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Enciso-Moreno, J. A.

Publications and source records attributed to Enciso-Moreno, J. A..

2 recordsLinked to original sources

Genomics epidemiology analysis reveals hidden signatures of drug resistance in Mycobacterium tuberculosis

Mycobacterium tuberculosis (Mtb) causes the majority of reported cases of human tuberculosis (TB), one of the deadliest infectious diseases worldwide. New diagnostic tools and approaches to detect drug-resistance must be introduced by 2025 to achieve the End-TB Strategy goals set for 2030 by the WHO. Genomic epidemiology of TB has allowed the expansion of catalogs listing genetic signatures of Mtb drug-resistance. However, very few Mtb strains from Latin America have participate in previous genomic epidemiologic efforts. Here we present the first functional genomic epidemiology study of drug-resistant Mtb strains in Mexico, incorporating the genomic characterization of 133 genomes, including 53 newly sequenced isolates, to provide a comprehensive phylogeographic analysis of drug resistant Mtb in Mexico. The study evidences the prevalence of Euro-American Lineage L4 (96.2%), featuring a uniform distribution of the sublineages X-type (33.08%), LAM (22.56%), and Haarlem (21.05%). Our results demonstrate low levels of agreement with traditional drug sensitivity tests (DST), raising concerns for drug-resistant isolates lacking any previously reported genetic signatures of resistance. Finally, we propose a novel functional networking tool (FuN-TB) to explore metabolic and cellular signatures of drug resistance. Applying functional genomics approaches to Latin American Mtb genomes will provide new drug-resistance screening targets that can contribute to bed side decision-making and advise local public policy. Abstract importanceWe presented the first phylogeographic analysis of Mycobacterium tuberculosis (Mtb) of Mexico. Our analysis integrates 133 genome sequences and is focused on the identification of genetic signatures associated to drug-resistance. The results show the geographic distribution of sublineages and drug-resistance phenotypic classes. Additionally, we propose a novel functional networking tool (FuN-TB) to explore metabolic and cellular signatures of drug resistance associated. We show for the first time that Mtb isolates from Mexico encode for region-specific genetic signarures of antimicrobial resistance. Applying functional genomics approaches to Latin American Mtb genomes will provide new drug-resistance screening targets that can contribute to bed side decision-making and advise local public policy.

genomics↗

A pseudotyped lentivirus-based assay to titer SARS-CoV-2 neutralizing antibodies in Mexico

Measuring the neutralizing potential of SARS-CoV-2 antigens-exposed sera informs on effective humoral immunity. This is relevant to 1-monitor levels of protection within an asymptomatic population, 2-evaluate the efficacy of existing and novel vaccines against emerging variants, 3-test prospective therapeutic monoclonal neutralizing antibodies (NAbs) and, overall, to contribute to understand SARS-CoV-2 immunity. However, the gold-standard method to titer NAbs is a functional assay of virus-mediated infection, which requires biosafety level 3 (BSL-3) facilities. As these facilities are insufficient in Latin American countries, including Mexico, scant information has been obtained about NAb in these countries during the COVID-19 pandemic. An alternative solution to acquire NAb information locally is to use non-replicative viral particles that display the SARS-CoV-2 Spike (S) protein on their surface, and deliver a reporter gene into target cells upon transduction. Here we present the development of a NAb-measuring assay based on Nanoluc-mediated luminescence measurements from SARS-CoV-2 S-pseudotyped lentiviral particle-infected cells. The successive steps of development are presented, including lentiviral particles production, target cell selection, and TCID50 determination. We applied the optimized assay in a BSL-2 facility to measure NAbs in 15 pre-pandemic, 18 COVID-19 convalescent and 32 BNT162b2 vaccinated serum samples, which evidenced the assay with 100% sensitivity, 86.6% specificity and 96% accuracy. The assay highlighted heterogeneity in neutralization curves which are relevant in discussing neutralization potency dynamics. Overall, this is the first report of a BSL-2 safe functional assay to measure SARS-CoV-2 in Mexico and a cornerstone methodology necessary to measure NAb with a functional assay in the context of limited resources settings. ImportanceEvaluating effective humoral immunity against SARS-CoV-2 requires a functional assay with infectious virus. Handling the authentic SARS-CoV-2 virus requires specialized facilities that are not readily available in Latin America, including Mexico. Here we produce non-replicative viral particles pseudotyped with the SARS-CoV-2 S protein that are used as safe surrogate viral particles in an optimized BSL-2 ready neutralization assay. The establishment of this assay is critical to allow the evaluation of effective humoral immunity to SARS-CoV-2 post-infection and to monitor the efficacy of existing or novel vaccines against emerging variants in the Mexican population.

microbiology↗