Major histocompatibility complex class II (MHC II) expression in the normal and pathological human foetal spinal cord

Area of Science:

• Neuroimmunology
• Developmental Biology
• Immunogenetics

Background:

• Major histocompatibility complex class II (MHC II) molecules are crucial for adaptive immunity, presenting antigens to T lymphocytes.
• Their expression on antigen-presenting cells is vital for immune response initiation, B cell activation, and antibody production.

Purpose of the Study:

• To investigate the expression patterns of MHC II molecules in the developing human spinal cord.
• To compare MHC II expression in normal fetuses versus those with genetic defects.

Main Methods:

• Immunocytochemistry was used to detect MHC II molecules.
• Spinal cord tissues from normal and genetically abnormal human fetuses (11-22 weeks gestation) were analyzed across different regions.

Main Results:

• MHC II molecules were present throughout the spinal cord (cervical, thoracic, lumbar, sacral) in all studied fetuses.
• Expression was observed in both grey and white matter, particularly on microglia near the central canal and blood vessels.
• No significant differences in MHC II expression were found between spinal cord regions or between normal and genetically defective fetuses.

Conclusions:

• Early and widespread expression of MHC II in the fetal spinal cord suggests a critical role in fetal immunological protection.
• The consistent expression, even in fetuses with genetic defects, highlights its fundamental importance for normal embryogenesis.