4 research outputs found
Data_Sheet_1_A novel detection method for the pathogenic Aeromonas hydrophila expressing aerA gene and/or hlyA gene based on dualplex RAA and CRISPR/Cas12a.PDF
Aeromonas hydrophila is an emerging waterborne and foodborne pathogen with pathogenicity to humans and warm water fishes, which severely threatens human health, food safety and aquaculture. A novel method for the rapid, accurate, and sensitive detection of pathogenic A. hydrophila is still needed to reduce the impact on human health and aquaculture. In this work, we developed a rapid, accurate, sensitive, and visual detection method (dRAA-CRISPR/Cas12a), without elaborate instruments, integrating the dualplex recombinase-assisted amplification (dRAA) assay and CRISPR/Cas12a system to detect pathogenic A. hydrophila expressing aerA and/or hlyA virulence genes. The dRAA-CRISPR/Cas12a method has high sensitivity, which can rapidly detect (about 45 min) A. hydrophila with the limit of detection in 2 copies of genomic DNA per reaction, and has high specificity for three pathogenic A. hydrophila strains (aerA+hlyA−, aerA−hlyA+, and aerA+hlyA+). Moreover, dRAA-CRISPR/Cas12a method shows satisfactory practicability in the analysis of the spiked human blood and stool and fish samples. These results demonstrate that our developed pathogenic A. hydrophila detection method, dRAA-CRISPR/Cas12a, is a promising potential method for the early diagnosis of human A. hydrophila infection and on-site detection of A. hydrophila in food and aquaculture.</p
Table_1_Rapid and Sensitive Detection of Vibrio vulnificus Using CRISPR/Cas12a Combined With a Recombinase-Aided Amplification Assay.DOC
Vibrio vulnificus is an important zoonotic and aquatic pathogen and can cause vibriosis in humans and aquatic animals (especially farmed fish and shrimp species). Rapid and sensitive detection methods for V. vulnificus are still required to diagnose human vibriosis early and reduce aquaculture losses. Herein, we developed a rapid and sensitive diagnostic method comprising a recombinase-aided amplification (RAA) assay and the CRISPR/Cas12a system (named RAA-CRISPR/Cas12a) to detect V. vulnificus. The RAA-CRISPR/Cas12a method allows rapid and sensitive detection of V. vulnificus in 40 min without a sophisticated instrument, and the limit of detection is two copies of V. vulnificus genomic DNA per reaction. Meanwhile, the method shows satisfactory specificity toward non-target bacteria and high accuracy in the spiked blood, stool, and shrimp samples. Therefore, our proposed rapid and sensitive V. vulnificus detection method, RAA-CRISPR/Cas12a, has great potential for early diagnosis of human vibriosis and on-site V. vulnificus detection in aquaculture and food safety control.</p
Table_1_Mucosal-Associated Invariant T Cells Expressing the TRAV1-TRAJ33 Chain Are Present in Pigs.DOCX
Mucosal-associated invariant T (MAIT) cells are a subpopulation of evolutionarily conserved innate-like T lymphocytes bearing invariant or semi-invariant TCRα chains paired with a biased usage of TCRβ chains and restricted by highly conserved monomorphic MHC class I-like molecule, MR1. Consistent with their phylogenetically conserved characteristics, MAIT cells have been implicated in host immune responses to microbial infections and non-infectious diseases, such as tuberculosis, typhoid fever, and multiple sclerosis. To date, MAIT cells have been identified in humans, mice, cows, sheep, and several non-human primates, but not in pigs. Here, we cloned porcine MAIT (pMAIT) TCRα sequences from PBMC cDNA, and then analyzed the TCRβ usage of pMAIT cells expressing the TRAV1-TRAJ33 chain, finding that pMAIT cells use a limited array of TCRβ chains (predominantly TRBV20S and TRBV29S). We estimated the frequency of TRAV1-TRAJ33 transcripts in peripheral blood and tissues, demonstrating that TRAV1-TRAJ33 transcripts are expressed in all tested tissues. Analysis of the expression of TRAV1-TRAJ33 transcripts in three T-cell subpopulations from peripheral blood and tissues showed that TRAV1-TRAJ33 transcripts can be expressed by CD4+CD8−, CD8+CD4−, and CD4−CD8− T cells. Using a single-cell PCR assay, we demonstrated that pMAIT cells with the TRAV1-TRAJ33 chain express cell surface markers IL-18Rα, IL-7Rα, CCR9, CCR5, and/or CXCR6, and transcription factors PLZF, and T-bet and/or RORγt. In conclusion, pMAIT cells expressing the TRAV1-TRAJ33 chain have characteristics similar to human and mouse MAIT cells, further supporting the idea that the pig is an animal model for investigating MAIT cell functions in human disease.</p
Infectious Disease Diagnosis and Pathogen Identification Platform Based on Multiplex Recombinase Polymerase Amplification-Assisted CRISPR-Cas12a System
Controlling and mitigating infectious diseases caused
by multiple
pathogens or pathogens with several subtypes require multiplex nucleic
acid detection platforms that can detect several target genes rapidly,
specifically, sensitively, and simultaneously. Here, we develop a
detection platform, termed Multiplex Assay of RPA and Collateral Effect
of Cas12a-based System (MARPLES), based on multiplex nucleic acid
amplification and Cas12a ssDNase activation to diagnose these diseases
and identify their pathogens. We use the clinical specimens of hand,
foot, and mouth disease (HFMD) and influenza A to evaluate the feasibility
of MARPLES in diagnosing the disease and identifying the pathogen,
respectively, and find that MARPLES can accurately diagnose the HFMD
associated with enterovirus 71, coxsackievirus A16 (CVA16), CVA6,
or CVA10 and identify the exact types of H1N1 and H3N2 in an hour,
showing high sensitivity and specificity and 100% predictive agreement
with qRT-PCR. Collectively, our findings demonstrate that MARPLES
is a promising multiplex nucleic acid detection platform for disease
diagnosis and pathogen identification