Cancer, autoimmune diseases, infectious diseases, and immunodeficiencies (primary or acquired) are prevalent disorders in developed countries, and they are also the leading causes of morbidity and mortality in Hong Kong and many other countries in this region. These conditions are underpinned by dysregulated immune reactions, highlighting the importance of rebalancing the immune response as a pivotal element in disease management and curative treatment. While researchers in Hong Kong have made significant strides in characterising the clinical presentation and outcomes of these conditions, translational immunology research in these areas is still in its infancy.