InnovatePeru [382-PNICP-PIBA-2014 and 297INNOVATEPERU-EC-2016 to P.M.]; Fondo Nacional de Desarrollo Cientifico, Tecnologico y de Innovacion Tecnologica [154-2017-Fondecyt and 0362019-Fondecyt-BM-INC.INV to P.M.]; FIRB Futuro in Ricerca [RBFR130VS5 001 to A.F.]; Italian Ministero dell'Istruzione, dell'Universita e della Ricerca (to A.F.); Part of the work on structural dynamics of the ribosome was supported by Russian Science Foundation [17-1401416 to A.L.K.]. Funding for open access: Universidad Peruana de Ciencias Aplicadas (Exp-03).

Tegumentary leishmaniasis, a disease caused by protozoan parasites of the genus Leishmania, is a major public health problem in many regions of Latin America. Its diagnosis is difficult given other conditions resembling leishmaniasis lesions and co-occurring in the same endemic areas. A combination of parasitological and molecular methods leads to accurate diagnosis, with the latter being traditionally performed in centralized reference and research laboratories as they require specialized infrastructure and operators. Clustered regularly interspaced short palindromic repeats/CRISPR-associated protein (CRISPR/Cas) systems have recently driven innovative tools for nucleic acid detection that combine high specificity, sensitivity and speed and are readily adaptable for point-of-care testing. Here, we harnessed the CRISPR-Cas12a system for molecular detection of Leishmania spp., emphasizing...

Rapid Diagnostic Tests (RDTs) for malaria are restricted to a few biomarkers and antibody-mediated detection. However, the expression of commonly used biomarkers varies geographically and the sensibility of immunodetection can be affected by batch-to-batch differences or limited thermal stability. In this study we aimed to overcome these limitations by identifying a potential biomarker and by developing molecular sensors based on aptamer technology. Using gene expression databases, ribosome profiling analysis, and structural modeling, we find that the High Mobility Group Box 1 protein (HMGB1) of Plasmodium falciparum is highly expressed, structurally stable, and present along all blood-stages of P. falciparum infection. To develop biosensors, we used in vitro evolution techniques to produce DNA aptamers for the recombinantly expressed HMG-box, the conserved domain of HMGB1. An evolutiona...

Low- and middle-income countries (LMICs) are significantly affected by SARS-CoV-2, partially due to their limited capacity for local production and implementation of molecular testing. Here, we provide detailed methods and validation of a molecular toolkit that can be readily produced and deployed using laboratory equipment available in LMICs. Our results show that lab-scale production of enzymes and nucleic acids can supply over 50,000 tests per production batch. The optimized one-step RT-PCR coupled to CRISPR-Cas12a-mediated detection showed a limit of detection of 102 ge/μL in a turnaround time of 2 h. The clinical validation indicated an overall sensitivity of 80%–88%, while for middle and high viral load samples (Cq ≤ 31) the sensitivity was 92%–100%. The specificity was 96%–100% regardless of viral load. Furthermore, we show that the toolkit can be used with the mobile lab...