This review highlights the significant sex-based differences in immune responses to influenza infection and vaccination. Men are generally more susceptible to severe influenza outcomes, while women often mount stronger immune responses but experience more adverse effects. These disparities are influenced by biological factors, including sex hormones and genes, as well as gender-related social and environmental conditions. Evidence from both human and animal studies reveals sex-specific variations in antibody production, vaccine effectiveness, and clinical outcomes. Age, hormonal status, and stress further modulate these differences. Understanding these complex interactions is essential for developing tailored and equitable vaccination and treatment strategies.

Immuno-materials, which represent a confluence of immunology and materials science, are dramatically transforming the fields of healthcare. Through the targeted modulation of immune responses, these innovative materials offer promising avenues for advancements in vaccine development, immunotherapy, tissue engineering, and diagnostics. This review examines the fundamental principles of immuno-materials, elucidating key concepts and methodologies pertinent to their development. We investigate strategies for engineering materials that can elicit customized immune responses, capable of both stimulation and suppression, and we discuss their potential roles as adjuvants, carriers, or scaffolds. Furthermore, we address the challenges and opportunities associated with the clinical translation of these materials, emphasizing the critical importance of biocompatibility, safety, and efficacy. This review aims to critically evaluate and contextualize the transformative potential of immuno-materials, mapping their journey from laboratory design to proven clinical applications in enhancing human health.

Autoimmune diseases (ADs) comprise a heterogeneous group of disorders characterised by a breakdown of immune tolerance and chronic immune-mediated tissue damage. Their onset and progression result from a complex interplay between genetic susceptibility, hormonal influences, immune regulatory mechanisms, and environmental exposures collectively referred to as the exposome. A striking feature of ADs is their pronounced sexual dimorphism, with a markedly higher prevalence in women for most conditions, alongside sex-specific differences in clinical presentation, severity, and prognosis. This review provides a comprehensive overview of the genetic and environmental determinants contributing to autoimmunity, with particular emphasis on how sex- and gender-related factors shape immune tolerance and disease susceptibility. We discuss central and peripheral tolerance mechanisms, the role of key regulators such as AIRE and FOXP3, sex chromosome-linked effects including X-chromosome inactivation, and the immunomodulatory impact of sex hormones across different life stages. Furthermore, we examine how environmental exposures, infections, and geographic variability interact with genetic background and sex-specific immune regulation to influence autoimmune disease risk. By integrating biological sex and gender-related factors within the framework of immune tolerance and the exposome, this review highlights the need for a sex-aware and personalised approach to understanding, diagnosing, and treating ADs.