Exploring the diagnostic synergy of isothermal amplifications integrated CRISPR technology for Tuberculosis: A systematic review

Abstract

To address the problems linked with Mycobacterium tuberculosis (MTB) detection, we need an accurate, sensitive, and faster detection method for efficient epidemiological management for tuberculosis (TB) diagnosis. Nucleic acid-based diagnosis of TB is more sensitive and specific but majorly requires trained workers and costly infrastructure. Isothermal amplification methods due to their negligible infrastructure requirements have paved way for the efficient and rapid diagnosis of TB, however, they sometimes suffer with drawbacks like false positive results, challenges in primer designing. With progress in clustered regularly interspaced short palindromic repeats-CRISPR associated protein (CRISPR-Cas) integrated nucleic acid detection methods the above limitations are being overcome for pathogen detection. The combination of CRISPR with any suitable isothermal technologies like recombinase polymerase amplification (RPA) or loop-mediated isothermal amplification (LAMP), offers several advantages due to the higher sensitivity, specificity, versatility and reproducibility as a point of care. Thus, in this review, we aimed to provide a comprehensive overview of the various isothermal amplification methods coupled CRISPR-based TB diagnostic studies that are reported in the literature. About 12 articles were included in this review using predefined selection criteria. Data were extracted for detailed review from PubMed, Google Scholar and Science Direct and the diagnostic efficiency was evaluated. The data uncovered that most of the studies were conducted in China with IS6110 and IS6108 as the major target genes utilised. The most commonly used detection methods were based on fluorescence and lateral flow. Overall, we observed good sensitivity and specificity of Isothermal techniques linked with CRISPR. Taken together, the synergy between Isothermal amplification methods and CRISPR-Cas technique could be a potential alternative to qPCR, GeneXpert, and conventional acid-fast staining, particularly in low-resource regions for easy and rapid TB diagnosis.