Relapsing autoimmune demyelination: a role for vascular addressins

Area of Science:

• Immunology
• Neuroscience
• Pathology

Background:

• Vascular addressins are key adhesion molecules regulating lymphocyte trafficking to lymphoid and mucosal tissues via high endothelial venules (HEV).
• Experimental autoimmune encephalomyelitis (EAE) is a model for chronic relapsing inflammatory diseases of the central nervous system (CNS).

Purpose of the Study:

• To investigate the expression patterns of specific vascular addressins and an HEV differentiation antigen in the CNS during different stages of EAE.
• To explore the potential differential roles of these molecules in the pathogenesis of EAE.

Main Methods:

• Immunocytochemical analysis was performed on CNS tissues from SJL mice with adoptively-transferred, chronic relapsing EAE.
• Monoclonal antibodies (mAbs) MECA-325 (HEV antigen), MECA-89 and MECA-367 (mucosal addressin), and MECA-79 (peripheral lymph node addressin) were used.

Main Results:

• MECA-325 showed high expression on blood vessels in spinal cord lesions during active inflammation (acute onset and relapses).
• MECA-89 and MECA-367 stained endothelial cells and astrocytes in lesions during relapses only.
• MECA-79 did not stain CNS tissues, while all antibodies stained control lymphoid tissues.

Conclusions:

• The differential expression of vascular addressins in the CNS during EAE suggests distinct roles for these molecules in lymphocyte infiltration and CNS inflammation.
• Further investigation into the specific functions of each addressin during EAE is warranted.