stella joins fight against COVID-19
The Johnston Labs PhD student Stella, has recently joined Dr Thushan de Silva’s lab in IICD at the University of Sheffield to help in the fight against COVID-19. The lab is part of the COG-UK consortium and sequences COVID-19 from different patients and medical stuff samples.
Stella is really enjoying her time in the labs stating "The process of sequencing is really fun and there is a national attempt to collect as much information from COVID-19 positive patients as possible to hopefully understand the pathogen."
Stella will be back to our lab soon as the position is temporary and part of the BBSRC DTP White Rose program for Professional Internships for PhD students known as PIPs. We are all very proud of her! Congratulations Stella and thank you for all your hard work in these very tough times.
Jaime and Simon's collaboration with a leading research group on pulmonary hypertension in the Medical School has led to a new publication. They found that pulmonary arterial hypertension could be linked to imbalances in the population of polarised macrophages. This was revealed by biochemical and morphological examination of different types of macrophages in both in vivo and in vitro settings.
To find out more about this work, please click on the following link:
11 November 2020
Our resident physicist, Dr James Bradford, had successfully defended his thesis on modelling actin polymerisation and phagocytosis. Such a remarkable feat to figure out some of actin's secrets! We're looking forward for a proper celebration when everything is back to normal.
After the delays due to COVID, we can now say that we are planning the big move to our new lab!
We will be sharing with The Elks lab! It will have dedicated spaces to the microscopy equipment, an infection room and a huge office space. It also has wonderful views over Firth Court. We are excited to move in!
We also had our first socially distanced lab meeting since the start of the pandemic! Its been a while since everyone in the lab had seen each other, but we all enjoyed a nice chilly day at Western Park catching up!
Hopefully we'll be able to have meetings in the new lab soon!
Fungal Disease Awareness Week 2020
The Centers for Disease Control and Prevention (CDC) announced 21st to 25th of September 2020 as the Fungal Disease Awareness Week . The CDC website under the “Think Fungus” headline highlights key publications with insights on fungal disease. We are using this opportunity to discuss the impact of the fungal pathogens studied by the Johnston group in human disease.
The first pathogen we are working on is Candida albicans. Candida is a fungal pathogen that usually lives and co-exists with the human host, however in incidences where the host is weak or has damage to the skin or organs like the gut the fungus gets the chance to switch into an unfriendly pathogen. The disease caused by Candida is called Candidiasis, this is a big group of diseases which can be mild to dangerous depending on the infection. Candidiasis occurs in areas with mucus such as in the vagina and the mouth it is also more commonly named as thrush. In more severe cases it can grow on catheters and can even enter the bloodstream. Bloodstream entry is the most severe cause of Candidiasis. According to statistics from the CDC over 3.6 million US dollars per year are spent to treat Candidiasis which indicates how common this disease can be.
Candida albicans - depending on the host environment - can also prevent or encourage bacterial infections. Candida is an important group of fungal pathogens that sometimes is not very well known by the media because of the varying severity of disease however it is quite critical as there is resistance arising to antifungals and in very ill patients it can even be the leading cause of death.
The second infection we work on is cryptococcosis. Cryptococcosis is mostly caused by Cryptococcus neoformans, or in some cases, by Cryptococcus gattii. Cryptococcus, like Candida, is a kind of yeast that can also cause disease. The majority of people who develop cryptococcosis have a poorly-functioning immune system; for example, those with HIV/AIDS, with certain blood cancers or those taking immune-suppressing medications. Cryptococcus lives in the natural environment, meaning that the source of infection can be certain tree species, or even pigeon poo. We know that it’s inhaled, so infection starts in the lungs. From there, Cryptococcus manages to escape the lungs and infects different organs around the body - the most severe form of which is called cryptococcal meningitis, when it infects the brain. Cryptococcal meningitis is difficult to treat, often difficult to diagnose and nearly uniformly fatal. Cryptococcal meningitis causes hundreds of thousands of deaths every year, and is responsible for 15% of HIV/AIDS-related deaths. Even if you are lucky enough to survive this devastating infection, it’s likely that after the infection, you’ll suffer from its effects for years afterwards.
Click here to learn more!
simon recognised as a super visionary!
We all want to thank and congratulate Dr Simon Johnston for being recognised as a Supervisor for promoting well being!
Every year The University of Sheffield asks students to nominate supervisors who they believe go above and beyond in their job. This year Simon was recognised for his amazing work in encouraging good mental health and well being amongst his students. Thank you Simon for being an amazing supervisor and mentor! You can read more entries here!
sign up to dimen diversity's first event
Our very own Mahrukh Shameem is organising an event as the president of DiMeN Diversity. Mahrukh - part of the MRC DiMeN DTP - is organising an event entitled 'Inspiring Diversity in STEM'. Please sign up to her event which has 4 speakers and 2 interactive sessions!
We are all very excited to attend this webinar! Click here to join us on the 3rd of August 2020!
Our very own Dr. Josie Gibson has published her first paper in Autophagy! Her paper shows hows selective autophagy is beneficial for Staphylococcus aureus infected neutrophils. S. aureus is a significant pathogen of humans in both its sensitive and MRSA forms. Our immune system is very good at controlling this pathogen, but it only takes a slight advantage to the bacterium for them to cause serious diseases. Here we were show that neutrophils control S. aureus infection but some can escape through the phagosome.
Cells can detect when bacteria escape phagosomes. We found that these escaped S. aureus were being attacked via 'xenophagy' and looked at the adapter p62/SQSTM1 that had been previously associated with 'handling' S. aureus. Using a transgenic zebrafish with a tagged p62 and found that p62 marked escaped S. aureus in neutrophils. To support the role of p62/SQSTM1 in the handling of escaped S. aureus, we reduced the amount of p62 in neutrophils and made a p62 that could not activate autophagy. In both cases the infection was made worse. Our research shows the importance and role of p62 in control of S. aureus by neutrophils, how effective neutrophils are at controlling bacteria and how many different ways they need to stay ahead of this and all the other cunning microbes.
For the complete article, please use the following link: https://doi.org/10.1080/15548627.2020.1765521
Figure 1. Staphylococcus aureus location within neutrophils changes from vesicular to cytosolic throughout infection (C) Tg(mpx:eGFP)i114 larvae were injected at 1 dpf with 1500 cfu SH1000 mCherry S. aureus, and imaged at 3 h post-infection. Images were captured every 5 min for 12 h at multiple z planes to follow infected neutrophils over time (scale: 5 µm). (E) S. aureus with Lc3 marking the entire vesicle (scale: 9 µm), demonstrating a vesicle. (F) S. aureus in the cytosol (scale: 9 µm).