Christian Tjiam
Senior Research Fellow
BSc BMedSc(hons) PhD
christian.tjiam@thekids.org.au
Dr Tjiam is an immunologist at The Kids Research Institute Australia where he leads a collaborative program of research in vaccine immunology. He aims to understand the immunological mechanisms required for lasting vaccine protection. Towards this goal, his work encompasses:
- Characterisation of upper respiratory mucosal immunity
- Defining cellular mechanisms of action of intranasal vaccines
- Understanding the immunogenicity and immune dynamics of heterologous vaccine schedules.
His research uses systems-level approaches that integrates high-dimensional, antigen-specific spectral flow cytometry (of B and T cells) and data science techniques to evaluate vaccine performance in randomised clinical trials and pre-clinical vaccine models.
Dr Tjiam’s expertise sits at the intersection of technical, clinical and fundamental science, with prior appointments as Senior Technical Officer (Flow Cytometry) at Curtin University, as Chair of WA Cytometry and as Scientist-In-Charge (Immunopathology) at PathWest Laboratory Medicine WA. Dr Tjiam is also an Adjunct Lecturer at The University of Western Australia, where he teaches on Immunology, Clinical Immunopathology and Cytometry, and supervises HDR students in original research.
Education and Qualifications
- Doctor of Philosophy, Immunology – The University of Western Australia
- Bachelor of Medical Science (Hons), Immunology – The University of Western Australia
- Bachelor of Science, Pharmacology and Pathology – The University of Western Australia
Projects
Gender and Immunity Study (GIM)
The Gender and IMmunity study (GIM) aims to evaluate how gender-affirming hormone therapy impacts the immune system in young trans individuals, and how this translates to short and long-term health outcomes.
February 2025
Temporal dynamics of B cell dysfunction and EBV responses in early multiple sclerosis
Multiple sclerosis (MS) is an incurable condition where a person’s immune system mistakenly attacks their own brain and spinal cord.
Published research
Plasma testosterone concentration is correlated with circulating immune cell abundance in transgender young people on gender-affirming hormone treatment
Sex hormones, such as oestrogen and testosterone, display significant immune modulatory properties. This is highly relevant for transgender (trans) people who undergo gender-affirming hormone (GAH) treatment. However, only a limited number of studies have evaluated the immunological impact of GAH treatments, and almost none have assessed the impact in trans young people.
The Platform Trial In COVID-19 priming and BOOsting : The immunogenicity, reactogenicity, and safety of licensed COVID-19 vaccinations administered as a second booster in BNT162b2
PICOBOO is a randomised, adaptive trial evaluating the immunogenicity, reactogenicity, and safety of COVID-19 booster strategies. Here, we present data for second boosters among individuals aged 18-<50 and 50-<70 years old primed with BNT162b2 until Day (D) 84.
The Platform trial In COVID-19 vaccine priming and BOOsting (PICOBOO) booster vaccination substudy protocol
Coronavirus-2019 (COVID-19) vaccination in Australia commenced in February 2021. The first vaccines recommended for use were AZD1222 and BNT162b2, both delivered as a two-dose primary schedule. In the absence of sustained immunity following immunisation, recommendations for booster vaccination have followed. It is likely that periodic boosting will be necessary for at least some Australians, but it is unknown what the optimal booster vaccines and schedules are or for whom vaccination should be recommended.
Nasal Delivery of Haemophilus haemolyticus Is Safe, Reduces Influenza Severity, and Prevents Development of Otitis Media in Mice
Despite vaccination, influenza and otitis media (OM) remain leading causes of illness. We previously found that the human respiratory commensal Haemophilus haemolyticus prevents bacterial infection in vitro and that the related murine commensal Muribacter muris delays OM development in mice. The observation that M muris pretreatment reduced lung influenza titer and inflammation suggests that these bacteria could be exploited for protection against influenza/OM.
B cell epitope mapping: The journey to better vaccines and therapeutic antibodies
B-cell epitope mapping is an approach that can identify and characterise specific antigen binding sites of B-cell receptors and secreted antibodies. The ability to determine the antigenic clusters of amino acids bound by B-cell clones provides unprecedented detail that will aid in developing novel and effective vaccine targets and therapeutic antibodies for various diseases.