Is liquid biopsy mature enough for the diagnosis of Alzheimer's disease?

The preclinical diagnosis and clinical practice for Alzheimer's disease (AD) based on liquid biopsy have made great progress in recent years. As liquid biopsy is a fast, low-cost, and easy way to get the phase of AD, continual efforts from intense multidisciplinary studies have been made to move the research tools to routine clinical diagnostics. On one hand, technological breakthroughs have brought new detection methods to the outputs of liquid biopsy to stratify AD cases, resulting in higher accuracy and efficiency of diagnosis. On the other hand, diversiform biofluid biomarkers derived from cerebrospinal fluid (CSF), blood, urine, Saliva, and exosome were screened out and biologically verified. As a result, more detailed knowledge about the molecular pathogenesis of AD was discovered and elucidated. However, to date, how to weigh the reports derived from liquid biopsy for preclinical AD diagnosis is an ongoing question. In this review, we briefly introduce liquid biopsy and the role it plays in research and clinical practice. Then, we summarize the established fluid-based assays of the current state for AD diagnostic such as ELISA, single-molecule array (Simoa), Immunoprecipitation-Mass Spectrometry (IP-MS), liquid chromatography-MS, immunomagnetic reduction (IMR), multimer detection system (MDS). In addition, we give an updated list of fluid biomarkers in the AD research field. Lastly, the current outstanding challenges and the feasibility to use a stand-alone biomarker in the joint diagnostic strategy are discussed.

CRISPR Cas system: A strategic approach in detection of nucleic acids.

Over the decades, rapid nucleic acid detection has been difficult for scientists, especially in microbiology, biotechnology and immunology. Most technologies are finite in sensitivity, specificity or both. Early diagnosis of disease allows swift response, disease monitoring and control of the rapid spread of the disease. However, limited access to test kits, specialized laboratory equipment, and the need for highly skilled personnel has led to a detection downshift. CRISPR-based diagnostic techniques, based on clustered regularly interspaced short palindromic repeats (CRISPR), have recently altered molecular diagnosis. This modern technology is combined or paired with other methods like SHERLOCK, DETECTR, HUDSON, CDetection and so on to detect viruses, bacteria infection and other pathogenic agents, due to its precision and versatility, it can also detect diseases directly from patient samples. Rapid, sensitive, accurate and advanced molecular techniques are much needed since they soothe researchers in diagnosis and detection, and can also be employed in therapeutic treatments. In this review, detailed CRISPR Cas variants were discussed, emphasizing the use of CRISPR system as a tool in diagnostics and nucleic acids detection and the benefits of this robust tool over other amplification methods.