Spätphase

Spätphase is a German term that literally means “late phase.” In scientific and medical contexts it is used to denote the later stage of a process, as opposed to an immediate or early phase. The exact meaning can vary by field, but it generally refers to events or reactions that occur hours after an initiating trigger.

In immunology and allergy research, the Spätphase (late phase) describes the inflammatory response that follows the initial, immediate reaction to a stimulus such as an allergen. This late phase typically begins several hours after exposure—often around 4 to 24 hours—and can persist for many hours or days. It is characterized by the recruitment of leukocytes such as eosinophils and neutrophils, the activation of T cells, and the release of cytokines (for example IL-4, IL-5, IL-13) as well as chemokines and lipid mediators. Clinically, it can contribute to prolonged symptoms like airway hyperreactivity in asthma, nasal congestion, or skin swelling.

Therapeutically, late-phase responses are a target of anti-inflammatory strategies. Corticosteroids, leukotriene receptor antagonists, and other agents aim to dampen the sustained inflammation of the late phase and reduce tissue damage and symptom burden.

Outside medicine, Spätphase is also used in other disciplines to denote the later stage of various processes, with the exact timing and implications depending on the specific context. The term is not a fixed technical label across all fields and should be interpreted in context.