Browsing by Author "Gaggero, Aldo"

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    Differential neutralizing antibody responses elicited by CoronaVac and BNT162b2 against SARS-CoV-2 Lambda in Chile
    (2022) Acevedo, Monica L.; Gaete-Argel, Aracelly; Alonso-Palomares, Luis; de Oca, Marco Montes; Bustamante, Andres; Gaggero, Aldo; Paredes, Fabio; Cortes, Claudia P.; Pantano, Sergio; Martinez-Valdebenito, Constanza; Angulo, Jenniffer; Le Corre, Nicole; Ferres, Marcela; Navarrete, Marcelo A.; Valiente-Echeverria, Fernando; Soto-Rifo, Ricardo
    The SARS-CoV-2 Lambda variant has been prevalent in Latin America. An analysis of the neutralization capacity of antibodies elicited by CoronaVac and BNT162b2 against SARS-CoV-2 Lambda in plasma from healthcare workers and patients in Chile reveals that BNT162b2 elicits higher neutralizing antibody titres than CoronaVac.
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    Insights into neutralizing antibody responses in individuals exposed to SARS-CoV-2 in Chile
    (2021) Beltrán Pavez, Carolina; Riquelme Barrios, Sebastián; Oyarzún Arrau, Aarón; Gaete Argel, Aracelly; González Stegmaier, Roxana; Cereceda Solis, Karina; Aguirre, Adam; Travisany, Dante; Palma Vejares, Ricardo; Barriga, Gonzalo P.; Gaggero, Aldo; Martínez Valdebenito, Constanza; Le Corre Pérez, Monique Nicole; Ferrés, Marcela; Balcells Marty, María Elvira; Fernández, Jorge; Ramírez, Eugenio; Villarroel, Franz; Valiente Echeverría, Fernando; Soto Rifo, Ricardo
    Chile has one of the worst numbers worldwide in terms of SARS-CoV-2 positive cases and COVID-19-related deaths per million inhabitants; thus, characterization of neutralizing antibody (NAb) responses in the general population is critical to understanding of immunity at the local level. Given our inability to perform massive classical neutralization assays due to the scarce availability of BSL-3 facilities in the country, we developed and fully characterized an HIV-based SARS-CoV-2 pseudotype, which was used in a 96-well plate format to investigate NAb responses in samples from individuals exposed to SARS-CoV-2 or treated with convalescent plasma. We also identified samples with decreased or enhanced neutralization activity against the D614G spike variant compared with the wild type, indicating the relevance of this variant in host immunity. The data presented here represent the first insights into NAb responses in individuals from Chile, serving as a guide for future studies in the country.
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    Merkel cell polyomavirus in non-small cell lung carcinomas from Chile
    (ACADEMIC PRESS INC ELSEVIER SCIENCE, 2012) Gheit, Tarik; Pablo Munoz, Juan; Levican, Jorge; Gonzalez, Carolina; Ampuero, Sandra; Parra, Barbara; Gaggero, Aldo; Corvalan, Alejandro H.; Meneses, Manuel; Tommasino, Massimo; Aguayo, Francisco
    Lung cancer is a leading pathology strongly associated with the smoking habit. However, a viral etiology for a subset of patients developing lung cancer has been suggested. Polyomaviruses (PyVs) are small double stranded DNA viruses associated with the development of some human diseases. However, a causal role of these viruses in human cancer has been difficult to demonstrate. In this study, eighty-six non-small cell lung carcinomas (NSCLCs), including adenocarcinomas (AdCs) and squamous cell lung carcinomas (SQCs) from Chile were analyzed for the presence of PyVs using polymerase chain reaction (PCR). All of the specimens were positive for a fragment of the betaglobin gene. We found that 4/86 (4.7%) of lung carcinomas were positive for PyVs. After sequencing and BlastN alignment, all four cases were identified as Merkel cell polyomaviruses (MCV) that corresponded to two AdCs and two SQCs. A non-significant statistical association was found between the presence of MCV and clinic-pathological features of the patients and tumors. In addition, 1/4 (25%) of the carcinomas were actively expressing large T antigen (LT) transcripts, as demonstrated by reverse-transcriptase PCR (RT-PCR). Thus a possible role of MCV in a very small subset of patients with lung cancer cannot be ruled out and warrants more investigation. (C) 2012 Elsevier Inc. All rights reserved.
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    Monkeypox Virus in Wastewater Samples from Santiago Metropolitan Region, Chile
    (2023) Ampuero, Manuel; Martinez-Valdebenito, Constanza; Ferres, Marcela; Soto-Rifo, Ricardo; Gaggero, Aldo
    Sewage surveillance provides useful epidemiologic and public health information on viral infections at the population level. We detected monkeypox virus DNA from sewage samples covering 85% of the population in Santiago Metropolitan Region, Chile. We also isolated infective viruses from those samples. Wastewater surveillance could complement clinical surveillance for monkeypox virus.
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    Performance of SARS-CoV-2 rapid antigen test compared with real-time RT-PCR in asymptomatic individuals
    (2021) Pena, Monica; Ampuero, Manuel; Garces, Carlos; Gaggero, Aldo; Garcia, Patricia; Soledad Velasquez, Maria; Luza, Ricardo; Alvarez, Pia; Paredes, Fabio; Acevedo, Johanna; Farfan, Mauricio J.; Solari, Sandra; Soto-Rifo, Ricardo; Valiente-Echeverria, Fernando
    Screening, testing and contact tracing plays a pivotal role in control of the COVID-19 pandemic. To enable this it is necessary to increase the testing capacity. This study compared a SARS-CoV-2 rapid antigen test (RAT) and RT-PCR in 842 asymptomatic individuals from Tarapaca, Chile. A sensitivity of 69.86%, specificity of 99.61%, PPV of 94.44% and NPP of 97.22% with Ct values (Ct > 27) that were significantly higher among individuals with false-negative RAT were reported. These results support the fact that RAT might have a significant impact on the identification of asymptomatic carriers in areas that lack suitable laboratories to perform SARS-CoV-2 real-time RT-PCR diagnostics, or the results take more than 24-48 h, as well as zones with high traffic of individuals such as border/customs, airports, interregional bus, train stations or in any mass testing campaign requiring rapid results.