个人简介
Dr. Jinyu Shan
Dr. Jinyu Shan
Phelix Research & Development/University of Leicester, UK
标题: Combatting Lyme disease: phages the ‘sharpshooters’ of enemy bacteria
摘要: 
Lyme disease (LD) is caused by the bacteria Borrelia burgdorferi sensu lato (s.l.) and is transmitted to humans through the bite of infected ticks (Fig. 1A, 1B). LD is the most commonly reported tick-born disease in the United States with the Centre for Disease Control and Prevention (CDC) reporting more than 300 000 cases annually. In Europe, the number of LD cases has increased steadily over the last two decades with an estimation of approximately 85 000 cases every year. These numbers are likely to be an under-representation due to issues with diagnosis.

The current diagnosis of LD is based on clinical presentation. The FDA-approved laboratory diagnosis is serological test, which cannot detect early LD (ELD) and is too low in sensitivity, missing around 50% of patients. Early diagnosis is vital because ELD can be treated effectively with antibiotics but is harder to treat if the infection is allowed to develop into late LD (LLD). In addition, studies of Borrelia infections in animal models revealed the presence of Borrelia after antibiotic therapy, which suggests that antibiotics may be unable to eradicate Borrelia. 

We aim to improve the current diagnostic and therapeutic approaches using bacterial viruses known as phages. Each phage only targets one bacterial species and therefore they can be seen as ‘sharpshooters’ to remove key bacterial pathogens (Fig 1C, 1D). Therefore, a phage that would kill Lyme disease wouldn’t kill other bacterial species and most definitely wouldn’t harm human cells. Phages have been used effectively to target many bacterial infections, and there is currently a revival of phage therapy (clinical application of phages in treating bacterial infections) around the world. Before our work, very little research has been carried out on phages that infect Borrelia species.



Fig. 1 A: Borrelia, the causative agents of Lyme disease, in aggregate form; B: Borrelia in free living form; C: Phages in a group; D: an individual phage.

We developed a highly sensitive and reliable qPCR assay targeting Borrelia phages to diagnose LD. To evaluate the performance of the phage-based qPCR (p-qPCR) relative to the serological test and bacterium-based qPCR (b-qPCR), 96 LLD samples were examined. The p-qPCR yielded positive results from 88 (92%) samples. In contrast, a total of 16 (17%) samples were positive by serological test, while 12 (12.5%) samples showed positive by b-qPCR (table 1 and 2). It is worth mentioning that all serological positive or b-qPCR positive samples were also positive by the p-qPCR. Additionally, out of 14 serological negative ELD samples, 7 (50%) showed positive by the p-qPCR, but none showed positive by b-qPCR. Further evaluation was conducted against ~1000 ticks collected from ~200 geographical locations throughout the UK. An average of 38% of ticks were positive by the qPCR. This novel test would significantly improve the current Lyme diagnostic standards, and therefore would provide essential evidence for clinicians to better manage/treat a large number of patients with a negative Lyme diagnostic result. A fully validated phage-based Lyme diagnostic method would transform current Lyme clinical practice. 

To investigate phage-based therapeutics, we established methods for isolating Borrelia phages from ticks and are currently working on phage characterisation. We also developed procedures for measuring in vitro ‘anti-Borrelia’ activity of phage and phage-encoded enzymes, holins (enzymes that rupture bacterial cytoplasmic membranes) and endolysin (enzymes that break down bacterial cell walls).
简介: 
Jinyu Shan earned his bachelor’s and master’s degrees at two universities in China, one in industrial microbiology at Shandong University (山东) and the other in petroleum microbiology at Nankai (南开)University. After graduation, he took two contract jobs at Chinese University of Hong Kong (香港中文大学) and University of Hong Kong (香港大学). In 2003, he was admitted to a PhD programme (An investigation into the molecular mechanism of phage infection on marine cyanobacteria) under the supervision of Professor Nick Mann at University of Warwick, UK. After the PhD, Jinyu worked as a Post-Doctoral Researcher for Professor Martha Clokie based at University of Leicester, UK. Jinyu’s expertise and interests are in phage (viruses infecting bacteria) therapy (therapeutic application of phages to combat pathogenic bacterial infections) and pre-clinical development of phages targeting human pathogens, including Clostridium difficile (hospital superbug) and Burkholderia pseudomallie (the causative agent of meliodosis). Jinyu also has skill set/interest in applying human cell cultures as model systems in investigating the efficacy and mechanism of phage-human cell interactions. Since 2015, Jinyu’s research interests focus on exploiting phages as diagnostic markers for detecting bacterial infections in general, and Borrelia infection (the causative agent of Lyme disease and Relapsing Fever) in particular. He has recently invented and patented phage-based diagnostics targeting Lyme disease and Relapsing Fever. He is currently a non-executive director and the leading Scientist of Phelix Research & Development (a registered medical research charity registered in the UK and France).