Simon Johnston

Krebs Institute Fellow and Principal Investigator.

I did my PhD with Prof. Laura Machesky on the Arp2/3 complex and the actin cytoskeleton, and was a post-doc with Prof. Robin May working on host pathogen interactions of Cryptococcus. Now I am occasionally allowed in the lab to do microscopy, cell work and flow cytometry. To find out more about our research please see our research section.

I am very involved with gender equality through the Medical School Athena SWAN team and I represent the Faculty of Medicine on the University of Sheffield Gender Equality Committee. I am also passionate about public engagement in science and we have a number of past and ongoing projects in this area that can be seen here.

 Aleks Bojarczuk

Aleks joined the Johnston lab in 2012 as a Research Assistant. Aleks previously worked in Steve Renshaw's lab screening for new drugs for inflammation resolution. This work led to this wonderful paper in Science Translational Medicine. Aleks has developed many of the methods and techniques we use in the lab including the high content imaging methods and is currently working on several projects concerning the disruption and activation of macrophages and neutrophils in cryptococcal infection. Aleks likes the colour blue, Lavazza ground coffee, classical music, red wine, jogging, cycling, singing, reading books. Absolutely afraid of fat spiders

 Josie Gibson

Josie is an A* PhD student who is currently in Phil Ingham's lab at the IMCB in Singapore for two years as part of her PhD. Josie is working on differences in phagosome processing in zebrafish models of cryptococcosis and S. aureus infection.

 Alfred Kamuyango

Alfred is Wellcome Trust Strategic Award in Medical Mycology and Fungal Immunology PhD student. He joined the Johnston lab in 2014. Before joining the lab he did an MRes in Medical Mycology and Fungal Immunology where we worked on Aspergillus species and their interaction with chronic granulomatous disease phagocytes. His present PhD project is looking at interaction of C. neoformans with macrophages in zebrafish. He is funded by the Wellcome Trust Strategic Award in Medical Mycology and Fungal Immunology. Alfred likes photography and cycling. Don't take any notice of his photo, he is always smiling.

 Hamid Fehri

Hamid completed his Masters in Biomedical Engineering in 2012 from Amirkabir University of Technology. He joined the Johnston lab as a PhD student (joint with Alejandro Frangi in CISTIB) in January, 2015. He is currently working on the development of methods and tools for generating and analysing light microscopy data of host pathogen interactions in zebrafish, with the aim of generating three-dimensional light microscopy data sets that can be analysed automatically. Aleks will be very pleased when he has done this. Hamid was ranked third as an amateur rallying navigator.  

 Robbie Evans

I completed my PhD at the University of Birmingham with Professor Robin May, during my PhD I worked on the fungal pathogen Cryptococcus neoformans to determine how a lipid modifying virulence factor – phospholipase B1 – is able to promote intracellular proliferation of Cryptococcus within macrophages. I became particularly interested in eicosanoid species produced by cryptococcal phospholipase B1 as it has been hypothesised that these molecules could interfere with host signalling pathways.

After completing my PhD, I moved to the Johnston lab as a British Infection Association postdoctoral fellow. The goals of my fellowship are to understand how eicosanoids produced by C. neoformans during infection are able to manipulate host innate immunity. Using zebrafish, I have identified a specific eicosanoid species produced by C. neoformans (15-keto prostaglandin E2) that is able to promote cryptococcal pathogenesis by activating host Peroxisome proliferator-activated receptor gamma (PPAR-γ). 

 Jaime Canedo

Before joining the Johnston lab as a PhD student, I did a Master's degree in Biophotonics (with distinction) at Cardiff University. My distinct interests on imaging and interdisciplinary research have made me pursue my current project which investigates the biophysical aspects of phagocytosis. The project aims to describe specific molecular events during phagocytosis and changes in the biophysical characteristics of a cell. I am using macrophages and pathogens in my experiments along with advanced techniques in light microscopy, electron microscopy and image processing.

 Jacob Rudman

Jacob finished an integrated Masters degree from the University of Bath in 2017, where he then joined the Johnston lab shortly after in October 2017. He is a PhD student as part of the DiMeN doctoral training program, working on uncovering the initial interactions of macrophages with Cryptococcus Neoformans in vitro and in both zebrafish and mouse models. In a previous life, Jacob was ranked in the top 200 Rock Band gamers in the world.


 Stella Christou

(Ayscough lab)

Stella has completed her undergraduate degree BSc (Hons) Microbiology at the University of Aberdeen, where she developed a deep interest in medical mycology. She joint the Johnston group in 2017 as a joint PhD student with the Kathryn Ayscough group. Her project involves studying the host –pathogen interactions between Candida albicans (human pathogen that causes oral thrush, vaginal candidiasis and invasive candidiasis that can lead to death) and human cells using the zebrafish model. The project aims to understand the importance of APM4 gene involved in Candida endocytosis during host pathogen interactions. Harriet’s project so far has identified that deletion of the gene causes changes in the cell wall composition, the cell wall is very important for the interactions of the pathogen with the host and thus it is extremely important to understand how those are affected during infection so that in the future we could identify possible drug targets.

 Harriet Knafler

(Ayscough lab)

Harriet did her undergraduate degree in Sheffield's MBB department, and moved to BMS in 2015 to do her phD.  She works in the lab of Kathryn Ayscough with Simon Johnston as her second supervisor. She is working on the role of endocytosis in the virulence of a fungal pathogen - Candida albicans. When she's not looking at fungus, she enjoys walks in the Peaks and good pubs. 

 James Bradford

(Hawkins lab)

James completed a Masters degree in Physics and Astrophysics in 2016, where he became interested in using simulations to understand physical systems. He's now a PhD student supervised by Rhoda Hawkins in Physics. His project involves the computational modelling of phagocytosis, to help understand the role of actin in force generation. When not debugging code he's written, James can be found in the pub.













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