Understanding immunity: an alternative framework beyond defense and strength

Updating the Discontinuity Theory to the Extended Immunity: The Symmunobiome Concept

The immune system (IS) is commonly understood as a system composed of specific cells and tissues that have evolved to contrast pathogens and defend the host. By virtue of this capacity, it has come to be considered capable of making an essential distinction, that between self versus non-self, which would contribute to a clear identity of the organism. However, in the wake of evolution and ecology, growing evidence suggests that the so-called immune system, which also evolved from symbiotic interactions with external agents, is not just a defensive system that merely protects the organism but, on the contrary, is involved in many global regulatory and homeostatic functions. Moreover, in performing these many functions, IS is not only an ensemble of host cells and tissues but functionally is constitutively determined by the interaction with a set of associated microorganisms, that is, the human microbiome. In this scenario, it is open-and-shut that the microbiome itself is a functional part of this extended immune system. Organisms and microbiomes together, therefore, form a functional whole, which constitutes a privileged form of biological organization. In light of this evidence showing the inadequacy of traditional accounts, we propose to extend and supplement the current IS conceptualization by introducing the notion of the symmunobiome. With this term, we intend to characterize the microbiome's own and unavoidable component to overall immune functionality. Therefore, we suggest a new immune system determination, articulated in three linked pillars-adaptive immunity, innate immunity, and symmunobiome-to better grasp the diverse functionality of extended immunity.

Human immune system: Exploring diversity across individuals and populations

The immune response is an intricate system that involves the complex connection of cellular and molecular components, each with distinct functional specialisations. It has a distinct capacity to adjust and mould the immune response in accordance with specific stimuli, influenced by both genetic and environmental factors. The presence of genetic diversity, particularly across different ethnic and racial groups, significantly contributes to the impact of incidence of diseases, disease susceptibility, autoimmune disorders, and cancer risks in specific regions and certain populations. Environmental factors, including geography and socioeconomic status, further modulate the variety of the immune system responses. These, in turn, affect the susceptibility to infectious diseases and development of autoimmune disorders. Despite the complexity of the relationship, there remains a gap in understanding the specificity of immune indices across races, immune reference ranges among populations, highlighting the need for deeper understanding of immune diversity for personalized approaches in diagnostics and therapeutics. This review systematically organizes these findings, with the goal of emphasizing the potential of targeted interventions to address health disparities and advance translational research, enabling a more comprehensive strategy. This approach promises significant advancements in identifying specific immunological conditions, focusing on personalized interventions, through both genetic and environmental factors.

The good or the bad: an overview of autoantibodies in traumatic spinal cord injury

Infections remain the most common cause of death after traumatic spinal cord injury, likely due to a developing immune deficiency syndrome. This, together with a somewhat contradictory development of autoimmunity in many patients, are two major components of the maladaptive systemic immune response. Although the local non-resolving inflammation in the lesioned spinal cord may lead to an antibody formation against autoantigens of the injured spinal cord tissue, there are also natural (pre-existing) autoantibodies independent of the injury. The way in which these autoantibodies with different origins affect the neuronal and functional outcome of spinal cord-injured patients is still controversial.

Reuniting philosophy and science to advance cancer research

Cancers rely on multiple, heterogeneous processes at different scales, pertaining to many biomedical fields. Therefore, understanding cancer is necessarily an interdisciplinary task that requires placing specialised experimental and clinical research into a broader conceptual, theoretical, and methodological framework. Without such a framework, oncology will collect piecemeal results, with scant dialogue between the different scientific communities studying cancer. We argue that one important way forward in service of a more successful dialogue is through greater integration of applied sciences (experimental and clinical) with conceptual and theoretical approaches, informed by philosophical methods. By way of illustration, we explore six central themes: (i) the role of mutations in cancer; (ii) the clonal evolution of cancer cells; (iii) the relationship between cancer and multicellularity; (iv) the tumour microenvironment; (v) the immune system; and (vi) stem cells. In each case, we examine open questions in the scientific literature through a philosophical methodology and show the benefit of such a synergy for the scientific and medical understanding of cancer.