The immune system enters the depth-psychology corpus not as mere biological machinery but as a site where somatic, psychological, and relational forces converge. Damasio situates the immune system within a phylogenetically ancient class of homeostatic sentinels — alongside the circulatory, endocrine, and nervous systems — arguing that immunity constitutes one of the earliest defenders of organismic integrity and a primary contributor to affective valence. Schore extends this picture into developmental psychobiology, mapping how early relational trauma disrupts the hierarchical cortical-neuroendocrine-immune network, opening pathways to psychosomatic illness through dysregulated cortisol and impaired lymphocyte function. Maté pushes the clinical argument further: autoimmune conditions, NK-cell suppression, and inflammatory cascades are presented as somatic transcriptions of chronic emotional suppression, grief, and adversity. Kalsched imports the immunological metaphor directly into analytical psychology, following Leopold Stein’s provocative proposal that the primal Self operates as a psychic immune system — capable, under traumatic conditions, of misidentifying ego-elements as foreign and launching a self-destructive autoimmune attack. Lench contributes a functional-emotion perspective, noting that immune activation competes metabolically with voluntary movement, explaining the anergia and anhedonia that accompany illness. Han reads immunological logic culturally, arguing that the positivity excess of achievement society bypasses immune-style defences altogether. Across these registers, the immune system serves as a theoretical pivot between biology, psychology, and culture.