactant sodium deoxycholate (NaDoc) at 0.1% in this ELISA improved the recognition and quantification of r-HBsAg by 2.4-fold higher than untreated samples. Similar results were observed in the immunoaffinity chromatography where a 1.5-fold increasing recovery values was shown. The application of NaDoc allows to reduce the inhibitory effect upon the antigen-antibody recognition, increasing the quantification and immunoaffinity chromatography efficiency. This analytical combination could be applied to multimeric proteins like r-HBsAg of HB vaccine.

Insect baculoviruses strongly potentiate adaptive immune responses by inducing type I IFN.

Baculoviruses (BVs) are dsDNA viruses that are pathogenic for insects. They have been used worldwide as selective bioinsecticides and for producing recombinant proteins in insect cells. Surprisingly, despite their widespread use in research and industry and their dissemination in the environment, the potential effects of these insect viruses on the immune responses of mammals remain totally unknown. We show in this study that BVs have strong adjuvant properties in mice, promoting potent humoral and CD8(+) T cell adaptive responses against coadministered Ag. BVs also induce the in vivo maturation of dendritic cells and the production of inflammatory cytokines. We demonstrate that BVs play a major role in the strong immunogenicity of virus-like particles produced in the BV-insect cell expression system. The presence of even small numbers of BVs among the recombinant proteins produced in the BV expression system may therefore strengthen the immunological properties of these proteins. This adjuvant behavior of BVs is mediated primarily by IFN-alphabeta, although mechanisms independent of type I IFN signaling are also involved. This study demonstrates that nonpathogenic insect viruses may have a strong effect on the mammalian immune system.

Non-induced leukocyte extract reduces HIV replication and TNF secretion.

According to UNAIDS, the global HIV/AIDS epidemic increased to 40 million the number of people living with the virus around the world. Dialyzable leukocyte extract obtained by our group is a low molecular weight dialyzable material from peripheral human leukocytes previously in vitro induced with Sendai virus (DLE-ind), and more recently, from non-induced leukocytes (DLE n/i). Previous results have shown the ability of DLE-ind to inhibit HIV in vitro replication in MT4 cell; to reduce TNFalpha secretion, and to delay in vivo progression to AIDS in early stage of HIV infection. In this work we present evidences that DLE n/i also inhibits HIV in vitro replication and reduces TNFalpha secretion in human whole blood like DLE obtained from induced leukocytes. Taking together these results show that both properties of DLE, HIV in vitro inhibition and TNF production modulation, are not dependent on in vitro Sendai virus induction of leukocytes.