MBP is a small, highly basic protein abundant in central nervous system myelin. Biochemically it is an intrinsically disordered, membrane‑binding protein present in multiple isoforms that helps organize lipids and proteins within the myelin sheath and contributes to compact myelin structure. MBP has been studied extensively as a model myelin antigen in immunology and neuroscience research. Laboratory detection of immune responses directed at MBP (for example, antibodies) has clinical research relevance because it reflects immune recognition of a core myelin component and can be one piece of evidence in mapping nervous‑system‑targeted immune activity.

Elevated immune reactivity to MBP may indicate increased immune recognition of myelin proteins, which can be associated with myelin stress, breakdown, or mechanisms that expose myelin components to the immune system. Such elevation is a signal of tissue‑specific immune activity rather than a standalone proof of a single condition. Low or absent MBP reactivity in the blood suggests little detectable humoral immune response to MBP at the time of testing. Absence of detectable reactivity does not rule out other immune processes, central nervous system activity localized behind the blood‑brain barrier, timing effects, or non‑antibody immune mechanisms. Results gain meaning when interpreted alongside other Immune Zoomer markers, clinical history, and additional testing as indicated.

MBP is included in the Immune Zoomer to assess neurological tissue immunity by detecting antibody reactivity to a core myelin protein. In combination with other neural markers (e.g., MAG, gangliosides, AQP4), MBP helps map immune targets and clarify whether immune activity is focused on myelin, supporting more precise interpretation of neurological symptom patterns and prioritization of further evaluation.