Theme 8: Respiratory infection

Supervisors:  Dr Paul King
Telephone: 9594 6666
Email: Paul.King@med.monash.edu.au

Respiratory bacterial infection is extremely common and is probably the most common cause for patients needing to go and seek medical attention. The outcome in respiratory infection is primarily determined by the interaction between the bacterial pathogen and host immune response.  The nature of the protective immune response is generally not well understood.

We have a longstanding research interest in assessing the immune response to common bacteria.  Our work has concentrated on clinical samples from patients and cell lines. We have expertise in wide variety of techniques including flow cytometry, molecular biology, confocal microscopy and intracellular survival assays.

1: The role of toll receptors in diagnosing respiratory infection

Supervisors; Dr Paul King and Associate Professor Kumar Visvanathan

Toll like receptors (TLRs) are expressed by phagocytic cells (neutrophils and macrophages) as an early response to infection and help direct the protective immune response. They are also potentially useful markers of specific infection. This project will assess phagocytic cells and fluid taken from the airways of patient using a test called a bronchoscopy. The cells will be labelled with specific antibodies for TLR 2, 3 and 4 and expression will be measured using flow cytometry.  The fluid will be cultured for the presence of bacteria and viruses using standard culture methods. The results of the TLR expression and microbial culture will then be correlated. This project may be able to demonstrate that TLR expression is a new and powerful tool to diagnose respiratory infection.

2: The role of Vitamin D deficiency in chronic bronchitis

Supervisors; Dr Paul King and Associate Professor Kumar Visvanathan

Vitamin D is an essential hormone needed for healthy bones and a functional immune system. Vitamin D is primarily produced by sun exposure on the skin. Lack of adequate sunlight results in Vitamin D deficiency and this is now extremely common. Vitamin D deficiency appears to have a particularly important role in chronic respiratory infection such as Tuberculosis. This project will measure the immune response in subjects who have Vitamin D deficiency and chronic bronchitis. A variety of common immune parameters will be measured including detailed cell types, lymphocyte and phagocytic function.  The effect of Vitamin D on in vitro responses will also be assessed.  If Vitamin D deficiency is established as being important in chronic bronchitis this will have direct implications for patient treatment.

 3: Defining intracellular behaviour of nontypeable Haemophilus influenzae

Supervisor; Dr Paul King

Nontypeable Haemophilus influenzae (NTHi) is the dominant cause of respiratory bacterial infection including tonsillitis, sinusitis, ear infection and bronchitis. This bacterium has adapted to the human host and is found in the throat of most healthy adults. It only causes clinical disease in a minority of people it infects. One potentially important mechanism of causing disease is the ability to invade host cells and live intracellularly. This project will attempt to define the mechanisms of intracellular survival of NTHi using patient cells and cell lines. The techniques used will include confocal microscopy, flow cytometry and intracellular survival assays.